Cromme, L; Völler, H; Gäbler, F; Salzwedel, A; Taborski, U
Oral anticoagulation using vitamin K antagonists has been established for over 50 years. Although it is highly effective in preventing thromboembolic incidents, its therapeutic control still remains problematic. Therefore, a computer-aided approach is recommended for deriving dosages. Up to now, the dosage is often based on the visual inspection of previous INR measurements, average weekly doses, and the INR target range. Statistical variations of measurement results and time-delayed effects of dosages, however, frequently result in the misinterpretation of data and suggest pseudo-trends. Treating physicians are not only responsible for determining the patient-specific maintenance dose, but must also respond to deviating INR values, overdosage or underdosage, initiate the oral anticoagulation therapy, and control the INR level in case of a new target range (bridging). Instructive examples are provided to illustrate the described difficulties. A computer-aided expert system is currently developed to ensure the therapeutic safety under the specified conditions. We present preliminary results from a study designed to validate mathematical models underlying such expert systems.
Gallus, Alexander S.; Wittkowsky, Ann; Crowther, Mark; Hylek, Elaine M.; Palareti, Gualtiero
Background: The objective of this article is to summarize the published literature concerning the pharmacokinetics and pharmacodynamics of oral anticoagulant drugs that are currently available for clinical use and other aspects related to their management. Methods: We carried out a standard review of published articles focusing on the laboratory and clinical characteristics of the vitamin K antagonists; the direct thrombin inhibitor, dabigatran etexilate; and the direct factor Xa inhibitor, rivaroxaban Results: The antithrombotic effect of each oral anticoagulant drug, the interactions, and the monitoring of anticoagulation intensity are described in detail and discussed without providing specific recommendations. Moreover, we describe and discuss the clinical applications and optimal dosages of oral anticoagulant therapies, practical issues related to their initiation and monitoring, adverse events such as bleeding and other potential side effects, and available strategies for reversal. Conclusions: There is a large amount of evidence on laboratory and clinical characteristics of vitamin K antagonists. A growing body of evidence is becoming available on the first new oral anticoagulant drugs available for clinical use, dabigatran and rivaroxaban. PMID:22315269
Rojas-Hernandez, Cristhiam M; Garcia, David A
After the introduction of warfarin, long-term oral anticoagulation treatment remained unchanged for more than 50 years. Most recently, with the development and approval of new oral anticoagulants, the treatment of medical conditions that require thrombosis prophylaxis and long-term anticoagulation has become more complex. In the case of venous thromboembolism (VTE) prevention after orthopedic surgery, the new oral agents will be less costly than the parenteral alternative. In other settings (such as atrial fibrillation or treatment of acute VTE), the new agents will offer additional convenience at higher cost, but the degree to which they will reduce clinically important events such as thrombosis or bleeding will be limited, especially for patients on optimally controlled warfarin. As the use of the new oral anticoagulants becomes more widespread, it will be important for all clinicians to have a basic understanding of their pharmacology, advantages, and limitations. Although the need to measure or reverse the effect of these drugs will arise infrequently, clinicians--especially hematologists--will desire evidence-based recommendations about how to manage such scenarios, which will require research studies.
Carter, Cedric J.
The author briefly reviews the use of anticoagulants, describing the specific tests their use requires. These tests are usually performed in a specialized laboratory. The clinical implication of the laboratory's use of different prothrombin time systems is explained. Implications of the use of oral anticoagulants in family practice are discussed. PMID:21253057
Talarico, Anna; Fabbri, Matteo; Bertocco, Cesare; Vigliano, Marco; Moratelli, Stefano; Cuneo, Antonio; Serino, Maria Luisa; Avato, Francesco Maria
Objectives Warfarin oral anticoagulant therapy (OAT) requires regular and frequent drug adjustment monitored by INR. Interindividual variability, drug and diet interferences, and genetics (VKORC1 and CYP2C9) make the maintenance/reaching of stable INR a not so easy task. HPLC assessment of warfarin/enantiomers was suggested as a valid monitoring-tool along with INR, but definite results are still lacking. We evaluated possible correlations between INR, warfarin/3’-hydroxywarfarin, and drug weekly dosage aimed at searching novel alternatives to OAT monitoring. VKORC1/CYP2C9 pharmacogenetics investigation was performed to account for the known influence on warfarin homeostasis. Methods 133 OAT patients were recruited and assessed for warfarin/3’-hydroxywarfarin serum levels (HPLC), INR, and VKORC1 and CYP2C9 genotypes. A subgroup of 52 patients were monitored in detail (5 consecutive controls; c0-c4) till the target INR was reached. Correlation analyses were performed in both groups Results In the whole OAT group both warfarin and 3’-hydroxywarfarin correlate with INR at comparable degree (r2 = 0.0388 and 0.0362 respectively). Conversely, warfarin weekly dosage better correlates with warfarin than with 3’-hydroxywarfarin (r2 = 0.0975 and r2 = 0.0381 respectively), but considering together warfarin plus 3’-hydroxywarfarin the correlation strongly increased (r2 = 0.1114; p<0.0001). Interestingly, 3’-hydroxywarfarin reached a strong correlation at c4 respect to warfarin (r2 = 0.2157 and r2 = 0.0549; p = 0.0005 and p = 0.0944 respectively) seeming less affected by drug adjustments in the subgroup of 52 patients who started OAT. The multivariate analyses aimed at estimating the true contribution of 3’-hydroxywarfarin on INR value ascribed it the unique significant value (p = 0.0021) in spite of warfarin who lost association. The pharmacogenetics studies confirmed that patients carrying the VKORC1 variant-allele required lower warfarin maintenance dosage and
Sáez-Peñataro, J; Avendaño-Solá, C; González-Juanatey, J R
The efficacy of dicoumarin anticoagulants has been shown in patients with nonvalvular atrial fibrillation. However, they have drawbacks such as the need to adjust the dosage and the interaction with drugs and food. Direct oral anticoagulants are an effective and safe alternative and have a less complicated clinical management. There is considerable debate on the selection criteria for the posology regimens of direct oral anticoagulants. The differences among them and their administration regimens have raised questions about the clinical, pharmacokinetic and pharmacodynamic selection criteria that support the posology. This review critically analyses the available evidence and its impact on the final selection of the dosage regimen.
Barnes, Geoffrey D; Nallamothu, Brahmajee K; Sales, Anne E; Froehlich, James B
Anticoagulation clinics were initially developed to provide safe and effective care for warfarin-treated patients with atrial fibrillation, venous thromboembolism, and mechanical valve replacement. Traditionally, these patients required ongoing laboratory monitoring and warfarin dose adjustment by expert providers. With the introduction of direct oral anticoagulants (dabigatran, rivaroxaban, apixaban, and edoxaban), many have questioned the need for anticoagulation clinic. However, we think that the growing number of oral anticoagulant choices creates an urgent need for expanding the traditional role of the anticoagulation clinic. We outline 3 key purposes that a reimagined anticoagulation clinic would serve: (1) to assist patients and clinicians with selecting the most appropriate drug and dose from a growing list of anticoagulant options (including warfarin), (2) to help patients minimize the risk of serious bleeding complications with careful long-term monitoring and peri-procedural management, and (3) to encourage ongoing adherence to these life-saving medications. We also describe how repurposing anticoagulation clinics as broader medication safety clinics would promote safe and effective care across a range of cardiovascular conditions for high-risk medications (eg, spironolactone, amiodarone). Finally, we highlight a few existing health systems that are overcoming key challenges to implementing a reimagined anticoagulation or medication safety clinic structure.
Barnes, Geoffrey D.; Nallamothu, Brahmajee K.; Sales, Anne E.; Froehlich, James B.
Anticoagulation clinics were initially developed to provide safe and effective care for warfarin-treated patients with atrial fibrillation, venous thromboembolism and mechanical valve replacement. Traditionally, these patients required ongoing laboratory monitoring and warfarin dose adjustment by expert providers. With the introduction of direct oral anticoagulants (dabigatran, rivaroxaban, apixaban and edoxaban), many have questioned the need for anticoagulation clinic. However, we believe the growing number of oral anticoagulant choices creates an urgent need for expanding the traditional role of the anticoagulation clinic. We outline three key purposes that a “re-imagined” anticoagulation clinic would serve: 1) to assist patients and clinicians with selecting the most appropriate drug and dose from a growing list of anticoagulant options (including warfarin), 2) to help patients minimize the risk of serious bleeding complications with careful long-term monitoring and peri-procedural management, and 3) to encourage ongoing adherence to these life-saving medications. We also describe how re-purposing anticoagulation clinics as broader “medication safety clinics” would promoting safe and effective care across a range of cardiovascular conditions for high-risk medications (e.g. spironolactone, amiodarone). Finally, we highlight a few existing health systems that are overcoming key challenges to implementing a re-imagined anticoagulation or medication safety clinic structure. PMID:26933047
Chronic antithrombotic therapy involves the use of anticoagulants, antiplatelets given either as monotherapy or in combination for the prevention of thrombotic complications. The most feared and sometimes fatal complication with this therapy is bleeding. It should be considered a “golden rule” that a drug or combination of drugs that maximizes efficiency (decreased thromboembolic risk) will probably be less safe (increased risk of bleeding), and this holds true either for single therapy or during combined therapy. The chances of bleeding indicated by risk tables can be useful but show only a snapshot, and the biological, social, environmental, and drug changes and therapeutic adherence also determine changes in the risk of thrombosis and bleeding. Bleeding is an eventuality that occurs in places of “locus minoris resistentiae,” and the results of careful phase 3 studies thus cannot be completely predictive of outcomes when a medication is introduced on the pharmaceutical market. With the use of warfarin, the International Normalized Ratio (INR) that has been established to indicate adequately balanced therapy is between 2.0 and 3.0. With the new oral anticoagulants, the pharmaceutical companies emphasize that it is not necessary to monitor anticoagulant effects. In studies with different doses of new oral anticoagulants, however, incidence of clinically significant bleeding complications have been directly related to the doses. Therefore, therapeutic excesses can condition bleeding risk and therapeutic limitation can increase thrombotic risk, especially when short-acting drugs such as the new oral anticoagulants are used. Hence, it is imperative to establish an appropriate method for monitoring new oral anticoagulants, setting levels of safety and effectiveness through periodic dosage and monitoring of their anticoagulant effects. Therefore, we still recommend the use of anticoagulation units for monitoring during treatment with the new oral anticoagulants
António, Natália; Castro, Graça; Ramos, Domingos; Machado, António; Gonçalves, Lino; Macedo, Tice; Providência, Luís A
The management of patients taking long-term oral anticoagulants who require dental surgery is still highly controversial. The risk of bleeding associated with dental treatment under oral anticoagulants must be weighed against the risk of thromboembolism associated with suspension of antithrombotic therapy. Mortality and morbidity associated with thromboembolic events are higher than those associated with hemorrhagic events after minor oral surgery procedures. Evidence-based information does not support oral anticoagulant suspension before minor oral surgery. The authors propose a management protocol for chronically anticoagulated patients who require a dental procedure, to reduce both thromboembolic risk and the risk of bleeding.
Thromboembolic disease is a major leading cause of mortality and morbidity in industrialized countries. Currently, the management of these patients is challenging due to the availability of new drugs with proven efficacy and security compared to traditional oral vitamin K antagonists. These compounds are characterized by a predictable pharmacokinetic profile for which blood monitoring is not routinely needed. Nevertheless, some data have suggested inter-patient variability in the anticoagulant effect of these drugs, raising concerns about their effectiveness and safety. Although mass-spectrometry is the gold standard to determine drug plasma concentrations, this method is not widely available in every-day practice and some coagulation assays are commonly used to determine the anticoagulant effect of these drugs. The present review aims to summarize the current knowledge regarding the clinical question of how and when to monitor patients with new anticoagulant oral agents. PMID:26713281
Patel, Anand; Goddeau Jr, Richard P.; Henninger, Nils
Warfarin is very effective in preventing stroke in patients with atrial fibrillation. However, its use is limited due to fear of hemorrhagic complications, unpredictable anticoagulant effects related to multiple drug interactions and dietary restrictions, a narrow therapeutic window, frequent difficulty maintaining the anticoagulant effect within a narrow therapeutic window, and the need for inconvenient monitoring. Several newer oral anticoagulants have been approved for primary and secondary prevention of stroke in patients with non-valvular atrial fibrillation. These agents have several advantages relative to warfarin therapy. As a group, these direct oral anticoagulants (DOAC), which include the direct thrombin inhibitor, dabigatran, and the factor Xa inhibitors (rivaroxaban, apixaban, and edoxaban), are more effective than dose adjusted warfarin for prevention of all-cause stroke (including both ischemic and hemorrhagic stroke), and have an overall more favorable safety profile. Nevertheless, an increased risk of gastrointestinal bleeding (with the exception of apixaban), increased risk for thrombotic complication with sudden discontinuation, and inability to accurately assess and reverse anticoagulant effect require consideration prior to therapy initiation, and pose a challenge for decision making in acute stroke therapy. PMID:27347226
Altman, R; Rouvier, J; Gurfinkel, E
For preventing thromboembolic events, the concurrent use of oral anticoagulant and antiplatelet drugs has been proposed. In prosthetic heart valves the use of moderate intensity anticoagulants [International Normalized Ratio (INR) 2-3] plus aspirin (100 mg/day) decreases the amount and severity of embolic episodes. The possibility that the same regimen could provide benefit in the prevention of thrombotic events in other arterial diseases is also indicated by the ATACS trial in unstable angina. The ongoing studies in ischemic heart diseases will also give the answer to this possibility.
Prisco, Domenico; Cenci, Caterina; Silvestri, Elena; Ciucciarelli, Lucia; Di Minno, Giovanni
Atrial fibrillation is the most common rhythm disorder and represents a major public health problem because it carries an increased risk of arterial thromboembolism and ischemic stroke. Current european society of cardiology guidelines recommend to stratify atrial fibrillation patients according to the CHA2DS2-VASc score and to administer anticoagulation, preferably with novel oral anticoagulants, that is, dabigatran, rivaroxaban, or apixaban, if the CHA2DS2-VASc score is at least 1. All novel anticoagulants have shown the same, if not greater, efficacy and safety as warfarin, with some advantages. The choice among the novel oral anticoagulants depends on their different pharmacokinetic profile, patients' stroke and bleeding risk, comorbidities, drug tolerability and costs and, finally, patients' preferences.
Moreno Villar, A; Nacle López, I; Barbero Hernández, M J; Lizan Tudela, L
In an attempt to minimize the economic impact due to the incorporation of innovative drugs, health authorities have promoted and supported the evaluation and market positioning of drugs, as equivalent therapeutic alternatives. This issue has recently gained importance, possibly due to the current economic crisis. The equivalent therapeutic alternatives are justified by the need to compete on price, and by the authorities recommendation to establish therapeutic equivalence, price and financing of medicinal products at the same time. The establishment of the new oral anticoagulants and the equivalent therapeutic alternatives is a problematic issue if it is based on the absence of direct comparisons between different drugs and the questionable methodology used in the current indirect comparisons. Currently, it is difficult to determine when a new oral anticoagulant is more recommendable than others, but efforts are being made in order to propose alternatives for the decision based on patient characteristics.
Veltkamp, R; Hacke, W
Atrial fibrillation (AF) causes at least 20% of all ischemic strokes. In large randomized trials of primary and secondary stroke prevention, anticoagulation with vitamin K antagonists (VKA) protected much more efficiently than antiplatelet agents against stroke. Because of the problematic pharmacological properties of VKA only part of the AF patients are currently being treated with oral anticoagulants (OAK). The targeted development of specific oral inhibitors of the central coagulation factors thrombin and factor Xa allows reliable anticoagulation without regular coagulation monitoring. In the present review, pharmacological properties of the different agents are compared. Of the four large randomized phase 3 studies in AF (RELY, ROCKET-AF, ARISTOTLE, ENGAGE-AF) with the primary efficacy endpoint stroke and systemic embolism, the published data from the RELY trial indicate a superior efficacy of dabigatran etexilate (2 × 150 mg/day) and a lower risk of intracranial hemorrhage compared to warfarin. Favorable preliminary results have been demonstrated for the factor Xa inhibitor rivaroxaban. Apixaban was more efficacious than ASA and had a similar risk of hemorrhage in the AVERROES study. Thus, the available data suggest a favorable benefit-risk ratio for the new substances in addition to improved patient comfort. Currently unresolved issues relate to the verification of patient adherence by suitable coagulation tests and to the emergency coagulation diagnostics and therapy in acute ischemic or hemorrhagic strokes under the new OAC.
Albaladejo, Alberto; Alvarado, Alfonso
Background A new group of oral anticoagulants (dabigatran, rivaroxaban, apixaban and edoxaban) with clear advantages over classic dicoumarin oral anticoagulants (warfarin and acenocoumarol) has been developed in recent years. Patients being treated with oral anticoagulants are at higher risk for bleeding when undergoing dental treatments. Material and Methods A literature search was conducted through April 2016 for publications in the ISI Web of Knowledge, PubMed and Cochrane Library using the keywords “dabigatran”, “rivaroxaban”, “apixaban”, “edoxaban”, “new oral anticoagulants”, “novel oral anticoagulants”, “bleeding” and “dental treatment”. Results There is no need for regular coagulation monitoring of patients on dabigatran therapy. Whether or not to temporarily discontinue dabigatran must be assessed according to the bleeding risk involved in the dental procedure to be performed. Conclusions The number of patients under treatment with new oral anticoagulants will increase in the coming years. It is essential to know about the pharmacokinetics and pharmacodynamics of new oral anticoagulants and about their interactions with other drugs. It is necessary to develop clinical guidelines for the perioperative and postoperative management of these new oral anticoagulants in oral surgical procedures, and to carefully evaluate the bleeding risk of dental treatment, as well as the thrombotic risk of suppressing the new oral anticoagulant. Key words:Dabigatran, rivaroxaban, apixaban, edoxaban, novel oral anticoagulants, bleeding. PMID:28210451
Munson, C F; Reid, A J
Novel oral anticoagulants (NOACs) have emerged as a good alternative to warfarin in the prevention of stroke for patients with atrial fibrillation. NOAC use is increasing rapidly; therefore, greater understanding of their use in the perioperative period is important for optimal care. Studies and reviews that reported on the use of NOACs were identified, with particular focus on the perioperative period. PubMed was searched for relevant articles published between January 2000 and August 2015. The inevitable rise in the use of NOACs such as rivaroxaban (Xarelto™), apixaban (Eliquis™), edoxaban (Lixiana™) and dabigatran (Pradaxa™) may present a simplified approach to perioperative anticoagulant management due to fewer drug interactions, rapidity of onset of action and relatively short half-lives. Coagulation status, however, cannot reliably be monitored and no antidotes are currently available. When planning for discontinuation of NOACs, special consideration of renal function is required. Advice regarding the management of bleeding complications is provided for consideration in emergency surgery. In extreme circumstances, haemodialysis may be considered for bleeding with the use of dabigatran. NOACs will increasingly affect operative planning in plastic surgery. In order to reduce the incidence of complications associated with anticoagulation, the management of NOACs in the perioperative period requires knowledge of the time of last dose, renal function and the bleeding risk of the planned procedure. Consideration of these factors will allow appropriate interpretation of the current guidelines.
Fitzmaurice, D A; Murray, E T; McCahon, D; Holder, R; Raftery, J P; Hussain, S; Sandhar, H; Hobbs, F D R
Objective To determine the clinical effectiveness of self management compared with routine care in patients on long term oral anticoagulants. Design Multicentre open randomised controlled trial. Setting Midlands region of the UK. Participants 617 patients aged over 18 and receiving warfarin randomised to intervention (n = 337) and routine care (n = from 2470 invited; 193/337 (57%) completed the 12 month intervention. Intervention Intervention patients used a point of care device to measure international normalised ratio twice a week and a simple dosing chart to interpret their dose of warfarin. Main outcome measure Percentage of time spent within the therapeutic range of international normalised ratio. Results No significant differences were found in percentage of time in the therapeutic range between self managment and routine care (70% v 68%). Self managed patients with poor control before the study showed an improvement in control that was not seen in the routine care group. Nine patients (2.8/100 patient years) had serious adverse events in the self managed group, compared with seven (2.7/100 patient years) in the routine care arm (χ2(df = 1) = 0.02, P = 0.89). Conclusion With appropriate training, self management is safe and reliable for a sizeable proportion of patients receiving oral anticoagulation treatment. It may improve the time spent the therapeutic range for patients with initially poor control. Trial registration ISRCTN 19313375. PMID:16216821
Diagnostic of global coagulation parameters is part of the daily clinical routine practice in conservative as well in operative disciplines. The correct interpretation of in vitro test results in context to the ex vivo influence of anticoagulant drugs and the in vivo hemostatic system of the individual patient is dependent on the doctors clinical and laboratory experience. This article shortly reviews the laboratory interference of oral anticoagulants including the target-specific inhibitors dabigatran, rivaroxaban and apixaban on coagulation parameters and discusses the potential of several methods for measuring the anticoagulant effect of the direct oral anticoagulants.
Weibert, R T
The literature on dental surgery in patients receiving oral anticoagulants is reviewed, and methods of managing anticoagulant therapy to minimize the risk of complications are discussed. Although blood loss during and after oral surgery in patients receiving oral anticoagulant drugs can be substantial, research indicates that most bleeding incidents are not serious and can be controlled by local measures. Studies of 241 anticoagulant-treated patients undergoing more than 500 dental extractions during the 1950s and 1960s showed that only 9 had postoperative bleeding. More recent studies indicate that continued anticoagulation can increase the frequency of prolonged bleeding and delay wound healing. An antifibrinolytic mouthwash containing tranexamic acid can effectively suppress postoperative bleeding. Gelatin sponges, oxidized cellulose, and microcrystalline collagen are other useful hemostatic agents. A reduction in the intensity of anticoagulation therapy has been recommended; the prothrombin time should be measured shortly before the procedure in such patients. In many patients the duration of subtherapeutic anticoagulation must be minimized to reduce the possibility of thromboembolism. An option for high-risk patients is to switch them to heparin. Each patient must be evaluated individually, and the level of risk of the dental procedure and the risk of thromboembolism should be taken into account. In patients taking oral anticoagulants who must undergo dental surgery, careful control of the intensity of anticoagulation and improved methods of local hemostasis can minimize the risk of hemorrhagic complications and thromboembolism.
Costopoulos, Charis; Niespialowska-Steuden, Maria; Kukreja, Neville; Gorog, Diana A
Coronary artery disease (CAD) is a leading cause of morbidity and mortality worldwide with a prevalence that has now reached pandemic levels as a consequence of the rapid modernization of the developing world. Its presentation as an acute coronary syndrome (ACS) is a frequent reason for hospital admission and of profound implications for personal, societal and global health. Despite improvements in the management of ACS with anti-platelet and anticoagulant therapy and revascularization techniques, many patients continue to suffer recurrent ischemic events. The need to reduce future cardiovascular events has led to the development of novel therapies to prevent coronary thrombosis, targeting thrombin-mediated pathways. These include direct Xa inhibitors (apixaban, rivaroxaban and darexaban), direct thrombin inhibitors (dabigatran) and PAR 1 antagonists (vorapaxar and atopaxar). This article critically reviews the comparative mechanisms of action, the risks and benefits, together with the clinical evidence base for the use of these novel oral agents in the management of ACS patients.
Khorev, N G; Momot, A P; Kon'kova, V O
During the last 10 years, several novel direct oral anticoagulants (NOACs) have entered the clinical arena and were registered in the Russian Federation for use in patients presenting with atrial fibrillation, venous thrombosis, and pulmonary artery thromboembolism. NOACs are classified into two groups: direct thrombin inhibitor (notably dabigatran) and factor Xa inhibitors (including rivaroxaban, apixaban, and edoxaban). Their disadvantage is lack of specific antidotes in case of an emergency situation (injury, infarction, stroke requiring thrombolysis, urgent operation). The review contains the data on the existing therapeutic regimens of treating haemorrhage on the background of taking these coagulants. This is followed by analysing the present-day results of clinical trials aimed at working out pharmaceutical agents (andexanet alpha, idarucizumab, aripazine) being antidotes to direct thrombin inhibitor and the factor Xa inhibitors. Administration of these agents makes it possible to reverse coagulation and minimize the aftermaths of haemorrhage in patients taking these drugs, in emergency situations.
Capranzano, Piera; Miccichè, Eligio; D'Urso, Lucia; Privitera, Fiorella; Tamburino, Corrado
For decades, warfarin has remained the standard oral anticoagulation for stroke prevention in atrial fibrillation (AF). Three novel oral anticoagulants (NOACs) have been recently approved for stroke prevention in non-valvular AF: dabigatran, rivaroxaban and apixaban. Better pharmacological and clinical profiles make these newcomers a preferable alternative over warfarin. Current AF guidelines do not endorse NOACs over warfarin, or one NOAC over another. Indeed, choice of the anticoagulation regimen should be personalized based on the relative efficacy and safety of different agents across subgroups stratified by thrombotic and bleeding risk, as well as on other clinical factors, including anticoagulation control on warfarin, drug interactions, compliance and need for coagulation monitoring. This review appraises i) the randomized evidence on approved NOACs versus warfarin in AF across subgroups stratified by risk factors of stroke and bleeding and by the anticoagulation level reached on warfarin; and ii) clinical factors impacting on the anticoagulation regimen selection.
Sivolella, Stefano; De Biagi, Marleen; Brunello, Giulia; Berengo, Mario; Pengo, Vittorio
The development of new orally administered anticoagulants, such as dabigatran, rivaroxaban, and apixaban, in the past few years has focused on avoiding some of the drawbacks associated with warfarin. This work aims to illustrate the main features of the most commonly used new oral anticoagulants, reviewing the current literature on the management of patients taking these drugs and needing oral and implant surgery, and discussing the currently proposed related guidelines.
Hankey, Graeme J; Norrving, Bo; Hacke, Werner; Steiner, Thorsten
Each year, 1·0–2·0% of individuals with atrial fibrillation and 0·1–0·2% of those with venous thromboembolism who are receiving one of the novel oral anticoagulants (dabigatran, rivaroxaban, or apixaban) can be expected to experience an acute ischemic stroke. Additionally, 0·2–0·5% of individuals with atrial fibrillation who are receiving one of the novel oral anticoagulants can be expected to experience an intracranial hemorrhage. This opinion piece addresses the current literature and offers practical approaches to the management of patients receiving novel oral anticoagulants who present with an ischemic or hemorrhagic stroke. Specifically, we discuss the role of thrombolysis in anticoagulated patients with acute ischemic stroke and factors to consider concerning restarting anticoagulation after acute ischemic and hemorrhagic stroke. PMID:24891030
Daniels, Paul R
The use of oral anticoagulants is becoming increasingly common. For many years warfarin was the main oral anticoagulant available, but therapeutic options have expanded with the introduction of oral direct thrombin (dabigatran) and factor Xa inhibitors (apixaban, rivaroxaban, and edoxaban). Management of patients taking any oral anticoagulant in the peri-procedural period poses a challenge to medical and surgical providers because of the competing risks of thrombosis and hemorrhage. Bridging therapy has been used to minimize time without anticoagulation when warfarin is interrupted for invasive procedures, but validated strategies based on high quality data are lacking. Existing data suggest that the use of bridging therapy may increase the risk of bleeding for some patients without reducing the risk of thrombosis. Clinical trials are currently under way to answer these questions. Because the half lives and time to anticoagulant activity of newer oral anticoagulants are shorter than for warfarin, bridging therapy is not thought to be necessary with these agents. Peri-procedural management of patients taking these agents is complicated by the lack of demonstrated reversal agents in emergency situations, although specific antidotes are being developed and tested. Existing guidelines for peri-procedural management of patients on oral anticoagulants highlight the importance of individualized patient decision making and suggest strategies to minimize complications. From a patient's perspective, given the uncertainties surrounding optimal management, explicit discussions regarding risks and benefits of treatment options and demonstration of effective communication among medical and surgical providers are essential.
Doonquah, Ladi; Mitchell, Anika D
Minor oral surgical procedures make up a significant part of the daily practice of dentistry. With the increased sophistication of medical technology and medications there is increased likelihood of performing surgery on patients who are being treated for conditions that require some type of anticoagulant therapy. These patients are at an increased risk for perioperative bleeding or thrombotic complications if anticoagulation is discontinued or the dosage is adjusted. Therefore, a fine balance needs to be obtained and adequate preparation of these patients is the key to establishing this balance. This article reviews suggested approaches to the management of such patients.
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... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Thiabendazole oral dosage forms. 520.2380 Section... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.2380 Thiabendazole oral dosage forms....
... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sulfaquinoxaline oral dosage forms. 520.2325... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.2325 Sulfaquinoxaline oral dosage forms....
... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Spectinomycin oral dosage forms. 520.2123 Section... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.2123 Spectinomycin oral dosage forms....
... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Tetracycline oral dosage forms. 520.2345 Section... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.2345 Tetracycline oral dosage forms....
... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Stanozolol oral dosage forms. 520.2150 Section 520...) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.2150 Stanozolol oral dosage forms....
... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sulfamethazine sodium oral dosage forms. 520.2261 Section 520.2261 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.2261 Sulfamethazine sodium oral dosage...
Brasselet, C; Duval, S
New oral anticoagulants constitute an important breakthrough for cardiologists and their patients. After reviewing their mechanism of action, their role in the context of interventional cardiology, particularly for patients with acute coronary syndromes, is discussed.
Pinto, Ian; Giri, Anshu; Arshad, Umbreen; Gajra, Ajeet
The advent of new oral anticoagulants (NOAC) has increased the armamentarium against thromboembolic diseases but has given rise to a conundrum on their reversal. NOAC's have comparable efficacy to traditional vitamin K antagonists with similar rates of major bleeding. However there is no standardized method for reversal of these agents and no specific antidote. This is of concern not only in acute bleeding episodes but also in clinical scenarios where emergency surgery is required. Recent studies have investigated reversal of dabigatran, rivaroxaban, and apixaban using prothrombin complex concentrates (PCC), recombinant factor VIIa, and in the case of dabigatran, a monoclonal antibody. These studies have been encouraging in showing improvement of bleeding times and blood loss in most models, especially with the use of PCCs and the dabigatran antibody. Of note the majority of common currently used coagulation assays may not correlate with clinical reversal. The management of overt bleeding with NOACs is difficult due to the lack of clinical trials. Current animal trials, case reports and hemostatic testing on human blood have shown some promise; provide guidance but warrant further investigation.
Alaali, Yathreb; Barnes, Geoffrey D; Froehlich, James B; Kaatz, Scott
Approximately 4.2 million patients in the United States are taking warfarin, making it the 11th most prescribed drug. Warfarin is primarily used for treatment of venous thromboembolic disease and stroke prevention in patients with atrial fibrillation and mechanical heart valves. Dentists frequently encounter anticoagulated patients and are faced with management decisions in these patients who require dental procedures. Observational studies suggest the risk of thrombosis if anticoagulation is suspended during dental procedures is higher than the risk of bleeding if anticoagulation is not suspended. Several groups now offer guidelines that recommend most minor dental procedures should be performed while on therapeutic warfarin. The recent approval of several new oral anticoagulants has introduced greater complexity to the management of the anticoagulated patient, and this narrative review will discuss current guidelines, the scientific underpinnings of the guidelines, and offer some practical suggestions for patients that are receiving the new agents.
Koenig-Oberhuber, V; Filipovic, M
In our daily anaesthetic practice, we are confronted with an increasing number of patients treated with either antiplatelet or anticoagulant agents. During the last decade, changes have occurred that make the handling of antithrombotic medication a challenging part of anaesthetic perioperative management. In this review, the authors discuss the most important antiplatelet and anticoagulant drugs, the perioperative management, the handling of bleeding complications, and the interpretation of some laboratory analyses related to these agents.
Scott, Alun; Gibson, John; Crighton, Alexander
Recently, new oral anticoagulants have been introduced as alternatives to warfarin. While national guidelines for treatment of dental patients taking warfarin as an anticoagulant are well-established, no such information is available for these novel therapeutic agents. At present, the local guidance available is contradictory between different health boards/health planning units, and liaison with the medical practitioner managing the individual patient's anticoagulation is imperative if any invasive procedure is proposed. This paper examines the available evidence regarding these drugs and sets out proposals for clinical guidance of dental practitioners treating these patients in primary dental care.
Belmar Vega, Lara; de Francisco, A L M; Bada da Silva, Jairo; Galván Espinoza, Luis; Fernández Fresnedo, Gema
Patients with chronic kidney disease (CKD) develop bleeding and thrombotic tendencies, so the indication of anticoagulation at the onset of atrial fibrillation (AF) is complex. AF is the most common chronic cardiac arrhythmia, and thromboembolism and ischemic stroke in particular are major complications. In recent years, new oral anticoagulant drugs have been developed, and they have shown superiority over the classical AVK in preventing stroke, systemic embolism and bleeding risk, constituting an effective alternative to those resources.
Introduction: For over 50 years, vitamin K antagonists such as warfarin (Aldocumar®) and acenocoumarol (Sintrom®) have been the gold standard for reducing the risk of cerebrovascular events. In the last 5 years alternative anticoagulants have been evaluated that act directly upon a concrete target within the coagulation cascade, thereby affording a more predictable anticoagulant effect. The present study offers an update on the new oral anticoagulants and reviews the implications referred to the dental care of patients administered these substances. Material and methods: An exhaustive PubMed-Medline and Cochrane Library search was made of the main alternatives to conventional oral anticoagulation, covering those studies published in English and Spanish over the last 10 years. Specialized textbooks and pharmaceutical catalogs were also consulted. A total of 184 articles were identified, of which 76 met the inclusion criteria. Results: The new oral anticoagulants dabigatran, rivaroxaban and apixaban are safe and effective, and offer a series of advantages, including rapid action, no need for constant monitoring, few drug and food interactions, and a broad therapeutic margin. These drugs are expensive, however, and some lack a specific antidote, while others must be administered twice a day. Regarding the dental treatment of patients receiving these drugs, suspension or modification of the background medication is not required when performing invasive dental procedures, except where indicated by the prescribing physician. Conclusions: The new oral anticoagulants do not pose significantly greater risks than conventional oral anticoagulants when providing invasive dental treatment, and their suspension is not strictly required in such situations. Key words:Dabigatran, rivaroxaban, apixaban, dental, hemostasis. PMID:24455094
Obamiro, Kehinde O.; Chalmers, Leanne; Bereznicki, Luke R. E.
Background Assessing and improving patients’ anticoagulation knowledge can lead to better treatment outcomes. While validated knowledge instruments exist for use in people taking warfarin, these tools are not necessarily applicable to patients taking direct-acting oral anticoagulants. Objective To develop and validate an oral anticoagulation knowledge instrument that is applicable to all oral anticoagulant medications. Methods Ten anticoagulation experts participated in the development of the Anticoagulation Knowledge Tool to ensure content validity. The knowledge instrument was administered to three groups of participants comprising of 44 pharmacists, 50 patients and 50 members of the general public. A subgroup of participants in the patient and pharmacist group were retested approximately 2–3 months after the initial testing. Statistical tests were conducted to determine the validity and reliability of the scale, and item analysis was used to determine the performance of individual questions. Results The 28-item instrument developed had a scale content validity index of 0.92, supporting content validity. The pharmacist group’s mean score was significantly higher than that of the patient group, and the patient group scored significantly higher than the general public group (94% vs 62% vs 20%, respectively; p<0.001), supporting construct validity. Internal consistency reliability was acceptable with a Cronbach’s α value of > 0.7 across the three groups, and the test–retest reliability was confirmed with a Pearson’s correlation coefficient of 0.72 and 0.78 for the pharmacist and patient groups, respectively. Conclusion The Anticoagulation Knowledge Tool is a valid and reliable instrument that can be used in routine clinical practice to assess patients’ anticoagulation knowledge. PMID:27351746
del Molino, Fátima; Gonzalez, Isabel; Saperas, Esteve
New oral direct anticoagulants agents are alternatives to warfarin for long-term anticoagulation in a growing number of patients that require long-term anticoagulation for atrial fibrillation, deep venous thrombosis and pulmonary embolism. These new agents with predictable pharmacokinetic and pharmacodynamics profiles offer a favorable global safety profile, but increased gastrointestinal bleeding compared to the vitamin K antagonists. Many gastroenterologists are unfamiliar and may be wary of these newer drugs, since Clinical experience is limited and no specific antidote is available to reverse their anticoagulant effect. In this article the risk of these new agents and, how to manage these agents in both the presence of acute gastrointestinal bleeding and in patients undergoing endoscopic procedures is reviewed.
Briongos Figuero, Sem; García Santos-Gallego, Carlos; Badimón, Juan José
For the last decades vitamin K antagonists have been the most effective anticoagulant treatment of atrial fibrillation. New molecules are being designed, mainly due to the great amount of disadvantages in the management of conventional anticoagulation. Dabigatran, rivaroxaban and apixaban will soon be available as an alternative to warfarin/acenocumarol. All of them have demonstrated to be non-inferior to warfarin in preventing stroke and systemic embolism, with even dabigatran 150 mg bid and apixaban being superior. They have also a lower risk of bleeding, especially regarding severe/fatal and intracranial hemorrhages. This is a real revolution. The advance of these new anticoagulants will be limited only by the higher cost, and will progressively become the protagonists of oral anticoagulation in patients with nonvalvular atrial fibrillation.
O'Connell, John Edward; Stassen, Leo F A
Anticoagulation therapy is used in several conditions to prevent or treat thromboembolism. Over the last 40 years, warfarin has been the oral anticoagulant of choice and has been considered the mainstay of treatment. However, its use is limited by a narrow therapeutic index and complex pharmacodynamics, necessitating regular monitoring and dose adjustments. Recently, two new oral anticoagulants--dabigatran etexilate (a direct thrombin inhibitor) and rivaroxiban (a factor Xa inhibitor)--have been approved for use in North America and Europe. Unlike warfarin, dabigatran and rivaroxiban are relatively small molecules that work as anticoagulants by targeting specific single steps of the coagulation cascade. Their advantages, relative to warfarin, include: predictable pharmacokinetics; limited food and drug interactions; rapid onset of action; and, short half-life. They require no monitoring. However, they lack a specific reversal agent. The number of patients taking dabigatran and rivaroxaban is increasing. Therefore, it is inevitable that dentists will be required to perform invasive procedures on this cohort of patients. This paper outlines the various properties of the new oral anticoagulants and the most recent guidelines regarding the management of these dental patients taking these medications.
... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Penicillin oral dosage forms. 520.1696 Section 520.1696 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1696 Penicillin...
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... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Dexamethasone oral dosage forms. 520.540 Section 520.540 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS §...
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... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Styrylpyridinium, diethylcarbamazine oral dosage forms. 520.2160 Section 520.2160 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... § 520.2160 Styrylpyridinium, diethylcarbamazine oral dosage forms....
... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Styrylpyridinium, diethylcarbamazine oral dosage forms. 520.2160 Section 520.2160 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... § 520.2160 Styrylpyridinium, diethylcarbamazine oral dosage forms....
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Sunkara, Tagore; Ofori, Emmanuel; Zarubin, Vadim; Caughey, Megan E.; Gaduputi, Vinaya; Reddy, Madhavi
Direct oral anticoagulants (DOACs) are in wide use among patients requiring both short- and long-term anticoagulation, mainly due to their ease of use and the lack of monitoring requirements. With growing use of DOACs, it is imperative that physicians be able to manage patients on these medications, especially in the perioperative period. We aim to provide guidance on the management of DOACs in the perioperative period. In this review, we performed an extensive literature search summarizing the management of patients on direct-acting anticoagulants in the perioperative period. A total of four direct-acting oral anticoagulants were considered appropriate for inclusion in this review. The drugs were dabigatran etexilate mesylate (Pradaxa), rivaroxaban (Xarelto), apixaban (Eliquis), and edoxaban (Savaysa). Management of patients on DOACs in the perioperative period involves an assessment of thromboembolic event risk while off anticoagulation compared to the relative risk of bleeding if such drug is continued. DOACs may not need to be discontinued in minor surgeries or procedures, and in major surgeries, they may be discontinued hours prior depending on drug pharmacokinetics and renal function of the patients. PMID:28008269
Saour, J N; Ali, H A; Mammo, L A; Sieck, J O
Over a 10-year period a uniform management plan for patients receiving long term oral anticoagulation therapy for prosthetic heart valves and needing dental procedures was instituted. Those undergoing dental extraction or gum hygiene in the presence of gross gum pathology (Group A) had their oral anticoagulation discontinued two days prior to the procedure which was carried out only if the INR was 1.5 or less on the day of the procedure. Patients who needed dental fillings or gum hygiene in the absence of gross gum pathology (Group B) continued their anticoagulation therapy and had these procedures completed provided the INR was 3.0 or less. The main outcome measured were valve thrombosis, thromboembolism and excessive bleeding requiring hospitalization and/or blood transfusion. In Group A, 240 procedures were carried out; 212 dental extractions and 28 dental hygiene in the presence of gross gum pathology. They had a brief period of under-anticoagulation (3-7 days) to an INR of 1.5 or less. In Group B, 156 procedures were performed. No patient developed valve thrombosis or thromboembolism. Two patients, both in Group A needed hospitalization for observation but no blood transfusion. This management plan was easy to implement. Patients needed one extra visit to the anticoagulation clinic within one week of the procedure. It was both safe and effective.
Diener, H C; Easton, J D; Hankey, G J; Hart, R G
In patients with atrial fibrillation (AF) oral anticoagulation with vitamin-K antagonists (warfarin, phenprocoumon) is effective both for primary and secondary stroke prevention yielding a 60-70% relative reduction in stroke risk compared with placebo, as well as a mortality reduction of 26 percent. Vitamin-K antagonists have a number of well documented shortcomings. Recently the results of randomised trials for three new oral anticoagulants that do not exhibit the limitations of vitamin-K antagonists have been published. These include direct factor Xa inhibitors (rivaroxaban and apixaban) and a direct thrombin inhibitor (dabigatran). The studies (RE-LY, ROCKET-AF, ARISTOTLE, AVERROES) provide promising results for the new agents, including higher efficacy and a significantly lower incidence of intracranial bleeds compared with warfarin or aspirin. The new drugs show similar results in secondary as well as in primary stroke prevention in patients with AF. Apixaban was demonstrated to be clearly superior to aspirin and had the same rate of major bleeding complications. Meta-analyses show that the novel anticoagulants are superior to warfarin for the reduction of stroke, major bleeding and intracranial bleeds. New anticoagulants add to the therapeutic options for patients with AF, and offer a number of advantages over warfarin, for both the clinician and patient, including a favorable bleeding profile and convenience of use. Aspirin is no longer an option in secondary stroke prevention in patients with atrial fibrillation. Consideration of these new anticoagulants will improve clinical decision making.
Whitworth, Maegan M; Haase, Krystal K; Fike, David S; Bharadwaj, Ravindra M; Young, Rodney B; MacLaughlin, Eric J
Background Scant literature exists evaluating utilization patterns for direct oral anticoagulants (DOACs). Objectives The primary objective was to assess DOAC prescribing in patients with venous thromboembolism (VTE) and nonvalvular atrial fibrillation (NVAF) in outpatient clinics. Secondary objectives were to compare utilization between family medicine (FM) and internal medicine (IM) clinics, characterize potentially inappropriate use, and identify factors associated with adverse events (AEs). Methods This was a retrospective cohort study of adults with NVAF or VTE who received a DOAC at FM or IM clinics between 10/19/2010 and 10/23/2014. Descriptive statistics were utilized for the primary aim. Fisher’s exact test was used to evaluate differences in prescribing using an adapted medication appropriateness index. Logistic regression evaluated factors associated with inappropriate use and AEs. Results One-hundred twenty patients were evaluated. At least 1 inappropriate criterion was met in 72 patients (60.0%). The most frequent inappropriate criteria were dosage (33.0%), duration of therapy (18.4%), and correct administration (18.0%). Apixaban was dosed inappropriately most frequently. There was no difference in dosing appropriateness between FM and IM clinics. The odds of inappropriate choice were lower with apixaban compared to other DOACs (odds ratio [OR]=0.088; 95% confidence interval [CI] 0.008–0.964; p=0.047). Twenty-seven patients (22.5%) experienced an AE while on a DOAC, and the odds of bleeding doubled with each inappropriate criterion met (OR=1.949; 95% CI 1.190–3.190; p=0.008). Conclusion Potentially inappropriate prescribing of DOACs is frequent with the most common errors being dosing, administration, and duration of therapy. These results underscore the importance of prescriber education regarding the appropriate use and management of DOACs. PMID:28331354
Marano, Giuseppe; Vaglio, Stefania; Pupella, Simonetta; Liumbruno, Giancarlo M.; Franchini, Massimo
Direct oral anticoagulants are at least as effective as vitamin K antagonists for the prevention and treatment of thromboembolism. Unfortunately, differently from vitamin K antagonists, they have the great drawback of lacking specific antidotes in the case of bleeding or emergency situations such as trauma, stroke requiring thrombolysis, and urgent surgery. The progressive development of antidotes for these new drugs, which, it is hoped, will become available in the near future, will allow better and safer management of the rapid reversal of their anticoagulant effect. PMID:27136433
Laroche, J-P; Schved, J-F
Vitamin K antagonists (VKA) and direct oral anticoagulants (DOACs) are now in competition. The companies are trying to replace VKA by DOACs, totally or at least greatly VKA should VKA disappear in favor of DOACs? There are still many questions about DOACs. The purpose of this article is to make a well-considered decision in this area. The aim is not to denigrate one or the other but to share things between these two families of anticoagulants. Physicians using these drugs must have a full knowledge about compared efficacy and safety. We feel necessary to increase distance between effective results of the clinical trials and industrial communication around DOACs.
Objective: Oral anticoagulants are widely administered to patients with atrial fibrillation in order to prevent the onset of cardiogenic embolisms. However, intracranial bleeding during anticoagulant therapy often leads to fatal outcomes. Accordingly, the use of novel oral anticoagulants (NOACs), which less frequently have intracranial bleeding as a complication, is expanding. A nationwide survey of intracranial bleeding and its prognosis in Japan reported that intracranial bleeding of advanced severity was not common after NOAC administration. In this report, two cases from our institute are presented. Patients: Case 1 was an 85-year-old man with a right frontal lobe hemorrhage while under dabigatran therapy. Case 2 was an 81-year-old man who had cerebellar hemorrhage while under rivaroxaban therapy. Result: In both patients, the clinical course progressed without aggravation of bleeding or neurological abnormalities once anticoagulant therapy was discontinued. Conclusion: These observations suggest that intracranial hemorrhage during NOAC therapy is easily controlled by discontinuation of the drug. NOAC administration may therefore be appropriate despite the risk of such severe complications. Further case studies that include a subgroup analysis with respect to each NOAC or patient background will be required to establish appropriate guidelines for the prevention of cardiogenic embolisms in patients with atrial fibrillation. PMID:27928459
Murakami, Takashi; Hina, Kazuyoshi; Higashiya, Shunichi; Kawamura, Hiroshi; Murakami, Masaaki; Kamikawa, Shigeshi; Komatsubara, Issei; Kusachi, Shozo
Background: Some patients with atrial fibrillation (AF) received underdoses of non-vitamin K antagonist oral anticoagulants (NOACs) in the real world. Underdosing is defined as administration of a dose lower than the manufacturer recommended dose. Objectives: To identify the efficacy and safety of underdosing NOACs as perioperative anticoagulation for atrial fibrillation ablation. Methods: We retrospectively analyzed patients who received rivaroxaban or dabigatran etexilate according to dosage: adjusted low dosage (reduced by disturbed renal function; n = 30), underdosage (n = 307), or standard dosage (n = 683). Non-vitamin K antagonist oral anticoagulants and dosing decisions were at the discretion of treating cardiologists. Results: Patients who received underdosed NOACs were older, more often female, and had lower body weight and lower renal function than those who received standard dosages. Activated clotting time at baseline in patients who received adjusted low dosage or underdosages was slightly longer than that in patients receiving standard dosages (156 ± 23, 151 ± 224, and 147 ± 24 seconds, respectively). Meaningful differences were not observed in other coagulation parameters. Adjusted low-, under-, and standard-dosing regimens did not differ in perioperative thromboembolic complications (0/30, 0.0%; 1/307, 0.3%; and 0/683, 0%, respectively) or major (0/30, 0.0%; 2/307, 0.6%; 3/683, 0.4%) and minor (1/30, 3.3%; 13/307, 4.2%; 25/683, 3.6%) bleeding episodes. When comparisons were performed for each NOAC, similar results were observed. Conclusions: With consideration of patient condition, age, sex, body weight, body mass index, and renal function, underdosing NOACs was effective and safe as a perioperative anticoagulation therapy for atrial fibrillation ablation. The therapeutic range of NOACs is potentially wider than manufacturer recommendations. PMID:28170360
Madan, Shivanshu; Shah, Shenil; Dale, Patrick; Partovi, Sasan
New oral anticoagulants (NOAC) serve as alternatives for patients currently using warfarin for the prevention and treatment of venous thromboembolic (VTE) disease. This article provides a brief summary of the clinical use of these drugs as well as a review of the landmark clinical trials which evaluated described their safety and efficacy. As more data becomes available, a fundamental understanding of these medications will be vital to cardiovascular practitioners managing patients with VTE. PMID:28123977
González Bárcenas, Martha L; Pérez Aisa, Ángeles
The development of novel antithrombotic therapy in the past few years and its prescription in patients with cardiovascular and circulatory disease has widened the spectrum of drugs that need to be considered when performing an endoscopic procedure. The balance between the thrombotic risk patients carry due to their medical history and the bleeding risk involved in endoscopic procedures should be thoroughly analyzed by Gastroenterologists. New oral anticoagulants (NOACs) impose an additional task. These agents, that specifically target factor IIa or Xa, do not dispose of an anticoagulation monitoring method nor have an antidote to revert their effect, just as with antiplatelet agents. Understanding the fundamental aspects of these drugs provides the necessary knowledge to determine the ideal period the antithrombotic therapy should be interrupted in order to perform the endoscopic procedure, offering maximum safety for patients and optimal results.
Spyropoulos, Alex C
The management of patients who need temporary interruption of chronic oral anticoagulant (OAC) therapy for an elective surgical or invasive procedure is problematic and complex. Patient and procedural risk factors for thrombosis and bleeding, anticoagulant-related risks of bleeding, and clinical consequences of a thrombotic or bleeding event need to be assessed and properly risk-stratified in the perioperative period. Certain procedures, such as dental, endoscopic, and cutaneous procedures, can be completed without discontinuing OAC, but most procedures with a high bleeding risk (including major surgeries) will necessitate temporary discontinuation of OAC. Bridging therapy with shorter-acting anticoagulants, such as heparin, for patients at intermediate to high risk of thromboembolism represents one strategy to maintain functional anticoagulation during this period. Large, prospective cohort studies and registries of patients on chronic OAC who underwent bridging therapy mostly with low-molecular-weight heparin have been completed recently. This paper reviews these clinical data on bridging therapy and provides an evidence-based perioperative management strategy for the at-risk patient on chronic OAC.
Atrial fibrillation treatment relies on anticoagulation therapy that reduces the risk of stroke. Vitamin K antagonists (VKA) were the only oral anticoagulant drugs for more than 50 years, but they are difficult to manage especially in the elderly. In France, VKA are the main cause of iatrogenic hospitalizations with about 17,000 hospitalizations per year and around 4,000 to 5,000 deaths per year. Pharmacologic properties of VKA, especially the narrow therapeutic margin explain the complexity of their management. Several studies have shown that patients treated with VKA were on average only 50% of the time with an INR in the therapeutic range. In other words, patients are, half of the time, either-under treated or over-treated. Within this framework, development of new oral anticoagulant drugs appeared necessary, in order to obtain drugs with larger therapeutic margin and a better risk/benefit profile than VKA. Three large randomized clinical trials including almost 50,000 patients with 20,000 subjects over 75 years old and 8,000 over 80 years old, show a better risk/benefit profile of the new oral anticoagulants (NOAC) than VKA, characterized by a 50% reduction of cerebral hemorrhages, 22% reduction of stroke and 12% reduction of total mortality. Meanwhile, their renal elimination and the lack of control of the biological efficacy need to be taken into account for their prescription. Renal failure (estimated glomerular filtration rate according to Cockcroft formula < 30 mL/min) contraindicates their use. Their half-life is shorter than that of VKA and the biological monitoring is not available, thus a good adherence to the treatment is important. Studies specifically conducted among geriatric older population with poly-pathologies and frail are therefore needed to evaluate tolerance of NOAC in real life conditions.
Wawrzyńska, L; Przedlacki, J; Hajduk, B; Tomkowski, W; Fijałkowska, A; Ostrowski, K; Torbicki, A
A broad spectrum of indications for low molecular weight heparin (LMWH) requires an assessment of side effects especially during prolonged administration. There are common risk factors for venous thromboembolism (VTE) and osteoporosis; heparin is "the drug of choice" for VTE treatment. The aim of our study was to assess the effect of treatment and prophylaxis with LMWH (enoxaparine sodium) and oral anticoagulant (acenocoumarol) for bone structure. Material consists of in- and outpatients. 49 densitometries were performed in 31 patients (in 15 cases double examination). We observed a decrease of bone mineral density in comparison to the initial examination in most cases: mean change of bone mass for examined areas was 3.05%.
da Silva, Rose M.F.L.
Atrial fibrillation is the most frequent arrhythmia in clinical practice, reaching 2% of the people in the world and is associated with systemic embolism. Thus, the use of anticoagulants is indicated if CHA2DS2-VASc score ≥2 or in patients with previous transient ischemic attack or stroke. For decades, warfarin, a vitamin K antagonist, was the only choice for chronic oral anticoagulation. Recently, novel oral anticoagulants (NOACs) have been introduced, offering similar (or better) effectiveness, safety, and convenience to the vitamin K antagonists. Dabigatran was the first NOAC approved and is a direct thrombin inhibitor. Rivaroxaban and apixaban are factor Xa inhibitors. They display rapid onset of action, more predictable of pharmacological profile, less interactions with other drugs, lack of significant effects in the diet, and less risk of intracranial hemorrhage than warfarin. Despite that dose adjustment is necessary for patients with chronic kidney disease or according to body weight, these new drugs do not require regular monitoring. There are recommendations for the start and follow-up therapy with NOACs, planning for cardioversion, ablation and surgical interventions and the management of bleeding. This article is a review of the major studies of the NOACs. The clinical use of these drugs in patients with non-valvular atrial fibrillation is presented. PMID:25470147
Ling, J; Gupta, V D
The stability of ethacrynic acid (2.5 mg/mL) in oral liquid dosage forms was investigated. Tablets in 0.05 M phosphate buffer (available commercially) in water were used to prepare the dosage forms. The effects of mannitol and sugar on the stability of ethacrynic acid were negligible. There was no change in the physical appearance of the oral liquid dosage forms or pH values during the study. There was, however, a new peak in the chromatogram from the products(s) of decomposition. An oral liquid dosage form of ethacrynic acid containing 0.05 M phosphate buffer and 10% mannitol was stable for 24 days when stored at 5 deg C and for only 3 days when stored at 25 deg C.
Crowther, Mark; Crowther, Mark A
The direct thrombin inhibitor dabigatran and the anti-Xa agents rivaroxaban, edoxaban, and apixaban are a new generation of oral anticoagulants. Their advantage over the vitamin K antagonists is the lack of the need for monitoring and dose adjustment. Their main disadvantage is currently the absence of a specific reversal agent. Dabigatran's, unlike the anti-Xa agents, absorption can be reduced by activated charcoal if administered shortly after ingestion and it can be removed from the blood with hemodialysis. Prothrombin complex concentrate, activated prothrombin complex concentrate, and recombinant factor VIIa all show some activity in reversing the anticoagulant effect of these drugs but this is based on ex vivo, animal, and volunteer studies. It is unclear, which, if any, of these drugs is the most suitable for emergency reversal. Three novel molecules (idarucizumab, andexanet, and PER977) may provide the most effective and safest way of reversal. These agents are currently in premarketing studies.
Garcia, David A
More than 4 years have passed since the first approval of a target-specific oral anticoagulant (TSOAC) in the United States, and the number of clinicians who have prescribed (or considered prescribing) one or more of these medications is increasing. Although these agents may, in properly selected patients, offer advantages over more traditional therapies, their lack of familiarity can be intimidating. Clinicians who are prescribing the TSOACs face a number of management questions not definitively answered by the registration trials. This chapter reviews some of these situations, including updated information on the periprocedural management of TSOACs and the latest evidence about how to best measure TSOAC effect. The lack of an antidote and other considerations that may be relevant when deciding between newer and more traditional anticoagulant medications are also discussed.
Vogt, M; Derendorf, H; Krämer, J; Junginger, H E; Midha, K K; Shah, V P; Stavchansky, S; Dressman, J B; Barends, D M
Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing prednisolone are reviewed. Data on its solubility, oral absorption, and permeability are not totally conclusive, but strongly suggest a BCS Class 1 classification. Prednisolone's therapeutic indications and therapeutic index, pharmacokinetics, and the possibility of excipient interactions were also taken into consideration. Available evidence indicates that a biowaiver for IR solid oral dosage forms formulated with the excipients tabulated in this article would be unlikely to expose patients to undue risks.
Wilson, S. Jo-Anne; Wells, Philip S.; Kovacs, Michael J.; Lewis, Geoffrey M.; Martin, Janet; Burton, Erica; Anderson, David R.
Background There is growing evidence that better outcomes are achieved when anticoagulation is managed by anticoagulation clinics rather than by family physicians. We carried out a randomized controlled trial to evaluate these 2 models of anticoagulant care. Methods We randomly allocated patients who were expected to require warfarin sodium for 3 months either to anticoagulation clinics located in 3 Canadian tertiary hospitals or to their family physician practices. We evaluated the quality of oral anticoagulant management by comparing the proportion of time that the international normalized ratio (INR) of patients receiving warfarin sodium was within the target therapeutic range ± 0.2 INR units (expanded therapeutic range) while they were managed in anticoagulation clinics as opposed to family physicians' care over 3 months. We measured the rates of thromboembolic and major hemorrhagic events and patient satisfaction in the 2 groups. Results Of the 221 patients enrolled, 112 were randomly assigned to anticoagulation clinics and 109 to family physicians. The INR values of patients who were managed by anticoagulation clinics were within the expanded therapeutic range 82% of the time versus 76% of the time for those managed by family physicians (p = 0.034). High-risk INR values (defined as being < 1.5 or > 5.0) were more commonly observed in patients managed by family physicians (40%) than in patients managed by anticoagulation clinics (30%, p = 0.005). More INR measurements were performed by family physicians than by anticoagulation clinics (13 v. 11, p = 0.001). Major bleeding events (2 [2%] v. 1 [1%]), thromboembolic events (1 [1%] v. 2 [2%]) and deaths (5 [4%] v. 6 [6%]) occurred at a similar frequency in the anticoagulation clinic and family physician groups respectively. Of the 170 (77%) patients who completed the patient satisfaction questionnaire, more were satisfied when their anticoagulant management was managed through anticoagulation clinics than by
Oprita, R; Oprita, B; Diaconescu, B; Bratu, MR; Berceanu, D
Anticoagulants are frequently used medications in diverse cardiovascular diseases. Their uses highly increase the risk of bleeding from upper and lower gastrointestinal sources, whether there is a classic vitamin K antagonist or a novel oral anticoagulant. Their interruption can promote procoagulation status with different thromboembolic accidents. Discontinuation of oral anticoagulants before the elective procedures is standardized but there are no guidelines for managing bleeding lesions of upper gastrointestinal tract concomitant with anticoagulation. Also, because some of the anticoagulants are new comers, there is no specific antidote, and so their anticoagulation effect cannot be antagonized fast in order to reduce the bleeding. Therefore, the endoscopic hemostasis must be definitive and efficient. This is a short review of the current management for the bleeding lesions of the upper gastrointestinal tract in patients taking oral anticoagulants. PMID:28255372
Expósito, Víctor; Seras, Miguel; Fernández-Fresnedo, Gema
Atrial fibrillation is a common finding in patients with chronic kidney disease (CKD), which increases markedly the embolism risk. The CHADS2 and HAS-BLED scales, used in the general population to assess the risk/benefit of oral anticoagulation (OAC), underestimate respectively the risk of embolism and haemorrhage in CKD, making it difficult to decide whether to use OAC or not. Based on the available evidence, it seems indicated to use OAC in stage 3 CKD, while it is controversial in advanced stages. New OAC such as dabigatran and rivaroxaban have been approved in stage 3 CKD but their role is still somewhat uncertain.
Baik, Seo Hyon; Hernandez, Inmaculada; Zhang, Yuting
BACKGROUND As alternatives to warfarin, 2 novel oral anticoagulants (NOACs), dabigatran and rivaroxaban, were approved in 2010 and 2011 to prevent stroke and other thromboembolic events in patients with atrial fibrillation. It is unclear how patient characteristics are associated with the initiation of anticoagulants. OBJECTIVE To evaluate how patient demographics, clinical characteristics, types of insurance, and patient out-of-pocket spending affect the initiation of warfarin and 2 NOACs—dabigatran and rivaroxaban. METHODS We used pharmacy claims data from a 5% random sample of Medicare beneficiaries to identify patients who were newly diagnosed with atrial fibrillation between October 1, 2010, and October 31, 2012, and who were prescribed an oral anticoagulant within 60 days of diagnosis. We identified key predictors of initiation of NOACs using a multinomial logistic regression model with generalized logit link. RESULTS Patients who were black and who had a history of acute myocardial infarction, stroke or transient ischemic attack, chronic kidney disease, or congestive heart failure were significantly associated with lower odds of receiving NOACs compared with warfarin. Age greater than 65 years, a history of hypertension, and use of nonsteroidal anti-inflammatory drugs were positively associated with the initiation of NOACs. Rivaroxaban was most likely to be initiated among women, followed by warfarin and dabigatran. Individuals receiving a low-income subsidy were more likely to initiate warfarin than NOACs, even though they paid little copayment. Individuals with supplemental Part D drug coverage, such as national Programs for All-Inclusive Care for the Elderly or employer-sponsored plans, were more likely to initiate NOACs compared with warfarin. CONCLUSIONS We found that race, sex, type of Part D plans, and some clinical conditions were associated with the initiation of NOACs relative to warfarin. But patient demographic and clinical characteristics did
Pelliccia, Francesco; Rollini, Fabiana; Marazzi, Giuseppe; Greco, Cesare; Gaudio, Carlo; Angiolillo, Dominick J; Rosano, Giuseppe
The combination of AF and coronary artery disease not only is a common clinical setting, it is also a complex setting to deal with anticoagulation and antiplatelet therapy, and it is associated with significantly higher mortality rates. Unfortunately, there are no sufficient data available to optimally guide clinical practice in such settings. This review focuses specifically on newer oral anticoagulants (NOACs) associated with dual antiplatelet therapy (DAPT) in patients with coronary artery disease undergoing percutaneous coronary intervention (PCI). There are no randomized studies comparing vitamin K antagonists and NOACs in patients with AF undergoing PCI either for acute coronary syndromes or for stable patients, i.e. those patients who have an indication to receive DAPT. Moreover, new antiplatelet agents such as ticagrelor and prasugrel have entered the market for acute coronary syndromes. So far, there are no large-scale randomized studies published evaluating these newer antiplatelet agents in patients with AF receiving either vitamin K antagonists or NOACs, adding to the uncertainty on how to use these antithrombotics in combination when both coronary artery disease (unstable or stable patients) and AF converge in a given patient. The lack of large outcome trials and the large number of possible combinations are reflected in the wide variety of practices in the real world. To date, given the lack of data, watchfulness when using NOACs as component of DAPT or triple oral antithrombotic therapy is warranted.
Numerous factors have been identified as risk factors for instability of oral anticoagulation, including variability in vitamin K intake. However few studies have directly tested the feasibility of manipulating dietary vitamin K to achieve stable oral anticoagulation. Recent findings from a rando...
... HUMAN SERVICES Food and Drug Administration 21 CFR Part 520 Oral Dosage Form New Animal Drugs; Phenylpropanolamine AGENCY: Food and Drug Administration, HHS. ACTION: Final rule. SUMMARY: The Food and Drug Administration (FDA) is amending the animal drug regulations to reflect approval of an original new animal...
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... HUMAN SERVICES Food and Drug Administration 21 CFR Part 520 Oral Dosage Form New Animal Drugs; Tiamulin... (FDA) is amending the animal drug regulations to reflect approval of a supplemental new animal drug application (NADA) filed by Novartis Animal Health US, Inc. The supplemental NADA provides for use of...
... HUMAN SERVICES Food and Drug Administration 21 CFR Part 520 Oral Dosage Form New Animal Drugs; Amprolium... (FDA) is amending the animal drug regulations to reflect approval of an original abbreviated new animal... requirements in 5 U.S.C. 801-808. List of Subjects in 21 CFR Part 520 Animal drugs. Therefore, under...
... HUMAN SERVICES Food and Drug Administration 21 CFR Part 520 Oral Dosage Form New Animal Drugs... Administration (FDA) is amending the animal drug regulations to reflect approval of a new animal drug application (NADA) filed by Novartis Animal Health US, Inc. The NADA provides for the veterinary prescription use...
Tong, Hoi Y; Dávila-Fajardo, Cristina Lucía; Borobia, Alberto M; Martínez-González, Luis Javier; Lubomirov, Rubin; Perea León, Laura María; Blanco Bañares, María J; Díaz-Villamarín, Xando; Fernández-Capitán, Carmen; Cabeza Barrera, José; Carcas, Antonio J
There is a strong association between genetic polymorphisms and the acenocoumarol dosage requirements. Genotyping the polymorphisms involved in the pharmacokinetics and pharmacodynamics of acenocoumarol before starting anticoagulant therapy would result in a better quality of life and a more efficient use of healthcare resources. The objective of this study is to develop a new algorithm that includes clinical and genetic variables to predict the most appropriate acenocoumarol dosage for stable anticoagulation in a wide range of patients. We recruited 685 patients from 2 Spanish hospitals and 1 primary healthcare center. We randomly chose 80% of the patients (n = 556), considering an equitable distribution of genotypes to form the generation cohort. The remaining 20% (n = 129) formed the validation cohort. Multiple linear regression was used to generate the algorithm using the acenocoumarol stable dosage as the dependent variable and the clinical and genotypic variables as the independent variables. The variables included in the algorithm were age, weight, amiodarone use, enzyme inducer status, international normalized ratio target range and the presence of CYP2C9*2 (rs1799853), CYP2C9*3 (rs1057910), VKORC1 (rs9923231) and CYP4F2 (rs2108622). The coefficient of determination (R2) explained by the algorithm was 52.8% in the generation cohort and 64% in the validation cohort. The following R2 values were evaluated by pathology: atrial fibrillation, 57.4%; valve replacement, 56.3%; and venous thromboembolic disease, 51.5%. When the patients were classified into 3 dosage groups according to the stable dosage (<11 mg/week, 11-21 mg/week, >21 mg/week), the percentage of correctly classified patients was higher in the intermediate group, whereas differences between pharmacogenetic and clinical algorithms increased in the extreme dosage groups. Our algorithm could improve acenocoumarol dosage selection for patients who will begin treatment with this drug, especially in
Sarich, Troy C; Seltzer, Jonathan H; Berkowitz, Scott D; Costin', James; Curnutte, John T; Gibson, C Michael; Hoffman, Maureane; Kaminskas, Edvardas; Krucoff, Mitchell W; Levy, Jerrold H; Mintz, Paul D; Reilly, Paul A; Sager, Philip T; Singer, Daniel E; Stockbridge, Norman; Weitz, Jeffrey I; Kowey, Peter R
This white paper provides a summary of presentations and discussions that were held at an Anticoagulant-Induced Bleeding and Reversal Agents Think Tank co-sponsored by the Cardiac Safety Research Consortium and the US Food and Drug Administration (FDA) at the FDA's White Oak Headquarters on April 22, 2014. Attention focused on a development pathway for reversal agents for the novel oral anticoagulants (NOACs). This is important because anticoagulation is still widely underused for stroke prevention in patients with atrial fibrillation. Undertreatment persists, although NOACs, in general, overcome some of the difficulties associated with anticoagulation provided by vitamin K antagonists. One reason for the lack of a wider uptake is the absence of NOAC reversal agents. As there are neither widely accepted academic and industry standards nor a definitive regulatory policy on the development of such reversal agents, this meeting provided a forum for leaders in the fields of cardiovascular clinical trials and cardiovascular safety to discuss the issues and develop recommendations. Attendees included representatives from pharmaceutical companies; regulatory agencies; end point adjudication specialist groups; contract research organizations; and active, academically based physicians. There was wide and solid consensus that NOACs overall offer improvements in convenience, efficacy, and safety compared with warfarin, even without reversal agents. Still, it was broadly accepted that it would be helpful to have reversal agents available for clinicians to use. Because it is not feasible to do definitive outcomes studies demonstrating a reversal agent's clinical benefits, it was felt that these agents could be approved for use in life-threatening bleeding situations if the molecules were well characterized preclinically, their pharmacodynamic and pharmacokinetic profiles were well understood, and showed no harmful adverse events in early human testing. There was also consensus
Vogel, T; Geny, B; Kaltenbach, G; Lang, P-O
Prescribing anticoagulant therapy when the CHA₂DS₂-VASc score is ≥ 1 prevents strokes secondary to non-valvular atrial fibrillation (AF). However, it is important to remember that whether the aged population has the highest risk of stroke in case of AF, under anticoagulant therapy this population is also at the highest risk of bleeding. Vitamin K antagonists were for decades the molecules of reference with benefits even after 75 years of age. The direct oral anticoagulants have overcome the biological constraints inherent to monitoring vitamin K antagonists and provide a more stable pharmacological action with a limited number of drug-drug interactions. However, the widespread use of these molecules in the older population remains controversial. In this review article, indications and modalities of administration of anticoagulant therapy in the elderly will be detailed and discussed on the basis of the most recent recommendations proposed in particular by the European Society of Cardiology. Particular attention will be paid to new oral anticoagulant therapies compared with vitamin K antagonists and antiplatelet agents.
Becker, C; Dressman, J B; Amidon, G L; Junginger, H E; Kopp, S; Midha, K K; Shah, V P; Stavchansky, S; Barends, D M
Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing pyrazinamide as the only active pharmaceutical ingredient (API) are reviewed. Pyrazinamide is BCS Class III, with linear absorption over a wide dosing range. The risk of bioinequivalence is estimated to be low. Depending on the definition used, pyrazinamide can be classified as a narrow therapeutic index (NTI) drug, which is usually a caveat to biowaiving but may be deemed acceptable if the Summary of Product Characteristics (SmPCs) of the test product stipulates the need for regular monitoring of liver function. It is concluded that a biowaiver can be recommended for IR solid oral dosage only when the test product (a) contains only excipients present in pyrazinamide IR solid oral drug products approved in ICH or associated countries, (b) these excipients are present in amounts normally used in IR solid oral dosage forms, (c) the test product is very rapidly dissolving, (d) the SmPC of the test product indicates the need for monitoring of the patient's liver function.
Cafolla, A; Melizzi, R; Baldacci, E; Pignoloni, P; Dragoni, F; Campanelli, M; Caraccini, R; Foà, R
The demand for oral anticoagulant therapy (OAT) has constantly increased during the last ten years with an extended use of computer assistance. Many mathematical algorithms have been projected to suggest doses and time to next visit for patients on OAT. We designed a new algorithm: "Zeus". A "before-after" study was planned to compare the efficacy and safety of this algorithm dosing OAT with manual dosage decided by the same expert physicians according to the target of International Normalized Ratio (INR). The study analysed data of 1876 patients managed with each of the two modalities for eight months, with an interval of two years between them. The aim was to verify the increased quality of therapy by time spent in INR target and efficiency and safety of Zeus algorithm. Time in therapeutic range (TTR) was significantly (p < 0.0001) higher during the algorithm dosing period in comparison with the TTR during manual management period (62.3% vs 50.3%). The number of PT/INR tests above 5 was significantly (p < 0.001) reduced by algorithm suggested prescriptions in comparison with manual those (254 vs 537 times). The anticoagulant drug amount prescribed according to the algorithm suggestions was significantly (p < 0.0001) lower than that of the manual method. The number of clinical events observed in patients during the algorithm management time was significantly (p < 0.05) lower than that in those managed with the manual dosage. This study confirms the clinical utility of the computer-assisted OAT and shows the efficacy and safety of the Zeus algorithm.
Koeppe, Marcelle O; Cristofoletti, Rodrigo; Fernandes, Eduardo F; Storpirtis, Silvia; Junginger, Hans E; Kopp, Sabine; Midha, Kamal K; Shah, Vinod P; Stavchansky, Salomon; Dressman, Jennifer B; Barends, Dirk M
Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing levofloxacin as the only active pharmaceutical ingredient (API) are reviewed. According to the current Biopharmaceutics Classification System, levofloxacin can be assigned to Class I. No problems with BE of IR levofloxacin formulations containing different excipients and produced by different manufacturing methods have been reported and hence the risk of bioinequivalence caused by these factors appears to be low. In addition, levofloxacin has a wide therapeutic index. On the basis of this evidence, a biowaiver is recommended for IR solid oral dosage forms containing levofloxacin as the single API provided that (a) the test product contains only excipients present in IR levofloxacin drug products that have been approved in International Conference on Harmonization (ICH) or associated countries and which have the same dosage form; (b) both the test and comparator dosage form are "very rapidly dissolving" or "rapidly dissolving" with similarity of the dissolution profiles demonstrated at pH 1.2, 4.5, and 6.8; and (c) if the test product contains polysorbates, it should be both qualitatively and quantitatively identical to its comparator in terms of polysorbate content.
Vogt, M; Derendorf, H; Krämer, J; Junginger, H E; Midha, K K; Shah, V P; Stavchansky, S; Dressman, J B; Barends, D M
Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing prednisone are reviewed. Due to insufficient data prednisone cannot be definitively classified according to the current Biopharmaceutics Classification System (BCS) criteria as both the solubility and the permeability of prednisone are on the borderline of the present criteria of BCS Class I. Prednisone's therapeutic indications and therapeutic index, pharmacokinetics and the possibility of excipient interactions were also taken into consideration. Available evidence indicates that a biowaiver for IR solid oral dosage forms formulated with the excipients tabulated in this article would be unlikely to expose patients to undue risks.
... Solid Oral Dosage Form Drug Products for Anticounterfeiting; Availability AGENCY: Food and Drug... Oral Dosage Form Drug Products for Anticounterfeiting.'' This guidance provides recommendations on... Identifiers Into Solid Oral Dosage Form Drug Products for Anticounterfeiting.'' For the purpose of...
... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Lincomycin hydrochloride monohydrate oral dosage... HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1263 Lincomycin hydrochloride monohydrate oral dosage forms....
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... 21 Food and Drugs 5 2011-04-01 2011-04-01 false Imprinting of solid oral dosage form drug products... AS SAFE AND EFFECTIVE AND NOT MISBRANDED General Provisions § 330.3 Imprinting of solid oral dosage form drug products. A requirement to imprint an identification code on solid oral dosage form...
... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Imprinting of solid oral dosage form drug products... AS SAFE AND EFFECTIVE AND NOT MISBRANDED General Provisions § 330.3 Imprinting of solid oral dosage form drug products. A requirement to imprint an identification code on solid oral dosage form...
Isnard, Richard; Bauer, Fabrice; Cohen-Solal, Alain; Damy, Thibaud; Donal, Erwan; Galinier, Michel; Hagège, Albert; Jourdain, Patrick; Leclercq, Christophe; Sabatier, Rémi; Trochu, Jean-Noël; Cohen, Ariel
Thromboembolism contributes to morbidity and mortality in patients with heart failure (HF), and atrial fibrillation (AF) is one of the main factors promoting this complication. As they share many risk factors, HF and AF frequently coexist, and patients with both conditions are at a particularly high risk of thromboembolism. Non-vitamin K antagonist oral anticoagulants (NOACs) are direct antagonists of thrombin (dabigatran) and factor Xa (rivaroxaban, apixaban and edoxaban), and were designed to overcome the limitations of vitamin K antagonists. Compared with warfarin in non-valvular AF, NOACs demonstrated non-inferiority with better safety, most particularly for intracranial haemorrhages. Therefore, the European Society of Cardiology guidelines recommend NOACs for most patients with non-valvular AF. Subgroups of patients with both AF and HF from the pivotal studies investigating the safety and efficacy of NOACs have been analysed and, for each NOAC, results were similar to those of the total analysis population. A recent meta-analysis of these subgroups has confirmed the better efficacy and safety of NOACs in patients with AF and HF - particularly the 41% decrease in the incidence of intracranial haemorrhages. The prothrombotic state associated with HF suggests that patients with HF in sinus rhythm could also benefit from treatment with NOACs. However, in the absence of clinical trial data supporting this indication, current guidelines do not recommend anticoagulant treatment of patients with HF in sinus rhythm. In conclusion, recent analyses of pivotal studies support the use of NOACs in accordance with their indications in HF patients with non-valvular AF.
Becker, C; Dressman, J B; Junginger, H E; Kopp, S; Midha, K K; Shah, V P; Stavchansky, S; Barends, D M
Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of new multisource and reformulated immediate release (IR) solid oral dosage forms containing rifampicin as the only Active Pharmaceutical Ingredient (API) are reviewed. Rifampicin's solubility and permeability, its therapeutic use and index, pharmacokinetics, excipient interactions and reported BE/bioavailability (BA) problems were taken into consideration. Solubility and absolute BA data indicate that rifampicin is a BCS Class II drug. Of special concern for biowaiving is that many reports of failure of IR solid oral dosage forms of rifampicin to meet BE have been published and the reasons for these failures are yet insufficiently understood. Moreover, no reports were identified in which in vitro dissolution was shown to be predictive of nonequivalence among products. Therefore, a biowaiver based approval of rifampicin containing IR solid oral dosage forms cannot be recommended for either new multisource drug products or for major scale-up and postapproval changes (variations) to existing drug products.
Petruševska, Marija; Berglez, Sandra; Krisch, Igor; Legen, Igor; Megušar, Klara; Peternel, Luka; Abrahamsson, Bertil; Cristofoletti, Rodrigo; Groot, D W; Kopp, Sabine; Langguth, Peter; Mehta, Mehul; Polli, James E; Shah, Vinod P; Dressman, Jennifer
Literature and experimental data relevant for the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing levetiracetam are reviewed. Data on solubility and permeability suggest that levetiracetam belongs to class I of the biopharmaceutical classification system (BCS). Levetiracetam's therapeutic use, its wide therapeutic index, and its favorable pharmacokinetic properties make levetiracetam a valid candidate for the BCS-based biowaiver approach. Further, no BE studies with levetiracetam IR formulations in which the test formulation failed to show BE with the comparator have been reported in the open literature. On the basis of the overall evidence, it appears unlikely that a BCS-based biowaiver approach for levetiracetam IR solid oral dosage forms formulated with established excipients would expose patients to undue risks. Thus, the BCS-based biowaiver approach procedure is recommended for IR solid oral dosage form containing levetiracetam, provided the excipients in the formulation are also present in products that have been approved in countries belonging to or associated with the International Committee on Harmonization and are used in their usual quantities, and provided the dissolution profiles of the test and reference product comply with the current requirements for BCS-based biowaivers.
Pandya, Ekta Y; Bajorek, Beata
The role of the direct oral anticoagulants (DOACs) in practice has been given extensive consideration recently, albeit largely from the clinician's perspective. However, the effectiveness and safety of using anticoagulants is highly dependent on the patient's ability to manage and take these complex, high-risk medicines. This structured narrative review explores the published literature to identify the factors underpinning patients' non-adherence to anticoagulants in atrial fibrillation (AF), and subsequently contemplates to what extent the DOACs might overcome the known challenges with traditional warfarin therapy. This review comprised a two-tier search of various databases and search platforms (CINAHL, Cochrane, Current Contents Connect, EMBASE, MEDLINE Ovid, EBSCO, PubMed, Google, Google Scholar) to yield 47 articles reporting patients perspectives on, and patients adherence to, anticoagulant therapy. The findings from the literature were synthesised under five interacting dimensions of adherence: therapy-related factors, patient-related factors, condition-related factors, social-economic factors and health system factors. Factors negatively affecting patients' day-to-day lives (especially regular therapeutic drug monitoring, dose adjustments, dietary considerations) predominantly underpin a patient's reluctance to take warfarin therapy, leading to non-adherence. Other patient-related factors underpinning non-adherence include patients' perceptions and knowledge about the purpose of anticoagulation; understanding of the risks and benefits of therapy; socioeconomic status; and expectations of care from health professionals. In considering these findings, it is apparent that the DOACs may overcome some of the barriers to traditional warfarin therapy at least to an extent, particularly the need for regular monitoring, frequent dose adjustment and dietary considerations. However, their high cost, twice-daily dosing and gastrointestinal adverse effects may present
Spivak, Inna E
Anticoagulation is an important strategy for the prevention of stroke associated with atrial fibrillation. Development of new oral agents has created a need to educate nurses to administer these medications and provide patient education.
Children generally reject taking medicine which does not have a favorable shape, taste, flavor, etc. However, if a child who needs to take a medicine, rejects taking it, he might never recover from his condition. When a child is unable to take medicine orally, it is intravenously administered, and he and his caregivers then may experience stress. Syrups and suspensions are considered as favorable types of dosage forms in which to orally administer medicine to infants and children. However, they may have disadvantages such as solubility, a bad taste, portability problems or required refrigerator storage. World Health Organization (WHO) currently favors that infants and children be treated with oral solid medicines. New oral solid tablets, such as a mini-tablet, instead of liquid medicines are proposed for this group, however, there are a few reports that mini-tablets are suitable for infants and children. Palatability is one of the main elements of patient acceptability of an oral pediatric medicine. Palatability is defined as the overall appreciation of an oral medicinal product in relation to its smell, taste, aftertaste and feeling in the mouth. Design of the formulation of an oral pediatric medicine should be considered together with its palatability.
Sherwood, Matthew W.; Becker, Richard C.
Atrial fibrillation is a common arrhythmia. One of the important aspects of the management of atrial fibrillation is stroke prevention. Warfarin has been the longstanding anticoagulant used for stroke prevention in patients with atrial fibrillation. There are now three novel oral anticoagulants, which have been studied in randomized controlled trials and subsequently approved by the Federal Drug Administration for stroke prevention in patients with atrial fibrillation. Special patient populations, including renal insufficiency, elderly, prior stroke, and extreme body weights, were represented to varying degrees in the clinical trials of the novel oral anticoagulants. Furthermore, there is variation in the pharmacokinetics and pharmacodynamics of each anticoagulant, which affect the patient populations differently. Patients and clinicians are faced with the task of selecting among the available anticoagulants, and this review is designed to be a tool for clinical decision-making. PMID:23846737
Miranda, M; Martinez, L S; Franco, R; Forte, V; Barlattani, A; Bollero, P
The oral anticoagulant therapy is used for the cure and the prevention of thromboembolic diseases. In the last fifty years the warfarin has been considered the oral anticoagulant of choice. However, its use is limited by a narrow therapeutic index and by a complex pharmacodynamics, which requires regular adjustments and monitoring of the dose. Recently, three new oral anticoagulant - dabigatran etexilato (direct thrombin inhibitor), rivaroxaban and apixaban (Xa factor direct inhibitor) - have been approved for use in europe. Increasing the number of patients taking these drugs, it is important that the dentist knows these new oral anticoagulants, their indications and methods of action, in particular for the management of patients, who require invasive treatments. With regard to the management of the patient threated with the new oral anticoagulants (NAO), there have been new significant changes in the procedure compared to the one followed by patients treated with warfarin. This led to the development of new guidelines that the dentist has to follow in order to ensure a safe and appropriate dental treatment and reduce any postoperative complications. The aim of this work is to evaluate the effectiveness of the new oral anticoagulants compared to warfarin, especially in terms of risks of bleeding events and intra and postoperative complications, in patients requiring multiple dental extractions.
MIRANDA, M.; MARTINEZ, L.S.; FRANCO, R.; FORTE, V.; BARLATTANI, A.; BOLLERO, P.
SUMMARY The oral anticoagulant therapy is used for the cure and the prevention of thromboembolic diseases. In the last fifty years the warfarin has been considered the oral anticoagulant of choice. However, its use is limited by a narrow therapeutic index and by a complex pharmacodynamics, which requires regular adjustments and monitoring of the dose. Recently, three new oral anticoagulant – dabigatran etexilato (direct thrombin inhibitor), rivaroxaban and apixaban (Xa factor direct inhibitor) – have been approved for use in europe. Increasing the number of patients taking these drugs, it is important that the dentist knows these new oral anticoagulants, their indications and methods of action, in particular for the management of patients, who require invasive treatments. With regard to the management of the patient threated with the new oral anticoagulants (NAO), there have been new significant changes in the procedure compared to the one followed by patients treated with warfarin. This led to the development of new guidelines that the dentist has to follow in order to ensure a safe and appropriate dental treatment and reduce any postoperative complications. The aim of this work is to evaluate the effectiveness of the new oral anticoagulants compared to warfarin, especially in terms of risks of bleeding events and intra and postoperative complications, in patients requiring multiple dental extractions. PMID:28042443
Krasny, Marta; Krasny, Kornel; Fiedor, Piotr
Cardiovascular conditions, apart from neoplastic diseases, remain the major cause of death in developed countries; therefore, the number of patients receiving oral anticoagulants is constantly increasing. Anticoagulant therapy considerably reduced mortality in patients with history of myocardial infarction among others. Although many interventions may be performed without withdrawal of the anticoagulant and tooth extraction was qualified as a procedure of low hemorrhage risk, a majority of dentists refer the patient to a cardiologist several days before the elective tooth extraction to withdraw anticoagulants. The aim of the study was to evaluate the efficacy and safety of bone wax used to stop bleeding after dental procedures in a group of patients on chronic anticoagulant therapy and find an answer to a question, whether it is justified to temporarily withdraw anticoagulants for this type of procedures. The study involved 176 patients on chronic anticoagulant therapy undergoing tooth extraction (154 subjects) or surgical extraction of a retained tooth (48 subjects). After the procedure, in each case the alveolus was filled with bone wax to stop bleeding. In all patients involved in the study bleeding from the alveolus was successfully stopped during the procedure. None of the subjects reported increased bleeding from the operational site after coming back home. Bone wax is a good, efficient, and safe material to block bleeding from the alveolus following tooth extractions, also in patients on chronic anticoagulant therapy. The study demonstrated that withdrawal or adjustment of anticoagulant therapy is not necessary before an elective tooth extraction.
Nutescu, Edith; Chuatrisorn, Ittiporn; Hellenbart, Erika
Clinicians and patients around the world have been intrigued by the concept of developing an oral anticoagulant with a broad therapeutic window and few drug and dietary interactions that can be administered at fixed doses with no or minimal monitoring. The recently approved oral direct thrombin inhibitor dabigatran, along with the emerging oral anti-factor Xa inhibitors, rivaroxaban, apixaban, and edoxaban, have been developed to address many of the shortcomings of warfarin therapy. As warfarin is associated with extensive food and drug interactions, there is also a need to consider such interactions with the new oral anticoagulants. While to date few drug and dietary interactions have been reported with the new oral anticoagulants, it is still early in their development and clinical use cycle. Pharmacokinetic and pharmacodynamic profiles will have to be closely accounted for when determining the likelihood of a potential drug interaction prior to therapy initiation. As the list of drugs and supplements that interact with warfarin is continuously expanding, and the knowledge on drug interactions with the novel oral anticoagulants is still in its infancy, clinicians need to be vigilant when initiating any of these agents or when any changes in the patient's medication profile occur and perform a close screening for potential drug and dietary interactions. The objective of this paper is to give an update on drug and dietary interactions with warfarin and the novel oral anticoagulants, dabigatran, rivaroxaban, apixaban, and edoxaban.
Granero, G E; Longhi, M R; Becker, C; Junginger, H E; Kopp, S; Midha, K K; Shah, V P; Stavchansky, S; Dressman, J B; Barends, D M
Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing acetazolamide are reviewed. Acetazolamide's solubility and permeability characteristics according to the Biopharmaceutics Classification System (BCS), as well as its therapeutic use and therapeutic index, its pharmacokinetic properties, data related to the possibility of excipient interactions and reported BE/bioavailability (BA) problems are taken into consideration. The available data on solubility, on oral absorption and permeability are not sufficiently conclusive to classify acetazolamide with certainty. Taking a conservative approach, no biowaiver is considered justified for the registration of new multisource drug products. However, SUPAC level 1 and level 2 postapproval changes and most EU Type I variations can be approved waiving in vivo BE studies.
Granero, G E; Longhi, M R; Mora, M J; Junginger, H E; Midha, K K; Shah, V P; Stavchansky, S; Dressman, J B; Barends, D M
Literature and new experimental data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing furosemide are reviewed. The available data on solubility, oral absorption, and permeability are sufficiently conclusive to classify furosemide into Class IV of the Biopharmaceutics Classification System (BCS). Furosemide's therapeutic use and therapeutic index, its pharmacokinetic properties, data related to the possibility of excipient interactions and reported BE/bioavailability (BA) problems are also taken into consideration. In view of the data available, it is concluded that the biowaiver procedure cannot be justified for either the registration of new multisource drug products or major postapproval changes (variations) to existing drug products.
Başaran, Özcan; Dogan, Volkan; Beton, Osman; Tekinalp, Mehmet; Aykan, Ahmet Cağri; Kalaycioğlu, Ezgi; Bolat, Ismail; Taşar, Onur; Şafak, Özgen; Kalcik, Macit; Yaman, Mehmet; İnci, Sinan; Altintaş, Bernas; Kalkan, Sedat; Kirma, Cevat; Biteker, Murat
Abstract This study aimed to investigate the potential misuse of novel oral anticoagulants (NOACs) and the physicians’ adherence to current European guideline recommendations in real-world using a large dataset from Real-life Multicenter Survey Evaluating Stroke Prevention Strategies in Turkey (RAMSES Study). RAMSES study is a prospective, multicenter, nationwide registry (ClinicalTrials.gov identifier NCT02344901). In this subgroup analysis of RAMSES study, patients who were on NOACs were classified as appropriately treated (AT), undertreated (UT), and overtreated (OT) according to the European Society of Cardiology (ESC) guidelines. The independent predictors of UT and OT were determined by multivariate logistic regression. Of the 2086 eligible patients, 1247 (59.8%) received adequate treatment. However, off-label use was detected in 839 (40.2%) patients; 634 (30.4%) patients received UT and 205 (9.8%) received OT. Independent predictors of UT included >65 years of age, creatinine clearance ≥50 mL/min, urban living, existing dabigatran treatment, and HAS-BLED score of <3, whereas that of OT were creatinine clearance <50 mL/min, ongoing rivaroxaban treatment, and HAS-BLED score of ≥3. The suboptimal use of NOACs is common because of physicians’ poor compliance to the guideline recommendations in patients with nonvalvular atrial fibrillation (NVAF). Older patients who were on dabigatran treatment with good renal functions and low risk of bleeding were at risk of UT, whereas patients who were on rivaroxaban treatment with renal impairment and high risk of bleeding were at risk of OT. Therefore, a greater emphasis should be given to prescribe the recommended dose for the specified patients. PMID:27583892
Cristofoletti, Rodrigo; Nair, Anita; Abrahamsson, Bertil; Groot, D W; Kopp, Sabine; Langguth, Peter; Polli, James E; Shah, Vinod P; Dressman, Jennifer B
Literature data pertaining to the decision to allow a waiver of in vivo bioequivalence testing for the approval of immediate-release (IR) solid oral dosage forms containing efavirenz as the only active pharmaceutical ingredient (API) are reviewed. Because of lack of conclusive data about efavirenz's permeability and its failure to comply with the "high solubility" criteria according to the Biopharmaceutics Classification System (BCS), the API can be classified as BCS Class II/IV. In line with the solubility characteristics, the innovator product does not meet the dissolution criteria for a "rapidly dissolving product." Furthermore, product variations containing commonly used excipients or in the manufacturing process have been reported to impact the rate and extent of efavirenz absorption. Despite its wide therapeutic index, subtherapeutic levels of efavirenz can lead to treatment failure and also facilitate the emergence of efavirenz-resistant mutants. For all these reasons, a biowaiver for IR solid oral dosage forms containing efavirenz as the sole API is not scientifically justified for reformulated or multisource drug products.
Gittings, Sally; Turnbull, Neil; Roberts, Clive J; Gershkovich, Pavel
Conventional adult dosage forms are often not suitable for the paediatric and geriatric populations due to either swallowing difficulties or patient repulsion and a requirement for tailored dosing to individual compliance or physiological needs. Alternative formulations are available; however these often require the incorporation of more complex taste masking techniques. One approach to taste masking is to reduce contact between the bitter Active Pharmaceutical Ingredient (API) and oral cavity taste bud regions. This is achieved by hindering release in the oral cavity, or including competitive inhibition of bitter sensation for example by using flavours or sweeteners. There may also be other sensational complications from the API such as residual burning, reflux or metallic taste sensations to deal with. In vitro dissolution testing is employed to elucidate taste masking capability by quantifying release of the drug in simulated oral cavity conditions. Dissolution testing approaches may also be used to potentially predict or quantify the effect of the taste masking technique on the resultant pharmacokinetic profile. The present review investigates the anatomy and physiology of the oral cavity and current approaches to taste masking. In vitro dissolution methodologies adopted in the evaluation of taste masked formulations are discussed for their relative merits and drawbacks. A vast array of methodologies has been employed, with little agreement between approaches, and a lack of biorelevance. Future directions in dissolution methodology such as TNO Intestinal Model (TIM) and the Artificial Stomach and Duodenum model (ASD) are also discussed.
Di Minno, Alessandro; Frigerio, Beatrice; Spadarella, Gaia; Ravani, Alessio; Sansaro, Daniela; Amato, Mauro; Kitzmiller, Joseph P; Pepi, Mauro; Tremoli, Elena; Baldassarre, Damiano
The most commonly prescribed oral anticoagulants worldwide are the vitamin K antagonists (VKAs) such as warfarin. Factors affecting the pharmacokinetics of VKAs are important because deviations from their narrow therapeutic window can result in bleedings due to over-anticoagulation or thrombosis because of under-anticoagulation. In addition to pharmacodynamic interactions (e.g., augmented bleeding risk for concomitant use of NSAIDs), interactions with drugs, foods, herbs, and over-the-counter medications may affect the risk/benefit ratio of VKAs. Direct oral anticoagulants (DOACs) including Factor Xa inhibitors (rivaroxaban, apixaban and edoxaban) and thrombin inhibitor (dabigatran) are poised to replace warfarin. Phase-3 studies and real-world evaluations have established that the safety profile of DOACs is superior to those of VKAs. However, some pharmacokinetic and pharmacodynamic interactions are expected. Herein we present a critical review of VKAs and DOACs with focus on their potential for interactions with drugs, foods, herbs and over-the-counter medications.
Egea-Guerrero, J J; Quintana Díaz, M
The high incidence of trauma, especially in elderly people anticoagulated with new oral anticoagulants (NOAs), has become a major challenge, particularly in critical situations with life-threatening bleeding. Under these circumstances, urgent NOA reversion becomes mandatory. Prothrombin complex has become a frequent indication in critical situations in which rapid reversal of anticoagulation is needed and where the use of fresh frozen plasma is limited. This study offers our point of view regarding the usefulness of NOAs, not only in the prevention of cardioembolic events but also as regards their emergent reversion in cases of severe bleeding associated to trauma.
Shohin, Igor E; Kulinich, Julia I; Ramenskaya, Galina V; Abrahamsson, Bertil; Kopp, Sabine; Langguth, Peter; Polli, James E; Shah, Vinod P; Groot, D W; Barends, Dirk M; Dressman, Jennifer B
Literature and experimental data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing piroxicam in the free acid form are reviewed. Piroxicam solubility and permeability, its therapeutic use and therapeutic index, pharmacokinetic properties, data related to the possibility of excipient interactions and reported BE/bioavailability (BA), and corresponding dissolution data are taken into consideration. The available data suggest that according to the current biopharmaceutics classification system (BCS) and all current guidances, piroxicam would be assigned to BCS Class II. The extent of piroxicam absorption seems not to depend on manufacturing conditions or excipients, so the risk of bioinequivalence in terms of area under the curve (AUC) is very low, but the rate of absorption (i.e., BE in terms of Cmax ) can be affected by the formulation. Current in vitro dissolution methods may not always reflect differences in terms of Cmax for BCS Class II weak acids; however, minor differences in absorption rate of piroxicam would not subject the patient to unacceptable risks: as piroxicam products may be taken before or after meals, the rate of absorption cannot be considered crucial to drug action. Therefore, a biowaiver for IR piroxicam solid oral dosage form is considered feasible, provided that (a) the test product contains only excipients, which are also present in IR solid oral drug products containing piroxicam, which have been approved in ICH or associated countries, for instance, those presented in Table 3 of this paper; (b) both the test and comparator drug products dissolve 85% in 30 min or less at pH 1.2, 4.5, and 6.8; and (c) the test product and comparator show dissolution profile similarity in pH 1.2, 4.5, and 6.8. When not all of these conditions can be fulfilled, BE of the products should be established in vivo.
Becker, C; Dressman, J B; Amidon, G L; Junginger, H E; Kopp, S; Midha, K K; Shah, V P; Stavchansky, S; Barends, D M
Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing isoniazid as the only active pharmaceutical ingredient (API) are reviewed. Isoniazid's solubility and permeability characteristics according to the Biopharmaceutics Classification System (BCS), as well as its therapeutic use and therapeutic index, its pharmacokinetic properties, data related to the possibility of excipient interactions and reported BE/bioavailability (BA) problems were taken into consideration. Isoniazid is "highly soluble" but data on its oral absorption and permeability are inconclusive, suggesting this API to be on the borderline of BCS Class I and III. For a number of excipients, an interaction with the permeability is extreme unlikely, but lactose and other deoxidizing saccharides can form condensation products with isoniazid, which may be less permeable than the free API. A biowaiver is recommended for IR solid oral drug products containing isoniazid as the sole API, provided that the test product meets the WHO requirements for "very rapidly dissolving" and contains only the excipients commonly used in isoniazid products, as listed in this article. Lactose and/or other deoxidizing saccharides containing formulations should be subjected to an in vivo BE study.
Arnal, J; Gonzalez-Alvarez, I; Bermejo, M; Amidon, G L; Junginger, H E; Kopp, S; Midha, K K; Shah, V P; Stavchansky, S; Dressman, J B; Barends, D M
Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing (biowaiver) for the approval of immediate release (IR) solid oral dosage forms containing aciclovir are reviewed. Aciclovir therapeutic use and therapeutic index, pharmacokinetic properties, data related to the possibility of excipient interactions and reported BE/bioavailability (BA) studies were also taken into consideration in order to ascertain whether a biowaiver can be recommended. According to the Biopharmaceutics Classification System (BCS) and considering tablet strengths up to 400 mg, aciclovir would be BCS Class III. However, in some countries also 800 mg tablets are available which fall just within BCS Class IV. Aciclovir seems not to be critical with respect to a risk for bioinequivalence, as no examples of bioinequivalence have been identified. It has a wide therapeutic index and is not used for critical indications. Hence, if: (a) the test product contains only excipients present in aciclovir solid oral IR drug products approved in ICH or associated countries, for instance as presented in this article; and (b) the comparator and the test product both are very rapidly dissolving, a biowaiver for IR aciclovir solid oral drug products is considered justified for all tablet strengths.
Bosch, Luis Ángel Bermúdez
Warfarin is the current standard of care in oral anticoagulation therapy. It is commonly prescribed to treat venous thromboembolism, pulmonary embolism, acute myocardial infarction, and to decrease the risk of stroke in atrial fibrillation. Warfarin therapy is challenging because of marked and often unpredictable inter-individual dosing variations that effectively reach and maintain adequate anticoagulation. Several researchers have developed pharmacogenetic-guided maintenance dose algorithms that incorporate genetics and individual patient characteristics. However, there is limited information available concerning dosing during warfarin initiation. This is considered the most clinically challenging therapeutic phase. In such, the risk of recurrent thromboembolism and hemorrhage are elevated. The objective of this retrospective study is to predict the individual initial doses for Puerto Rican patients (n=175) commencing anticoagulation therapy at Veterans Affairs Caribbean Healthcare System (VACHS) using pharmacogenetic/pharmacokinetic-driven model. A pharmacogenetic driven model (R2=0.4809) was developed in Puerto Rican patients and combined with pharmacokinetic formulas that enabled us to predict the individual initial doses for patients (n=121) commencing anticoagulation therapy. WinNonlin® pharmacokinetic-pharmacodynamic simulations were carried out to determine the predictability of this model. This model demonstrated promising results with few (n=10) simulations outside of their respective therapy range. A customized pharmacogenetic-based warfarin maintenance dose algorithm (R2=0.7659) was developed in a derivation cohort of 131 patients. The predictability of this developed pharmacogenetic algorithm was compared with the International Warfarin Pharmacogenomics Consortium (IWPC) algorithm and it demonstrated superior predictability within our study population. PMID:25285240
Alboni, Paolo; Stucci, Nicola; Cojocaru, Elena; Ungar, Andrea
At present, the efficacy and safety of anticoagulants, warfarin, or new oral anticoagulants in frail patients remain unknown, as these patients have largely been excluded from both randomized trials and "real-world" studies; as a result, the guidelines do not provide guidance for the management of this population. Frail patients with atrial fibrillation (AF) are significantly less likely to receive oral anticoagulants compared to their nonfrail counterparts; is that an expression of reasonable prudence or malpractice? In this regard, some aspects of physical frailty should be considered: (i) increased vulnerability to stressors, including pharmacological agents with potential severe adverse effects; (ii) frail elderly patients are at high risk of falls and, therefore, of severe traumatic hemorrhages on oral anticoagulation; (iii) frail patients are more likely to have complications during intercurrent affections, potentially responsible for hemorrhages. Prospective "real-world" studies including frail AF patients are necessary. Waiting for more evidence, the doubt whether to prescribe or not an oral anticoagulant to frail AF patients remains legitimate.
Rediguieri, Camila F; Porta, Valentina; G Nunes, Diana S; Nunes, Taina M; Junginger, Hans E; Kopp, Sabine; Midha, Kamal K; Shah, Vinod P; Stavchansky, Salomon; Dressman, Jennifer B; Barends, Dirk M
Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing metronidazole are reviewed. Metronidazole can be assigned to Biopharmaceutics Classification System Class I. Most BE studies that were identified reported the investigated formulations to be bioequivalent, indicating the risk of bioinequivalence to be low. Formulations showing differences in bioavailability showed dissimilarities in in vitro dissolution profiles. Furthermore, metronidazole has a wide therapeutic index. It is concluded that a biowaiver for solid IR formulations is justified, provided: (a) the test product and its comparator are both rapidly dissolving; (b) meet similarity of the dissolution profiles at pH 1.2, 4.5, and 6.8; (c) the test product contains only excipients present in IR drug products approved in International Conference on Harmonisation (ICH) or associated countries in the same dosage form; and (d) if the test product contains sorbitol, sodium laurilsulfate, or propylene glycol, the test product needs to be qualitatively and quantitatively identical to its comparator with respect to these excipients [corrected]..
Firriolo, F John; Hupp, Wendy S
Warfarin has been the primary anticoagulant drug used in the USA for more than 50 years. However, 2 novel types of oral anticoagulants have recently been approved for use in the USA. These are direct thrombin inhibitors (e.g., dabigatran etexilate) and factor Xa inhibitors (e.g., rivaroxaban). Dental health care providers may soon encounter patients who are being prescribed these medications. This article describes the pharmacologic properties and medical uses of these new oral anticoagulants. Also discussed are implications for the management of dental patients being treated with these new oral anticoagulants, including potential interactions with drugs commonly used or prescribed in the course of dental treatment.
Potthast, H; Dressman, J B; Junginger, H E; Midha, K K; Oeser, H; Shah, V P; Vogelpoel, H; Barends, D M
Literature data are reviewed on the properties of ibuprofen related to the biopharmaceutics classification system (BCS). Ibuprofen was assessed to be a BCS class II drug. Differences in composition and/or manufacturing procedures were reported to have an effect on the rate, but not the extent of absorption; such differences are likely to be detectable by comparative in vitro dissolution tests. Also in view of its therapeutic use, its wide therapeutic index and uncomplicated pharmacokinetic properties, a biowaiver for immediate release (IR) ibuprofen solid oral drug products is scientifically justified, provided that the test product contains only those excipients reported in this paper in their usual amounts, the dosage form is rapidly dissolving (85% in 30 min or less) in buffer pH 6.8 and the test product also exhibits similar dissolution profiles to the reference product in buffer pH 1.2, 4.5, and 6.8.
Jantratid, E; Prakongpan, S; Dressman, J B; Amidon, G L; Junginger, H E; Midha, K K; Barends, D M
Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing cimetidine are reviewed. According to the current Biopharmaceutics Classification System (BCS), cimetidine would be assigned to Class III. Cimetidine's therapeutic use and therapeutic index, its pharmacokinetic properties, data related to the possibility of excipient interactions, and reported BE/bioavailability (BA) problems were also taken into consideration. On the basis of the overall evidence, a biowaiver can be recommended for cimetidine IR products, provided that the test product contains only those excipients reported in this paper in their usual amounts, and that the test and the comparator drug products both are "rapidly dissolving" as per BCS.
Fonseca, Roberto J C; Sucupira, Isabela D; Oliveira, Stephan Nicollas M C G; Santos, Gustavo R C; Mourão, Paulo A S
Fucosylated chondroitin sulfate (FucCS) is a potent anticoagulant polysaccharide extracted from sea cucumber. Its anticoagulant activity is attributed to the presence of unique branches of sulfated fucose. Although this glycosaminoglycan exerts an antithrombotic effect following oral administration, high doses are necessary to achieve the maximum effect. The diminished activity of FucCS following oral administration is likely due to its degradation in the gastrointestinal tract and its limited ability to cross the intestinal cell membranes. The latter aspect is particularly difficult to overcome. However, gastro-resistant tablet formulation may help limit the degradation of FucCS in the gastrointestinal tract. In the present work, we found that the oral administration of FucCS as gastro-resistant tablets produces a more potent and prolonged anticoagulant effect compared with its administration as an aqueous solution, with no significant changes in the bleeding tendency or arterial blood pressure. Experiments using animal models of arterial thrombosis initiated by endothelial injury demonstrated that FucCS delivered as gastro-protective tablets produced a potent antithrombotic effect, whereas its aqueous solution was ineffective. However, there was no significant difference between the effects of FucCS delivered as gastro-resistant tablets or as aqueous solution in a venous thrombosis model, likely due to the high dose of thromboplastin used. New oral anticoagulants tested in these experimental models for comparison showed significantly increased bleeding tendencies. Our study provides a framework for developing effective oral anticoagulants based on sulfated polysaccharides from marine organisms. The present results suggest that FucCS is a promising oral anticoagulant.
Arihiro, Shoji; Todo, Kenichi; Yamagami, Hiroshi; Kimura, Kazumi; Furui, Eisuke; Terasaki, Tadashi; Shiokawa, Yoshiaki; Kamiyama, Kenji; Takizawa, Shunya; Okuda, Satoshi; Okada, Yasushi; Kameda, Tomoaki; Nagakane, Yoshinari; Hasegawa, Yasuhiro; Mochizuki, Hiroshi; Ito, Yasuhiro; Nakashima, Takahiro; Takamatsu, Kazuhiro; Nishiyama, Kazutoshi; Kario, Kazuomi; Sato, Shoichiro; Koga, Masatoshi; Nagatsuka, K; Minematsu, K; Nakagawara, J; Akiyama, H; Shibazaki, K; Maeda, K; Shibuya, S; Yoshimura, S; Endo, K; Miyagi, T; Osaki, M; Kobayashi, J; Okata, T; Tanaka, E; Sakamoto, Y; Takizawa, H; Takasugi, J; Tokunaga, K; Homma, K; Kinoshita, N; Matsuki, T; Higashida, K; Shiozawa, M; Kanai, H; Uehara, S
Background Large clinical trials are lack of data on non‐vitamin K antagonist oral anticoagulants for acute stroke patients. Aim To evaluate the choice of oral anticoagulants at acute hospital discharge in stroke patients with nonvalvular atrial fibrillation and clarify the underlying characteristics potentially affecting that choice using the multicenter Stroke Acute Management with Urgent Risk‐factor Assessment and Improvement‐NVAF registry (ClinicalTrials.gov NCT01581502). Method The study included 1192 acute ischemic stroke/transient ischemic attack patients with nonvalvular atrial fibrillation (527 women, 77·7 ± 9·9 years old) between September 2011 and March 2014, during which three nonvitamin K antagonist oral anticoagulant oral anticoagulants were approved for clinical use. Oral anticoagulant choice at hospital discharge (median 23‐day stay) was assessed. Results Warfarin was chosen for 650 patients, dabigatran for 203, rivaroxaban for 238, and apixaban for 25. Over the three 10‐month observation periods, patients taking warfarin gradually decreased to 46·5% and those taking nonvitamin K antagonist oral anticoagulants increased to 48·0%. As compared with warfarin users, patients taking nonvitamin K antagonist oral anticoagulants included more men, were younger, more frequently had small infarcts, and had lower scores for poststroke CHADS 2, CHA 2 DS 2‐VASc, and HAS‐BLED, admission National Institutes of Health stroke scale, and discharge modified Rankin Scale. Nonvitamin K antagonist oral anticoagulants were started at a median of four‐days after stroke onset without early intracranial hemorrhage. Patients starting nonvitamin K antagonist oral anticoagulants earlier had smaller infarcts and lower scores for the admission National Institutes of Health stroke scale and the discharge modified Rankin Scale than those starting later. Choice of nonvitamin K antagonist oral anticoagulants was independently associated with 20‐day or
Strauch, S; Jantratid, E; Dressman, J B; Junginger, H E; Kopp, S; Midha, K K; Shah, V P; Stavchansky, S; Barends, D M
Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing lamivudine as the only active pharmaceutical ingredient were reviewed. The solubility and permeability data of lamivudine as well as its therapeutic index, its pharmacokinetic properties, data indicating excipient interactions, and reported BE/bioavailability (BA) studies were taken into consideration. Lamivudine is highly soluble, but its permeability characteristics are not well-defined. Reported BA values in adults ranged from 82% to 88%. Therefore, lamivudine is assigned to the biopharmaceutics classification system (BCS) class III, noting that its permeability characteristics are near the border of BCS class I. Lamivudine is not a narrow therapeutic index drug. Provided that (a) the test product contains only excipients present in lamivudine IR solid oral drug products approved in the International Conference on Harmonization or associated countries in usual amounts and (b) the test product as well as the comparator product fulfills the BCS dissolution criteria for very rapidly dissolving; a biowaiver can be recommended for new lamivudine multisource IR products and major post-approval changes of marketed drug products.
Park, J W; Jeon, O C; Kim, S K; Al-Hilal, T A; Lim, K-M; Moon, H T; Kim, C Y; Byun, Y
This study was designed to develop a solid oral dosage form of deoxycholic acid (DOCA)-conjugated low-molecular-weight heparin (LMWH) and to evaluate its oral absorption, distribution, and metabolic stability for the prospect of providing an orally bioavailable LMWH. The LMWH derivative (LHD) was synthesised and then formulated with solubilisers and other pharmaceutical excipients to form a solid tablet. Its absorption and distribution after oral administration were evaluated in mice, rats, and monkeys. The in vitro metabolic stability of LHD was examined by liver microsome assays. More than 80% of LHD was released from the tablet within 60 minutes, guaranteeing rapid tablet disintegration after oral administration. Oral bioavailability of LHD in mice, rats and monkeys were 16.1 ± 3.0, 15.6 ± 6.1, and 15.8 ± 2.5%, respectively. After the oral administration of 131I-tyramine-LHD, most of the absorbed drug remained in the blood circulation and was eliminated mainly through the kidneys. LHD was hardly metabolised by the liver microsomes and showed a stable metabolic pattern similar to that of LMWH. In a rat thrombosis model, 10 mg/kg of orally administered LHD reduced thrombus formation by 60.8%, which was comparable to the anti-thrombotic effect of the subcutaneously injected LMWH (100 IU/kg). Solid tablets of LHD exhibited high oral absorption and statistically significant therapeutic effects in preventing venous thromboembolism. Accordingly, LHD tablets are expected to satisfy the unmet medical need for an oral heparin-based anticoagulant as an alternative to injectable heparin and oral warfarin.
Atrial fibrillation (AF) is the most common cardiac arrhythmia worldwide. Strokes that occur as a complication of AF are usually more severe and associated with a higher disability or morbidity and mortality rate compared with non-AF-related strokes. The risk of stroke in AF is dependent on several risk factors; AF itself acts as an independent risk factor for stroke. The combination of effective anticoagulation therapy, risk stratification (based on stroke risk scores, such as CHADS2 and CHA2DS2-VASc), and recommendations provided by guidelines is essential for decreasing the risk of stroke in patients with AF. Although effective in preventing the occurrence of stroke, vitamin K antagonists (VKAs; eg, warfarin) are associated with several limitations. Therefore, direct oral anticoagulants, such as apixaban, dabigatran etexilate, edoxaban, and rivaroxaban, have emerged as an alternative to the VKAs for stroke prevention in patients with nonvalvular AF. Compared with the VKAs, these agents have more favorable pharmacological characteristics and, unlike the VKAs, they are given at fixed doses without the need for routine coagulation monitoring. It remains important that physicians use these direct oral anticoagulants responsibly to ensure optimal safety and effectiveness. This article provides an overview of the existing data on the direct oral anticoagulants, focusing on management protocols for aiding physicians to optimize anticoagulant therapy in patients with nonvalvular AF, particularly in special patient populations (eg, those with renal impairment) and other specific clinical situations. PMID:26089678
Atrial fibrillation (AF) is the most common cardiac arrhythmia worldwide. Strokes that occur as a complication of AF are usually more severe and associated with a higher disability or morbidity and mortality rate compared with non-AF-related strokes. The risk of stroke in AF is dependent on several risk factors; AF itself acts as an independent risk factor for stroke. The combination of effective anticoagulation therapy, risk stratification (based on stroke risk scores, such as CHADS2 and CHA2DS2-VASc), and recommendations provided by guidelines is essential for decreasing the risk of stroke in patients with AF. Although effective in preventing the occurrence of stroke, vitamin K antagonists (VKAs; e.g., warfarin) are associated with several limitations. Therefore, direct oral anticoagulants, such as apixaban, dabigatran etexilate, edoxaban, and rivaroxaban, have emerged as an alternative to the VKAs for stroke prevention in patients with nonvalvular AF. Compared with the VKAs, these agents have more favorable pharmacological characteristics and, unlike the VKAs, they are given at fixed doses without the need for routine coagulation monitoring. It remains important that physicians use these direct oral anticoagulants responsibly to ensure optimal safety and effectiveness. This article provides an overview of the existing data on the direct oral anticoagulants, focusing on management protocols for aiding physicians to optimize anticoagulant therapy in patients with nonvalvular AF, particularly in special patient populations (e.g., those with renal impairment) and other specific clinical situations.
The dynamic evolution of therapeutic options including the use of vitamin K antagonists (VKA), non-vitamin K oral anticoagulants (NOAC), more potent antiplatelet drugs as well as new generation drug-eluting stents could lead to the view that the current recommendations on the management of patients with percutaneous coronary intervention (PCI) requiring oral anticoagulation do not keep up with the results of several clinical studies published within the last 5 years. In the present overview, we summarize the recent advances in antithrombotic management used in atrial fibrillation patients undergoing PCI for stable coronary artery disease or acute coronary syndrome (ACS). The safety and efficacy of prasugrel and ticagrelor taken with oral anticoagulants also remain to be established in randomized trials; therefore the P2Y12 inhibitor clopidogrel on top of aspirin or without is now recommended to be used together with a VKA or NOAC. It is still unclear which dose of a NOAC in combination with antiplatelet agents and different stents should be used in this clinical setting and whether indeed NOAC are safer compared with VKA in such cardiovascular patients. Moreover, we discuss the use of anticoagulation in addition to antiplatelet therapy for secondary prevention in patients with ACS. To minimize bleeding risk in anticoagulated patients following PCI or ACS, the right agent should be prescribed to the right patient at the right dose and supported by regular clinical evaluation and laboratory testing, especially assessment of renal function when a NOAC is used. PMID:27980542
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Halperin, Jonathan L; Dorian, Paul
Patients with non-valvular atrial fibrillation (AF) face an increased risk of stroke compared with those in normal sinus rhythm. The vitamin K antagonist warfarin, available for over half a century, is highly effective in reducing the risk of stroke in patients with AF, but it is a difficult drug to use properly. As a result, it is challenging to keep the anticoagulant effect of warfarin in the desired range. Newer oral anticoagulants (NOACs) that directly inhibit Factor IIa (thrombin) or Factor Xa provide reliable anticoagulation when administer in fixed oral doses without routine coagulation monitoring. This manuscript will review in detail the pivotal trials of these NOACs that led to their approval as well as comment on the factors that should influence their selection. PMID:24821657
Albert, Nancy M
Atrial fibrillation (AF), a common arrhythmia, increases the risk of ischemic stroke. Stroke and bleeding scores for patients with AF can help to stratify risk and determine the need for antithrombotic therapy, for which warfarin has been the gold standard. Although highly effective, warfarin has several limitations that can lead to its underuse. Data from randomized, Phase III clinical trials of the novel oral anticoagulants, dabigatran, a direct thrombin inhibitor, and rivaroxaban and apixaban, both factor Xa inhibitors, indicate these drugs are at least noninferior to warfarin for the prevention of stroke and systemic embolism. They are easier to administer, and have an equivalent or lower risk of bleeding versus warfarin. A better understanding of the risks and benefits of the novel oral anticoagulants, and their use in clinical practice, will prepare clinicians to anticipate and address educational and clinical needs of AF patients and their families, and promote evidence-based prescription of appropriate and safe anticoagulation therapy.
Hidalgo, F; Gómez-Luque, A; Ferrandis, R; Llau, J V; de Andrés, J; Gomar, C; Sierra, P; Castillo, J; Torres, L M
There is an almost unanimous consensus on the management of the direct new oral anticoagulants, dabigatran, rivaroxaban, and apixaban in elective surgery. However, this general consensus does not exist in relation with the direct new oral anticoagulants use in emergency surgery, especially in the bleeding patient. For this reason, a literature review was performed using the MEDLINE-PubMed. An analysis was made of the journal articles, reviews, systematic reviews, and practices guidelines published between 2000 and 2014 using the terms "monitoring" and "reversal". From this review, it was shown that the routine tests of blood coagulation, such as the prothrombin time and activated partial thromboplastin time, have a limited efficacy in the perioperative control of blood coagulation in these patients. There is currently no antidote to reverse the effects of these drugs, although the possibility of using concentrated prothrombin complex and recombinant activated factor vii has been suggested for the urgent reversal of the anticoagulant effect.
Okata, Takuya; Toyoda, Kazunori; Okamoto, Akira; Miyata, Toshiyuki; Nagatsuka, Kazuyuki; Minematsu, Kazuo
Objectives In Japan, low-dose rivaroxaban [15 mg QD/10 mg QD for creatinine clearance of 30–49 mL/min] was approved for clinical use in NVAF patients partly because of its unique pharmacokinetics in Japanese subjects. The aim of the study was to determine the anticoagulation intensity of rivaroxaban and its determinant factors in Japanese stroke patients. Methods Consecutive stroke patients with NVAF admitted between July 2012 and December 2013 were studied. Prothrombin time (PT), activated partial thromboplastin time (aPTT), and estimated plasma concentration of rivaroxaban (Criv) based on an anti-factor Xa chromogenic assay were measured just before and 4 and 9 h after administration at the steady state level of rivaroxaban. Determinant factors for Criv were explored using a linear mixed-model approach. Results Of 110 patients (37 women, 75±9 years old), 59 took 15 mg QD of rivaroxaban and 51 took 10 mg QD. Criv at 4 h was 186 ng/mL for patients taking 15 mg QD and 147 ng/mL for those taking 10 mg QD. Both PT and aPTT were positively correlated with Criv. Criv was 72% lower at 4 h in 15 patients receiving crushed tablets than in the other patients, and tablet crushing was significantly associated with lower Criv (adjusted estimate −0.43, 95% CI −0.60 to −0.26) after multivariate-adjustment. Conclusion The anticoagulation effects of rivaroxaban in the acute stroke setting for Japanese NVAF patients were relatively low as compared with those in the ROCKET-AF and J-ROCKET AF trials. Tablet crushing, common in dysphagic patients, decreased Criv. PMID:25479967
Hellfritzsch, Maja; Husted, Steen Elkjaer; Grove, Erik Lerkevang; Rasmussen, Lotte; Poulsen, Birgitte Klindt; Johnsen, Søren Paaske; Hallas, Jesper; Pottegård, Anton
Patients with atrial fibrillation discontinuing anticoagulant therapy are left unprotected against ischaemic stroke. Further, switching between oral anticoagulants may be associated with a transiently increased risk of bleeding or thromboembolism. However, there is a paucity of real-life data on pattern of switching and discontinuation of oral anticoagulants. To address this, we conducted a nationwide drug utilization study including all registered Danish atrial fibrillation patients initiating a non-VKA oral anticoagulant (NOAC) between August 2011 and February 2016. We assessed changes in anticoagulant treatment, including switching between oral anticoagulants and discontinuation of NOACs, and explored patient characteristics predicting these changes. We identified 50,632 patients with atrial fibrillation initiating NOAC therapy within the study period. The majority initiated dabigatran (49.9%) and one-third had previously used VKA. Within 1 year, 10.1% switched to VKA, 4.8% switched to another NOAC and 14.4% discontinued treatment. The frequencies of switching to VKA and discontinuation were highest among NOAC users of young age (<55 years) and with low CHA2 DS2 -VASc score (=0). However, the majority of patients (87.3%) stopping NOAC treatment had a CHA2 DS2 -VASc score ≥1. We conclude that switching from VKA to NOAC, and to a lesser extent from NOAC to VKA, is common, as is early treatment discontinuation. The majority of treatment changes are observed in patients at increased risk of stroke. More research is warranted on the risks of bleeding and thromboembolism associated with switching and discontinuation of NOACs as well as the underlying reasons why these treatment changes occur.
Zeus, Tobias; Kelm, Malte; Bode, Christoph
Thrombo-embolic prophylaxis is a key element within the therapy of atrial fibrillation/atrial flutter. Besides new oral anticoagulants the concept of left atrial appendage occlusion has approved to be a good alternative option, especially in patients with increased risk of bleeding.
Perry, D J; Noakes, T J C; Helliwell, P S
The objective of these guidelines is to provide healthcare professionals, including primary care dental practitioners, with clear guidance on the management of patients on oral anticoagulants requiring dental surgery. The guidance may not be appropriate in all cases and individual patient circumstances may dictate an alternative approach.
Contractor, Tahmeed; Levin, Vadim; Martinez, Matthew W; Marchlinski, Francis E
Atrial fibrillation (AF) is an important cause of ischemic stroke and is the underlying cause of > 20% of all strokes, with increasing age being a risk factor. Until recently, warfarin was the only available oral anticoagulant used to decrease this risk in patients with AF. However, there are several disadvantages of warfarin use, such as the requirement for monitoring the international normalized ratio, its wide range of drug-food interactions, and its narrow therapeutic index. Thus, there has been a strong impetus for the development of newer oral anticoagulants with predictable pharmacokinetics that obviate the need for monitoring the international normalized ratio. The US Food and Drug Administration has approved a direct thrombin inhibitor (dabigatran) and 2 factor Xa inhibitors (rivaroxaban and apixaban) for stroke prevention in patients with nonvalvular AF. There are several other new oral anticoagulant agents on the horizon, including the factor Xa inhibitor edoxaban. This review article discusses the pharmacological properties, clinical trial data, and practical issues associated with the use of these novel oral anticoagulants.
This review discusses the basic pharmacology of new oral anticoagulants that are used for prevention of thromboembolism in patients with atrial fibrillation. It presents available evidence, and provides recommendations for the management of patients requiring invasive procedures in dental practice. PMID:26835072
Goodarzi, Navid; Barazesh Morgani, Ahmadreza; Abrahamsson, Bertil; Cristofoletti, Rodrigo; Groot, D W; Langguth, Peter; Mehta, Mehul U; Polli, James E; Shah, Vinod P; Dressman, Jennifer B
Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release solid oral dosage forms containing ribavirin are reviewed. Ribavirin is highly soluble, but its permeability characteristics are not well defined. Therefore according to the Biopharmaceutical Classification System, and taking a "worst case" approach, ribavirin should be assigned to class III. As ribavirin is transported across the brush border membrane of the human jejunum by hCNT2, it shows saturable uptake in the intestine. However, no common excipients have been shown to compete for ribavirin absorption, nor have problems with BE of immediate release ribavirin formulations containing different excipients and produced by different manufacturing methods been reported in the open literature. So the risk of bioinequivalence caused by these factors appears to be low. Ribavirin is considered a narrow therapeutic index drug, as judged by comparing the minimum effective concentration and minimum toxic concentrations in blood. Although ribavirin would not be eligible for approval via a Biopharmaceutical Classification System-based biowaiver procedure according to today's guidances due to its narrow therapeutic index, the risks of biowaiving should be weighed against the considerable risks associated with studying BE of ribavirin products in healthy subjects.
Madan, Shivanshu; Shah, Shenil; Partovi, Sasan
The increasing availability of novel oral anticoagulants (NOAC) for the prevention of stroke and systemic embolism in patients with nonvalvular atrial fibrillation (AF) offers alternatives for patients currently prescribed warfarin. This article provides a brief overview on the mechanism and clinical use of these drugs as well as a review of the pivotal clinical trials providing the basis for each agent’s safety and efficacy. While these agents are currently Food and Drug Administration (FDA) approved for anticoagulation of patients with nonvalvular AF, additional studies continually emerge offering further insight into the application of these agents in other areas. PMID:25276617
Ten Cate, Hugo
New oral anticoagulants (NOACs) have been introduced to improve anticoagulant therapy worldwide, but safe implementation may require additional measures. First, optimization of dose adjustment based on therapeutic levels of the drug may be more appropriate than fixed dose therapy. The development and implementation in quantitative laboratory assays will enable further dose optimization. Second, non-adherence to medication is a potential threat to the safe use of NOACs. Since cardiovascular medication may not be optimally used in about 50% of patients, procedures to improve adherence are imperative, also for NOAC therapy and in particular in elderly patients.
Potpara, Tatjana S; Polovina, Marija M; Licina, Marina M; Stojanovic, Radan M; Prostran, Milica S; Lip, Gregory Y H
Stroke prevention in atrial fibrillation (AF) has been challenging over decades, mostly due to a number of difficulties associated with oral vitamin K antagonists (VKAs), which have been the most effective stroke prevention treatment for a long time. The oral direct thrombin inhibitors (e.g., dabigatran) and oral direct inhibitors of factor Xa (e.g., rivaroxaban, apixaban) have emerged recently as an alternative to VKAs for stroke prevention in AF. These drugs act rapidly, and have a predictable and stable dose-related anticoagulant effect with a few clinically relevant drug-drug interactions. The novel oral anticoagulants are used in fixed doses with no need for regular laboratory monitoring of anticoagulation intensity. However, each of these drugs has distinct pharmacological properties that could influence optimal use in clinical practice. The following phase 3 randomized trials with novel oral anticoagulants versus warfarin for stroke prevention in AF have been completed: the Randomized Evaluation of Long-term Anticoagulant therapy (RE-LY) trial with dabigatran, the Rivaroxaban Once daily oral direct Factor Xa inhibition Compared with vitamin K antagonism for prevention of stroke and Embolism Trial in Atrial Fibrillation (ROCKET-AF) trial with rivaroxaban, and the Apixaban for Reduction of Stroke and Other Thromboembolism Events in Atrial Fibrillation (ARISTOTLE) trial with apixaban. Moreover, the Apixaban Versus Acetylsalicylic Acid to prevent Strokes (AVERROES) trial included patients with AF who have failed or were unsuitable for warfarin, and compared apixaban versus aspirin for stroke prevention in AF. Overall, apixaban has two large trials for stroke prevention in AF showing benefits not only over warfarin, but also over aspirin among those patients who have failed or refused warfarin. In the ARISTOTLE trial, apixaban was superior to warfarin in the reduction of stroke or systemic embolism, major bleeding, intracranial hemorrhage, and all-cause mortality
Hale, Zachary D; Kong, Xiowen; Haymart, Brian; Gu, Xiaokui; Kline-Rogers, Eva; Almany, Steve; Kozlowski, Jay; Krol, Gregory D; Kaatz, Scott; Froehlich, James B; Barnes, Geoffrey D
Direct oral anticoagulant (DOAC) agents offer several lifestyle and therapeutic advantages for patients relative to warfarin in the treatment of atrial fibrillation (AF). These alternative agents are increasingly used in the treatment of AF, however the adoption practices, patient profiles, and reasons for switching to a DOAC from warfarin have not been well studied. Through the Michigan Anticoagulation Quality Improvement Initiative, abstracted data from 3873 AF patients, enrolled between 2010 and 2015, were collected on demographics and comorbid conditions, stroke and bleeding risk scores, and reasons for anticoagulant switching. Over the study period, patients who switched from warfarin to a DOAC had similar baseline characteristics, risk scores, and insurance status but differed in baseline CrCl. The most common reasons for switching were patient related ease of use concerns (37.5%) as opposed to clinical reasons (16.5% of patients). Only 13% of patients that switched to a DOAC switched back to warfarin by the end of the study period.
Chang, Jeremy B; Quinnies, Kayla M; Realubit, Ronald; Karan, Charles; Rand, Jacob H; Tatonetti, Nicholas P
A central challenge in designing and administering effective anticoagulants is achieving the proper therapeutic window and dosage for each patient. The Hill coefficient, nH, which measures the steepness of a dose-response relationship, may be a useful gauge of this therapeutic window. We sought to measure the Hill coefficient of available anticoagulants to gain insight into their therapeutic windows. We used a simple fluorometric in vitro assay to determine clotting activity in platelet poor plasma after exposure to various concentrations of anticoagulants. The Hill coefficient for argatroban was the lowest, at 1.7 ± 0.2 (95% confidence interval, CI), and the Hill coefficient for fondaparinux was the highest, at 4.5 ± 1.3 (95% CI). Thus, doubling the dose of fondaparinux from its IC50 would decrease coagulation activity by nearly a half, whereas doubling the dose of argatroban from its IC50 would decrease coagulation activity by merely one quarter. These results show a significant variation among the Hill coefficients, suggesting a similar variation in therapeutic windows among anticoagulants in our assay.
Grundy, J S; Kherani, R; Foster, R T
Nifedipine (NIF), a 1,4-dihydropyridine calcium channel antagonist, undergoes photodegradation to dehydronifedipine (DNIF) upon exposure to ultraviolet (UV) light and to the nitroso analogue of dehydronifedipine (NDNIF) when exposed to sunlight. NIF photodegradation products do not contribute to clinical activity, thus the content of NIF must remain uniform between equipotent formulations. Large differences in light stability between bioequivalent NIF products could potentially result in the therapeutic failure of unstable preparations. Consequently, if large photostability differences do exist between NIF preparations, product substitution may not be warranted. The light stability of 10 intact immediate- or controlled-release oral NIF formulations, obtained from several European and North American manufacturers, was studied using direct continuous artificial sunlight exposure extending over a 12-week period. The content of both NIF and NDNIF for each product was measured to determine the extent of photodecomposition using a specific and sensitive reversed-phase high pressure liquid chromatographic (HPLC) method. In addition, NIF photodegradation was measured using both pure NIF powder and methanolic NIF solution to determine the effectiveness of the artificial sunlight source used in this study. After 12 weeks of artificial sunlight exposure, less than 3% of NDNIF (w/w initial NIF content) was present in each of the 10 tested dosage forms. Photodegradation was greater than 10% (w/w initial NIF content) in approximately 5-10 min (mean t1/2 = 31 min), and in approximately 24 h (mean t1/2 = 7.7 days) of artificial sunlight exposure for methanolic NIF solution and pure NIF powder samples, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)
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Zhang, Jing-Tao; Chen, Ke-Ping; Zhang, Shu
Abstract The purpose of this study was to perform a meta-analysis comparing the effectiveness and safety of anticoagulation to antiplatelet therapy for the prevention of thromboembolic events in patients with atrial fibrillation (AF). MEDLINE, Cochrane, EMBASE, and Google Scholar databases were searched for studies published through May 31, 2014. Randomized controlled trials comparing anticoagulants (warfarin) and antiplatelet therapy in patients with AF were included. The primary outcomes were the rates of stroke and systemic embolism. Secondary outcomes included the rates of hemorrhage/major bleeding and death. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. Nine reports of 8 trials that enrolled 4363 patients (2169 patients received anticoagulation and 2194 antiplatelet therapy) were included. All of the studies compared adjusted-dose warfarin or with aspirin, and the majority of the patients were >70 years of age. Anticoagulants were titrated to an international normalized ratio (INR) of 2.0 to 4.5, and aspirin was administered at a dosage of 75 to 325 mg/d. Death occurred in 206 participants treated with an anticoagulant and 229 participants treated with antiplatelet therapy. There was no significant difference in the overall stroke rate between the groups (OR = 0.667, 95% CI 0.426–1.045, P = 0.08); however, patients with nonrheumatic AF (NRAF) treated with an anticoagulant had a lower risk of stroke (OR = 0.557, 95% CI 0.411–0.753, P < 0.001). Anticoagulants were associated with a lower risk of embolism (OR = 0.616, 95% CI = 0.392–0.966, P = 0.04), and this finding persisted in patients with NRAF (OR = 0.581, 95% CI 0.359–0.941, P = 0.03). No significant difference in the rate of hemorrhage/major bleeding was noted (OR = 1.497, 95% CI 0.730–3.070, P = 0.27), and this finding persisted on subgroup analysis. Anticoagulants appear to be more effective than aspirin in preventing
Pereira, Claudio Maranhão; Gasparetto, Patrícia Freire; Carneiro, Danilo Santos; Corrêa, Maria Elvira P.; Souza, Cármino Antônio
Introduction. Dental treatment performed in patients receiving continuous oral anticoagulant drug therapy is becoming increasingly common in dental offices. For these patients it is imperative to carry out careful anamnesis, as well as a multiprofessional clinical evaluation with regard to the risk and control of hemorrhagic or thromboembolic episodes. Objectives and Material and Methods. The aim is to evaluate postextraction hemorrhagic or thromboembolic episodes in patients who have been on anticoagulant medications for an uninterrupted period of 48 months. Results. Among the 108 patients evaluated, 215 extractions were performed in which there was only one case of postoperative bleeding. Warfarin was used by 98 patients; Warfarin associated with salicylic acetic acid by 9 patients and salicylic acetic acid in only 1 patient. As regards the serologic tests performed, International Normalized Ratio (INR) ranged from 0.8 to 4.9, with a mean of 3.15. Conclusion. Extractions in patients on oral anticoagulants must be performed in the least traumatic manner possible. It is not necessary to stop anticoagulant therapy to perform extractions. Local hemostasis techniques, such as obliterative sutures alone are sufficient to prevent hemorrhagic complications. PMID:21991458
Habert, Jeffrey Steven
Many primary care physicians are wary about using direct oral anticoagulants (DOACs) in patients with nonvalvular atrial fibrillation (AF). Factors such as comorbidities, concomitant medications, and alcohol misuse increase concerns over bleeding risk, especially in elderly and frail patients with AF. This article discusses strategies to minimize the risk of major bleeding events in patients with AF who may benefit from oral anticoagulant therapy for stroke prevention. The potential benefits of the DOACs compared with vitamin K antagonists, in terms of a lower risk of intracranial hemorrhage, are discussed, together with the identification of reversible risk factors for bleeding and correct dose selection of the DOACs based on a patient’s characteristics and concomitant medications. Current bleeding management strategies, including the new reversal agents for the DOACs and the prevention of bleeding during preoperative anticoagulation treatment, in addition to health care resource use associated with anticoagulation treatment and bleeding, are also discussed. Implementing a structured approach at an individual patient level will minimize the overall risk of bleeding and should increase physician confidence in using the DOACs for stroke prevention in their patients with nonvalvular AF. PMID:27785089
Reisenwitz, T H; Wimbish, G J
The capsule dosage form in nonprescription pharmaceuticals persists as being one of the most vulnerable to product tampering. This study examines consumer preference toward three solid oral dosage forms (capsules, caplets, and tablets) in nonprescription products. Thirteen independent variables representing dosage form attributes are measured on semantic differential scales. The data are analyzed using analysis of variance (ANOVA) and factor analysis. Implications for the pharmaceutical marketer are noted. Future directions for research are also outlined.
Sawicka-Powierza, Jolanta; Rogowska-Szadkowska, Dorota; Ołtarzewska, Alicja Małgorzata; Chlabicz, Sławomir
Oral anticoagulants (OAC) are commonly used as a life-long therapy in prevention of systemic embolism in patients with atrial fibrillation, valvular heart disease and prosthetic hart valves and in the primary and secondary prevention of venous thromboembolism. They are also used for the prevention of thromboembolic events in patients with acute myocardial infarction and with angina pectoris, in patients with biological hart valves and after some types of orthopaedics surgery. The International Normalized Ratio (INR) is used to evaluate the efficacy of anti-coagulant therapy. The risk of thromboembolic and haemorrhagic complications increases when the INR is out of the therapeutic range. The aim of this study was to present information about the factors influencing activity of oral anticoagulants and interactions between oral anticoagulants and drugs or food. The effect of oral anticoagulants is influenced by genetic and environmental factors such as: medicines, food, diseases and pre-existing conditions. A common mutation in the gene coding for the cytochrome P450 (CYP2C9), with one or more combinations of its polymorphisms, is responsible for the reduced warfarin requirements or for the resistance to warfarin. A mutation in the factor IX is responsible for the risk of bleeding during OAC therapy without excessive prolongation of the prothrombin time (PT). Drugs, herbs and multivitamin supplements can alter the absorption, pharmacokinetics or pharmakodynamics of OAC. Nonsteroid anti-inflammatory drugs and paracetamol in combination with OAC seem to be the most dangerous because they are available without prescription and are used without medical consultation. Patients on OAC therapy are sensitive to changing dietary intake of vitamin K, which is supplied from phylloquinones in plants or from vitamin K-containing medicines. The effect of OAC can be influenced by other existing factors like: fever, diarrhoea, alcohol abuse or physical hyperactivity. Some malignancies
Atrial fibrillation (AF) is associated with an increased incidence and severity of strokes. The burden of AF-related stroke is expected to increase in parallel with the aging of the population. Oral anticoagulation with warfarin has been the pharmacologic standard for stroke risk reduction in patients with AF. When used with close attention to dosing and monitoring, warfarin is effective prophylactic therapy against thromboembolic stroke. However, it is underused by physicians, in part because of the known risks of adverse events with warfarin. Consequently, many patients with AF live with an avoidably elevated risk of stroke. New options, ie, oral anticoagulants with novel mechanisms of action, have recently been approved to reduce the risk of stroke in AF, and others are in development. These newer agents may address some of the complexities of warfarin use while providing similar or better efficacy and safety.
Gulba, D C; Broscaru, L
Since first used in 2009, non-vitamin K oral anticoagulants (NOAC) have gained world-wide acceptance. Two groups of NOAC are currently used: the direct thrombin antagonist dabigatran and three direct factor Xa antagonists apixaban, edoxaban, and ricaroxaban. With their increasing use for prevention of thromboembolism, the probability increases that NOAC-pretreated patients are admitted to emergency departments or intensive care units.The clinical challenge in NOAC preanticoagulated patients is to adequately cope with the given anticoagulated status of such patients. Because of their short half-life, many patients will be adequately treated with a "wait and see" approach, and surgeries and interventions are postponed until anticoagulant activities have totally subsided. In the few cases where immediate action is mandated, based on appropriate risk assessments it can be decided either to take the increased hemorrhagic risk of early intervention or to transfuse factor concentrates like PPSB or FEIBA which can safely reverse the anticoagulant activities of the three factor Xa antagonists (and potentially also of dabigatran). Recently a humanized Fab antibody fragment for dabigatran, idarucizumab, has been introduced onto the market, that can immediately reverse the anticoagulant effects of dabigatran. For the reversal of dabigatran, idarucizumab is therefore the drug of choice.In addition, in some specific indications of emergency and intensive care medicine, the primary use of a NOAC can be considered advantageous. Such indications are early cardioversion in patients admitted for new episodes of atrial fibrillation and patients with acute pulmonary embolism. For the widespread use of low-molecular-weight heparins in such indications, however, the decision to use a NOAC for anticoagulant therapy is frequently postponed to the treatment phase when the stabilized patient is already treated on the general ward.
Li, Liang; Zhang, Xin; Gu, Xiangqin; Mao, Shirui
Solid oral modified-release dosage forms provide numerous advantages for drug delivery compared to dosage forms where the drugs are released and absorbed rapidly following ingestion. Natural polymers are of particular interest as drug carriers due to their good safety profile, biocompatibility, biodegradability, and rich sources. This review described the current applications of important natural polymers, such as chitosan, alginate, pectin, guar gum, and xanthan gum, in solid oral modified-release dosage forms. It was shown that natural polymers have been widely used to fabricate solid oral modified-release dosage forms such as matrix tablets, pellets and beads, and especially oral drug delivery systems such as gastroretentive and colon drug delivery systems. Moreover, chemical modifications could overcome the shortcomings associated with the use of natural polymers, and the combination of two or more polymers presented further advantages compared with that of single polymer. In conclusion, natural polymers and modified natural polymers have promising applications in solid oral modified-release dosage forms. However, commercial products based on them are still limited. To accelerate the application of natural polymers in commercial products, in vivo behavior of natural polymers-based solid oral modified-release dosage forms should be deeply investigated, and meanwhile quality of the natural polymers should be controlled strictly, and the influence of formulation and process parameters need to be understood intensively.
Cayla, Guillaume; Leclercq, Florence; Schmutz, Laurent; Cornillet, Luc; Ledermann, Bertrand; Messner, Patrick; Lattuca, Benoit
Venous thromboembolism and atrial fibrillation are two important indications of direct oral anticoagulants. Acute coronary syndrome is another potential indication of prolonged antithrombotic therapy in addition to antiplatelet therapy. Phase 2 and 3 studies were conducted with different molecules at different doses in acute coronary syndrome in addition to dual antiplatelet therapy. Studies have not shown a reduction of ischemic events for dabigatran and apixaban, but an excess of bleeding complications was observed. A reduction of ischemic events and stent thrombosis was observed with low dose of rivaroxaban taken twice a day but with an increased risk of major bleeding complications. This data was used to obtain a European marketing authorization but the positioning of the molecule remains difficult. A new study is currently being conducted to test rivaroxaban in association with a P2Y12 inhibitor without aspirin. Direct oral anticoagulants can also be used after percutaneous coronary intervention in patients requiring long-term oral anticoagulants. Dedicated studies are currently being conducted to confirm the optimal doses and the ideal association of antithrombotic drugs.
López-Lacomba, Daniel; Roa-López, Antonio; González-Jaranay, Maximino; Gómez-Moreno, Gerardo
Background The aim is to evaluate periodontal alteration and biochemical markers associated with bone turnover in chronic oral with dicoumarins anticoagulant treatment patients. Material and Methods 80 patients treated with oral anticoagulants were divided into 2 cohort: Group A (n=36) 6 month to 1 year with anticoagulant treatment and Group B (n=44) > 2 years with anticoagulant treatment. Clinical evaluation included: Clinical attachment level (CAL), plaque index (PI) and gingival index (GI). Analytically biochemical parameters of bone remodeling (calcium and phosphorus), formation (total acid phosphatase, alkaline phosphatase and osteocalcin) and resorption (tartrate-resistant acid phosphatase and beta-crosslaps) were evaluated. Results High values of PI (67-100%) especially in men and in Group B were observed. Men with anticoagulation treatment length showed an increased GI (49.167 vs 78.083) while Group B women showed a decreased GI in comparison with Group A (59.389 vs 42.120). Women presented a greater average CAL than men as well as Group B vs Group A but without statistical significance. All biochemical markers were decreased respect to values of general population. Osteocalcin in GroupB women showed a statistically significant outcome vs GroupA (p=0.004). Acid phosphatase (total and tartrate-resistant) has a slight increase in Group B women versus Group A, and Beta-crosslap showed lower values in Group A men than Group B and slightly lower in Group A women versus Group B, without statistical significance. Conclusions Patients showed a slight to moderate degree of periodontal affectation, especially gingivitis related to bacterial plaque. Periodontal disorders tended to be more severe in Group B. While bone remodeling showed an overall decrease with greater affectation of bone neoformation phenomena, bone destruction tended to recover and normalize in time. Key words:Periodontal disease, dicoumarin, biochemical markers, bone remodeling. PMID:28160591
Ramírez-Martínez-Acitores, Lucía; López-Pintor, Rosa Mª; Casañas-Gil, Elisabeth; Hernández-Vallejo, Gonzalo
Background Dabigatran is a newly commercialized drug that is replacing other anticoagulants in the prevention of venous thromboembolism, stroke and systemic arterial valve embolism. It acts directly on thrombin presenting in a dynamic and predictable way, which does not require monitoring these patients. Therefore, we consider the need to assess whether their use increases the risk of bleeding involved before any dental treatment. Material and Methods We performed a systematic review with a bibliographic search in PubMed/Medline along with the Cochrane Library. We excluded articles dealing with all anticoagulants other than dabigatran, and works about surgical treatments in anatomical locations other than the oral cavity. Results We included a total of 13 papers of which 1 was a randomized clinical trial, 9 narrative literature reviews, 1 case series, 2 clinical cases and 1 expert opinion. Because we did not obtain any properly designed clinical trials, we were unable to conduct a meta-analysis. Conclusions Currently, there is no consensus on the procedure to be followed in patients taking dabigatran. However, all authors agree to treat each case individually in accordance to the risk of embolism, postoperative bleeding and renal function. Also, it is necessary to perform minimally invasive interventions, and take the appropriate local anti-hemolytic measures. Key words:Oral anticoagulants, dabigatran, risk of bleeding, oral surgery, dentistry. PMID:27694780
Pereira-Da-Silva, Tiago; Souto Moura, Teresa; Azevedo, Luísa; Sá Pereira, Margarida; Virella, Daniel; Alves, Marta; Borges, Luís
Introdução e Objetivos: Avaliar a taxa de prescrição de anticoagulantes orais na fibrilhação auricular, os fatores associados à não prescrição, os motivos referidos pelos clínicos para não prescrição de anticoagulantes incluindo os de nova geração e realizar estudo evolutivo a médio prazo. Material e Métodos: Estudo prospetivo sobre casos consecutivos de doentes com fibrilhação auricular com alta hospitalar. Registaram- se os scores CHA2DS2VASc e HASBLED, comorbilidades associadas e a medicação prévia e à data de alta. Na alta hospitalar, o médico assistente indicou em questionário o motivo de não prescrição de anticoagulantes orais e dos novos anticoagulantes orais. Exclusão: contra-indicação absoluta para anticoagulação, CHA2DS2VASc ≤ 1 e doença valvular. Os doentes foram reavaliados um ano após o recrutamento do primeiro doente. Resultados: Identificaram-se 103 candidatos a anticoagulação oral (79,6 ± 8,0 anos; CHA2DS2VASc 5,8 ± 1,4; HASBLED 2,6 ± 1,0; HASBLED ≥ 3 em 55,3%); os anticoagulantes foram prescritos em 34,0%. Fatores associados à não prescrição por ordem decrescente de relevância: uso prévio de antiagregantes, doente acamado e/ou demente, ausência de insuficiência cardíaca e número de fatores de risco hemorrágico. Razões invocadas para não prescrição por ordem decrescente de frequência: risco hemorrágico elevado, pequeno benefício, incapacidade de seguir o esquema terapêutico e dificuldade na monitorização da razão normalizada internacional (INR). Os novos anticoagulantes não foram prescritos e as razões invocadas foram, por ordem decrescente de frequência: informação insuficiente sobre estes fármacos, risco hemorrágico elevado, custo elevado e pequeno benefício. Aos 8,2 ± 2,5 meses de estudo evolutivo 33,3% dos doentes encontravam-se sob anticoagulação sem que os novos anticoagulantes tivessem sido prescritos. Conclusões: Nesta amostra, a taxa de prescrição de
Mega, Jessica L; Simon, Tabassome
Antithrombotic drugs, which include antiplatelet and anticoagulant therapies, prevent and treat many cardiovascular disorders and, as such, are some of the most commonly prescribed drugs worldwide. The first drugs designed to inhibit platelets or coagulation factors, such as the antiplatelet clopidogrel and the anticoagulant warfarin, significantly reduced the risk of thrombotic events at the cost of increased bleeding in patients. However, both clopidogrel and warfarin have some pharmacological limitations including interpatient variability in antithrombotic effects in part due to the metabolism, interactions (eg, drug, environment, and genetic), or targets of the drugs. Increased knowledge of the pharmacology of antithrombotic drugs and the mechanisms underlying thrombosis has led to the development of newer drugs with faster onset of action, fewer interactions, and less interpatient variability in their antithrombotic effects than previous antithrombotic drugs. Treatment options now include the next-generation antiplatelet drugs prasugrel and ticagrelor, and, in terms of anticoagulants, inhibitors that directly target factor IIa (dabigatran) or Xa (rivaroxaban, apixaban, edoxaban) are available. In this Series paper we review the pharmacological properties of these most commonly used oral antithrombotic drugs, and explore the development of antiplatelet and anticoagulant therapies.
Borgman, Mark P; Pendleton, Robert C; McMillin, Gwendolyn A; Reynolds, Kristen K; Vazquez, Sara; Freeman, Andrew; Wilson, Andrew; Valdes, Roland; Linder, Mark W
We performed a randomised pilot trial of PerMIT, a novel decision support tool for genotype-based warfarin initiation and maintenance dosing, to assess its efficacy for improving warfarin management. We prospectively studied 26 subjects to compare PerMIT-guided management with routine anticoagulation service management. CYP2C9 and VKORC1 genotype results for 13 subjects randomly assigned to the PerMIT arm were recorded within 24 hours of enrolment. To aid in INR interpretation, PerMIT calculates estimated loading and maintenance doses based on a patient's genetic and clinical characteristics and displays calculated S-warfarin plasma concentrations based on planned or administered dosages. In comparison to control subjects, patients in the PerMIT study arm demonstrated a 3.6-day decrease in the time to reach a stabilised INR within the target therapeutic range (4.7 vs. 8.3 days, p = 0.015); a 12.8% increase in time spent within the therapeutic interval over the first 25 days of therapy (64.3% vs. 55.3%, p = 0.180); and a 32.9% decrease in the frequency of warfarin dose adjustments per INR measurement (38.3% vs. 57.1%, p = 0.007). Serial measurements of plasma S-warfarin concentrations were also obtained to prospectively evaluate the accuracy of the pharmacokinetic model during induction therapy. The PerMIT S-warfarin plasma concentration model estimated 62.8% of concentrations within 0.15 mg/l. These pilot data suggest that the PerMIT method and its incorporation of genotype/phenotype information may help practitioners increase the safety, efficacy, and efficiency of warfarin therapeutic management.
Mo, Yoonsun; Yam, Felix K
Warfarin, a vitamin K antagonist, has been the only orally available anticoagulant for > 60 years. During the past decade, the U.S. Food and Drug Administration has approved several target-specific oral anticoagulants (TSOACs) for the prophylaxis and treatment of arterial and venous thromboembolism and stroke prevention in patients with nonvalvular atrial fibrillation. These new agents have several advantages over warfarin including more predictable pharmacokinetics and pharmacodynamics, fewer food and drug interactions, and lack of need for routine coagulation monitoring. However, unlike warfarin, currently no antidotes are available to reverse the anticoagulant effect of TSOACs. Specific antidotes for TSOACs may not be needed in most situations due to their short half-life, yet the absence of antidotes for these agents is a concern, especially in emergent situations such as life-threatening major bleeding or nonelective major surgery. Several specific antidotes for TSOACs including idarucizumab, andexanet alfa, and aripazine have been developed and have shown promise in early clinical trials evaluating their efficacy and safety. In this narrative review, the progress made in developing specific antidotes for TSOACs is summarized based on the latest available preclinical and clinical data.
Vandenbroucke, V; Bousquet-Melou, A; De Backer, P; Croubels, S
The first aim of the study was to investigate the pharmacokinetics of eight anticoagulant rodenticides (brodifacoum, bromadiolone, chlorophacinone, coumatetralyl, difenacoum, difethialone, flocoumafen and warfarin) in plasma and liver of the mouse after single oral administration. Eight groups of mice dosed orally with a different anticoagulant rodenticide in a dose equal to one-half the lethal dose 50 (LD(50)), were killed at various times up to 21 days after administration. The eight anticoagulant rodenticides were assayed in plasma and liver by an LC-ESI-MS/MS method. Depending on the compound, the limit of quantification was set at 1 or 5 ng/mL in plasma. In liver, the limit of quantification was set at 250 ng/g for coumatetralyl and warfarin and at 100 ng/g for the other compounds. The elimination half-lives in plasma for first-generation rodenticides were shorter than those for second-generation rodenticides. Coumatetralyl, a first-generation product, had a plasma elimination half-life of 0.52 days. Brodifacoum, a second-generation product, showed a plasma elimination half-life of 91.7 days. The elimination half-lives in liver varied from 15.8 days for coumatetralyl to 307.4 days for brodifacoum. The second aim of the study was to illustrate the applicability of the developed method in a clinical case of a dog suspected of rodenticide poisoning.
Bosch, J; Eikelboom, J W
Fear of bleeding is a common barrier to the use of anticoagulants. Warfarin has been the only oral anticoagulant for more than 60 years and warfarin-related bleeding is reported to be the most common drug-related cause of emergency hospitalization in elderly Americans. Non-vitamin K oral antagonists were introduced five years ago and compared with warfarin are associated with lower risk of intracranial bleeding, and similar or lower case fatality after major bleeding. Despite their superior safety profile, serious bleeding can occur. Most bleeding can be managed with holding the drug, local measures to control the bleeding and transfusion support as required because the NOACs have a relatively short half life and their anticoagulant effect rapidly dissipates. In patients with ongoing bleeding despite supportive measures and in those with life-threatening bleeding, consideration may be given to the use of general hemostatic agents. Experimental and animal evidence suggests that 3 and 4 factor prothrombin complex concentrates can improve hemostasis in the presence of a NOAC and this is reinforced by anecdotal evidence in humans. Specific antidotes are currently in phase 3 trials and could become available in the near future.
Anticoagulation therapy is essential for the effective treatment and secondary prevention of venous thromboembolism (VTE). For many years, anticoagulation for acute VTE was limited to the use of initial parenteral heparin, overlapping with and followed by a vitamin K antagonist. Although highly effective, this regimen has several limitations and is particularly challenging when given in an ambulatory setting. Current treatment pathways for most patients with deep-vein thrombosis typically involve initial hospital or community-based ambulatory care with subsequent follow-up in a secondary care setting. With the introduction of non-vitamin K antagonist oral anticoagulants (NOACs) into routine clinical practice, it is now possible for the initial acute management of patients with deep-vein thrombosis to be undertaken by primary care. As hospital admissions associated with VTE become shorter, primary care will play an increasingly important role in the long-term management of these patients. Although the NOACs can potentially simplify patient management and improve clinical outcomes, primary care physicians may be less familiar with these new treatments compared with traditional therapy. To assist primary care physicians in further understanding the role of the NOACs, this article outlines the main differences between NOACs and traditional anticoagulation therapy and discusses the benefit–risk profile of the different NOACs in the treatment and secondary prevention of recurrent VTE. Key considerations for the use of NOACs in the primary care setting are highlighted, including dose transition, risk assessment and follow-up, duration of anticoagulant therapy, how to minimize bleeding risks, and the importance of patient education and counseling. PMID:27217793
Lippi, Giuseppe; Favaloro, Emmanuel J; Mattiuzzi, Camilla
The recent development and marketing of novel direct oral anticoagulants (DOACs) represents a paradigm shift in the management of patients requiring long-term anticoagulation. The advantages of these compounds over traditional therapy with vitamin K antagonists include a reportedly lower risk of severe hemorrhages and the limited need for laboratory measurements. However, there are several scenarios in which testing should be applied. The potential for drug-to-drug interaction is one plausible but currently underrecognized indication for laboratory assessment of the anticoagulant effect of DOACs. In particular, substantial concern has been raised during Phase I studies regarding the potential interaction of these drugs with some antibiotics, especially those that interplay with permeability glycoprotein (P-gp) and cytochrome 3A4 (CYP3A4). A specific electronic search on clinical trials published so far confirms that clarithromycin and rifampicin significantly impair the bioavailability of dabigatran, whereas clarithromycin, erythromycin, fluconazole, and ketoconazole alter the metabolism of rivaroxaban in vivo. Because of their more recent development, no published data were found for apixaban and edoxaban, or for potential interactions of DOACs with other and widely used antibiotics. It is noteworthy, however, that an online resource based on Food and Drug Administration and social media information, reports several hemorrhagic and thrombotic events in patients simultaneously taking dabigatran and some commonly used antibiotics such as amoxicillin, cephalosporin, and metronidazole. According to these reports, the administration of antibiotics in patients undergoing therapy with DOACs would seem to require accurate evaluation as to whether dose adjustments (personalized or antibiotic class driven) of the anticoagulant drug may be advisable. This might be facilitated by direct laboratory assessments of their anticoagulant effect ex vivo.
Tompson, Alice; Heneghan, Carl; Fitzmaurice, David; Sutton, Stephen; Harrison, Sian; Ward, Alison
Background Clinical trials suggest that oral anticoagulation therapy (OAT) self-monitoring is safe and effective, however little is known about the patient experience of this process. There is a lack of understanding about how best to train and support patients embarking on OAT self-monitoring. Aim To collect in-depth information about patients’ experiences of OAT self-monitoring outside of clinical trial conditions and to produce a set of recommendations on how best to support such patients. Design and setting Semi-structured qualitative interviews with patients who self-monitor and live in England. Method In total, 26 of the 267 (9.7%) who participated in the Cohort study of Anticoagulation Self-Monitoring (CASM) and were still self-monitoring after 12 months’ follow-up were interviewed. Topics discussed included experiences of OAT self-monitoring, healthcare support, training, and decision making. Framework analysis was used. Results Following initial problems using the monitoring device, interviewees described a mostly positive experience. Although less effort was expended attending monitoring appointments with health professionals, effort was required to conduct self-monitoring tests and to interpret and act on the results. Desire to self-manage was variable, especially when dosing advice systems worked promptly and reliably. Interviewees overcame patchy healthcare system knowledge and support of self-monitoring by educating themselves. Family and friends provided support with learning to use the monitor and managing OAT dosage adjustments. Conclusion Better, more-consistent training and health-service support would have alleviated a number of problems encountered by these patients who were self-monitoring. This training and support will become even more important if self-monitoring becomes more accessible to the general population of people on OAT. PMID:26077266
Washam, Jeffrey B; Piccini, Jonathan P
Over the past several years, non-vitamin K oral anticoagulants (NOACs) have been introduced into clinical practice for the treatment of venous thromboembolism and prevention of stroke in patients with nonvalvular atrial fibrillation. Clinical trials have shown these agents to have similar or less risk of major bleeding as compared to warfarin therapy. Moreover, when patients do experience a major bleeding event administration of advanced factor products is rare, and post-bleed outcomes are similar in those receiving a NOAC compared to those receiving warfarin. However, there are situations where urgent reversal of NOAC anticoagulation would be desirable. The following review focuses on the outcomes and management strategies for patients experiencing a major bleed with warfarin or NOAC agents and describes the rationale for the development of therapies capable of targeted NOAC-reversal.
Ebright, Joseph; Mousa, Shaker A
Anticoagulants have been used in clinical practice for more than 50 years. Their indications expand, as more people are diagnosed each year with atrial fibrillation and venous thromboembolism. Vitamin K antagonists have been the most popular choice due to their effectiveness and their ability to reverse bleeding using a known antidote; oral and intravenous vitamin K have long been known to reverse the effects of warfarin. With new classes of anticoagulants making their way onto the market, such as factor Xa inhibitors (rivaroxaban, apixaban) and direct thrombin inhibitors (dabigatran), the need for new reversal agents is paramount. Patients tend to be more receptive to these medications because they do not require routine blood monitoring, can be used at fixed doses, and do not have major drug or food interactions. Antidotes for these medications have shown promise in animal models and are currently in clinical trials.
Atrial fibrillation (AF) is a significant problem for the aging population and remains a major factor underlying stroke risk. Warfarin anticoagulation has been proven effective for stroke prevention in AF, but can be difficult to manage and requires frequent monitoring. The non-vitamin K antagonist oral anticoagulants (NOACs) have been shown to be as effective as warfarin for stroke prevention in nonvalvular AF (NVAF) and are associated with a reduced risk of bleeding compared with warfarin. Dabigatran, rivaroxaban, apixaban, and edoxaban have been approved in the USA for reducing the risk of stroke in patients with NVAF. In this article, AF risk assessment is discussed and NOAC phase III clinical trials for the prevention of stroke and systemic embolic events are reviewed. Further, differences in stroke and bleeding outcomes between NOACs are highlighted, the use of NOACs for cardioversion and special patient populations is discussed, and management considerations for patients with AF are reviewed.
Fitzmaurice, D A; Hobbs, F D; Murray, E T; Bradley, C P; Holder, R
BACKGROUND: Increasing indications for oral anticoagulation has led to pressure on general practices to undertake therapeutic monitoring. Computerized decision support (DSS) has been shown to be effective in hospitals for improving clinical management. Its usefulness in primary care has previously not been investigated. AIM: To test the effectiveness of using DSS for oral anticoagulation monitoring in primary care by measuring the proportions of patients adequately controlled, defined as within the appropriate therapeutic range of International Normalised Ratio (INR). METHOD: All patients receiving warfarin from two Birmingham inner city general practices were invited to attend a practice-based anticoagulation clinic. In practice A all patients were managed using DSS. In practice B patients were randomized to receive dosing advice either through DSS or through the local hospital laboratory. Clinical outcomes, adverse events and patient acceptability were recorded. RESULTS: Forty-nine patients were seen in total. There were significant improvements in INR control from 23% to 86% (P > 0.001) in the practice where all patients received dosing through DSS. In the practice where patients were randomized to either DSS or hospital dosing, logistic regression showed a significant trend for improvement in intervention patients which was not apparent in the hospital-dosed patients (P < 0.001). Mean recall times were significantly extended in patients who were dosed by the practice DSS through the full 12 months (24 days to 36 days) (P = 0.033). Adverse events were comparable between hospital and practice-dosed patients, although a number of esoteric events occurred. Patient satisfaction with the practice clinics was high. CONCLUSION: Computerized DSS enables the safe and effective transfer of anticoagulation management from hospital to primary care and may result in improved patient outcome in terms of the level of control, frequency of review and general acceptability. PMID
Turagam, Mohit K; Velagapudi, Poonam; Flaker, Greg C
Stroke prevention in elderly atrial fibrillation patients remains a challenge. There is a high risk of stroke and systemic thromboembolism but also a high risk of bleeding if anticoagulants are prescribed. The elderly have increased chronic kidney disease, coronary artery disease, polypharmacy, and overall frailty. For all these reasons, anticoagulant use is underutilized in the elderly. In this manuscript, the benefits of non-vitamin K antagonist oral anticoagulants compared with warfarin in the elderly patient population with multiple comorbid conditions are reviewed. PMID:26366064
New oral anticoagulants offer several potential advantages including oral administration, fixed doses, no regular coagulation monitoring and dose adjustment and wide therapeutic index. The results from clinical studies for prevention and treatment of venous thromboembolism and for stroke prevention in patients with atrial fibrillation show that these agents are at least as effective as or superior to currently available therapies depending on the molecules and dose regimen. Physicians will have to make choices among available new agents taking into account their pharmacokinetic properties, half-life, route of elimination and patient comorbidities. But the use of these new agents in daily practice raises some issues such as temporary discontinuation in patients undergoing invasive procedures and management of patients with bleeding in the absence of specific antidote. New oral anticoagulants should be used with caution in daily practice in special populations such as elderly patients, patients with renal impairment and patients with cancer. Primary care physicians will have to play a role in monitoring and evaluating the long-term efficacy and safety of these agents in daily practice.
Gómez-Outes, Antonio; Suárez-Gea, Ma Luisa; Lecumberri, Ramón; Terleira-Fernández, Ana Isabel; Vargas-Castrillón, Emilio
In recent years, several direct-acting oral anticoagulants (DOAC) have become available for use in Europe and other regions in indications related to prophylaxis and treatment of venous and arterial thromboembolism. They include the oral direct thrombin inhibitor dabigatran etexilate (Pradaxa, Boehringer Ingelheim) and the oral direct FXa inhibitors rivaroxaban (Xarelto, Bayer HealthCare), apixaban (Eliquis, Bristol-Myers Squibb), and edoxaban (Lixiana/Savaysa, Daiichi-Sankyo). The new compounds have a predictable dose response and few drug-drug interactions (unlike vitamin k antagonists), and they do not require parenteral administration (unlike heparins). However, they accumulate in patients with renal impairment, lack widely available monitoring tests for measuring its anticoagulant activity, and no specific antidotes for neutralization in case of overdose and/or severe bleeding are currently available. In this review, we describe the pharmacology of the DOAC, the efficacy, and safety data from pivotal studies that support their currently approved indications and discuss the postmarketing experience available. We also summarize practical recommendations to ensure an appropriate use of the DOAC according to existing data. Finally, we discuss relevant ongoing studies and future perspectives.
Jones, W J; Francis, J J
Softgels, which contain a liquid formulation of a drug, often provide clinical benefit over other solid oral dosage forms and may represent an attractive alternative to them. A consumer preference survey of softgels versus other solid forms investigated four areas: (1) identification of various dosage forms; (2) perception of therapeutic benefit (easiest to swallow, faster-acting, work longer); (3) impact of individual product characteristics on overall product selection; and (4) market impact in terms of premiums consumers would pay on the basis of dosage form. The 300 survey participants strongly preferred clear softgels over other dosage forms in virtually every area. Softgels were perceived as easy to swallow and fast-acting, with a duration of action second only to that of a two-piece capsule. Overall preference was driven by ease of swallowing, and softgels were rated first by the majority of respondents. Consumers would be interested in various products if these were available as softgels rather than in their current oral dosage forms and may be willing to pay a premium for softgel products. This survey confirms consumer preferences for particular dosage forms and for softgels over other solid forms. Pharmaceutical scientists and marketers should consider softgels as alternative dosage forms when developing new compounds or considering life-cycle management of existing products.
Warfarin has a long history of benefit and has become the gold standard medication for the prevention of ischemic stroke in patients with atrial fibrillation. Nevertheless, it is far from perfect and there is no doubt that new drugs must be found to replace warfarin. The new oral anticoagulants that are on the market or awaiting approval or under research offer some benefits but not enough to replace warfarin until results of additional studies can show an adequate balance between effectiveness/safety and cost/benefit. There are several issues concerning the new oral anticoagulants. It is essential that the effect of any anticoagulant can be measured in plasma. But to date, there is no test to assess the effect or therapeutic range for the new oral anticoagulants. There is no antidote to neutralize the action of the new drugs in cases of bleeding or when acute surgical intervention is necessary. Dabigatran requires dose adjustment in patients with moderate renal impairment and is contraindicated in patients with severe renal failure. Rivaroxaban should be used with caution in patients with severe renal impairment. Apixaban excretion is also partly dependent on renal function, although the impact of renal insufficiency has not yet been determined. How anticoagulant bridging can be done before surgery has not yet been established. In conclusion, although thousands of patients have been treated in phase III studies, additional data are necessary before conclusions can be drawn on the potential for these new anticoagulant drugs to replace warfarin in patients with atrial fibrillation. PMID:21794130
Rabkin, Simon W; Moe, Gordon
According to recent guidelines for atrial fibrillation (AF) management, the presence of hypertension warrants anticoagulation, often involving the use of newer oral anticoagulants (NOACs). To discuss this idea, we posited the case against this proposition. We note that the data on hypertension that formulated the most commonly used Congestive Heart Failure, Hypertension, Age, Diabetes, Stroke/Transient Ischemic Attack (CHADS2) risk algorithm were not clearly defined and that there are insufficient data that hypertension in the presence of AF produces a meaningful incremental increase in stroke risk over and above the stroke risk increase for hypertension alone. Data exist that persons younger than 65 years of age with only 1 stroke risk factor such as hypertension, have a very small stroke risk. We further note that there are no quantitative data to allow clinicians to decide the level of blood pressure that meaningfully increases stroke risk in AF. Furthermore, there are insufficient data on the blood pressure level at which the risk of cerebral hemorrhage outweighs the risk of cardioembolic events. Clinical trials of NOACs in AF did not usually include hypertension as the only entry criteria. Another issue is the recent changes in the level of blood pressure for the diagnosis of hypertension based on home and ambulatory blood pressure measurement, which were not used to construct either stroke risk algorithms or entry criteria for NOAC clinical trials. These considerations highlight some of the complexities of using hypertension as a sole criterion for decision-making for anticoagulation in AF.
Douxfils, Jonathan; Mani, Helen; Minet, Valentine; Devalet, Bérangère; Chatelain, Bernard; Dogné, Jean-Michel; Mullier, François
Non-VKA oral anticoagulants (NOACs) have now widely reached the lucrative market of anticoagulation. While the marketing authorization holders claimed that no routine monitoring is required and that these compounds can be given at fixed doses, several evidences arisen from the literature tend to demonstrate the opposite. New data suggests that an assessment of the response at the individual level could improve the benefit-risk ratio of at least dabigatran. Information regarding the association of rivaroxaban and apixaban exposure and the bleeding risk is available in the drug approval package on the FDA website. These reviews suggest that accumulation of these compounds increases the risk of experiencing a bleeding complication. Therefore, in certain patient populations such as patients with acute or chronic renal impairment or with multiple drug interactions, measurement of drug exposure may be useful to ensure an optimal treatment response. More specific circumstances such as patients experiencing a haemorrhagic or thromboembolic event during the treatment duration, patients who require urgent surgery or an invasive procedure, or patient with a suspected overdose could benefit from such a measurement. This paper aims at providing guidance on how to best estimate the intensity of anticoagulation using laboratory assays in daily practice.
Salmonson, Tomas; Dogné, Jean-Michel; Janssen, Heidi; Garcia Burgos, Juan; Blake, Paul
In contrast to vitamin K antagonists, no routine coagulation monitoring is required in patients taking non-vitamin-K oral anticoagulants (NOACs). However, dosing must take into account factors such as patient age, renal function, and accompanying haemorrhagic risk. There has been considerable debate about when laboratory measurement might be appropriate and which tests should be used. A workshop at the European Medicines Agency recently discussed the evidence about laboratory measurement from formal studies, clinical experience, and the multiple perspectives on NOAC treatment, and considered how our knowledge might be further enhanced. PMID:28025213
Nie, Haichen; Byrn, Stephen R; Zhou, Qi Tony
Using pharmaceutical salts in solid dosage forms can raise stability concerns, especially salt dissociation which can adversely affect the product performance. Therefore, a thorough understanding of the salt instability encountered in solid state formulations is imperative to ensure the product quality. The present article uses the fundamental theory of acid base, ionic equilibrium, relationship of pH and solubility as a starting point to illustrate and interpret the salt formation and salt disproportionation in pharmaceutical systems. The criteria of selecting the optimal salt form and the underlying theory of salt formation and disproportionation are reviewed in detail. Factors influencing salt stability in solid dosage forms are scrutinized and discussed with the case studies. In addition, both commonly used and innovative strategies for preventing salt dissociations in formulation, on storage, and during manufacturing will be suggested herein. This article will provide formulation scientists and manufacturing engineers an insight into the mechanisms of salt disproportionation and salt formation, which can help them avoid and solve the instability issues of pharmaceutical salts in the product design.
Zhang, Geoff G Z; Law, Devalina; Schmitt, Eric A; Qiu, Yihong
The quality and performance of a solid oral dosage form depends on the choice of the solid phase, the formulation design, and the manufacturing process. The potential for process-induced solid phase transformations must be evaluated during design and development of formulations and manufacturing processes. This article briefly reviews the basic principles of polymorphism, defines the classes of phase transformation and the underlying transformation mechanisms, and discusses respective kinetic factors. The potential phase transformations associated with common unit operations employed in manufacturing solid oral dosage forms are highlighted. Specific examples are given to illustrate the importance of solid phases, and process-induced phase transitions in formulation and process development.
Kortejärvi, H; Yliperttula, M; Dressman, J B; Junginger, H E; Midha, K K; Shah, V P; Barends, D M
Literature and experimental data relevant to the decision to allow a waiver of in vivo bioequivalence testing for the approval of immediate release (IR) solid oral dosage forms containing ranitidine hydrochloride are reviewed. According to the current Biopharmaceutics Classification System (BCS), ranitidine hydrochloride should be assigned to Class III. However, based on its therapeutic and therapeutic index, pharmacokinetic properties and data related to the possibility of excipient interactions, a biowaiver can be recommended for IR solid oral dosage forms that are rapidly dissolving and contain only those excipients as reported in this study.
Oral drug delivery is a non-invasive and therefore a very convenient route of administration. Orally disintegrating dosage forms, like soluble films and (mini-)tablets, appear promising for use in the pediatric population. New guidance for the development of pediatric medicines has been published, which provides considerations on how pediatric products should be designed. However, most of the considerations leave a lot of room for interpretations. Bearing in mind the different aspects discussed in the latest guideline, the use of orally disintegrating films and tablets, in particular, small-sized tablets, is discussed and reflected upon by providing evidence from the scientific literature. The available dosage forms for children are various and examples of currently licensed products for use in the pediatric population were compiled. Aspects such as the appropriateness for pediatrics, the choice of excipients, the opportunities for modified drug release preparations or fixed-dose combinations, the acceptability and palatability, and also limitations were discussed with respect to the new dosage forms of orally disintegrating films and mini-tablets. This paper points out that innovation in pediatric medicines are planned and should be encouraged; however, supported by the regulatory guidance, only general considerations are provided. Nevertheless, the guideline summarizes multiple points to consider during the development of medicines for pediatric use. Considering the scientific evidence and the regulatory guidance, orally disintegrating dosage forms, like soluble films and (mini-)tablets, offer an innovative solution for pediatric drug delivery.
Tran, Arlene; Cheng-Lai, Angela
For more than 5 decades, warfarin has been the mainstay of therapy when oral anticoagulation is required. It has been shown to be effective in the prevention as well as treatment of various thromboembolic disorders. However, drawbacks of warfarin, such as time-consuming requirements for frequent international normalized ratio monitoring, as well as drug and food interactions, have encouraged the development of alternative oral agents. One such agent, dabigatran, has risen up to the challenge. Due to its predictable anticoagulation response, dabigatran does not require routine anticoagulation monitoring. Another advantage dabigatran has over warfarin is its more favorable drug and food interaction profiles. Dabigatran was shown to be noninferior to warfarin in studies evaluating the prevention of stroke and systemic embolism in patients with atrial fibrillation, thus leading to the US Food and Drug Administration approval for this indication. Dabigatran has also demonstrated efficacy in the prevention of venous thromboembolism in patients undergoing total hip or knee replacement surgery as well as the prevention of recurrent venous thromboembolism, although these are not current Food and Drug Administration-approved indications. The safety profile appears to be similar to warfarin with regards to overall bleeding risk, though the risk for gastrointestinal bleeds was higher in patients on dabigatran 150 mg twice daily. Disadvantages of dabigatran may include a higher frequency of dyspepsia compared with warfarin, lack of dosing information in severe renal impairment, possible missed opportunities for periodic health examinations and interventions due to elimination of regular physician's visit for international normalized ratio monitoring, and drug costs. This article provides an overview of the clinical studies, pharmacokinetic profile, adverse effects, drug interactions as well as advantages and disadvantages associated with dabigatran.
Weitz, Jeffrey I; Pollack, Charles V
Non-vitamin K antagonist oral anticoagulants (NOACs) are increasingly used in the prevention and treatment of venous thromboembolism and in the prevention of stroke in patients with non-valvular atrial fibrillation. In phase III clinical trials and meta-analyses, the NOACs were at least as effective as vitamin K antagonists (VKAs) and were associated with a similar or lower incidence of major bleeding, including consistent and significant decreases in intracranial bleeding, although with an increase in gastrointestinal bleeding for some agents compared with VKAs. Subsequent real-world evidence supports these outcomes. Despite this, physicians have concerns about serious bleeding or emergencies because there are no specific reversal agents for the NOACs. However, in clinical trials, patients receiving NOACs generally had similar or better outcomes after these events than those taking VKAs. As with any bleeding, anticoagulant-related bleeding should first be stratified according to severity and location; risk can be minimised by ongoing assessment. Management protocols for NOAC-related bleeding are similar to those for VKAs but should take into account the pharmacological profile of the specific drug. Because of their short half-lives, NOAC-related mild bleeding can often be controlled by temporarily withholding treatment. More severe bleeding requires standard escalating haemodynamic support measures, and non-specific reversal agents can be considered in life-threatening situations, based on limited clinical data. Specific and rapid reversal agents are not currently available for any oral anticoagulant and restoration of coagulation may not necessarily lead to better outcomes. Nevertheless, specific NOAC reversal agents are in development and show promise in healthy volunteers.
Eckman, Mark H
Until recently, vitamin K antagonists, warfarin being the most commonly used agent in the United States, have been the only oral anticoagulant therapies available to prevent stroke in patients with atrial fibrillation (AF). In the last 5 years four new, non-vitamin K oral anticoagulants, the so-called NOACs or novel oral anticoagulants, have come to market and been approved by the Federal Drug Administration. Despite comparable if not superior efficacy in preventing AF-related stroke, and generally lower risks of major hemorrhage, particularly intracranial bleeding, the uptake of these agents has been slow. A number of barriers stand in the way of the more widespread use of these novel agents. Chief among them is concern about the lack of antidotes or reversal agents. Other concerns include the need for strict medication adherence, since missing even a single dose can lead to a non-anticoagulated state; out-of-pocket costs for patients; the lack of easily available laboratory tests to quantitatively assess the level of anticoagulant activity when these agents are being used; contraindications to use in patients with severe chronic kidney disease; and black-box warnings about the increased risk of thromboembolic events if these agents are discontinued prematurely. Fortunately, a number of reversal agents are in the pipeline. Three reversal agents, idarucizumab, andexanet alfa, and aripazine, have already progressed to human studies and show great promise as either antidotes for specific drugs or as universal reversal agents. The availability of these reversal agents will likely increase the clinical use of the non-vitamin K oral anticoagulants. In light of the many complex and nuanced issues surrounding the choice of an optimal anticoagulant for any AF patient, a patient-centered/shared decision-making approach will be useful.
Sibbing, D; Spannagl, M
Oral anticoagulants and platelet receptor blockers are widely used in clinical practice with the aim of reducing the risk of thrombotic complications in patients with cardiovascular diseases. Their regular intake and adequate antithrombotic action is vital and this is way numerous assays have been developed for laboratory testing and monitoring of these agents. Available assays can be stratified into pharmacokinetic and pharmacodynamic assays. Such assays are increasingly used in clinical routine and their daily use is triggered by the advent of the novel direct oral anticoagulants (DOACs) as an alternative for vitamin K antagonist (VKA) treatment, which are dabigatran, rivaroxaban and apixaban, and by the advent of prasugrel or ticagrelor as an alternative for clopidogrel with regard to platelet P2Y12 receptor inhibition. In this review the most important and most commonly used laboratory assays are summarized as well as their clinical implications with the focus on DOACs as an alternative for VKAs and the different P2Y12 receptor blockers for antiplatelet treatment.
Diener, Hans-Christoph; Kleinschnitz, Christoph
Non-vitamin-K oral anticoagulants (NOACs) represent a major advance in the prevention of stroke in patients with atrial fibrillation (AF), offering a similar, if not superior, efficacy and safety profile and several practical advantages over oral vitamin K antagonists (VKAs). The rapid onset of action of the NOACs, their relatively short half-live, and the availability of specific reversal agents may be advantageous when managing acute ischemic strokes, and in the post-stroke, post-transient ischemic attack, and post-intracranial hemorrhage settings. In this review article, we offer practical guidance on the use of NOACs in these settings, focusing on managing the acute event and on initiating or resuming anticoagulation for secondary prevention. We also assess the use of NOACs to prevent stroke and bleeding in patients with AF who have chronic kidney disease, are elderly, or cognitively impaired, and we offer guidance on optimizing the use of NOACs and VKAs in these patient groups in the absence of evidence-based guidelines. PMID:27165264
Bujanda, L; Sarasqueta, C; Lanas, Á; Quintero, E; Cubiella, J; Hernandez, V; Morillas, J D; Perez-Fernández, T; Salas, D; Andreu, M; Carballo, F; Bessa, X; Portillo, I; Jover, R; Balaguer, F; Cosme, A; Castells, A
Background: We aimed to evaluate whether oral anticoagulants (OACs) alter faecal immunochemical test (FIT) performance in average-risk colorectal cancer (CRC) screening. Methods: Individuals aged 50–69 years were invited to receive one FIT sample (cutoff 75 ng ml–1) between November 2008 and June 2011. Results: Faecal immunochemical test was positive in 9.3% (21 out of 224) of users of OAC and 6.2% (365 out of 5821) of non-users (P-trend=0.07). The positive predictive value (PPV) for advanced neoplasia (AN) in non-users was 50.4% vs 47.6% in users (odds ratio, 0.70; 95% CI, 0.3–1.8; P=0.5). The PPV for AN in OAC more antiplatelets (aspirin or clopidogrel) was 75% (odds ratio, 2; 95% CI, 0.4–10.8; P=0.4). Conclusions: Oral anticoagulant did not significantly modify the PPV for AN in this population-based colorectal screening program. The detection rate of advanced adenoma was higher in the combination OAC more antiplatelets. PMID:24496455
Peacock, W Frank; Rafique, Zubaid; Singer, Adam J
Nonvalvular atrial fibrillation- (NVAF-) related stroke and venous thromboembolism (VTE) are cardiovascular diseases associated with significant morbidity and economic burden. The historical standard treatment of VTE has been the administration of parenteral heparinoid until oral warfarin therapy attains a therapeutic international normalized ratio. Warfarin has been the most common medication for stroke prevention in NVAF. Warfarin use is complicated by a narrow therapeutic window, unpredictable dose response, numerous food and drug interactions, and requirements for frequent monitoring. To overcome these disadvantages, direct-acting oral anticoagulants (DOACs)-dabigatran, rivaroxaban, apixaban, and edoxaban-have been developed for the prevention of stroke or systemic embolic events (SEE) in patients with NVAF and for the treatment of VTE. Advantages of DOACs include predictable pharmacokinetics, few drug-drug interactions, and low monitoring requirements. In clinical studies, DOACs are noninferior to warfarin for the prevention of NVAF-related stroke and the treatment and prevention of VTE as well as postoperative knee and hip surgery VTE prophylaxis, with decreased bleeding risks. This review addresses the practical considerations for the emergency physician in DOAC use, including dosing recommendations, laboratory monitoring, anticoagulation reversal, and cost-effectiveness. The challenges of DOACs, such as the lack of specific laboratory measurements and antidotes, are also discussed.
Krüger, Thilo; Brandenburg, Vincent; Schlieper, Georg; Marx, Nikolaus; Floege, Jürgen
End-stage renal disease (ESRD) patients exhibit an increased risk of bleeding compared with non-chronic kidney disease (CKD) patients due to uraemic platelet dysfunction, altered vessel architecture and other factors. This renders any long-term oral anticoagulation potentially difficult. While there is little doubt that ESRD patients with recurrent thromboembolism or a mechanical cardiac valve should receive vitamin K antagonists (coumarins), the use of coumarins in ESRD patients with atrial fibrillation is a matter of debate. In non-CKD patients, current guidelines strongly recommend the use of oral anticoagulants for stroke prophylaxis in atrial fibrillation if certain risk factors are present (CHA2DS2-VASc score). This recommendation is often extrapolated to patients with advanced CKD or ESRD but data supporting this practice are weak to absent. Besides an increased bleeding risk in ESRD patients, coumarins will also accelerate cardiovascular calcification and are potent risk factors for the development of calcific uraemic arteriolopathy (calciphylaxis). Novel coumarin alternatives such as direct thrombin inhibitors are promising but none is currently approved for use in ESRD patients. Whether interventional treatment strategies such as atrial appendage occlusion are safe and effective options in advanced CKD is also as yet unresolved. This review attempts to balance the potential risks and benefits of coumarin usage in ESRD patients and to give the best possible recommendations for everyday patient care.
Peacock, W. Frank; Rafique, Zubaid; Singer, Adam J.
Nonvalvular atrial fibrillation- (NVAF-) related stroke and venous thromboembolism (VTE) are cardiovascular diseases associated with significant morbidity and economic burden. The historical standard treatment of VTE has been the administration of parenteral heparinoid until oral warfarin therapy attains a therapeutic international normalized ratio. Warfarin has been the most common medication for stroke prevention in NVAF. Warfarin use is complicated by a narrow therapeutic window, unpredictable dose response, numerous food and drug interactions, and requirements for frequent monitoring. To overcome these disadvantages, direct-acting oral anticoagulants (DOACs)—dabigatran, rivaroxaban, apixaban, and edoxaban—have been developed for the prevention of stroke or systemic embolic events (SEE) in patients with NVAF and for the treatment of VTE. Advantages of DOACs include predictable pharmacokinetics, few drug-drug interactions, and low monitoring requirements. In clinical studies, DOACs are noninferior to warfarin for the prevention of NVAF-related stroke and the treatment and prevention of VTE as well as postoperative knee and hip surgery VTE prophylaxis, with decreased bleeding risks. This review addresses the practical considerations for the emergency physician in DOAC use, including dosing recommendations, laboratory monitoring, anticoagulation reversal, and cost-effectiveness. The challenges of DOACs, such as the lack of specific laboratory measurements and antidotes, are also discussed. PMID:27293895
Atrial fibrillation (AF) is strongly associated with cardioembolic stroke, and thromboprophylaxis is an established means of reducing stroke risk in patients with AF. Oral vitamin K antagonists such as warfarin have been the mainstay of therapy for stroke prevention in patients with AF. However, they are associated with a number of limitations, including excessive bleeding when not adequately controlled. Antiplatelet agents do not match vitamin K antagonists in terms of their preventive efficacy. Dual-antiplatelet therapy (clopidogrel and acetylsalicylic acid) or combined antiplatelet-vitamin K antagonist therapy in AF has also failed to provide convincing evidence of their additional benefit over vitamin K antagonists alone. Novel oral anticoagulants, including the direct thrombin inhibitor dabigatran and direct Factor Xa inhibitors such as rivaroxaban, apixaban, and edoxaban, have now been approved or are currently in late-stage clinical development in AF. These newer agents may provide a breakthrough in the optimal management of stroke risk.
Introduction Today, we frequently find patients taking oral anticoagulant therapy (OAT), a prophylaxis against the occurrence of thromboembolic events. An oral surgeon needs to know how to better manage such patients, in order to avoid hemorrhagic and thromboembolic complications. Materials and methods A group of 193 patients (119 men aged between 46 and 82 and 74 women aged between 54 and 76) undergoing OAT for more than 5 years were managed with a standardized management protocol and a 2-months follow-up. The aim of the present study was to apply a protocol, which could provide a safe intra- and postoperative management of patients on OAT. Results Among the 193 patients, only 2 had postoperative complications. Conclusions We think that the protocol used in the present study can be used for complete safety in the treatment of this type of patients. PMID:21771331
Alegret, Josep M.; Viñolas, Xavier; Arias, Miguel A.; Martínez-Rubio, Antoni; Rebollo, Pablo; Ràfols, Carles; Martínez-Sande, José L.
New oral anticoagulants (NOAC) have demonstrated their efficacy as an alternative to vitamin K antagonists (VKA) in the prophylaxis of cardioembolic events in patients with atrial fibrillation (AF). However, evidence on the benefits of NOAC in health-related quality of life (HRQoL) is lacking.We evaluated changes in HRQoL related to oral anticoagulation therapy employing a specific questionnaire in a cohort of 416 patients with AF undergoing electrical cardioversion. In terms of HRQoL, we observed a progressive adaptation to treatment with VKA; satisfaction with NOAC remained constant. Older age, higher left ventricular ejection fraction and NOAC were associated with better HRQoL. PMID:24843316
... HUMAN SERVICES Food and Drug Administration 21 CFR Parts 520 and 558 Oral Dosage Form New Animal Drugs; Nicarbazin; Oclacitinib; Zilpaterol AGENCY: Food and Drug Administration, HHS. ACTION: Final rule. SUMMARY: The Food and Drug Administration (FDA) is amending the animal drug regulations to reflect...
... HUMAN SERVICES Food and Drug Administration 21 CFR Part 520 Oral Dosage Form New Animal Drugs... Administration (FDA) is amending the animal drug regulations to reflect approval of an original abbreviated new animal drug application (ANADA) filed by Cross Vetpharm Group, Ltd. The ANADA provides for use...
... HUMAN SERVICES Food and Drug Administration 21 CFR Part 520 Oral Dosage Form New Animal Drugs; Change of... Administration (FDA) is amending the animal drug regulations to reflect a change of sponsor for a new animal drug.... 801-808. List of Subjects in 21 CFR Part 520 Animal drugs. Therefore, under the Federal Food,...
... / Thursday, August 11, 2011 / Rules and Regulations#0;#0; ] DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration 21 CFR Part 520 Oral Dosage Form New Animal Drugs; Change of Sponsor... for five new animal drug applications (NADAs) from Fort Dodge Animal Health, Division of...
... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration 21 CFR Part 520 Oral Dosage Form New Animal Drugs; Change of... hydrochloride soluble powder from Teva Animal Health, Inc., to Cross Vetpharm Group, Ltd. DATES: This rule...
Reppas, Christos; Friedel, Horst-Dieter; Barker, Amy R; Buhse, Lucinda F; Cecil, Todd L; Keitel, Susanne; Kraemer, Johannes; Morris, J Michael; Shah, Vinod P; Stickelmeyer, Mary P; Yomota, Chikako; Brown, Cynthia K
Biorelevant in vitro performance testing of orally administered dosage forms has become an important tool for the assessment of drug product in vivo behavior. An in vitro performance test which mimics the intraluminal performance of an oral dosage form is termed biorelevant. Biorelevant tests have been utilized to decrease the number of in vivo studies required during the drug development process and to mitigate the risk related to in vivo bioequivalence studies. This report reviews the ability of current in vitro performance tests to predict in vivo performance and generate successful in vitro and in vivo correlations for oral dosage forms. It also summarizes efforts to improve the predictability of biorelevant tests. The report is based on the presentations at the 2013 workshop, Biorelevant In Vitro Performance Testing of Orally Administered Dosage Forms, in Washington, DC, sponsored by the FIP Dissolution/Drug Release Focus Group in partnership with the American Association of Pharmaceutical Scientists (AAPS) and a symposium at the AAPS 2012 Annual meeting on the same topic.
Over the past few years, three novel oral anticoagulants, dabigatran, rivaroxaban, and apixaban, have been approved in the USA and Europe to reduce the risk of stroke or systemic embolism in patients with nonvalvular atrial fibrillation, and the results of a Phase III trial for a fourth novel oral anticoagulant, edoxaban, have recently been published. The aim of this review is to examine this indication from a clinician’s perspective, highlighting efficacy and safety results from the major trials with these novel oral agents. Clinical issues regarding bleeding, monitoring, and reversal are discussed, along with requirements to consider when interrupting treatment with a novel oral anticoagulant for the purpose of transitioning to another anticoagulant and prior to cardioversion, ablation, percutaneous coronary intervention, or emergency surgery. The cost-effectiveness of each of the approved novel oral anticoagulants is reviewed, and the author provides recommendations for selecting appropriate patients for these agents. PMID:25187724
Virdee, Mandeep S; Stewart, Derek
Background Updated evidence-based guidelines for the management of atrial fibrillation (AF) necessitate patient review, particularly with respect to oral anticoagulants, to ensure maximum health gain around stroke prophylaxis. Objective To quantify the level of anticoagulation utilisation in patients with a CHA2DS2-VASc ≥1/≥2 (male/female) according to evidence-based guidelines and to assess the impact of a pharmacist-led intervention to optimise therapy. Setting Fifteen general medical practices in Liverpool, North-West England with a practice population of 99,129. Method GRASP-AF software was employed to interrogate patient electronic medical records to identify and risk stratify AF patients (using CHA2DS2-VASc). A pharmacist then reviewed the medical records of those of patients not anticoagulated and with a CHA2DS2-VASc ≥1/≥2 (male/female). Recommendations were discussed with a general practitioner (GP) and those patients in whom the need for anticoagulation was agreed were invited for a consultation with either the pharmacist or GP and therapy optimised where appropriate. The GPs were responsible for managing those patients referred for diagnosis confirmation or further specialist opinion. Main outcome measure Proportion of patients eligible/not eligible for anticoagulation; proportions in whom anticoagulants initiated, refused, antiplatelets discontinued. Results Five hundred and twenty-three patients (31% of patients identified with AF and a CHA2DS2-VASc ≥1/≥2 (male/female)) were not receiving an anticoagulant (26 subsequently died or left the practice leaving 497). Three hundred and eighty-two (77%) pharmacist recommendations to a GP were agreed without modification. Following outcomes of diagnostic investigations and specialist referrals, 202 (41%) patients were candidates for anticoagulation, 251 (51%) were not eligible for anticoagulation, 103 (21%) were anticoagulated (56 warfarin, 47 DOAC). Conclusion A pharmacist-led intervention re
Stosik, A G; Junginger, H E; Kopp, S; Midha, K K; Shah, V P; Stavchansky, S; Dressman, J B; Barends, D M
Literature data are reviewed relevant to the decision for a biowaiver of immediate release (IR) solid oral dosage forms containing metoclopramide hydrochloride. In addition, new solubility data, obtained under Biopharmaceutics Classification System (BCS) conditions are presented. Metoclopramide HCl is conservatively assigned to BCS Class III. Taken also into consideration excipient interactions reported in metoclopramide drug products, its pharmacokinetic properties and therapeutic use and therapeutic index, a biowaiver can be recommended when: (a) the test product contains only excipients present also in metoclopramide HCl containing IR solid oral drug products approved in ICH or associated countries, for instance as presented in this paper, (b) in amounts in normal use in IR solid oral dosage forms, and (c) the test product and the comparator both comply with the criteria for very rapidly dissolving.
Purrucker, Jan C.; Haas, Kirsten; Wolf, Marcel; Rizos, Timolaos; Khan, Shujah; Kraft, Peter; Poli, Sven; Dziewas, Rainer; Meyne, Johannes; Palm, Frederick; Jander, Sebastian; Möhlenbruch, Markus; Heuschmann, Peter U.; Veltkamp, Roland
Background and Purpose To evaluate the frequency and outcome of haemorrhagic transformation (HT) after ischaemic stroke in patients treated with non-vitamin K antagonist oral anticoagulants (NOACs). Methods Patients with stroke on treatment with a NOAC were prospectively enrolled in this multicentre observational study between February 2012 and 2015. Brain imaging at admission and follow-up imaging until day 7 were reviewed for HT. Functional outcome was assessed by the modified Rankin scale (mRS) before the index event, at discharge, and at 3-months. Results 231 patients without recanalisation therapy (no-RT), and 32 patients with RT were eligible for analysis. Any HT was present at admission in 9/231 no-RT patients (3.9%, 95% CI 2.0 to 7.3) and in none of the patients with RT. In patients with follow-up imaging (no-RT, n=129, and RT, n=32), HT was present in 14.0% (no-RT; 95% CI, 8.9 to 21.1), and 40.6% (RT, 95% CI, 25.5 to 57.8), respectively. After adjustment for stroke severity, this difference between the no-RT and RT groups became non-significant. Symptomatic ICH was observed in 1 patient per group. HT was not associated with unfavourable outcome (mRS 3-6) at 3-months in multivariable analysis. Resumption of OAC after stroke was delayed in patients with HT compared to those without (15 d [IQR, 5–26] vs. 1 d [0–4], P<0.001). Conclusions The frequency and severity of HT after stroke on NOAC appears similar to previous reports for vitamin K antagonists and no anticoagulation. Whether asymptomatic HT should delay resumption of preventive anticoagulation requires further investigation. PMID:28178406
Wening, Klaus; Breitkreutz, Jörg
There is an evident need for solid oral dosage forms allowing patients' tailor-made dosing due to variations in metabolization or small therapeutic indexes of drug substances. The objective of this work is the development of a device equipped with a novel solid dosage form, containing carvedilol as model drug, for the delivery of monolithical drug carriers in individual doses. The device was developed and constructed enabling an exact feed rate and dose adjustment by a cutting mechanism. A twin-screw extruder was used for producing cylindrical solid dosage forms. Divided doses were characterized by mass variation, cutting behavior and drug dissolution in order to investigate their applicability for practical use. Different formulations could be extruded obtaining straight cylindrical rods, which are divisible in exact slices by using the novel device. Forces below 20 N were needed to divide doses which comply with pharmacopoeial specification "conformity of mass". The developed formulations exhibit a sustained release of carvedilol within a range from 7 up to 16 h. A novel system consisting of a device and a cylindrical dosage form was developed. Patients' individual doses can be applied as monolithical solid dosage forms for oral use.
Cheung, Ka-Shing; Leung, Wai K
Novel oral anticoagulants (NOACs), which include direct thrombin inhibitor (dabigatran) and direct factor Xa inhibitors (rivaroxaban, apixaban and edoxaban), are gaining popularity in the prevention of embolic stroke in non-valvular atrial fibrillation as well as in the prevention and treatment of venous thromboembolism. However, similar to traditional anticoagulants, NOACs have the side effects of bleeding, including gastrointestinal bleeding (GIB). Results from both randomized clinical trials and observations studies suggest that high-dose dabigatran (150 mg b.i.d), rivaroxaban and high-dose edoxaban (60 mg daily) are associated with a higher risk of GIB compared with warfarin. Other risk factors of NOAC-related GIB include concomitant use of ulcerogenic agents, older age, renal impairment, Helicobacter pylori infection and a past history of GIB. Prevention of NOAC-related GIB includes proper patient selection, using a lower dose of certain NOACs and in patients with renal impairment, correction of modifiable risk factors, and prescription of gastroprotective agents. Overt GIB can be managed by withholding NOACs followed by delayed endoscopic treatment. In severe bleeding, additional measures include administration of activated charcoal, use of specific reversal agents such as idarucizumab for dabigatran and andexanent alfa for factor Xa inhibitors, and urgent endoscopic management. PMID:28373761
Patients undergoing surgery for total hip arthroplasty (THA) or total knee arthroplasty (TKA) are at particularly high risk for developing venous thromboembolism (VTE). Despite the existence of effective therapies for VTE prevention, THA/TKA patients remain at risk for developing thrombi. Furthermore, the incidence of VTE is predicted to increase as an aging and increasingly obese population experiences joint damage necessitating THA and TKA. Current guidelines recommend the use of a wide range of antithrombotic agents in patients undergoing THA and TKA. These agents include vitamin K antagonists, low-molecular-weight heparins, fondaparinux, and the new oral anticoagulants. However, adherence to guidelines in clinical practice is disappointingly low. The limitations of traditional anticoagulants present management challenges following orthopedic surgery. Vitamin K antagonists present a number of drawbacks, including a narrow therapeutic window and unpredictable pharmacokinetics and pharmacodynamics. The subcutaneous route of administration of fondaparinux and low-molecular-weight heparins may make them unacceptable to patients in the outpatient setting. The introduction of a new generation of anticoagulants promises to address many of the drawbacks associated with the traditional agents. Clinical studies have shown the new oral anticoagulants to be as effective as traditional thromboprophylaxis, with good tolerability profiles. Clinical knowledge of these new agents will be essential to ensure that patients receive appropriate care following orthopedic surgery. This article will discuss the prevention of VTE after THA and TKA based on current evidence-based practice guidelines, the limitations of conventional anticoagulants, and the promise of new therapeutics.
Hankey, Graeme J
This review article discusses the following, as yet unanswered, questions and research priorities to optimise patient management and stroke prevention in atrial fibrillation with the new direct oral anticoagulants (NOACs): 1. In patients prescribed a NOAC, can the anticoagulant effects or plasma concentrations of the NOACs be measured rapidly and reliably and, if so, can "cut-off points" between which anticoagulation is therapeutic (i.e. the "therapeutic range") be defined? 2. In patients who are taking a NOAC and bleeding (e.g. intracerebral haemorrhage), can the anticoagulant effects of the direct NOACs be reversed rapidly and, if so, can NOAC-associated bleeding and complications be minimised and patient outcome improved? 3. In patients taking a NOAC who experience an acute ischaemic stroke, to what degree of anticoagulation or plasma concentration of NOAC, if any, can thrombolysis be administered safely and effectively? 4. In patients with a recent cardioembolic ischaemic stroke, what is the optimal time to start (or re-start) anticoagulation with a NOAC (or warfarin)? 5. In anticoagulated patients who experience an intracranial haemorrhage, can anticoagulation with a NOAC be re-started safely and effectively, and if so when? 6. Are the NOACs effective and safe in multimorbid geriatric people (who commonly have atrial fibrillation and are at high risk of stroke but also bleeding)? 7. Can dose-adjusted NOAC therapy augment the established safety and efficacy of fixed-dose unmonitored NOAC therapy? 8. Is there a dose or dosing regimen for each NOAC that is as effective and safe as adjusted-dose warfarin for patients with atrial fibrillation who have mechanical prosthetic heart valves? 9. What is the long-term safety of the NOACs?
Debotton, Nir; Dahan, Arik
Over the last few decades, polymers have been extensively used as pharmaceutical excipients in drug delivery systems. Pharmaceutical polymers evolved from being simply used as gelatin shells comprising capsule to offering great formulation advantages including enabling controlled/slow release and specific targeting of drugs to the site(s) of action (the "magic bullets" concept), hence hold a significant clinical promise. Oral administration of solid dosage forms (e.g., tablets and capsules) is the most common and convenient route of drug administration. When formulating challenging molecules into solid oral dosage forms, polymeric pharmaceutical excipients permit masking undesired physicochemical properties of drugs and consequently, altering their pharmacokinetic profiles to improve the therapeutic effect. As a result, the number of synthetic and natural polymers available commercially as pharmaceutical excipients has increased dramatically, offering potential solutions to various difficulties. For instance, the different polymers may allow increased solubility, swellability, viscosity, biodegradability, advanced coatings, pH dependency, mucodhesion, and inhibition of crystallization. The aim of this article is to provide a wide angle prospect of the different uses of pharmaceutical polymers in solid oral dosage forms. The various types of polymeric excipients are presented, and their distinctive role in oral drug delivery is emphasized. The comprehensive know-how provided in this article may allow scientists to use these polymeric excipients rationally, to fully exploit their different features and potential influence on drug delivery, with the overall aim of making better drug products.
Nakashima, Megan O.
Hypercoagulability can result from a variety of inherited and, more commonly, acquired conditions. Testing for the underlying cause of thrombosis in a patient is complicated both by the number and variety of clinical conditions that can cause hypercoagulability as well as the many potential assay interferences. Using an algorithmic approach to hypercoagulability testing provides the ability to tailor assay selection to the clinical scenario. It also reduces the number of unnecessary tests performed, saving cost and time, and preventing potential false results. New oral anticoagulants are powerful tools for managing hypercoagulable patients; however, their use introduces new challenges in terms of test interpretation and therapeutic monitoring. The coagulation laboratory plays an essential role in testing for and treating hypercoagulable states. The input of laboratory professionals is necessary to guide appropriate testing and synthesize interpretation of results. PMID:25025009
Hohnloser, S H
Non-vitamin K oral anticoagulants (NOAC) have now become established for stroke prevention in atrial fibrillation. The efficacy is at least as good if not better than that of vitamin K antagonists (VKA). The risk for major bleeding is less for NOAC than for VKA, with a particular superiority concerning the avoidance of intracerebral hemorrhage. The outcome after major bleeding is more favorable in patients receiving NOAC compared to those treated with VKA. Specific reversal agents for NOAC are currently being tested which neutralize the effects of NOAC within minutes and the clinical introduction of the first one for the thrombin inhibitor dabigatran is imminent. Such specific antidotes will further improve the safety profile of NAOC.
Mar, Philip L; Familtsev, Dmitry; Ezekowitz, Michael D; Lakkireddy, Dhanunjaya; Gopinathannair, Rakesh
An increasing number of individuals are on novel oral anticoagulants (NOAC) for anticoagulation instead of vitamin K antagonists (VKA) and roughly 10% of these individuals will require interruption of these agents for procedures annually. Recent evidence surrounding bridging as well as the FDA approval of a new NOAC call for a comprehensive review and update regarding periprocedural NOAC management. The periprocedural management of NOACs involves striking a balance between the risks of bleeding and thromboembolism associated with interruption, bridging, and reinitiation of anticoagulation. NOACs have a distinct pharmacokinetic advantage in this setting with their quick onset and elimination from the body. Procedures at low risk for bleeding do not require interruption and can be scheduled at the start of the next dosing interval. Procedures at moderate-high risk of bleeding require interruption of NOAC for 5 half lives prior to the procedure to allow for adequate elimination of the drug. In light of new evidence highlighting the risks of bleeding, and given shorter "unprotected" times with NOAC interruption versus VKA, patients at low-moderate risk for thromboembolism should not be bridged when "unprotected" time is less than 96 h. For patients at high risk for thromboembolism, individual patient and surgical factors need to be considered before the decision to bridge is made. The benefit of bridging these patients who have a considerable risk of bleeding may not outweigh the benefits. Focused randomized studies on periprocedural management of NOACs are urgently needed.
Yang, Yea-Huei Kao; Lu, Christine Y.
Background This study quantitatively evaluated the comparative efficacy and safety of new oral anticoagulants (dabigatran, rivaroxaban, and apizaban) and warfarin for treatment of nonvalvular atrial fibrillation. We also compared these agents under different scenarios, including population with high risk of stroke and for primary vs. secondary stroke prevention. Methods We used multiple criteria decision analysis (MCDA) to assess the benefit-risk of these medications. Our MCDA models contained criteria for benefits (prevention of ischemic stroke and systemic embolism) and risks (intracranial and extracranial bleeding). We calculated a performance score for each drug accounting for benefits and risks in comparison to treatment alternatives. Results Overall, new agents had higher performance scores than warfarin; in order of performance scores: dabigatran 150 mg (0.529), rivaroxaban (0.462), apixaban (0.426), and warfarin (0.191). For patients at a higher risk of stroke (CHADS2 score≥3), apixaban had the highest performance score (0.686); performance scores for other drugs were 0.462 for dabigatran 150 mg, 0.392 for dabigatran 110 mg, 0.271 for rivaroxaban, and 0.116 for warfarin. Dabigatran 150 mg had the highest performance score for primary stroke prevention, while dabigatran 110 mg had the highest performance score for secondary prevention. Conclusions Our results suggest that new oral anticoagulants might be preferred over warfarin. Selecting appropriate medicines according to the patient’s condition based on information from an integrated benefit-risk assessment of treatment options is crucial to achieve optimal clinical outcomes. PMID:25897861
Olivera, M E; Manzo, R H; Junginger, H E; Midha, K K; Shah, V P; Stavchansky, S; Dressman, J B; Barends, D M
Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of new multisource and reformulated immediate release (IR) solid oral dosage forms containing ciprofloxacin hydrochloride as the only active pharmaceutical ingredient (API) are reviewed. Ciprofloxacin hydrochloride's solubility and permeability, its therapeutic use and index, pharmacokinetics, excipient interactions and reported BE/bioavailability (BA) problems were taken into consideration. Solubility and BA data indicate that ciprofloxacin hydrochloride is a BCS Class IV drug. Therefore, a biowaiver based approval of ciprofloxacin hydrochloride containing IR solid oral dosage forms cannot be recommended for either new multisource drug products or for major scale-up and postapproval changes (variations) to existing drug products.
Ezekowitz, Michael D; Spahr, Judy; Ghosh, Pradeepto; Corelli, Kathryn
Anticoagulation for stroke prevention in atrial fibrillation (AF) is effective. Pivotal trials RE-LY, ROCKET AF, ARISTOTLE, and ENGAGE-AF TIMI 48 tested novel agents against warfarin (W). In RE-LY, an open-label trial, dabigatran 150 mg BID (D150) was superior (35%) and 110 mg BID (D110) was noninferior to W. D150 reduced ischemic strokes by 25% and intracerebral bleeds by 74%, but increased major GI bleeds by 0.5 % per year. In ROCKET AF, a double-blind study, rivaroxaban 20 mg daily, downtitrated to 15 mg daily (if CrCl was <49) was noninferior for efficacy and safety, with an increase in GI bleeds. In ARISTOTLE, a double-blind study, apixaban 5 mg BID (downtitrated to 2.5 mg BID if two of the following were present: age, >80; weight, <60 kg; or serum creatinine, >1.5 mg) was superior for safety (31%), efficacy (21%), and all-cause mortality (11%). In ENGAGE-AF TIMI 48, edoxaban 60 mg once daily (30 mg once daily if CrCl 30-50 ml/min, weight <60 kg, or concomitant verapamil or quinidine) was noninferior to W for efficacy, but reduced major bleeding (20%). To translate clinical trials to practice, understanding the disease and each anticoagulant is essential. For all novel agents, rapid anticoagulation, absence of monitoring, and a short half-life differentiate them from W. Bleed rates were either noninferior or lower than for W, without an antidote. Patient compliance is critical. Knowledge of renal function is essential and maintaining patients on therapy is key.
Guarascio, Anthony J; Slain, Douglas
The triazole antifungal posaconazole was first approved as an oral suspension formulation. Despite pharmacokinetic target attainment and clinical efficacy in premarketing trials, postmarketing analyses indicated unpredictable bioavailability resulting in subtherapeutic concentrations and reports of breakthrough fungal infections. The newly approved posaconazole delayed-release tablet and intravenous formulations display more consistent bioavailability in the presence of concomitant disease states, medications, and dietary considerations that classically alter drug concentrations of the oral suspension. Both the delayed-release tablet and intravenous formulation display a similar adverse-effect profile to the oral suspension. The posaconazole delayed-release oral tablet is not significantly affected by gastric acid suppression therapy, and the intravenous dosage form provides an option for patients who are intubated or unable to tolerate oral medications. Pharmacoeconomic considerations, particularly with intravenous posaconazole, will likely play a role in dosage form selection and frequency of use. Due to sustained, higher drug concentrations, the new posaconazole formulations hold promise for greater efficacy in antifungal prophylaxis and bring opportunity for further study in the treatment of invasive mycoses.
Becker, C; Dressman, J B; Amidon, G L; Junginger, H E; Kopp, S; Midha, K K; Shah, V P; Stavchansky, S; Barends, D M
Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing ethambutol dihydrochloride as the only active pharmaceutical ingredient (API) are reviewed. Ethambutol dihydrochloride is a Biopharmaceutics Classification System (BCS) Class III drug with permeability properties approaching the border between BCS Class I and III. BE problems of ethambutol formulations containing different excipients and different dosages forms have not been reported and hence the risk of bioinequivalence caused by excipients is low. Ethambutol has a narrow therapeutic index related to ocular toxicity. However, as long as the prescribers' information of the test product stipulates the need for regular monitoring of ocular toxicity, the additional patient risk is deemed acceptable. It is concluded that a biowaiver can be recommended for IR solid oral dosage forms provided that the test product (a) contains only excipients present in ethambutol IR solid oral drug products approved in ICH or associated countries, for instance as presented in this paper, (b) complies with the criteria for "very rapidly dissolving" and (c) has a prescribers' information indicating the need for testing the patient's vision prior to initiating ethambutol therapy and regularly during therapy.
Kim, Ji-young; Jeon, Ok-Cheol; Moon, Hyun Tae; Hwang, Seung Rim; Byun, Youngro
The preclinical safety of a newly developed oral anticoagulant, the low molecular weight heparin-deoxycholate conjugate (OH09208), was evaluated by a comprehensive evaluating program in compliance with standard guidelines. The single dose oral toxicity study in rats receiving 2000 and 5000 mg kg(-1) of OH09208 did not reveal any mortality, unusual body weight changes or necropsy findings. The results of the 4-week oral toxicity study with a 4-week recovery program in rats receiving OH09208 in doses of 100, 300 and 1000 mg kg(-1) day(-1) did not reveal any mortality, or indicate any unusual clinical signs, or show any toxicokinetic relationships to the administration of OH09208. Although the increase in liver enzymes in one male dog treated with 300 mg kg(-1) day(-1) and one female dog treated with 1000 mg kg(-1) day(-1) could not be excluded from the effect of the test substance, no other toxicologically significant changes were observed in the 4-week oral toxicity study with a 4-week recovery in beagle dogs. Thus, while the no-observed-adverse-effect level value from the 4-week study in both male and female rats was 1000 mg kg(-1) day(-1), those from the 4-week study in male and female beagle dogs were 300 and 1000 mg kg(-1) day(-1), respectively. Furthermore, OH09208 did not induce anaphylactic reactions in guinea pigs, micronucleated bone marrow cells in male ICR mice, chromosomal aberration in Chinese hamster lung cell lines, bacterial reverse mutation, and any abnormalities in hERG current assay, mouse central nervous system and dog cardiovascular studies. Overall, there were no unexpected toxicities in this preclinical study that might have precluded the safe administration of OH09208 to humans.
Objectives The first non-vitamin K antagonist oral anticoagulant (NOAC) introduced to the market in Japan was dabigatran in March 2011, and three more NOACs, rivaroxaban, apixaban, and edoxaban, have since become available. Randomized controlled trials of NOACs have revealed that intracranial hemorrhage (ICH) occurs less frequently with NOACs compared with warfarin. However, the absolute incidence of ICH associated with NOACs has increased with greater use of these anticoagulants, and we wanted to explore the incidence, clinical characteristics, and treatment course of patients with NOACs-associated ICH. Methods We retrospectively analyzed the characteristics of symptomatic ICH patients receiving NOACs between March 2011 and September 2014. Results ICH occurred in 6 patients (5 men, 1 woman; mean ± SD age, 72.8 ± 3.2 years). Mean time to onset was 146.2 ± 111.5 days after starting NOACs. Five patients received rivaroxaban and 1 patient received apixaban. None received dabigatran or edoxaban. Notably, no hematoma expansion was observed within 24 h of onset in the absence of infusion of fresh frozen plasma, activated prothrombin complex concentrate, recombinant activated factor VIIa or hemodialysis. When NOAC therapy was initiated, mean HAS-BLED and PANWARDS scores were 1.5 ± 0.5 and 39.5 ± 7.7, respectively. Mean systolic blood pressure was 137.8 ± 15.9 mmHg within 1 month before spontaneous ICH onset. Conclusion Six symptomatic ICHs occurred early in NOAC therapy but hematoma volume was small and did not expand in the absence of infusion of reversal agents or hemodialysis. The occurrence of ICH during NOAC therapy is possible even when there is acceptable mean systolic blood pressure control (137.8 ± 15.9 mmHg) and HAS-BLED score ≤ 2. Even stricter blood pressure lowering and control within the acceptable range may be advisable to prevent ICH during NOAC therapy. PMID:26171862
Beyer-Westendorf, Jan; Michalski, Franziska; Tittl, Luise; Middeldorp, Saskia; Cohen, Hannah; Abdul Kadir, Rezan; Arachchillage, Deepa Jayakody; Arya, Roopen; Ay, Cihan; Marten, Sandra
Today, direct oral anticoagulants (DOAC) are widely used alternatives to Vitamin-K antagonists (VKA). Women of reproductive age may become pregnant during anticoagulation and, while VKA carry an embryotoxic potential, the risk of DOAC embryopathy is unknown. As a result, some patients elect to terminate pregnancy for fear of DOAC embryotoxicity. To assess the risk of DOAC embryopathy, we reviewed cases of DOAC exposure in pregnancy collected from physicians, literature and pharmacovigilance systems of drug authorities and manufacturers. A total of 357 reports including duplicates were available from which 233 unique cases could be identified. Information on pregnancy outcome was available in only 137/233 cases (58.8 %): 67 live births (48.9 %); 31 miscarriages (22.6 %); 39 elective pregnancy terminations (28.5 %). In 93 cases (39.9 %) no outcome data were available (including 3 cases of ongoing pregnancy). Of the 137 pregnancies with reported outcomes, seven showed abnormalities (5.1 %) of which three (2.2 %) could potentially be interpreted as embryopathy: live birth with facial dysmorphism; miscarriage in week 10 with limb abnormality; elective pregnancy termination due to a foetal cardiac defect in a woman who had to terminate a previous pregnancy due to Fallot tetralogy. Within its limitations (small numbers, incomplete outcome data) our results do not indicate that DOAC exposure in pregnancy carries a high risk of embryopathy or that DOAC exposure per se should be used to direct patient counselling towards pregnancy termination. Pregnancy outcome data are inconsistently captured in pharmacovigilance databases indicating the strong need for a more robust system of reporting.
Raimondi, Peter; Hylek, Elaine M; Aronis, Konstantinos N
There is an increasing prevalence of cardiovascular diseases that warrant antithrombotic therapy. Antithrombotic therapy includes antiplatelet agents and anticoagulation therapy with vitamin K antagonists (VKAs) or non-Vitamin K oral anticoagulants (NOACs). Antithrombotic therapy is associated with increased rates of bleeding. In this review we summarize the evidence and provide strategies for the management of severe bleeding in the setting of antithrombotic therapy. There is limited data on the management of bleeding in the setting of antiplatelet therapy. We recommend discontinuation of the antiplatelet, as well as administration of platelet transfusions and desmopressin only in the setting of life-threatening bleeding. For patients presenting with severe bleeding in the setting of VKAs, we recommend discontinuation of VKA and prompt administration of 10 mg intravenous vitamin K plus 50 units/kg 4-factor prothrombin complex concentrate (PCC). If 4-factor PCC is not available 3-factor PCC or fresh frozen plasma (FFP) can be used, but these are inferior to 4-factor PCC. For patients presenting with severe bleeding while on dabigatran, we recommend discontinuation of dabigatran and intravenous administration of 5g idarucizumab. There is currently no available reversal agent for factor Xa inhibitors. Andexanet alpha is a factor Xa-specific inhibitor that is currently undergoing FDA review. Until andexanet alpha becomes available we recommend discontinuation of the factor Xa inhibitor and administration of 50 units/kg 4-factor PCC. The decision to discontinue and/or reverse antithrombotic therapy should be made on a case-by-case basis and the competing risk from discontinuation and/or reversal of antithrombotic therapy should be taken in consideration.
Whalley, D; Skappak, C; Lang, E S
The new factor Xa inhibitors and direct thrombin inhibitors have offered alternatives to traditional anticoagulants, with benefits of no routine monitoring, less drug interactions, and oral administration. Current approved uses of these agents include prophylaxis of stroke in non-valvular atrial fibrillation and prevention of venous thromboembolism (VTE) following hip and knee arthroplasty. However, concern over bleeding risk in the context of having no specific antidotes available is a topic of focus for many physicians in an acute care setting. This manuscript examines the recent literature in the management of acute bleeding and the various methods of reversing anticoagulation in this setting. Literature published over the last 18 months (2011/07/01-present) was gathered from PubMed, Ovid, and Medline under a combined search strategy covering bleeding, reversal, and new oral anticoagulants, both factor Xa and direct thrombin inhibitors. The use of prothrombin complex concentrate, fresh frozen plasma, activated recombinant factor VII, activated prothrombin complex concentrate, as well as adjuncts of charcoal, hemodialysis, and antifibrinolytics are discussed. Recommendations are based on the determination of the severity of the bleed and physiological markers of anticoagulation, and involve the use of prothrombin complex concentrate, activated recombinant factor VII, and adjunctive therapy as appropriate.
Chen, Ang; Shi, Ye; Yan, Zhiqiang; Hao, Hongxun; Zhang, Yong; Zhong, Jian; Hou, Huiming
A large amount of new drug candidates are practically insoluble in aqueous solvents and are even simultaneously poorly soluble in organic solvents. Nanosuspension drug delivery system (DDS) was firstly developed in 1994 and has attracted more and more attention as a formation solution for the poorly soluble drugs. By nansizing the poorly soluble drugs, nanosuspensions have several outstanding advantages for drug delivery. Among many administration routes of drug delivery, oral administration is the most preferred route due to its advantages such as ease of ingestion, versatility to accommodate various types of drug candidates, low production cost, high safety, good patient compliance, and pain avoidance. Current marketed pharmaceutical nanosuspension DDS products are mostly for oral administration. This review is to systematically summarize the nanosuspension DDS dosage form developments of poorly soluble drugs for oral administration use.
Charoo, Naseem; Cristofoletti, Rodrigo; Graham, Alexandra; Lartey, Paul; Abrahamsson, Bertil; Groot, D W; Kopp, Sabine; Langguth, Peter; Polli, James; Shah, Vinod P; Dressman, Jennifer
Literature data pertaining to the decision to allow a waiver of in vivo bioequivalence (BE) testing requirements for the approval of immediate release (IR) solid oral dosage forms containing fluconazole as the only active pharmaceutical ingredient (API) are reviewed. The decision is based on solubility, dissolution, permeability, therapeutic index, pharmacokinetic parameters, pharmacodynamic properties, and other relevant data. BE/bioavailability (BA) problems and drug-excipients interaction data were also reviewed and taken into consideration. According to the biopharmaceutics classification system (BCS), fluconazole in polymorphic forms II and III is a BCS class I drug and has a wide therapeutic index. BE of test formulations from many different manufacturers containing different excipients confirmed that the risk of bioinequivalence because of formulation and manufacturing factors is low. It was inferred that risk can be further reduced if in vitro studies are performed according to biowaiver guidelines. Thus, it is concluded that a biowaiver can be recommended for fluconazole IR dosage forms if (a) fluconazole is present as polymorphic form II or III or any other form/mixture showing high solubility, (b) the selection of excipients be limited to those found in IR drug products approved in International Conference on Harmonisation (ICH) countries for the same dosage form and used in their usual amounts, and (c) both the test and comparator dosage form are very rapidly dissolving, or, rapidly dissolving throughout the shelf life with similar dissolution profiles at pH 1.2, 4.5, and 6.8.
Silva, Arthur L L; Cristofoletti, Rodrigo; Storpirtis, Silvia; Sousa, Varley D; Junginger, Hans E; Shah, Vinod P; Stavchansky, Salomon; Dressman, Jennifer B; Barends, Dirk M
Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate-release (IR) solid oral dosage forms containing stavudine (d4T) are reviewed. According to Biopharmaceutics Classification System (BCS), d4T can be assigned to BCS class I. No problems with BE of IR d4T formulations containing different excipients and produced by different manufacturing methods have been reported and, hence, the risk of bioinequivalence caused by these factors appears to be low. Furthermore, d4T has a wide therapeutic index. It is concluded that a biowaiver is appropriate for IR solid oral dosage forms containing d4T as the single active pharmaceutical ingredient (API) provided that (a) the test product contains only excipients present in the IR d4T drug products that have been approved in a number of countries for the same dosage form, and (b) both test product and its comparator are either "very rapidly dissolving" or "rapidly dissolving" with similarity of dissolution profiles demonstrated at pH 1.2, 4.5, and 6.8.
Wening, Klaus; Laukamp, Eva Julia; Thommes, Markus; Breitkreutz, Jörg
New devices enabling freely selectable dosing of solid oral medications are urgently needed for personalized medicine. One approach is the use of the recently published Solid Dosage Pen, allowing flexible dosing of tablet-like sustained release slices from drug loaded extruded strands. Slices were suitable for oral single dosed application. The aim of the present study was the development of immediate release dosage forms for applications of the device, especially for young children. Using two model drugs, two different concepts were investigated and evaluated. Effervescent formulations were manufactured by an organic wet-extrusion process and immediate release formulations by a melt-extrusion process. Dissolution experiments were performed for both formulations to ensure the immediate release behavior. Extruded strands were individually dosed by the Solid Dosage Pen. Various doses of the two formulations were analyzed regarding uniformity of mass and content according to pharmacopoeial specifications. Proof of concept was demonstrated in both approaches as results comply with the regulatory requirements. Furthermore, storing stress tests were performed and drug formulations were characterized after storing. The results show that suitable packaging material has been selected and storage stability is probable. PMID:25562361
Grube, S; Langguth, P; Junginger, H E; Kopp, S; Midha, K K; Shah, V P; Stavchansky, S; Dressman, J B; Barends, D M
Literature data are reviewed relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of new multisource and reformulated immediate release (IR) solid oral dosage forms containing quinidine sulfate. Quinidine sulfate's solubility and permeability, its therapeutic use and index, pharmacokinetics, excipient interactions and reported BE/bioavailability (BA) problems were taken into consideration. The available data are not fully conclusive, but do suggest that quinidine sulfate is highly soluble and moderately to highly permeable and would likely be assigned to BCS Class I (or at worst BCS III). In view of the inconclusiveness of the data and, more important, quinidine's narrow therapeutic window and critical indication, a biowaiver based approval of quinidine containing dosage forms cannot be recommended for either new multisource drug products or for major postapproval changes (variations) to existing drug products.
Gajendran, Jayachandar; Krämer, Johannes; Shah, Vinod P; Langguth, Peter; Polli, James; Mehta, Mehul; Groot, D W; Cristofoletti, Rodrigo; Abrahamsson, Bertil; Dressman, Jennifer B
Literature data relevant to the biopharmaceutical properties of the active pharmaceutical ingredient (API) nifedipine are reviewed to evaluate whether a waiver of in vivo bioequivalence (BE) testing of immediate-release (IR) dosage forms formulated as tablets and soft gelatin capsules is warranted. Nifedipine's solubility and permeability, its therapeutic use and index, pharmacokinetics, food drug interactions, and any reported BE/bioavailability problems were all taken into consideration. Solubility and BA data indicate conclusively that nifedipine is a class II substance of biopharmaceutics classification system (BCS) and that the formulation of drug product plays a key role on the dissolution characteristics of the API. Therefore, a BCS biowaiver-based approval of nifedipine containing IR oral dosage forms cannot be recommended for reformulated/new multisource drug products or for major scale-up and postapproval changes to the existing drug products.
Jantratid, E; Strauch, S; Becker, C; Dressman, J B; Amidon, G L; Junginger, H E; Kopp, S; Midha, K K; Shah, V P; Stavchansky, S; Barends, D M
Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing doxycycline hyclate are reviewed. According to the Biopharmaceutics Classification System (BCS), doxycycline hyclate can be assigned to BCS Class I. No problems with BE of IR doxycycline formulations containing different excipients and produced by different manufacturing methods have been reported and hence the risk of bioinequivalence caused by these factors appears to be low. Doxycycline has a wide therapeutic index. Further, BCS-based dissolution methods have been shown to be capable of identifying formulations which may dissolve too slowly to generate therapeutic levels. It is concluded that a biowaiver is appropriate for IR solid oral dosage forms containing doxycycline hyclate as the single Active Pharmaceutical Ingredient (API) provided that (a) the test product contains only excipients present in doxycycline hyclate IR solid oral drug products approved in the International Conference on Harmonization (ICH) or associated countries; and (b) the comparator and the test products comply with the BCS criteria for "very rapidly dissolving" or, alternatively, when similarity of the dissolution profiles can be demonstrated and the two products are "rapidly dissolving.".
Owens, Ryan E; Kabra, Rajesh; Oliphant, Carrie S
Direct oral anticoagulants (DOACs) are indicated for stroke prevention in patients with nonvalvular atrial fibrillation (NVAF), which, according to the American College of Cardiology/American Heart Association/Heart Rhythm Society atrial fibrillation (AF) guidelines, excludes patients with rheumatic mitral stenosis, a mechanical or bioprosthetic heart valve, or mitral valve repair. However, the data regarding use of DOACs in AF patients with other types of valvular heart disease (VHD) are unclear. We aimed to summarize and evaluate the literature regarding the safety and efficacy of DOAC use in NVAF patients with other types of VHD. After an extensive literature search, a total of 1 prospective controlled trial, 4 subanalyses, and 1 abstract were identified. Efficacy of the DOAC agents in NVAF patients with VHD mirrored the overall trial results. Bleeding risk was significantly increased in VHD patients treated with rivaroxaban, but not for dabigatran or apixaban. Of the bioprosthetic valve patients enrolled in the Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation (ARISTOTLE) trial, no safety or efficacy concerns were identified. In conclusion, subanalyses of DOAC landmark AF trials revealed that dabigatran, rivaroxaban, and apixaban may be safely used in AF patients with certain types of VHD: aortic stenosis, aortic regurgitation, and mitral regurgitation. More evidence is needed before routinely recommending these agents for patients with bioprosthetic valves or mild mitral stenosis. Patients with moderate to severe mitral stenosis or mechanical valves should continue to receive warfarin, as these patients were excluded from all landmark AF trials.
Direct oral anticoagulant (DOAC) drugs (dabigatran, rivaroxaban, and apixaban) have emerged in the last decade to overcome some of the drawbacks of existing medications. To date, little is known about the dental management of patients taking these drugs. This study was undertaken to establish the evidence for the management of patients undergoing dental procedures while taking these medications. A rapid review approach was used to identify clinical and scientific research related to dental surgery performed in patients taking DOACs in order to produce an evidence summary. The rapid review did not identify any systematic reviews or original clinical trials and the overall quality of evidence found was poor. Most of the literature consisted of non-structured review articles and guidance documents based on assumptions from non-dental data and expert opinion, and recommendations on best practice varied throughout. The findings from the review of the literature varied considerably. Currently, recommendations are based on poor quality scientific data and clinical trials are required to establish best evidence-based practice guidance.
Rodríguez-Reyes, Humberto; Arauz-Góngora, Antonio; Asensio-Lafuente, Enrique; Celaya-Cota, Manuel de Jesús; Cordero-Cabra, Alejandro; Guevara-Valdivia, Milton; Izaguirre-Avila, Raúl; Lara-Vaca, Susano; Mariona-Moreno, Vitelio; Martínez-Flores, Enrique; Nava-Townsend, Santiago; Pozas-Garza, Gerardo; Rodríguez-Diez, Gerardo
Knowing the real impact of atrial fibrillation in the stroke, the Sociedad Mexicana of Electrofisiología y Estimulación Cardiaca (SOMEEC) had the initiative to develop a multidisciplinary meeting of experts the with the purpose to update the available scientific evidence from clinical practice guidelines, meta-analyses, controlled clinical trials, and complementing with the experience and views of a group of experts. To meet this goal, SOMEEC gathered a group of specialists in the area of cardiology, electrophysiology, neurology and hematology that given their experience in certain areas, they share the scientific evidence with the panel of experts to leave open a discussion about the information presented in this article. This document brings together the best scientific evidence available and aims to be a useful tool in the decision to use of new oral anticoagulants in nonvalvular atrial fibrillation and ischemic heart disease, or relating to the management of patients with stroke or renal failure, and even those that will be submitted to elective surgery and invasive procedures. In the same, they handled comparative schemes of follow-up and treatment which simplifies the decision making by the specialists participants.
The nonvitamin K antagonist oral anticoagulants (NOACs) dabigatran, rivaroxaban, apixaban, and edoxaban are associated with an equal or lower incidence of stroke and systemic embolism and a much lower incidence of intracranial hemorrhage and hemorrhagic stroke than warfarin is, without the need for routine laboratory monitoring. However, reversal strategies are not currently established in the case of NOAC-related hemorrhagic stroke. In emergency situations, well-defined management for NOAC-related hemorrhagic stroke may improve clinical outcomes. Thus, in this chapter, general measures initially required to prevent the expansion of intracerebral hematomas, charcoal administration to reduce NOAC absorption from the gastrointestinal tract, application of hemodialysis to remove dabigatran, and coagulation factor therapy including 4-factor prothrombin complex concentrate and recombinant activated factor VII are reviewed. The specific reversal agents idarucizumab, which is a monoclonal antibody against dabigatran; andexanet alfa, a recombinant human factor Xa decoy for Xa inhibitors; and PER977, a small synthetic molecule for reversal of both Xa and thrombin inhibitors, are currently under development. These agents will facilitate the clinical management of NOAC-associated hemorrhagic stroke and other severe bleeding.
Bertoletti, Laurent; Ollier, Edouard; Duvillard, Cécile; Delavenne, Xavier; Beyens, Marie-Noëlle; De Magalhaes, Elodie; Bellet, Florelle; Basset, Thierry; Mismetti, Patrick; Laporte, Silvy
The treatment of acute venous thromboembolism (VTE) is being completely modified with the development of direct oral anticoagulants (DOACs). Rivaroxaban, apixaban and edoxaban directly inhibit factor Xa, whereas dabigatran inhibits factor IIa. All these drugs are proposed orally, and share pharmacological similarities: fixed doses without any therapeutic drug monitoring, key role of the transporter proteins P-glycoprotein for all of them and metabolism mediated by CYP3A4 for the anti-Xa, short half-life with variable rate of renal elimination. More than 25 000 patients with acute VTE were included in phase-III studies. Rivaroxaban and apixaban challenged all the conventional therapy (parenteral heparins followed by anti-vitamin K antagonists) whereas edoxaban and dabigatran challenged only anti-vitamin K antagonists. All the DOACs met the non-inferiority efficacy endpoint (recurrent VTE during treatment), whereas the large non-inferiority margin was debated for dabigatran. However, they were associated with better safety and a decreased risk of major bleeding. According to indirect comparisons, there were no statistically significant differences between DOACs in terms of efficacy but some differences are not excluded in term of safety. Although DOACs allow for simplification of treatment in the majority of patients with acute VTE, their risk/benefit ratio is questioned in elderly patients, patients with mild-to-severe renal impairment, and in some clinical subgroups such as cancer or chronic thromboembolic pulmonary hypertension. Validated reversal strategies (potentially based on laboratory monitoring) are expected for patients with major bleeding, overdose or with a need for surgery.
Stanisz, Beata J; Paszun, Sylwia K; Zalewska, Anna
Abstract: Cilazapril is a drug commonly used in management of heart failure in pediatric population. On pharmaceutical market it is available only in inconvenient for pediatric use tablet dosage forms. Until now, no oral liquid formulation containing cilazapril has been evaluated. Therefore, the aim of this study was to prepare easy to made and palatable 1 mg/mL oral liquid formulation with cilazapril (with consideration of original and generic cilazapril tablet and different packages) and subsequent investigation of physicochemical stability of these suspensions. Formulations were compounded using cilazapril obtained from original or generic cilazapril marketed tablet formulations and Ora-Blend" suspending agent. Stability of prepared suspensions stored in closed amber glass or amber plastic PET bottles in the temperature of 298 K was estimated throughout 28 day shelf-life period. Chemical stability was assessed by HPLC cilazapril stability indicating method. Physical stability was evaluated by appearance, taste, smell, pH and theological assessments. Cilazapril oral suspensions at concentration of 1 mg/mL demonstrated satisfactory stability over 28 day long storage at room temperature. Cilazapril concentrations remained within acceptable limit (+/- 10%) stored in closed amber bottles made of glass or PET material. Moreover, suspensions physical properties remained unaffected. Cilazapril - Ora-Blend* pediatric oral liquid is easy to made, palatable and stable when stored at room temperature for 28 days. Stability of cilazapril oral liquid remains unchanged while using cilazapril tablets produced by different manufacturers and bottles made of amber glass or PET material.
Tompson, Alice; Heneghan, Carl; Sutton, Stephen; Fitzmaurice, David; Ward, Alison
Objective To explore the impact self-funding has on patient experience of oral anticoagulation therapy self-monitoring. Design Semistructured, qualitative interviews were conducted. Transcripts were analysed thematically using constant comparison. Setting England. Participants Interviewees were participants of the Cohort Study of Anticoagulation Self-Monitoring (CASM). Cohort members were recruited as they bought a monitor from the major manufacturer in the UK. A purposive sample was invited to be interviewed on completion of the 12-month cohort follow-up. Data Patient narratives on their experiences of self-monitoring their oral anticoagulation therapy in non-trial conditions. Results 26 interviews were completed. Interviewees viewed purchasing the monitoring device as a long-term commitment balancing the limitations of clinic-based monitoring against the cost. They were unable to try out the monitor prior to purchase and therefore had to be confident in their own ability to use it. The variable provision of self-monitoring equipment caused resentment, and interviewees were uncomfortable negotiating with healthcare professionals. High test strip usage while learning how to use the monitor caused anxiety that was exacerbated by worries about their cost. However, self-funding did mean that interviewees felt a sense of ownership and were determined to persevere to overcome problems. Conclusions Self-funding has negative implications in terms of equity of access; however, the money invested acts as a barrier to discontinuation. If oral anticoagulation therapy self-monitoring devices and consumables were provided free of charge in routine care, the training and support available in England may need to be reviewed to prevent discontinuation rates rising to those observed in clinical trials. PMID:28011812
... HUMAN SERVICES Food and Drug Administration Guidance for Industry on Dosage Delivery Devices for Orally.... SUMMARY: The Food and Drug Administration (FDA) is announcing the availability of a guidance for industry... intended to provide guidance to firms that are manufacturing, marketing, or distributing orally...
Chuasuwan, B; Binjesoh, V; Polli, J E; Zhang, H; Amidon, G L; Junginger, H E; Midha, K K; Shah, V P; Stavchansky, S; Dressman, J B; Barends, D M
Literature data are reviewed regarding the scientific advisability of allowing a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing either diclofenac potassium and diclofenac sodium. Within the biopharmaceutics classification system (BCS), diclofenac potassium and diclofenac sodium are each BCS class II active pharmaceutical ingredients (APIs). However, a biowaiver can be recommended for IR drug products of each salt form, due to their therapeutic use, therapeutic index, pharmacokinetic properties, potential for excipient interactions, and performance in reported BE/bioavailability (BA) studies, provided: (a) test and comparator contain the same diclofenac salt; (b) the dosage form of the test and comparator is identical; (c) the test product contains only excipients present in diclofenac drug products approved in ICH or associated countries in the same dosage form, for instance as presented in this paper; (d) test drug product and comparator dissolve 85% in 30 min or less in 900 mL buffer pH 6.8, using the paddle apparatus at 75 rpm or the basket apparatus at 100 rpm; and (e) test product and comparator show dissolution profile similarity in pH 1.2, 4.5, and 6.8.
Vyas, Nimish B.; Rattner, Barnett A.
Avian risk assessments for rodenticides are often driven by the results of standardized acute oral toxicity tests without regards to a toxicant's mode of action and time course of adverse effects. First generation anticoagulant rodenticides (FGARs) generally require multiple feedings over several days to achieve a threshold concentration in tissue and cause adverse effects. This exposure regimen is much different than that used in the standardized acute oral toxicity test methodology. Median lethal dose values derived from standardized acute oral toxicity tests underestimate the environmental hazard and risk of FGARs. Caution is warranted when FGAR toxicity, physiological effects, and pharmacokinetics derived from standardized acute oral toxicity testing are used for forensic confirmation of the cause of death in avian mortality incidents and when characterizing FGARs' risks to free-ranging birds.
Weitschies, Werner; Blume, Henning; Mönnikes, Hubert
Knowledge about the performance of dosage forms in the gastrointestinal tract is essential for the development of new oral delivery systems, as well as for the choice of the optimal formulation technology. Magnetic Marker Monitoring (MMM) is an imaging technology for the investigation of the behaviour of solid oral dosage forms within the gastrointestinal tract, which is based on the labelling of solid dosage forms as a magnetic dipole and determination of the location, orientation and strength of the dipole after oral administration using measurement equipment and localization methods that are established in biomagnetism. MMM enables the investigation of the performance of solid dosage forms in the gastrointestinal tract with a temporal resolution in the range of a few milliseconds and a spatial resolution in 3D in the range of some millimetres. Thereby, MMM provides real-time tracking of dosage forms in the gastrointestinal tract. MMM is also suitable for the determination of dosage form disintegration and for quantitative measurement of in vivo drug release in case of appropriate extended release dosage forms like hydrogel-forming matrix tablets. The combination of MMM with pharmacokinetic measurements (pharmacomagnetography) enables the determination of in vitro-in vivo correlations (IVIC) and the delineation of absorption sites in the gastrointestinal tract.
Ahmed, Zaheer; Hassan, Seemeen; Salzman, Gary A.
Warfarin was the only oral anticoagulant available for the treatment of venous thromboembolism for about half a century until the recent approval of novel oral agents dabigatran, rivoraxaban and apixaban. This presents new classes of medications less cumbersome to use. They do not require frequent laboratory monitoring or have nurmerous drug interactions. On the other hand it also poses a challenge to the physicians deciding which agent to use in specific patient populations, how to predict the bleeding risk compared to warfarin and between the different novel agents and how to manage bleeding with relatively recent discovery of few potential antidotes. This review summarizes the major trials that led to the approval of these agents and their exclusion criteria helping physicians understand which patient types might not benefit from these agents. It provides clinical pearls invaluable in everyday practice such as transitioning between traditional and novel anticoagulants, dose adjustments for high risk populations, drug interactions and cost analysis. Futhermore, the review provides direct comparisons with warfarin and indirect comparisons among the novel agents in terms of efficacy and bleeding risk narrating the numbers of patients with intracranial, gastrointestinal and fatal hemorrhages in each of the major trials. We hope that this review will help the physicians inform their patients about the benefits and risks of these agents and enable them to make an informed selection of the most appropriate anticoagulant. PMID:27594818
Objective. To evaluate the impact of animated videos of oral solid dosage form manufacturing as visual instructional aids on pharmacy students’ perception and learning. Design. Data were obtained using a validated, paper-based survey instrument designed to evaluate the effectiveness, appeal, and efficiency of the animated videos in a pharmaceutics course offered in spring 2014 and 2015. Basic demographic data were also collected and analyzed. Assessment data at the end of pharmaceutics course was collected for 2013 and compared with assessment data from 2014, and 2015. Assessment. Seventy-six percent of the respondents supported the idea of incorporating animated videos as instructional aids for teaching pharmaceutics. Students’ performance on the formative assessment in 2014 and 2015 improved significantly compared to the performance of students in 2013 whose lectures did not include animated videos as instructional aids. Conclusions. Implementing animated videos of oral solid dosage form manufacturing as instructional aids resulted in improved student learning and favorable student perceptions about the instructional approach. Therefore, use of animated videos can be incorporated in pharmaceutics teaching to enhance visual learning. PMID:27899837
Nair, Anita; Abrahamsson, Bertil; Barends, Dirk M; Groot, D W; Kopp, Sabine; Polli, James E; Shah, Vinod P; Dressman, Jennifer B
Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate-release (IR) solid oral dosage forms containing the antimalarial drug primaquine phosphate as the only active pharmaceutical ingredient (API) are reviewed. On the basis of permeability data and solubility studies, primaquine phosphate was found to be "highly soluble" and "highly permeable" API, thus conforming to Class I of the Biopharmaceutical Classification System (BCS). It has a wide therapeutic index. BCS-conform dissolution studies showed the products to be rapidly dissolving. No data pertaining to BE or bioinequivalence of IR primaquine phosphate products could be located in open literature. On the basis of the available data, a biowaiver-procedure-based approval can be recommended for IR solid oral dosage forms of primaquine phosphate, provided the generic product contains excipients present in products already approved by the International Conference on Harmonisation or associated countries in similar amounts and the test and reference products meet the dissolution criteria for "rapidly dissolving" (>85% drug release in 30 min in standard media at pH 1.2, 4.5, and 6.8; similarity factor (f(2)) > 50) or "very rapidly dissolving" products (>85% drug release in 15 min in standard media at pH 1.2, 4.5, and 6.8).
Delvadia, Poonam R; Barr, William H; Karnes, H Thomas
This research describes the development and validation of a biorelevant in vitro release/permeation system to predict the in vivo performance of oral transmucosal dosage forms. The system is a biorelevant bidirectional transmucosal apparatus which allows better simulation of oral cavity physiological variables in comparison to compendial dissolution apparatuses and therefore may be a better predictor of in vivo behavior. The feasibility of the bidirectional apparatus was studied using smokeless tobacco (snus) as a model oral transmucosal product. In this research, nicotine release and permeation was investigated from commercially available snus using a modified USP IV flow-through apparatus, a commercially available vertical diffusion cell and a fabricated novel bidirectional transmucosal apparatus. The percent nicotine released/permeated was utilized as an input function for the prediction of in vivo plasma nicotine profiles by back calculation based on the Wagner-Nelson method. The prediction errors in C(max) and AUC(0-∞) with the USP IV flow-through device, vertical diffusion cell and novel apparatus were 4.03, 22.85 and 1.59 and -5.85, 5.85 and -9.27% respectively. This work demonstrated the suitability of the novel bidirectional transmucosal apparatus for predicting the in vivo behavior of oral transmucosal products.
Gerotziafas, Grigoris T; Mahé, Isabelle; Elalamy, Ismail
Patients with cancer have a 6–7-fold higher risk of venous thromboembolism (VTE) as compared with non-cancer patients. Effective and safe anticoagulation for the prevention and treatment of VTE is the cornerstone of the management of patients with cancer, aiming to decrease morbidity and mortality and to improve quality of life. Unfractionated heparin, low molecular weight heparins, fondaparinux and vitamin K antagonists (VKAs) are used in the prevention and treatment of VTE in cancer patients. Heparins and fondaparinux are administered subcutaneously. VKAs are orally active, but they have a narrow therapeutic window, numerous food and drug interactions, and treatment requires regular laboratory monitoring and dose adjustment. These limitations among others have important negative impact on the quality of life of patients and decrease adherence to the treatment. New orally active anticoagulant (NOAC) agents are specific inhibitors of activated factor Xa (FXa) (rivaroxaban and apixaban) or thrombin (dabigatran). It is expected that NOACs will improve antithrombotic treatment. Cancer patients are a particular group that could benefit from treatment with NOACs. However, NOACs present some significant interactions with drugs frequently used in cancer patients, which might influence their pharmacokinetics, compromising their efficacy and safety. In the present review, we analyzed the available data from the subgroups of patients with active cancer who were included in Phase III clinical trials that assessed the efficacy and safety of NOACs in the prevention and treatment of VTE. The data from the Phase III trials in prophylaxis of VTE by rivaroxaban or apixaban highlight that these two agents, although belonging to the same pharmacological group (direct inhibitors of factor Xa), have substantially different profiles of efficacy and safety, especially in hospitalized acutely ill medical patients with active cancer. A limited number of patients with VTE and active
Background Stroke incidence increases with age. Atrial fibrillation (AF) is an important risk factor for ischemic stroke and its incidence also increases with age. However oral anticoagulant therapy (OAT) tends to be underused in the elderly population. Methods Elderly patients (> = 80 years) with an ischemic stroke admitted in our department between 1/7/2003 and 31/6/2005 were prospectively evaluated. Baseline characteristics, risk factors, treatment and etiology according to TOAST criteria were recorded. Patients treated with OAT were followed up in order to assess any side effect and stroke recurrence. Mean follow-up was of 19.5 months (7-45) from discharge. Results Sixty four out of a hundred and fifty nine elderly patients (40.25%) were classified as cardioembolic; mean age was 84.5 years (80-97) and 64.6% were women. AF had been previously identified in 60% of them (16.9% were on OAT and 40.6% on antiplatelet therapy). At discharge, 32 patients (49.2%) were on OAT. In the follow-up 4 patients (12.5%) suffered systemic haemorrhages (3 urinary, 1 gastrointestinal bleeding), with no change in their functional status. Mean INR in this group was 5.9 [3-11] and, in 3 of them, OAT was cancelled. No brain haemorrhages were recorded. Ischemic stroke recurred in 4 patients (INR < 1.8 in 3 of them; the other, INR 2.35). Three patients had died at the end of the follow-up, one of them as a consequence of ischemic stroke recurrence. Discussion Twenty eight point eight of stroke patients admitted in the period of study were >80 years. The high proportion of cardioembolic strokes in this age segment contrasts with the general underuse of OAT as antithrombotic prophylaxis. Our study suggests that OAT is a safe strategy when carefully prescribed, even for elderly patients. PMID:20525389
Katsanos, Aristeidis H.; Mavridis, Dimitris; Parissis, John; Deftereos, Spyridon; Frogoudaki, Alexandra; Vrettou, Agathi-Rosa; Ikonomidis, Ignatios; Chondrogianni, Maria; Safouris, Apostolos; Filippatou, Angeliki; Voumvourakis, Konstantinos; Triantafyllou, Nikos; Ellul, John; Karapanayiotides, Theodore; Giannopoulos, Sotirios; Alexandrov, Anne W.; Alexandrov, Andrei V.; Tsivgoulis, Georgios
Background: Novel oral anticoagulants (NOACs) have shown to be both safe and effective for ischemic stroke prevention in patients with nonvalvular atrial fibrillation (NVAF). We conducted a network meta-analysis (NMA) using published data from secondary prevention subgroups of different phase III randomized clinical trials (RCTs) comparing individual NOACs with warfarin. Methods: Eligible studies were identified by searching MEDLINE and SCOPUS and the Cochrane Central Register of Controlled Trials databases. First, we conducted a pairwise meta-analysis for each pairwise comparison, and then we performed NMA to combine direct and indirect evidence for any given pair of treatments. The comparative effects of all NOACs against warfarin were ranked with the surface under the cumulative ranking (SUCRA) curve for each outcome. Results: We identified four RCTs (including 15,240 patients) comparing individual NOACs (apixaban, dabigatran, rivaroxaban) with warfarin. Using indirect evidence, dabigatran was related to a significantly lower risk of hemorrhagic stroke compared with rivaroxaban [risk ratio (RR) 0.28; 95% confidence interval (CI) 0.11–0.75], while rivaroxaban was associated with a significantly lower risk of major gastrointestinal bleeding compared with dabigatran (RR 0.14; 95% CI 0.03–0.74). We also performed clustered ranking plot for the primary efficacy and safety endpoints to identify the treatment with the probably best benefit-to-risk ratio profile. Conclusions: The three NOACs showed differences in terms of safety and efficacy for secondary stroke prevention in NVAF. Our findings can serve only as hypothesis generation and require independent confirmation in head-to-head RCTs, owing to the sparse available evidence and increased uncertainty in both indirect effect estimates and ranking of treatments. PMID:27582891
Background Patients on oral anticoagulant therapy (OAT) require regular testing of the prothrombin time (PT) and the international normalised ratio (INR) to monitor their blood coagulation level to avoid complications of either over or under coagulation. PT/INR can be tested by a healthcare professional or by the patient. The latter mode of the testing is known as patient self-testing or home testing. The objective of this study was to elicit patients' perspectives and experiences regarding PT/INR self-testing using portable coagulometer devices. Methods Internet blog text mining was used to collect 246 blog postings by 108 patients, mainly from the USA and the UK. The content of these qualitative data were analysed using XSight and NVivo software packages. Results The key themes in relation to self-testing of OAT identified were as follows: Patient benefits reported were time saved, personal control, choice, travel reduction, cheaper testing, and peace of mind. Equipment issues included high costs, reliability, quality, and learning how to use the device. PT/INR issues focused on the frequency of testing, INR fluctuations and individual target (therapeutic) INR level. Other themes noted were INR testing at laboratories, the interactions with healthcare professionals in managing and testing OAT and insurance companies' involvement in acquiring the self-testing equipment. Social issues included the pain and stress of taking and testing for OAT. Conclusions Patients' blogs on PT/INR testing provide insightful information that can help in understanding the nature of the experiences and perspectives of patients on self-testing of OAT. The themes identified in this paper highlight the substantial complexities involved in self-testing programmes in the healthcare system. Thus, the issues elicited in this study are very valuable for all stakeholders involved in developing effective self-testing strategies in healthcare that are gaining considerable current momentum
Cappellari, Manuel; Carletti, Monica; Danese, Alessandra; Bovi, Paolo
Direct oral anticoagulants (DOACs) are superior to warfarin in reduction of the intracranial bleeding risk. The aim of the present study was to assess whether early DOAC introduction (1-3 days after onset) in stroke patients with non-valvular atrial fibrillation (nVAF) may be safe and effective, compared with DOAC introduction after 4-7 days. We conducted a prospective analysis based on data collected from 147 consecutive nVAF patients who started DOAC within 7 days after stroke onset. In all patients, we performed pre-DOAC CT scan 24-36 h after onset and follow-up CT scan at 7 days after DOAC introduction. Outcome measures were post-DOAC intracranial bleeding (new any intracerebral hemorrhage (ICH) in patients with pre-DOAC infarct without hemorrhagic transformation (HT) or expansion of ICH in patients with pre-DOAC infarct with asymptomatic HT) and post-DOAC recurrent ischemic stroke (any new ischemic infarct) on follow-up CT scan. 97 patients started DOAC after 1-3 days and 50 patients started DOAC after 4-7 days. On pre-DOAC CT scan, 132 patients had an infarct without HT and 15 an infarct with asymptomatic HT. On follow-up CT scan, new any ICH was noted in seven patients (asymptomatic in 6) and asymptomatic expansion of ICH in one patient. We found no association between early DOAC introduction and intracranial bleeding. Large infarct remained the only independent predictor of post-DOAC intracranial bleeding. No patients suffered recurrent ischemic stroke after DOAC introduction. Early DOAC introduction might be safe in carefully selected patients with nVAF who experience small- and medium-sized cardioembolic ischemic strokes. Further investigation will be needed.
Shohin, Igor E; Kulinich, Julia I; Ramenskaya, Galina V; Abrahamsson, Bertil; Kopp, Sabine; Langguth, Peter; Polli, James E; Shah, Vinod P; Groot, D W; Barends, Dirk M; Dressman, Jennifer B
Literature and experimental data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate-release (IR) solid oral dosage forms containing ketoprofen are reviewed. Ketoprofen's solubility and permeability, its therapeutic use and therapeutic index, pharmacokinetic properties, data related to the possibility of excipient interactions, and reported BE/bioavailability (BA)/dissolution data were taken into consideration. The available data suggest that according to the current Biopharmaceutics Classification System (BCS) and all current guidances, ketoprofen is a weak acid that would be assigned to BCS Class II. The extent of ketoprofen absorption seems not to depend on formulation or excipients, so the risk of bioinequivalence in terms of area under the curve is very low, but the rate of absorption (i.e., BE in terms of peak plasma concentration, C(max) ) can be altered by formulation. Current in vitro dissolution methods may not always reflect differences in terms of C(max) for BCS Class II weak acids; however, such differences in absorption rate are acceptable for ketoprofen with respect to patient risks. As ketoprofen products may be taken before or after meals, the rate of absorption cannot be considered crucial to drug action. Therefore, a biowaiver for IR ketoprofen solid oral dosage form is considered feasible, provided that (a) the test product contains only excipients present also in IR solid oral drug products containing ketoprofen, which are approved in International Conference on Harmonisation or associated countries, for instance, as presented in this paper; (b) both the test drug product and the comparator dissolve 85% in 30 min or less in pH 6.8 buffer; and (c) test product and comparator show dissolution profile similarity in pH 1.2, 4.5, and 6.8. When one or more of these conditions are not fulfilled, BE should be established in vivo.
Hayward, Rodney C.
Provides background information on the development and action of the coumarin family of anticoagulants, focusing on an experimental procedure for the synthesis of dicumerol. Includes procedures used and safety considerations. (JM)
Díez-Manglano, Jesús; Bernabeu-Wittel, Máximo; Murcia-Zaragoza, José; Escolano-Fernández, Belén; Jarava-Rol, Guadalupe; Hernández-Quiles, Carlos; Oliver, Miguel; Sanz-Baena, Susana
Many patients with non-neoplastic disease develop atrial fibrillation in advanced stages of their disease. The aim of this study is to determine the factors associated with the use of oral anticoagulants in patients with atrial fibrillation and non-neoplastic medical disease in a terminal stage, and whether their use is associated with a longer survival. Design is prospective, observational, multicentre study. Patients with atrial fibrillation and non-neoplastic disease (severe not reversible organ insufficiency) in a terminal stage were included between February 2009 and September 2010. A 6-month follow-up was carried out. We included 314 patients with a mean (SD) age of 82.6 (7.0) years. Their mean (SD) scores in CHADS2 and ATRIA scales were 3.4 (1.2) and 4.7 (2.0), respectively. Anticoagulants were prescribed to 112 (37.5 %) patients. The use of anticoagulants was associated with age (OR 0.96 95 % CI 0.93-0.99, p = 0.046) and to the Barthel index (OR 1.01 95 % CI 1.00-1.02; p = 0.034). After performing a propensity score matching analysis, 262 patients were included in the survival analysis. After 6 months, 133 (50.8 %) patients were dead. The mortality is higher among patients who are not treated with oral anticoagulants (57.1 vs. 39.4 %; p = 0.006), but it is independently associated only with the Barthel index score (HR 0.99 95 % CI 0.98-1.00; p = 0.039), delirium (HR 1.60, 95 % CI 1.08-2.36; p = 0.018), anorexia (HR 1.58 95 % CI 1.05-2.38; p = 0.027), and with the use of calcium channel blockers (HR 0.50 95 % CI 0.30-0.84; p = 0.009). In patients with atrial fibrillation and non-neoplastic disease in a terminal stage, the use of oral anticoagulants is not independently associated with a higher probability of survival.
Tagaya, Manaka; Yoshikawa, Daiji; Sugishita, Yoshinori; Yamauchi, Fumi; Ito, Takehiro; Kamada, Tomohito; Yoshinaga, Masataka; Mukaide, Daisuke; Fujiwara, Wakaya; Yokoi, Hiroatsu; Hayashi, Mutsuharu; Watanabe, Eiichi; Ishii, Junichi; Ozaki, Yukio; Izawa, Hideo
New oral anticoagulants (NOACs) are now clinically available. However, few studies have demonstrated which patients with non-valvular atrial fibrillation (NVAF) actually receive NOACs in a clinical setting. We analyzed 182 NVAF patients who received oral anticoagulants. Clinical backgrounds and the risk of stroke, systemic embolism, and bleeding associated with oral anticoagulants were investigated. Seventy-three (40 %) patients were treated with NOACs and 109 (60 %) patients were treated with warfarin. A significantly lower mean number of bleeding risk factors was observed among the patients treated with NOACs than among those treated with warfarin (P = 0.010). Of the bleeding risk factors, NOACs were significantly less frequently prescribed in patients with a bleeding history and elderly subjects (>65 years) than in those who received warfarin (P < 0.001 and P = 0.029). A multivariate logistic regression analysis revealed that CHF and bleeding history were independently and significantly associated with the administration of NOACs (P = 0.047 and P = 0.003). The rate of a history of intracranial hemorrhage was comparable between the patients treated with NOACs and those treated with warfarin (P = 1.000). Significantly lower rates of a history of gastrointestinal and other minor bleeding were observed in the patients who received NOACs versus those who received warfarin (P = 0.001 and P = 0.026). NOACs were less frequently prescribed in patients with a history of bleeding, especially those with a history of gastrointestinal bleeding in a clinical setting.
Genina, Natalja; Fors, Daniela; Vakili, Hossein; Ihalainen, Petri; Pohjala, Leena; Ehlers, Henrik; Kassamakov, Ivan; Haeggström, Edward; Vuorela, Pia; Peltonen, Jouko; Sandler, Niklas
We combined conventional inkjet printing technology with flexographic printing to fabricate drug delivery systems with accurate doses and tailored drug release. Riboflavin sodium phosphate (RSP) and propranolol hydrochloride (PH) were used as water-soluble model drugs. Three different paper substrates: A (uncoated woodfree paper), B (triple-coated inkjet paper) and C (double-coated sheet fed offset paper) were used as porous model carriers for drug delivery. Active pharmaceutical ingredient (API) containing solutions were printed onto 1 cm × 1 cm substrate areas using an inkjet printer. The printed APIs were coated with water insoluble polymeric films of different thickness using flexographic printing. All substrates were characterized with respect to wettability, surface roughness, air permeability, and cell toxicity. In addition, content uniformity and release profiles of the produced solid dosage forms before and after coating were studied. The substrates were nontoxic for the human cell line assayed. Substrate B was smoothest and least porous. The properties of substrates B and C were similar, whereas those of substrate A differed significantly from those of B, C. The release kinetics of both printed APIs was slowest from substrate B before and after coating with the water insoluble polymer film, following by substrate C, whereas substrate A showed the fastest release. The release rate decreased with increasing polymer coating film thickness. The printed solid dosage forms showed excellent content uniformity. So, combining the two printing technologies allowed fabricating controlled-release oral dosage forms that are challenging to produce using a single technique. The approach opens up new perspectives in the manufacture of flexible doses and tailored drug-delivery systems.
[Treatment with inhibitors of new oral direct anticoagulants in patients with severe bleedings or urgent surgical procedures. The new dabigatran antidote: the place of idarucizumab in clinical practice].
Only vitamin K antagonists could be applied as oral anticoagulants over the past six decades. Coumarols have narrow therapeutic range, and unpredictable anticoagulant effects are resulted by multiple drug interactions. Therefore, regular routine monitoring of the international normalized ratio is necessary. There are two groups of factor-specific anticoagulants: molecules with anti-FIIa (dabigatran) and anti-FXa (rivaroxaban, apixaban and edoxaban) effect. Author summarizes the most important clinical features of the new oral anticoagulants, their indications and the possibilities of laboratory controls. Bleedings are the most important side effects of anticoagulants. This review summarizes the current published evidences for new oral anticoagulants reversal (non-specific and specific) agents, especially in cases with severe acute bleedings or urgent surgery procedures. It reports on how to use inhibitors, the recommended doses and the most important clinical results. The review focuses on idarucizumab - already approved by the U.S. Food and Drug Administration and the European Medicines Agency - which has a key role as the first specific inhibitor of dabigatran.
Stone, James A; Earl, Karen M; O'Neill, Blair J; Sharma, Mukul; Huynh, Thao; Leblanc, Kori; Ward, Richard; Teal, Philip A; Cox, Jafna L
Misalignment between evidence-informed clinical care guideline recommendations and reimbursement policy has created care gaps that lead to suboptimal outcomes for patients denied access to guideline-based therapies. The purpose of this article is to make the case for addressing this growing access barrier to optimal care. Stroke prevention in atrial fibrillation (AF) is discussed as an example. Stroke is an extremely costly disease, imposing a significant human, societal, and economic burden. Stroke in the setting of AF carries an 80% probability of death or disability. Although two-thirds of these strokes are preventable with appropriate anticoagulation, this has historically been underprescribed and poorly managed. National and international guidelines endorse the direct oral anticoagulants as first-line therapy for this indication. However, no Canadian province has provided these agents with an unrestricted listing. These decisions appear to be founded on silo-based cost assessment-the drug costs rather than the total system costs-and thus overlook several important cost-drivers in stroke. The discordance between best scientific evidence and public policy requires health care providers to use a potentially suboptimal therapy in contravention of guideline recommendations. It represents a significant obstacle for knowledge translation efforts that aim to increase the appropriate anticoagulation of Canadians with AF. As health care professionals, we have a responsibility to our patients to engage with policy-makers in addressing and resolving this barrier to optimal patient care.
Gendron, Nicolas; Smadja, David M
Direct oral anticoagulants (DAO), anti-IIa or anti-Xa, are intended to be widely used for the treatment and prevention of thrombotic disorders in venous thromboembolic disease and atrial fibrillation as an alternative of vitamin K antagonists (VKA). Despite predictable pharmacological properties, spontaneous or provoked hemorrhagic risks by DAO are major limitations. Thus, after few years of inconsistence concerning biological implication and in particular coagulation tests, it is now established that we need biology to evaluate hemorrhagic risk before surgery or in hemorrhagic cases.
Kuntić, Vesna; Pejić, Natasa; Ivković, Branka; Vujić, Zorica; Ilić, Katarina; Mićić, Svetlana; Vukojević, Vladana
A rapid and sensitive assay for quantitative determination of rutin in oral dosage forms based on isocratic reversed phase high performance liquid chromatography (RP-HPLC) was developed and validated. Using a C(18) reverse-phase analytical column, the following conditions were chosen as optimal: mobile phase methanol-water 1:1 (v/v), pH 2.8 (adjusted with phosphoric acid), flow rate=1 mL min(-1) and temperature T=40.0 degrees C. Linearity was observed in the concentration range 8-120 microg mL(-1) with a correlation coefficient of 0.99982 and the limit of detection (LOD)=2.6 microg mL(-1), and limit of quantification (LOQ)=8.0 microg mL(-1). Intra- and inter-day precision were within acceptable limits. Robustness test indicated that the mobile phase composition and pH influence mainly the separation. The proposed method allowed direct determination of rutin in pharmaceutical dosage forms in the presence of excipients, but is not suitable for preparations where compounds structurally/chemically related to rutin may be present.
Mc Gillicuddy, Aoife; Kelly, Maria; Sweeney, Catherine; Carmichael, Ann; Crean, Abina M; Sahm, Laura J
Age-related pharmacological changes complicate oral dosage form (ODF) suitability for older adults. The aim of this study was to investigate the appropriateness of ODF for older adults by determining the prevalence of ODF modifications in an aged care facility in Ireland. Drug charts for eligible patients were obtained. Details of all medications administered were recorded. ODF modifications were examined to determine if they were evidence-based: defined as complying with the product license or best practice guidelines (BPG). In total, of 111 patients, 35.1% received at least one modified medicine. Medicines were most commonly modified to facilitate fractional dosing (82.0%). Of the 68 instances of medicine modification, 35.3% complied with the product license. Of the 44 unlicensed modifications, 14 complied with BPG. Therefore, 44.1% of modifications were not evidence-based. This study highlights that clinicians have to routinely tailor commercial ODF to meet older patients' needs despite the lack of an evidence-base for almost half of these modifications. The main factor contributing to these modifications is the lack of appropriate, licensed dosage forms. However, reimbursement policies also play a role. Research is needed to optimise medicine administration and to provide clinicians with much needed evidence to support their daily practice.
Kristo, Katalin; Bajdik, János; Márki, Arpád; Eros, István; Falkay, György; Hödi, Klára
The main objective of this study was to process the human alpha-interferon for the solid dosage form. The first step was the preparation of the intermediate product for the tablet making. Fluid bed apparatus with top spray method was applied for the layering of powdered cellulose with human alpha-interferon solutions. The intermediate product was compressed into tablet and an enteric solvent coating of the tablets was made in a fluid bed apparatus with Wurster method. The physical parameters were detected. These fitted the Ph. Eur. and the mechanical properties of the tablets were appropriate for coating in fluid bed apparatus. The tablets agree with the requirements of Ph. Eur. and the active agent was not dissolved in gastric juice. An animal test was also performed. The human alpha-interferon in the blood of the animals was detected with ELISA method. The human alpha-interferon specific kit was used. The active ingredient dissolved from the tablets was absorbed from the ileum. The solid dosage form containing human alpha-interferon was prepared; this can make oral application of human alpha-interferon possible.
Dahan, Arik; Wolk, Omri; Zur, Moran; Amidon, Gordon L; Abrahamsson, Bertil; Cristofoletti, Rodrigo; Groot, D W; Kopp, Sabine; Langguth, Peter; Polli, James E; Shah, Vinod P; Dressman, Jennifer B
The present monograph reviews data relevant to applying the biowaiver procedure for the approval of immediate-release multisource solid dosage forms containing codeine phosphate. Both biopharmaceutical and clinical data of codeine were assessed. Solubility studies revealed that codeine meets the "highly soluble" criteria according to World Health Organization (WHO), the European Medicines Agency (EMA), and the United States Food and Drug Administration (US FDA). Codeine's fraction of dose absorbed in humans was reported to be high (>90%) based on cumulative urinary excretion of drug and drug-related material following oral administration. The permeability of codeine was also assessed to be high in both Caco-2 monolayers and rat intestinal perfusion studies. The main risks associated with codeine, that is, toxicity (attributed to CYP2D6 polymorphism) and its abuse potential, are present irrespective of the dosage form, and do not need to be taken into account for bioequivalence (BE) considerations. Taken together, codeine is a class 1 drug with manageable risk and is a good candidate for waiver of in vivo BE studies.
Soares, Kelen C C; Rediguieri, Camila F; Souza, Jacqueline; Serra, Cristina Helena R; Abrahamsson, Bertil; Groot, D W; Kopp, Sabine; Langguth, Peter; Polli, James E; Shah, Vinod P; Dressman, Jennifer
Literature data on the properties of zidovudine relevant to waiver of in vivo bioequivalence (BE) testing requirements for the approval of immediate-release (IR) solid oral dosage forms containing zidovudine alone or in combination with other active pharmaceutical ingredients (APIs) are reviewed. Solubility, dissolution, and permeability data for zidovudine, along with its dosing schedule, therapeutic index and pharmacokinetic properties, and reports related to BE/bioavailability were all taken into consideration. Data for solubility and permeability suggest that zidovudine belongs to Class I according to the Biopharmaceutics Classification System. Also, zidovudine is not a narrow therapeutic index drug. Although five out of 13 formulations tested in vivo (mostly of unreported composition) failed to show BE, it appears that in vitro studies performed according to biowaiver methods could predict in vivo behavior. Nevertheless, it is highly recommended that if a biowaiver is to be applied, excipient choices be limited to those found in IR drug products approved in International Conference on Harmonisation (ICH) or associated countries in the same dosage form (Table 2 of this monograph), in their usual amounts. These conclusions apply to products containing zidovudine as the only API and also to fixed combination products containing zidovudine with respect to the zidovudine component of the formulation.
Manzo, R H; Olivera, M E; Amidon, G L; Shah, V P; Dressman, J B; Barends, D M
Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release (IR) solid oral dosage forms containing amitriptyline hydrochloride are reviewed. Its therapeutic uses, its pharmacokinetic properties, the possibility of excipient interactions and reported BE/bioavailability (BA) problems are also taken into consideration. Literature data indicates that amitriptyline hydrochloride is a highly permeable active pharmaceutical ingredient (API). Data on the solubility according to the current Biopharmaceutics Classification System (BCS) were not fully available and consequently amitriptyline hydrochloride could not be definitively assigned to either BCS Class I or BCS Class II. But all evidence taken together, a biowaiver can currently be recommended provided that IR tablets are formulated with excipients used in existing approved products and that the dissolution meets the criteria defined in the Guidances.
Shammas, Nicolas W; Shammas, Gail A; Jones-Miller, Susan; Gumpert, Mileah Rose; Gumpert, Miranda Jade; Harb, Christine; Chammas, Majid Z; Shammas, W John; Khalafallah, Rommy A; Barzgari, Amy; Bou Dargham, Bassel; Daher, Ghassan E; Rachwan, Rayan Jo; Shammas, Andrew N
Background It is unclear whether patients on oral anticoagulants (OAC) undergoing a procedure using common femoral artery access have higher adverse events when compared to patients who are not anticoagulated at the time of the procedure. Methods We retrospectively reviewed data from consecutive patients who underwent a cardiac procedure at a tertiary medical center. Patients were considered (group A) fully or partially anticoagulated if they had an international normalized ratio (INR) ≥1.6 on the day of the procedure or were on warfarin or new OAC within 48 h and 24 h of the procedure, respectively. The nonanticoagulated group (group B) had an INR <1.6 or had stopped their warfarin and new OAC >48 h and >24 h preprocedure, respectively. The index primary end point of the study was defined as the composite end point of major bleeding, vascular complications, or cardiovascular-related death during index hospitalization. The 30-day primary end point was defined as the occurrence of the index primary end point and up to 30 days postprocedure. Results A total of 779 patients were included in this study. Of these patients, 27 (3.5%) patients were in group A. The index primary end point was met in 11/779 (1.4%) patients. The 30-day primary composite end point was met in 18/779 (2.3%) patients. There was no difference in the primary end point at index between group A (1/27 [3.7%]) and group B (10/752 [1.3%]; P=0.3155) and no difference in the 30-day primary composite end point between group A (2/27 [7.4%]) and group B (16/752 [2.1%]; P=0.1313). Multivariable analysis showed that a low creatinine clearance (odds ratio [OR] =0.56; P=0.0200) and underweight patients (<60 kg; OR =3.94; P=0.0300) were independent predictors of the 30-day primary composite end point but not oral anticoagulation (P=0.1500). Conclusion Patients on OAC did not have higher 30-day major adverse events than those who were not anticoagulated at index procedure.
Zapata-Wainberg, Gustavo; Ximénez-Carrillo Rico, Álvaro; Benavente Fernández, Lorena; Masjuan Vallejo, Jaime; Gállego Culleré, Jaime; Freijó Guerrero, María del Mar; Egido, José; Gómez Sánchez, José Carlos; Martínez Domeño, Alejandro; Purroy García, Francisco; Vives Pastor, Bárbara; Blanco González, Miguel; Vivancos, José
Background Vitamin K antagonist oral anticoagulants (VKA-OACs) are effective for primary and secondary prevention of embolic events. The rate of haemorrhagic neurological complications in patients admitted to neurology departments in Spain is not yet known. Aims We aimed to determine the clinical and epidemiological characteristics of patients with intracranial haemorrhage secondary to VKA-OACs as well as the incidence of this severe complication. Methods We conducted a retrospective, descriptive, multi-centre study using information from the medical records of all patients admitted to neurology departments, diagnosed with spontaneous intracranial haemorrhage, and treated with VKA-OACs within a 1-year period. We collected demographic and care data from centres, patients' medical records [demographic data, medical history, haemorrhage origin, vascular risk factors, concomitant treatment, and National Institutes of Health Stroke Scale (NIHSS) scores], and patients' outcome at 3 months [independence (modified Rankin Scale score <3) and mortality rate]. Results Twenty-one hospitals serving a population of 8,155,628 inhabitants participated in the study. The total number of cases was 235, the mean age was 78.2 (SD 9.4) years, and the baseline NIHSS score was 11.6 (SD 9.5; median 9; interquartile range 14). The VKA-OACs used were acenocoumarol in 95.3% (224 patients) and warfarin in 4.7% (11 patients). The haemorrhage origin was deep in 29.8%, lobar in 25.5%, intraventricular in 11.5%, extensive in 17.4% (>100 ml), cerebellar in 12.3%, and in the brainstem in 3.4%. The international normalised ratio was within therapeutic ranges at admission (according to indication) in 29.4% (69 patients). The global incidence (cases per 100,000 inhabitants per year) is 2.88. The in-hospital mortality rate was 40%, and 24.3% of the patients were independent at 3 months, while the mortality at 3 months was 42.6%. Conclusion VKA-OAC treatment is associated with a large percentage of all
Bahrmann, Philipp; Harms, Fred; Schambeck, Christian Martin; Wehling, Martin; Flohr, Jürgen
Geriatric patients with non-valvular atrial fibrillation (AF) are increasingly being treated with novel oral anticoagulants (NOAC) to prevent ischemic stroke. This article highlights the outcome of an expert meeting on the practical use of NOAC in elderly patients. An interdisciplinary group of experts discussed the current situation of stroke prevention in geriatric patients and its practical management in daily clinical practice. The topic was examined through focused impulse presentations and critical analyses as the basis for the expert consensus. The key issues are summarized in this paper. The European Society of Cardiology (ESC) guidelines from 2012 for the management of patients with non-valvular AF recommend NOAC as the preferred treatment and vitamin K antagonists (VKA) only as an alternative option. Currently, the NOAC factor Xa inhibitors apixaban and rivaroxaban and the thrombin inhibitor dabigatran are more commonly used in clinical practice for patients with AF. Although these drugs have many similarities and are often grouped together it is important to recognize that the pharmacology and dose regimes differ between compounds. Especially n elderly patients NOAC drugs have some advantages compared to VKA, e.g. less drug-drug interactions with concomitant medication and a more favorable risk-benefit ratio mostly driven by the reduction of bleeding. Treatment of anticoagulation in geriatric patients requires weighing the serious risk of stroke against an equally high risk of major bleeding and pharmacoeconomic considerations. Geriatric patients in particular have the greatest benefit from NOAC, which can also be administered in cases of reduced renal function. Regular control of the indications is indispensable, as also for all other medications of the patient. The use of NOAC should certainly not be withheld from geriatric patients who have a clear need for oral anticoagulation.
Ciper, Mesut; Bodmeier, Roland
Fast disintegrating capsules for administration in the oral cavity were prepared either by perforation or by vacuum-drying of conventional hard capsules. When compared to other fast disintegrating dosage forms (e.g. lyophilized sponges or tablets), these capsules have various advantages, in particular, a high drug loading capacity and no compression steps. The disintegration time of conventional hard gelatin capsules (HGC) was reduced from 91 to 39 s by introducing 6-10 small holes (diameter =25-50 microm) into the capsule shell. Vacuum-drying of conventional hard gelatin capsules resulted in brittle capsules, which broke rapidly in the oral cavity. The brittleness of the hard gelatin capsules correlated well with their moisture content. The critical moisture value for sufficient brittleness of hard gelatin capsules was <4% w/w. In contrast, HPMC capsules remained flexible, even at low moisture content. The moisture uptake of various capsule fillers was in the order of Avicel PH101 > lactose > Avicel PH112 > or = mannitol. Hard gelatin capsules filled with mannitol and packaged in bottles with silica gel kept their desired brittleness during 6 months storage at various relative humidities.
Management of major bleeding complications and emergency surgery in patients on long-term treatment with direct oral anticoagulants, thrombin or factor-Xa inhibitors: proposals of the working group on perioperative haemostasis (GIHP) - March 2013.
Pernod, Gilles; Albaladejo, Pierre; Godier, Anne; Samama, Charles M; Susen, Sophie; Gruel, Yves; Blais, Normand; Fontana, Pierre; Cohen, Ariel; Llau, Juan V; Rosencher, Nadia; Schved, Jean-François; de Maistre, Emmanuel; Samama, Meyer M; Mismetti, Patrick; Sié, Pierre
Direct new oral anticoagulants (NOACs) - inhibitors of thrombin or factor Xa - are intended to be used largely in the treatment of venous thromboembolic disease or the prevention of systematic embolism in atrial fibrillation, instead of vitamin K antagonists. Like any anticoagulant treatment, they are associated with spontaneous or provoked haemorrhagic risk. Furthermore, a significant proportion of treated patients are likely to be exposed to emergency surgery or invasive procedures. Given the absence of a specific antidote, the action to be taken in these situations must be defined. The lack of data means that it is only possible to issue proposals rather than recommendations, which will evolve according to accumulated experience. The proposals presented here apply to dabigatran (Pradaxa(®)) and rivaroxaban (Xarelto(®)); data for apixaban and edoxaban are still scarce. For urgent surgery with haemorrhagic risk, the drug plasma concentration should be less or equal to 30ng/mL for dabigatran and rivaroxaban should enable surgery associated with a high bleeding risk. Beyond that, if possible, the intervention should be postponed by monitoring the drug concentration. The course to follow is then defined according to the NOAC and its concentration. If the anticoagulant dosage is not immediately available, worse propositions, based on the usual tests (prothrombin time and activated partial thromboplastin time), are presented. However, these tests do not really assess drug concentration or the risk of bleeding that depends on it. In case of serious bleeding in a critical organ, the effect of anticoagulant therapy should be reduced using a non-specific procoagulant drug as a first-line approach: activated prothrombin complex concentrate (aPCC) (FEIBA(®) 30-50U/kg) or non-activated PCC (50U/kg). In addition, for any other type of severe haemorrhage, the administration of a procoagulant drug, which is potentially thrombogenic in these patients, is discussed according
Kruse-Loesler, Birgit; Kelker, Matthias; Kleinheinz, Johannes
Background Dental surgery can be carried out on patients under oral anticoagulation therapy by using haemostyptic measures. The aim of the study was a comparative analysis of coagulation by laboratory methods and immediate patient diagnosis on the day of the planned procedure. Methods On the planned day of treatment, diagnoses were carried out on 298 patients for Prothrombin Time (PT), the International Normalised Ratio (INR), and Partial Thromboplastin Time (PTT). The decision to proceed with treatment was made with an INR < 4.0 according to laboratory results. Results Planned treatment did not go ahead in 2.7% of cases. Postoperatively, 14.8% resulted in secondary bleeding, but were able to be treated as out-patients. 1.7% had to be treated as in-patients. The average error between the immediate diagnosis and the laboratory method: 95% confidence interval was -5.8 ± 15.2% for PT, -2.7 ± 17.9 s for PTT and 0.23 ± 0.80 for INR. The limits for concordance were 9.4 and -21.1% for PT, 15.2 and -20.5 s for PTT, and 1.03 and -0.57 for INR. Conclusion This study showed a clinically acceptable concordance between laboratory and immediate diagnosis for INR. Concordance for PT and PTT did not meet clinical requirements. For patients under oral anticoagulation therapy, patient INR diagnosis enabled optimisation of the treatment procedure when planning dental surgery. PMID:16316464
Kumar, K.R. Ashok; Sarvagna, Jagadesh; Gadde, Praveen; Chikkaboriah, Shwetha
Introduction Hemostasis is a fundamental management issue post-operatively in minor oral surgical procedures. To ensure safety and therapeutic efficacy in patients, under oral anti coagulant therapy, is complicated by necessity for frequent determination of prothrombin time or international normalised ratio. Aim The aim of the study was to determine whether early hemostasis achieved by using Hemcon Dental Dressing (HDD) will affect post-operative care and surgical healing outcome in minor oral surgical procedures. Materials and Methods A total of 30 patients, aged 18 years to 90 years, except those allergic to seafood, who consented to participate, were enrolled into this study. Patients were required to have two or more surgical sites so that they would have both surgical and control sites. All patients taking Oral Anticoagulation Therapy (OAT) were included for treatment in the study without altering the anticoagulant regimens. Institutional Review Board approval was obtained for the same. The collected data was subjected to statistical analysis using unpaired t-test. Results All HDD surgically treated sites achieved hemostasis in 1.49 minutes and control wounds in 4.06 minutes (p < 0.001). Post-operative pain at HDD treated sites (1.87,1.27 on 1st and 3rd day respectively) was significantly lower than the control sites (4.0,1.87 on 1st and 3rd day respectively) p-value (0.001, 0.001 respectively). HDD treated oral surgery wounds achieved statistically significant improved healing both at 1st and 3rd post-operative days (p <0.0001). Conclusion The HDD has been proven to be a clinically effective hemostatic dressing material that significantly shortens bleeding time following minor oral surgical procedures under local anaesthesia, including those patients taking OAT. Patients receiving the HDD had improved surgical wound healing as compared to controls. PMID:27790577
Kalabalik, Julie; Rattinger, Gail B; Sullivan, Jesse; Slugocki, Malgorzata; Carbone, Antonia; Rivkin, Anastasia
Atrial fibrillation is a commonly encountered arrhythmia associated with increased risk for thromboembolic events. Anticoagulation is necessary to decrease the risk of ischemic stroke. Traditionally, warfarin has been the only oral pharmacotherapeutic option for long-term anticoagulation in patients with nonvalvular atrial fibrillation (NVAF). Recently, non-vitamin K antagonist oral anticoagulants (NOAC), including dabigatran, rivaroxaban, apixaban, and edoxaban, have become available as alternatives for warfarin in the prevention of stroke in patients with NVAF. Recently published atrial fibrillation guidelines contain new recommendations for risk stratification tools in determining the need for anticoagulant therapy and incorporate NOAC pharmacotherapy options for stroke prevention in patients with NVAF. NOACs offer several advantages over warfarin, including the elimination of routine laboratory monitoring, fewer drug and food interactions, and rapid therapeutic onset and offset. However, the lack of antidote in the case of serious bleeding and lack of data for long-term use in patient populations at risk for bleeding is problematic. Older adults are at high risk for thromboembolic and bleeding events as a result of anticoagulation and require special consideration when selecting anticoagulant therapy. The risk of drug accumulation and bleeding is concerning in the presence of renal impairment. The objective of this review is to provide the clinician with an update on the use of NOACs for NVAF, focusing on older adults and patients with renal impairment in light of recently published atrial fibrillation guidelines. Available data on using NOACs in coronary artery stenting, cardioversion, and ablation are also reviewed.
Bliden, Kevin P; Chaudhary, Rahul; Mohammed, Nafees; Muresan, Adina A; Lopez-Espina, Carlos G; Cohen, Eli; Raviv, Gabriel; Doubleday, Marc; Zaman, Fowzia; Mathew, Blessy; Tantry, Udaya S; Gurbel, Paul A
Non vitamin K oral anticoagulants (NOACs) do not require regular monitoring but information about their pharmacodynamic effect may be importantin situations like trauma, stroke oremergent surgery. Currently, no standardized point-of-care test is available to evaluate the anticoagulant effects of NOACs. We evaluated the anticoagulant effect of NOACs with the next generation point-of-care TEG assay (TEG® 6S) based on a fully-automated thrombelastography system. We used two TEG® 6S assays, the DTI assay and Anti-Factor Xa (AFXa) assay, to detect anticoagulant effects and classify NOACs. Blood from healthy volunteers (n = 26) was used to obtain a baseline reference range. Data derived from patients on factor Xa inhibitors (FXi) (rivaroxaban and apixaban) (n = 39), and direct thrombin inhibitors (DTIs) (dabigatran) (n = 25) were compared against the reference range for detection of drug effect and drug classification. TEG®6s R-time highly correlated to each NOAC. Presence of NOACs caused elongation of R-time on the AFXa assay compared to the reference range (4.3 ± 1.7 vs. 1.3 ± 0.3 min. for FXi, p < 0.001 and 3.5 ± 1.2 vs. 1.3 ± 0.3 min. for DTI, p < 0.001). R-time on the DTI assay was elongated only in presence of a DTI (3.4 ± 1.0 vs. 1.5 ± 0.2 min, p < 0.001). The cutoff for detection of a DTI effect was an R time of 1.9 min and for anti-Xa effect was 1.95 min. For detection of NOAC therapy, there was ≥92% sensitivity and ≥95% specificity. The automated TEG®6s NOAC assay may be an effective tool to identify an anticoagulant effect from NOAC therapy and facilitate care of patients with bleeding or at risk of bleeding in the event of needing emergency surgery.
Endoscopy in patients on antiplatelet or anticoagulant therapy, including direct oral anticoagulants: British Society of Gastroenterology (BSG) and European Society of Gastrointestinal Endoscopy (ESGE) guidelines.
Veitch, Andrew M; Vanbiervliet, Geoffroy; Gershlick, Anthony H; Boustiere, Christian; Baglin, Trevor P; Smith, Lesley-Ann; Radaelli, Franco; Knight, Evelyn; Gralnek, Ian M; Hassan, Cesare; Dumonceau, Jean-Marc
The risk of endoscopy in patients on antithrombotics depends on the risks of procedural haemorrhage vs. thrombosis due to discontinuation of therapy. P2Y12 receptor antagonists (clopidogrel, prasugrel, ticagrelor): For low-risk endoscopic procedures we recommend continuing P2Y12 receptor antagonists as single or dual antiplatelet therapy (low quality evidence, strong recommendation);For high-risk endoscopic procedures in patients at low thrombotic risk, we recommend discontinuing P2Y12 receptor antagonists five days before the procedure (moderate quality evidence, strong recommendation). In patients on dual antiplatelet therapy, we suggest continuing aspirin (low quality evidence, weak recommendation).For high-risk endoscopic procedures in patients at high thrombotic risk, we recommend continuing aspirin and liaising with a cardiologist about the risk/benefit of discontinuation of P2Y12 receptor antagonists (high quality evidence, strong recommendation). Warfarin: The advice for warfarin is fundamentally unchanged from BSG 2008 guidance. Direct Oral Anticoagulants (DOAC): For low-risk endoscopic procedures we suggest omitting the morning dose of DOAC on the day of the procedure (very low quality evidence, weak recommendation). For high-risk endoscopic procedures, we recommend that the last dose of DOAC be taken ≥ 48 hours before the procedure (very low quality evidence, strong recommendation). For patients on dabigatran with CrCl (or estimated glomerular filtration rate, eGFR) of 30 - 50 mL/min we recommend that the last dose of DOAC be taken 72 hours before the procedure (very low quality evidence, strong recommendation). In any patient with rapidly deteriorating renal function a haematologist should be consulted (low quality evidence, strong recommendation).
Endoscopy in patients on antiplatelet or anticoagulant therapy, including direct oral anticoagulants: British Society of Gastroenterology (BSG) and European Society of Gastrointestinal Endoscopy (ESGE) guidelines
Veitch, Andrew M; Vanbiervliet, Geoffroy; Gershlick, Anthony H; Boustiere, Christian; Baglin, Trevor P; Smith, Lesley-Ann; Radaelli, Franco; Knight, Evelyn; Gralnek, Ian M; Hassan, Cesare; Dumonceau, Jean-Marc
The risk of endoscopy in patients on antithrombotics depends on the risks of procedural haemorrhage versus thrombosis due to discontinuation of therapy. P2Y12 receptor antagonists (clopidogrel, prasugrel, ticagrelor) For low-risk endoscopic procedures we recommend continuing P2Y12 receptor antagonists as single or dual antiplatelet therapy (low quality evidence, strong recommendation); For high-risk endoscopic procedures in patients at low thrombotic risk, we recommend discontinuing P2Y12 receptor antagonists five days before the procedure (moderate quality evidence, strong recommendation). In patients on dual antiplatelet therapy, we suggest continuing aspirin (low quality evidence, weak recommendation). For high-risk endoscopic procedures in patients at high thrombotic risk, we recommend continuing aspirin and liaising with a cardiologist about the risk/benefit of discontinuation of P2Y12 receptor antagonists (high quality evidence, strong recommendation). Warfarin The advice for warfarin is fundamentally unchanged from British Society of Gastroenterology (BSG) 2008 guidance. Direct Oral Anticoagulants (DOAC) For low-risk endoscopic procedures we suggest omitting the morning dose of DOAC on the day of the procedure (very low quality evidence, weak recommendation); For high-risk endoscopic procedures, we recommend that the last dose of DOAC be taken ≥48 h before the procedure (very low quality evidence, strong recommendation). For patients on dabigatran with CrCl (or estimated glomerular filtration rate, eGFR) of 30–50 mL/min we recommend that the last dose of DOAC be taken 72 h before the procedure (very low quality evidence, strong recommendation). In any patient with rapidly deteriorating renal function a haematologist should be consulted (low quality evidence, strong recommendation). PMID:26873868
Kostewicz, Edmund S; Aarons, Leon; Bergstrand, Martin; Bolger, Michael B; Galetin, Aleksandra; Hatley, Oliver; Jamei, Masoud; Lloyd, Richard; Pepin, Xavier; Rostami-Hodjegan, Amin; Sjögren, Erik; Tannergren, Christer; Turner, David B; Wagner, Christian; Weitschies, Werner; Dressman, Jennifer
Drug absorption from the gastrointestinal (GI) tract is a highly complex process dependent upon numerous factors including the physicochemical properties of the drug, characteristics of the formulation and interplay with the underlying physiological properties of the GI tract. The ability to accurately predict oral drug absorption during drug product development is becoming more relevant given the current challenges facing the pharmaceutical industry. Physiologically-based pharmacokinetic (PBPK) modeling provides an approach that enables the plasma concentration-time profiles to be predicted from preclinical in vitro and in vivo data and can thus provide a valuable resource to support decisions at various stages of the drug development process. Whilst there have been quite a few successes with PBPK models identifying key issues in the development of new drugs in vivo, there are still many aspects that need to be addressed in order to maximize the utility of the PBPK models to predict drug absorption, including improving our understanding of conditions in the lower small intestine and colon, taking the influence of disease on GI physiology into account and further exploring the reasons behind population variability. Importantly, there is also a need to create more appropriate in vitro models for testing dosage form performance and to streamline data input from these into the PBPK models. As part of the Oral Biopharmaceutical Tools (OrBiTo) project, this review provides a summary of the current status of PBPK models available. The current challenges in PBPK set-ups for oral drug absorption including the composition of GI luminal contents, transit and hydrodynamics, permeability and intestinal wall metabolism are discussed in detail. Further, the challenges regarding the appropriate integration of results from in vitro models, such as consideration of appropriate integration/estimation of solubility and the complexity of the in vitro release and precipitation data
DI BENEDETTO, PAOLO; VETRUGNO, LUIGI; DE FRANCESCHI, DANIA; GISONNI, RENATO; CAUSERO, ARALDO; ROCCA, GIORGIO DELLA
Purpose the main purpose of our study was to compare patient compliance with the orally administered new oral anticoagulants (NOCs) dabigatran and rivaroxaban compared with subcutaneously injected fondaparinux after major orthopaedic surgery, and to assess patient preference for the oral vs subcutaneous administration route. Methods prophylactic antithrombotic drug therapy with dabigatran (group D; GD, n=32 patients), rivaroxaban (group R; GR, n=38 patients) or fondaparinux (group F; GF, n=30 patients), to prevent deep vein thrombosis, was started immediately after surgery in 100 patients submitted to total hip arthroplasty. Results the patients had a mean age of 68.7±11 years and 62% were female. In GD, 87.5% of patients indicated that they preferred oral intake of medications to subcutaneous injection (12.5%). In GR, 84.2% declared a preference for oral administration over subcutaneous injection (15.8%). In GF, a surprisingly high proportion of patients (73.3%; p < 0.001) declared that they preferred subcutaneous administration of medications over the oral route (26.7%). Overall, the rate of compliance with antithrombotic drug therapy was very high, at 99%. Conclusions intake of the NOAs dabigatran and rivaroxaban following hospital discharge is entirely the responsibility of the patient; a high level of patient compliance with these drugs must therefore be demonstrated in order for them to become well accepted within the medical community. The results of this study showed a very high level of compliance both with orally and subcutaneously administered drugs. Level of evidence Level I, randomized clinical study. PMID:28217657
Kline, Jeffrey A; Kahler, Zachary P; Beam, Daren M
Background Oral monotherapy anticoagulation has facilitated home treatment of venous thromboembolism (VTE) in outpatients. Objectives The aim of this study was to measure efficacy, safety, as well as patient and physician perceptions produced by a protocol that selected VTE patients as low-risk patients by the Hestia criteria, and initiated home anticoagulation with an oral factor Xa antagonist. Methods Patients were administered the Venous Insufficiency Epidemiological and Economic Study Quality of life/Symptoms questionnaire [VEINEs QoL/Sym] and the physical component summary [PCS] from the Rand 36-Item Short Form Health Survey [SF36]). The primary outcomes were VTE recurrence and hemorrhage at 30 days. Secondary outcomes compared psychometric test scores between patients with deep vein thrombosis (DVT) to those with pulmonary embolism (PE). Patient perceptions were abstracted from written comments and physician perceptions specific to PE outpatient treatment obtained from structured survey. Results From April 2013 to September 2015, 253 patients were treated, including 67 with PE. Within 30 days, 2/253 patients had recurrent DVT and 2/253 had major hemorrhage; all four had DVT at enrollment. The initial PCS scores did not differ between DVT and PE patients (37.2±13.9 and 38.0±12.1, respectively) and both DVT and PE patients had similar improvement over the treatment period (42.2±12.9 and 43.4±12.7, respectively), consistent with prior literature. The most common adverse event was menorrhagia, present in 15% of women. Themes from patient-written responses reflected satisfaction with increased autonomy. Physicians’ (N=116) before-to-after protocol comfort level with home treatment of PE increased 48% on visual analog scale. Conclusion Hestia-negative VTE patients treated with oral monotherapy at home had low rates of VTE recurrence and bleeding, as well as quality of life measurements similar to prior reports. PMID:27143861
Larsen, Torben Bjerregaard; Skjøth, Flemming; Grove, Erik Lerkevang; Nielsen, Peter Brønnum; Christensen, Thomas Decker
Patient-self-management (PSM) of oral anticoagulant therapy (OAT) with vitamin K antagonists for venous thromboembolism (VTE) has demonstrated efficacy in randomised, controlled trials. The aim of this study was to evaluate the effectiveness of PSM of OAT in everyday clinical practice. Prospectively registered patient data were obtained from databases at two hospitals, and cross-linkage with national patient registries provided detailed information on comorbidities and events. Patients with VTE performing PSM affiliated to major PSM centres were included as cases (N=444). A control group of patients on conventional treatment was propensity score selected in a ratio of 1:5 (N=2220) within matched groups. The effectiveness and safety was estimated using recurrent VTE, major bleeding events and all-cause death as outcomes. We found a lower rate of recurrent VTE among PSM patients compared to the control group with a hazard ratio (HR) of 0.63; 95 % confidence interval (CI) 0.42-0.95, whereas no difference was seen with bleeding (HR: 0.95; 95 % CI 0.44-2.02). The risk of all-cause death was lower for PSM patients (HR: 0.41; 95 % CI 0.21-0.81). A net clinical benefit analysis sums the effect on recurrent VTE and bleeding up to a weighted rate difference of 0.86 (95 % CI 0.00-1.72) in favour of PSM. In conclusion, PSM of anticoagulant treatment was associated with a statistically significant lower rate of recurrent VTE and all-cause death compared to patients on conventionally managed anticoagulant treatment. All major thromboembolic outcomes were less frequent among self-managed patients, whereas bleedings were observed with similar frequency.
Agarwal, M B; Verma, Subhash; Mahapatra, Manoranjan; Tripathi, A K; Bhave, Abhay; Deshpande, Anand; Vora, Amit; Dalal, Jamshed J; Shah, A B; Bichu, S
With the evaluation and approval of newer oral anticoagulants such as the factor IIa inhibitor, dabigatran etexilate and the factor Xa inhibitors, rivaroxaban and apixaban, strategies for stroke prevention in atrial fibrillation need a thorough re-evaluation of current options. Clinicians are naturally excited about the imminent introduction of these newer drugs that do not need international normalized ratio (INR) monitoring, besides having no drug-food and minimal drug-drug interactions. However, as with all new drugs, it is always prudent to use these judiciously so that they stay in our therapeutic armamentarium for a long time. More than 56 years after the introduction of warfarin we now have three drugs, viz., dabigatran 150 mg bid, rivaroxaban 20 mg od, and apixaban 5 mg bid which were effective in comparison with warfarin in reducing the risk of stroke and bleeding in the landmark trials, RE-LY, ROCKET-AF, and ARISTOTLE respectively. There is a thin dividing line between physiological hemostasis and pathological thrombosis. Routine INR monitoring may not be required but in special situations, such as prior to major surgery, overdose, non-compliance or stroke while on the anticoagulant, one may wish to know whether there are any laboratory measures of efficacy or means of reversal of over anticoagulation. Similar questions may be raised about other situations such as renal dysfunction, cardioversion, ablation procedures, post-stenting, or switch to and from warfarin, heparin or LMWH? This document is an attempt to address these concerns based on available evidence and give physicians a perspective and practice guidelines on how best to use these agents, both old and new, for optimal patient outcomes, maximizing efficacy and minimizing risk.
Jaraiz, V; Rodriguez, C; San Andres, M D; Gonzalez, F; San Andres, M I
A disposition and bioequivalence study with a suxibuzone granulated and a suxibuzone paste oral formulation was performed in horses. Suxibuzone (SBZ) is a nonsteroidal anti-inflammatory drug, which was administered to horses (n = 6) at a dosage of 19 mg/kg bwt by the oral route (p.o.) in a two period cross-over design. Suxibuzone is very rapidly transformed into its main active metabolites, phenylbutazone (PBZ) and oxyphenbutazone (OPBZ). Therefore plasma and synovial fluid concentrations of SBZ, PBZ and OPBZ were simultaneously measured by a sensitive and specific high-performance liquid chromatographic method. The pharmacokinetic parameters were determined by noncompartmental analysis. Suxibuzone could not be detected in any plasma and synovial fluid samples (< 0.04 microgram/mL). Plasma PBZ and OPBZ concentrations were detected between 30 min and 72 h after granulate and paste administration. Mean plasma concentration of PBZ peaked at 5 h (34.5 +/- 6.7 micrograms/mL) and at 7 h (38.8 +/- 8.4 micrograms/mL), and mean area under the concentration-time curve (AUC0-->LOQ) was 608.0 +/- 162.2 micrograms.h/mL and 656.6 +/- 149.7 micrograms.h/mL after granulate and paste administration, respectively. Mean plasma concentration of OPBZ increased to 5-6.7 micrograms/mL, with the maximum concentration (Cmax) appearing between 9 and 12 h after administration of both formulations. The AUCs0-->LOQ for OPBZ were also similar (141.8 +/- 48.3 micrograms.h/mL granulate vs. 171.4 +/- 45.0 micrograms.h/mL paste). It was concluded that the suxibuzone products were bioequivalent with respect to PBZ. For OPBZ, the 95% confidence intervals of the pharmacokinetic parameters were within the acceptable range of 80-125%. The paste formulation provided greater bioavailability of PBZ and OPBZ.
Wang, Jie; Goyanes, Alvaro; Gaisford, Simon; Basit, Abdul W
The aim of this work was to evaluate the suitability of stereolithography (SLA) to fabricate drug-loaded tablets with modified-release characteristics. The SLA printer creates solid objects by using a laser beam to photopolymerise monomers. In this work polyethylene glycol diacrylate (PEGDA) was used as a monomer and diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide was used as a photo-initiator. 4-aminosalicylic acid (4-ASA) and paracetamol (acetaminophen) were selected as model drugs. Tablets were successfully printed and formulations with different properties were fabricated by adding polyethylene glycol 300 (PEG 300) to the printing solution. The loading of paracetamol and 4-ASA in the printed tablets was 5.69% and 5.40% respectively. In a realistic dynamic dissolution simulation of the gastrointestinal tract, drug release from the tablets was dependent on the composition of the formulations, but independent of dissolution pH. In conclusion SLA 3DP technology allows the manufacture of drug loaded tablets with specific extended-release profiles. In the future this technology could become a manufacturing technology for the elaboration of oral dosage forms, for industrial production or even for personalised dose.
Smart, John D; Dunkley, Sian; Tsibouklis, John; Young, Simon
There is a requirement for the development of oral dosage forms that are adhesive and allow extended oesophageal residence time for localised therapies, or are non-adhesive for ease of swallowing. This study provides an initial assessment of the in vitro oesophageal retention characteristics of several widely utilised pharmaceutical coating materials. To this end, a previously described apparatus has been used to measure the force required to pull a coated disc-shaped model tablet across a section of excised oesophageal tissue. Of the materials tested, the well-studied mucoadhesive polymer sodium alginate was found to be associated with significant oesophageal adhesion properties that was capable of 'self-repairing'. Hydroxypropylmethylcellulose exhibited less pronounced bioadhesive behaviour and blending this with plasticiser or with low molecular weight polymers and surfactants did not significantly affect this. Low molecular weight water soluble polymers, were found to behave similarly to the uncoated glass control disc. Polysorbates exhibited bioadhesion behaviour that was majorly influenced by the nature of the surfactant. The insoluble polymer ethylcellulose, and the relatively lipophilic surfactant sorbitan monooleate were seen to move more readily than the uncoated disc, suggesting that these may have a role as 'easy-to-swallow' coatings.
Dressman, Jennifer B; Nair, Anita; Abrahamsson, Bertil; Barends, Dirk M; Groot, D W; Kopp, Sabine; Langguth, Peter; Polli, James E; Shah, Vinod P; Zimmer, Markus
A biowaiver monograph for acetylsalicylic acid (ASA) is presented. Literature and experimental data indicate that ASA is a highly soluble and highly permeable drug, leading to assignment of this active pharmaceutical ingredient (API) to Class I of the Biopharmaceutics Classification System (BCS). Limited bioequivalence (BE) studies reported in the literature indicate that products that have been tested are bioequivalent. Most of the excipients used in products with a marketing authorization in Europe are not considered to have an impact on gastrointestinal motility or permeability. Furthermore, ASA has a wide therapeutic index. Thus, the risks to the patient that might occur if a nonbioequivalent product were to be incorrectly deemed bioequivalent according to the biowaiver procedure appear to be minimal. As a result, the BCS-based biowaiver procedure can be recommended for approval of new formulations of solid oral dosage forms containing ASA as the only API, including both multisource and reformulated products, under the following conditions: (1) excipients are chosen from those used in ASA products already registered in International Conference on Harmonization and associated countries and (2) the dissolution profiles of the test and the comparator products comply with the BE guidance.
Strauch, S; Jantratid, E; Dressman, J B; Junginger, H E; Kopp, S; Midha, K K; Shah, V P; Stavchansky, S; Barends, D M
Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate release solid oral dosage forms containing mefloquine hydrochloride as the only active pharmaceutical ingredient (API) are reviewed. The solubility and permeability data of mefloquine hydrochloride as well as its therapeutic use and therapeutic index, its pharmacokinetic properties, data related to the possibility of excipient interactions and reported BE/bioavailability studies were taken into consideration. Mefloquine hydrochloride is not a highly soluble API. Since no data on permeability are available, it cannot be classified according to the Biopharmaceutics Classification System with certainty. Additionally, several studies in the literature failed to demonstrate BE of existing products. For these reasons, the biowaiver cannot be justified for the approval of new multisource drug products containing mefloquine hydrochloride. However, scale-up and postapproval changes (HHS-FDA SUPAC) levels 1 and 2 and most EU type I variations may be approvable without in vivo BE, using the dissolution tests described in these regulatory documents.
Leane, Michael; Pitt, Kendal; Reynolds, Gavin
This paper proposes the development of a drug product Manufacturing Classification System (MCS) based on processing route. It summarizes conclusions from a dedicated APS conference and subsequent discussion within APS focus groups and the MCS working party. The MCS is intended as a tool for pharmaceutical scientists to rank the feasibility of different processing routes for the manufacture of oral solid dosage forms, based on selected properties of the API and the needs of the formulation. It has many applications in pharmaceutical development, in particular, it will provide a common understanding of risk by defining what the "right particles" are, enable the selection of the best process, and aid subsequent transfer to manufacturing. The ultimate aim is one of prediction of product developability and processability based upon previous experience. This paper is intended to stimulate contribution from a broad range of stakeholders to develop the MCS concept further and apply it to practice. In particular, opinions are sought on what API properties are important when selecting or modifying materials to enable an efficient and robust pharmaceutical manufacturing process. Feedback can be given by replying to our dedicated e-mail address (email@example.com); completing the survey on our LinkedIn site; or by attending one of our planned conference roundtable sessions.
Kuribayashi, Ryosuke; Takishita, Tomoko; Mikami, Kenichi
Bioequivalence (BE) studies are used to infer the therapeutic equivalence of generic drug products to original drug products throughout the world. In BE studies, bioavailability (BA) should be compared between the original and generic drug products, with BA defined as the rate and extent of absorption of active pharmaceutical ingredients or active metabolites from a product into the systemic circulation. For most of BE studies conducted during generic drug development, BA comparisons are performed in single-dose studies. In Japan, the revised "Guideline for Bioequivalence Studies of Generic Products" was made available in 2012 by the Ministry of Health, Labour, and Welfare, and generic drug development is currently conducted based on this guideline. Similarly, the U.S. Food and Drug Administration and European Medicines Agency have published guidance and guideline on generic drug development. This article introduces the guideline on Japanese BE studies for oral solid dosage forms and the dissolution tests for the similarity and equivalence evaluation between the original and generic drug products. Additionally, we discuss some of the similarities and differences in guideline between Japan, the United States, and the European Union.
Imberti, Davide; Benedetti, Raffaella; Ageno, Walter
Venous thromboembolism (VTE) is a common potentially life-threatening complication in acutely ill medical patients; over 70 % of the fatal episodes of pulmonary embolism during hospitalization occur in non-surgical patients. In the absence of thromboprophylaxis, the incidence of venographically detected deep vein thrombosis is about 15 % in medical patients. Several trials and meta-analyses have clearly demonstrated the prophylactic role of unfractionated heparin, low molecular weight heparin and fondaparinux. Although over the past few years the knowledge of epidemiology, clinical features and prophylaxis in medical patients has significantly improved, there remain a number of controversial areas that require further investigation. Newer VTE risk assessment models have been proposed to select high risk hospitalized medical patients, but they still require external validation; scarce data are available to stratify patients to identify their individual bleeding risk. The optimal duration of thromboprophylaxis in medical patients is still a matter of debate; currently, extended prophylaxis after discharge is not recommended, but it may be required for subgroup of patients with persistently high VTE risk and a negligible risk of bleeding. Based on the results of recent studies, the new oral anticoagulants appear to have a very limited role, if any. However, a better risk stratification of patients who have a persistently increased risk of VTE is warranted to improve the risk to benefit profile of any anticoagulant drug to be used in this setting.
Borris, Lars C
Extended thromboprophylaxis is vital in patients undergoing total hip arthroplasty (THA) because of the prolonged risk of venous thromboembolism (VTE). Despite evidence that extended prophylaxis can reduce the incidence of symptomatic VTE in this high-risk patient population and the evidence-based guideline recommendations, a large proportion of patients still do not receive an adequate duration of thromboprophylaxis. This is partly due to the limitations of conventional anticoagulants, such as the subcutaneous route of administration or the requirement for routine coagulation monitoring and dose adjustment. New oral anticoagulants (such as the direct thrombin inhibitor dabigatran etexilate and the Factor Xa inhibitor rivaroxaban) could address the current unmet need. Phase III clinical studies in VTE prevention in patients undergoing THA and total knee arthroplasty (TKA) showed that dabigatran etexilate was non-inferior to the EU regimen of enoxaparin, but did not achieve non-inferiority to the US regimen of enoxaparin. In contrast, rivaroxaban demonstrated superiority to both enoxaparin regimens for the prevention of VTE after THA and TKA, without a significant increase in major bleeding rates. Their convenient, once-daily, fixed dosing, with no need for routine coagulation monitoring, could facilitate adherence to evidence-based guideline recommendations of extended thromboprophylaxis after THA.
Background New oral anticoagulant (NOAC) drugs are known to influence the results of some routine hemostasis tests. Further data are needed to enable routine assessment of the effects of NOAC on clotting parameters in some special circumstances. Methods Following administration of rivaroxaban to patients, at the likely peak and trough activity times, we assessed the effects on prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT), and clotting time using Russell’s viper venom, and in the presence of phospholipids and calcium reagent available as DVVreagent® and DVVconfirm®. The data were used to determine an adequate NOAC plasma level based on anticoagulant activities expressed as a ratio (patients/normal, R-C). Results DVVconfirm as R-C could be rapidly performed, and the results were reasonably sensitive for rivaroxaban and probably for other FX inhibitors. This assay is not influenced by lupus anticoagulant and heparin, does not require purified NOAC as control, and will measure whole-plasma clotting activity. Conclusions We propose a cut-off R-C value of 4.52 ± 0.33 for safety, but clinical studies are needed to establish whether this cut-off is useful for identifying patients at increased risk of hemorrhage or exhibiting low anticoagulation effect. It also seems possible that normal R-C could indicate an absence of anticoagulant activity when rivaroxaban is discontinued due to episodes of uncontrolled bleeding during anticoagulation or for emergency surgery. PMID:24656069
van Gorp, Rick H.; Schurgers, Leon J.
Vitamin K-antagonists (VKA) are the most widely used anticoagulant drugs to treat patients at risk of arterial and venous thrombosis for the past 50 years. Due to unfavorable pharmacokinetics VKA have a small therapeutic window, require frequent monitoring, and are susceptible to drug and nutritional interactions. Additionally, the effect of VKA is not limited to coagulation, but affects all vitamin K-dependent proteins. As a consequence, VKA have detrimental side effects by enhancing medial and intimal calcification. These limitations stimulated the development of alternative anticoagulant drugs, resulting in direct oral anticoagulant (DOAC) drugs, which specifically target coagulation factor Xa and thrombin. DOACs also display non-hemostatic vascular effects via protease-activated receptors (PARs). As atherosclerosis is characterized by a hypercoagulable state indicating the involvement of activated coagulation factors in the genesis of atherosclerosis, anticoagulation could have beneficial effects on atherosclerosis. Additionally, accumulating evidence demonstrates vascular benefit from high vitamin K intake. This review gives an update on oral anticoagulant treatment on the vasculature with a special focus on calcification and vitamin K interaction. PMID:26593943
Harter, Katherine; Levine, Michael; Henderson, Sean O.
Historically, most patients who required parenteral anticoagulation received heparin, whereas those patients requiring oral anticoagulation received warfarin. Due to the narrow therapeutic index and need for frequent laboratory monitoring associated with warfarin, there has been a desire to develop newer, more effective anticoagulants. Consequently, in recent years many novel anticoagulants have been developed. The emergency physician may institute anticoagulation therapy in the short term (e.g. heparin) for a patient being admitted, or may start a novel anticoagulation for a patient being discharged. Similarly, a patient on a novel anticoagulant may present to the emergency department due to a hemorrhagic complication. Consequently, the emergency physician should be familiar with the newer and older anticoagulants. This review emphasizes the indication, mechanism of action, adverse effects, and potential reversal strategies for various anticoagulants that the emergency physician will likely encounter. PMID:25671002
Vogel, T; Lang, P-O; Kaltenbach, G; Karcher, P
The growing use of direct oral anticoagulants, in particular among older subjects, raises questions about the limits of the evidence-based medicine. The phase III studies that have validated the efficacy and the safety profile of these molecules (dabigatran, rivaroxaban, apixaban, edoxaban) in their both indications, the venous thromboembolic disease and the non-valvular atrial fibrillation raise concerns in four major fields: the financial support of pharmaceutical companies, the links of interest for many authors with the industry, the study design (exclusively non-inferiority studies), and the poor representativeness of the older subjects included. All these points are discussed, using data of sub-groups studies, post-marketing studies and recent meta-analysis. The lack of data for the very old subjects, with frailty or comorbidities, remains the main concern from these phase III studies.
Rodríguez-Bernal, Clara L; Hurtado, Isabel; García-Sempere, Aníbal; Peiró, Salvador; Sanfélix-Gimeno, Gabriel
Objective: Little is known about initial prescription of currently used oral anticoagulants (OAC), and correlated characteristics in real-world practice. We aimed to assess patterns of initiation of Vitamin K antagonists (VKA) and non-VKA oral anticoagulants (NOAC) in naive patients with non-valvular atrial fibrillation and the factors associated with starting treatment with NOAC. Methods: Population-based retrospective cohort study of all patients with NVAF who had a first prescription of OAC from November 2011 to February 2014 in the Valencia region, Spain (n = 21,881). Temporal trends of OAC initiation are described for the whole population and by type of OAC and therapeutic agent. Factors associated with starting treatment with NOAC (vs. VKA) were identified using logistic multivariate regression models. Results: Among the patients initiating OAC, 25% started with NOAC 2 years after market release. Regarding temporal trends, prescription of NOAC doubled during the study period. VKA prescription also increased (by around 13%), resulting in a 30% rise in total treatment initiation with OAC during 2011-2014. NOAC initiation (vs. VKA) was associated with a lower baseline risk of thromboembolism and higher income. Conclusions: In this Spanish population-based cohort, initiation of OAC therapy saw a rapid increase, mainly but not exclusively, due to a two-fold rise in the use of NOAC. Initiation with NOAC was associated with a lower baseline risk of thromboembolism and higher income, which opposes the indications of NOAC use and reflects disparities in care. Inadequate prescription patterns might threaten the effectiveness and safety of these therapies, thus monitoring OAC prescription is necessary and should be setting-specific.
Halvorsen, Sigrun; Ghanima, Waleed; Fride Tvete, Ingunn; Hoxmark, Cecilie; Falck, Pål; Solli, Oddvar; Jonasson, Christian
Aims We aimed to evaluate bleeding risk in clinical practice in patients with atrial fibrillation (AF) being prescribed dabigatran, rivaroxaban, or apixaban compared with warfarin. Methods Using nationwide registries (Norwegian Patient Registry and Norwegian Prescription Database), we identified AF patients with a first prescription of oral anticoagulants between January 2013 and June 2015. Patients were followed until discontinuation or switching of oral anticoagulants, death, or end of follow-up. The primary endpoint was major or clinically relevant non-major (CRNM) bleeding. Results In total 32 675 AF patients were identified (58% men, median age 74 years): 11 427 patients used warfarin, 7925 dabigatran, 6817 rivaroxaban, and 6506 apixaban. After a median follow-up of 173 days (25th, 75th percentile 84, 340), 2081 (6.37%) patients experienced a first major or CRNM bleeding. Using a Cox proportional hazard model adjusting for baseline characteristics, use of apixaban [hazard ratio (HR) 0.70, 95% confidence interval (CI) 0.61–0.80, P < 0.001] and dabigatran (HR 0.74, 95% CI 0.66–0.84, P < 0.001) were associated with a lower risk of major or CRNM bleeding compared with warfarin whereas use of rivaroxaban was not (HR: 1.05, 95% CI 0.94–1.17, P = 0.400). Use of dabigatran and rivaroxaban were associated with higher risk of gastrointestinal bleeding, whereas use of apixaban and dabigatran were associated with lower risk of intracranial bleeding, compared with warfarin. Conclusion In this nationwide cohort study in AF patients, apixaban and dabigatran were associated with a lower risk of major or CRNM bleeding compared with warfarin. The risk of gastrointestinal bleeding was higher with rivaroxaban and dabigatran compared with warfarin. PMID:27680880
Rubboli, A; Faxon, D P; Juhani Airaksinen, K E; Schlitt, A; Marín, F; Bhatt, D L; Lip, G Y H
Even 10 years after the first appearance in the literature of articles reporting on the management of patients on oral anticoagulation (OAC) undergoing percutaneous coronary intervention with stent (PCI-S), this issue is still controversial. Nonetheless, some guidance for the everyday management of this patient subset, accounting for about 5-8 % of all patients referred for PCI-S, has been developed. In general, a period of triple therapy (TT) of OAC, with either vitamin K-antagonists (VKA) or non-vitamin K-antagonist oral anticoagulants (NOAC), aspirin, and clopidogrel is warranted, followed by the combination of OAC, and a single antiplatelet agent for up to 12 months, and then OAC alone. The duration of the initial period of TT is dependent on the individual risk of thromboembolism, and bleeding, as well as the clinical context in which PCI-S is performed (elective vs acute coronary syndrome), and the type of stent implanted (bare-metal vs drug-eluting). In this article, we aim to provide a comprehensive, at-a-glance, overview of the management strategies, which are currently suggested for the peri-procedural, medium-term, and long-term periods following PCI-S in OAC patients. While acknowledging that most of the evidence has been obtained from patients on OAC because of atrial fibrillation, and with warfarin being the most frequently used VKA, we refer in this overview to the whole population of OAC patients undergoing PCI-S. We refer to the whole population of patients on OAC undergoing PCI-S also when OAC is carried out with NOAC rather than VKA, pointing out, when appropriate, the particular management issues.
Rodríguez-Bernal, Clara L.; Hurtado, Isabel; García-Sempere, Aníbal; Peiró, Salvador; Sanfélix-Gimeno, Gabriel
Objective: Little is known about initial prescription of currently used oral anticoagulants (OAC), and correlated characteristics in real-world practice. We aimed to assess patterns of initiation of Vitamin K antagonists (VKA) and non-VKA oral anticoagulants (NOAC) in naive patients with non-valvular atrial fibrillation and the factors associated with starting treatment with NOAC. Methods: Population-based retrospective cohort study of all patients with NVAF who had a first prescription of OAC from November 2011 to February 2014 in the Valencia region, Spain (n = 21,881). Temporal trends of OAC initiation are described for the whole population and by type of OAC and therapeutic agent. Factors associated with starting treatment with NOAC (vs. VKA) were identified using logistic multivariate regression models. Results: Among the patients initiating OAC, 25% started with NOAC 2 years after market release. Regarding temporal trends, prescription of NOAC doubled during the study period. VKA prescription also increased (by around 13%), resulting in a 30% rise in total treatment initiation with OAC during 2011–2014. NOAC initiation (vs. VKA) was associated with a lower baseline risk of thromboembolism and higher income. Conclusions: In this Spanish population-based cohort, initiation of OAC therapy saw a rapid increase, mainly but not exclusively, due to a two-fold rise in the use of NOAC. Initiation with NOAC was associated with a lower baseline risk of thromboembolism and higher income, which opposes the indications of NOAC use and reflects disparities in care. Inadequate prescription patterns might threaten the effectiveness and safety of these therapies, thus monitoring OAC prescription is necessary and should be setting-specific. PMID:28261098
Macquart de Terline, Diane; Hejblum, Gilles; Fernandez, Christine; Cohen, Ariel; Antignac, Marie
Background Oral anticoagulation therapy is increasingly used for the prevention and treatment of thromboembolic complications in various clinical situations. Nowadays, education programs for patients treated with anticoagulants constitute an integrated component of their management. However, such programs are usually based on the healthcare providers’ perceptions of what patients should know, rather than on patients’ preferences. Objective To investigate patients’ viewpoints on educational needs and preferred modalities of information delivery. Methods We conducted an observational study based on a self-administered questionnaire. To explore several profiles of patients, the study was designed for enrolling patients in two settings: during outpatient consultations in a cardiology department (Saint Antoine Hospital, Paris, France) and in community pharmacies throughout France. Results Of the 371 patients who completed the questionnaire, 187 (50.4%) were recruited during an outpatient consultation and 184 (49.6%) were recruited in community pharmacies. 84.1% of patients were receiving a vitamin K antagonist and 15.6% a direct oral anticoagulant. Patients ranked 16 of 21 (76.2%) questionnaire items on information about their treatment as important or essential; information on adverse effects of treatment was the highest ranked domain (mean score 2.38, 95% CI 2.30–2.46). Pharmacists (1.69, 1.58–1.80), nurses (1.05, 0.95–1.16), and patient associations (0.36, 0.29–0.44), along with group sessions (0.85, 0.75–0.95), the internet (0.77, 0.67–0.88), and delivery of material at the patient’s home (1.26, 1.14–1.38), were ranked poorly in terms of delivering educational material. Conclusion This study revealed substantial discrepancies between patient preferences and current educational programs. These findings should be useful for tailoring future educational programs that are better adapted to patients, with a potential associated enhancement of their
Winkle, Roger A.; Mead, R. Hardwin; Engel, Gregory; Kong, Melissa H.; Patrawala, Rob A.
Aims Atrial fibrillation ablation requires peri-procedural oral anticoagulation (OAC) to prevent thromboembolic events. There are several options for OAC. We evaluate peri-procedural AF ablation complications using a variety of peri-procedural OACs. Methods and results We examined peri-procedural OAC and groin, bleeding, and thromboembolic complications for 2334 consecutive AF ablations using open irrigated-tip radiofrequency (RF) catheters. Pre-ablation OAC was warfarin in 1113 (47.7%), dabigatran 426 (18.3%), rivaroxaban 187 (8.0%), aspirin 472 (20.2%), and none 136 (5.8%). Oral anticoagulation was always interrupted and intraprocedural anticoagulation was unfractionated heparin (activated clotting time, ACT = 237 ± 26 s). Pre- and post-OAC drugs were the same for 1591 (68.2%) and were different for 743 (31.8%). Following ablation, 693 (29.7%) were treated with dabigatran and 291 (12.5%) were treated with rivaroxaban. There were no problems changing from one OAC pre-ablation to another post-ablation. Complications included 12 (0.51%) pericardial tamponades [no differences for dabigatran (P = 0.457) or rivaroxaban (P = 0.163) compared with warfarin], 12 (0.51%) groin complications [no differences for rivaroxaban (P = 0.709) and fewer for dabigatran (P = 0.041) compared with warfarin]. Only 5 of 2334 (0.21%) required blood transfusions. There were two strokes (0.086%) and no transient ischaemic attacks (TIAs) in the first 48 h post-ablation. Three additional strokes (0.13%), and two TIAs (0.086%) occurred from 48 h to 30 days. Only one stroke had a residual deficit. Compared with warfarin, the neurologic event rate was not different for dabigatran (P = 0.684) or rivaroxaban (P = 0.612). Conclusion Using interrupted OAC, low target intraprocedural ACT, and irrigated-tip RF, the rate of peri-procedural groin, haemorrhagic, and thromboembolic complications was extremely low. There were only minimal differences between OACs. Low-risk patients may remain on aspirin
[Management of major bleeding complications and emergency surgery in patients on long-term treatment with direct oral anticoagulants, thrombin or factor-Xa inhibitors. Proposals of the Working Group on Perioperative Haemostasis (GIHP) - March 2013].
Pernod, G; Albaladejo, P; Godier, A; Samama, C M; Susen, S; Gruel, Y; Blais, N; Fontana, P; Cohen, A; Llau, J V; Rosencher, N; Schved, J F; de Maistre, E; Samama, M M; Mismetti, P; Sié, P
New direct oral anticoagulants (NOAC), inhibitors of factor IIa or Xa, are expected to be widely used for the treatment of venous thromboembolic disease, or in case of atrial fibrillation. Such anticoagulant treatments are known to be associated with haemorrhagic complications. Moreover, it is likely that such patients on long-term treatment with NOAC will be exposed to emergency surgery or invasive procedures. Due to the present lack of experience in such conditions, we cannot make recommendations, but only propose management for optimal safety as regards the risk of bleeding in such emergency conditions. In this article, only dabigatran and rivaroxaban were discussed. For emergency surgery at risk of bleeding, we propose to dose the plasmatic concentration of drug. Levels inferior or equal to 30ng/mL for both dabigatran and rivaroxaban, should enable the realization of a high bleeding risk surgery. For higher concentration, it was proposed to postpone surgery by monitoring the evolution of the drug concentration. Action is then defined by the kind of NOAC and its concentration. If the dosage of the drug is not immediately available, proposals only based on the usual tests, PT and aPTT, also are presented. However, these tests do not really assess drug concentration or bleeding risk. In case of severe haemorrhage in a critical organ, it is proposed to reduce the effect of anticoagulant therapy using a nonspecific procoagulant drug (activated prothrombin concentrate, FEIBA, 30-50U/kg, or non-activated 4-factors prothrombin concentrates 50U/kg). For any other type of severe haemorrhage, the administration of such a procoagulant drug, potentially thrombogenic in these patients, will be discussed regarding concentration of NACO and possibilities for mechanical haemostasis.
Hess, Paul L; Mirro, Michael J; Diener, Hans-Christoph; Eikelboom, John W; Al-Khatib, Sana M; Hylek, Elaine M; Bosworth, Hayden B; Gersh, Bernard J; Singer, Daniel E; Flaker, Greg; Mega, Jessica L; Peterson, Eric D; Rumsfeld, John S; Steinberg, Benjamin A; Kakkar, Ajay K; Califf, Robert M; Granger, Christopher B
Approximately half of patients with atrial fibrillation and with risk factors for stroke are not treated with oral anticoagulation (OAC), whether it be with vitamin K antagonists (VKAs) or novel OACs (NOACs); and of those treated, many discontinue treatment. Leaders from academia, government, industry, and professional societies convened in Washington, DC, on December 3-4, 2012, to identify barriers to optimal OAC use and adherence and to generate potential solutions. Participants identified a broad range of barriers, including knowledge gaps about stroke risk and the relative risks and benefits of anticoagulant therapies; lack of awareness regarding the potential use of NOAC agents for VKA-unsuitable patients; lack of recognition of expanded eligibility for OAC; lack of availability of reversal agents and the difficulty of anticoagulant effect monitoring for the NOACs; concerns with the bleeding risk of anticoagulant therapy, especially with the NOACs and particularly in the setting of dual antiplatelet therapy; suboptimal time in therapeutic range for VKA; and costs and insurance coverage. Proposed solutions were to define reasons for oral anticoagulant underuse classified in ways that can guide intervention and improve use, to increase awareness of stroke risk as well as the benefits and risks of OAC use via educational initiatives and feedback mechanisms, to better define the role of VKA in the current therapeutic era including eligibility and ineligibility for different anticoagulant therapies, to identify NOAC reversal agents and monitoring strategies and make knowledge regarding their use publicly available, to minimize the duration of dual antiplatelet therapy and concomitant OAC where possible, to improve time in therapeutic range for VKA, to leverage observational data sets to refine understanding of OAC use and outcomes in general practice, and to better align health system incentives.
Rosca, I D; Vergnaud, J M
Oral dosage forms with controlled release exhibit various advantages over their immediate release counterparts, but they must be built adequately by dispersing the drug through the well-defined polymer matrix. This study is concerned with diffusion-controlled dosage forms to resolve the problems that appear: in vitro tests generally used for determining the kinetics of drug release do not take into account the nature of the drug. On the contrary, the plasma drug profiles obtained through in vivo tests strongly depend on the nature of the drug, through their typical pharmacokinetic parameters. Moreover, the effect of the stirring rate is difficult to evaluate. Following the demand from the FDA concerned with the in vitro/in vivo correlation, a numerical model was built so as to evaluate the plasma drug profile obtained with any drug delivered from a diffusion-controlled release dosage form. The results are expressed by connecting the half-life times of the drugs obtained either with bolus injection or with the dosage forms, for various values of the parameters of interest: the diffusivity of the matrix polymer and the size of the dosage form. Thus, these diagrams make it possible to promptly determine the characteristics of the dosage forms able to give the desired plasma drug profile for any drug. Of course, for each drug being defined by its pharmacokinetic parameters, the polymer matrix should be selected as a function of its diffusivity. Finally, the evaluation of the plasma drug profile is of effective help to determine quantitatively the effect of the intervariability of the patients as well as the effect of the patient's noncompliance.
Eldor, Amiram; Schwartz, Joseph
The efficacy of oral anticoagulants (OAC) in reducing the incidence of stroke in elderly patients with atrial fibrillation (AF) has been well documented. The intensity of OAC therapy and deviations in the prothrombin time (PT) are the strongest risk factor for bleeding complications in elderly patients. The aim of this study was to evaluate a more rigorous regulation of OAC by the use of a portable whole blood PT-monitor (CoaguChek) in elderly patients with AF (age 65-80 years). The study group consisted of 20 patients, of whom 17 were evaluable, which were trained to use to CoaguChek monitor and adjust their anticoagulant dose for 12 months. The control group, 20 patients matched for age, gender and the duration of OAC treatment, were tested in an anticoagulant clinic and their OAC dose was adjusted by a physician. To validate the PT-monitor results, the patients performed a total of 129 simultaneous venous blood PT tests at various time points. The correlation coefficient R(2) was 0.707 indicating the accuracy of the CoaguChek results. The self-managed patients perform more frequent measurements 46 +/- 8.9 vs. 15.7 +/- 3.1 PT tests per patient. They demonstrated a within the therapeutic range INR in 80.5% of the tests (95% confidence interval, 76.5-84.1%) as compared to 72.4% (95% confidence interval, 68.5-76.5%) in the control group (p = 0.057). The median value for all CoaguChek International Normalized Ratio (INR) recordings was within therapeutic range in the self-management group as well as in the control group. There were fewer INR results below or above the therapeutic range in the study group. None of the patients had hemorrhagic or thrombotic events during the study. Overall, the study group expressed high satisfaction from using the home monitor. We conclude that home PT monitoring and self-management of OAC are feasible in a motivated population of elderly patients with atrial fibrillation and are probably cost effective.
Ibrahim, Rami B; Skewes, Michelle D; Kuriakose, Philip
Simply providing anticoagulation therapy is not as straightforward of a solution in cancer patients who have concurrent thrombocytopenia owing to the increased risk of bleeding complications. Currently, few guidelines are in place to assist clinicians in safely managing thrombocytopenic cancer patients on anticoagulation. The purpose of this review is to critically examine the available body of biomedical literature surrounding anticoagulant use against the backdrop of cancer-related thrombocytopenia in adult patients. Available evidence for the use of parenteral anticoagulants (low molecular weight heparins, unfractionated heparin, pentasaccharides, and direct thrombin inhibitors) and oral anticoagulants (vitamin K antagonists and novel oral anticoagulants) in thrombocytopenic cancer patients is described. The review revealed many inconsistencies between reports on this topic, which made it difficult to draw firm conclusions as to, for example, the ideal well tolerated anticoagulant dose in thrombocytopenic cancer patients? Intriguingly, critical clinical information including (but not limited) patient platelet nadirs, platelet counts during bleeding episodes, and platelet transfusion support was absent from a not-so-insignificant number of publications. Despite these shortcomings, the review sets out to formulate recommendations on the management of anticoagulation, at prophylactic or treatment doses, in adult cancer patients who also have concurrent thrombocytopenia. It also enlists a call for the medical community, by mapping select clinical guideposts, for further research in this setting. With the inclusion of these criteria in future studies, only then formal recommendations on the ideal safe dosage of anticoagulants in cancer patients, based on solid evidence, are conceived.
Scholz, Patrik; Keck, Cornelia M
Many new developed drug actives are poorly soluble, therefore the need to increase the solubility of these actives arises. Nanosuspensions are fast and easy to produce, enhance the bioavailability of poorly soluble drugs and feature many beneficial characteristics. However, nanocrystals in suspension form are physically metastable. Furthermore, the application of nanocrystal suspensions has no retarding effects. To overcome long term stability issues and open up a variety of options for controlled release, nanocrystals can be converted into solid dosage forms by different methods with different outcomes and features. Transformation of nanosuspensions into solid dosage forms opens up manifold options for the development of dosage forms with tailor-made drug release profiles. This review focuses on nanocrystal properties, established and new production techniques, as well as state of the art techniques for transformation of nanosuspensions into solid dosage forms. Nanocrystal technology is already today used in several solid products and holds great potential for future uses.
Diener, Hans-Christoph; Aisenberg, James; Ansell, Jack; Atar, Dan; Breithardt, Günter; Eikelboom, John; Ezekowitz, Michael D; Granger, Christopher B; Halperin, Jonathan L; Hohnloser, Stefan H; Hylek, Elaine M; Kirchhof, Paulus; Lane, Deirdre A; Verheugt, Freek W A; Veltkamp, Roland; Lip, Gregory Y H
The choice of oral anticoagulant (OAC) for patients with atrial fibrillation (AF) may be influenced by individual clinical features or by patterns of risk factors and comorbidities. We reviewed analyses of subgroups of patients from trials of vitamin K antagonists vs. non-vitamin K oral anticoagulants (NOACs) for stroke prevention in AF with the aim to identify patient groups who might benefit from a particular OAC more than from another. In addition, we discuss the timing of initiation of anticoagulation. In the second of a two-part review, we discuss the use of NOAC for stroke prevention in the following subgroups of patients with AF: (vii) secondary stroke prevention in patients after stroke or transient ischaemic attack (TIA), (viii) patients with acute stroke requiring thrombolysis or thrombectomy, (ix) those initiating or restarting OAC treatment after stroke or TIA, (x) those with renal impairment on dialysis, (xi) the elderly, (xii) those at high risk of gastrointestinal bleeding, and (xiii) those with hypertension. In addition, we discuss adherence and compliance. Finally, we present a summary of treatment suggestions. In specific subgroups of patients with AF, evidence supports the use of particular NOACs and/or particular doses of anticoagulant. The appropriate choice of treatment for these subgroups will help to promote optimal clinical outcomes.
Malden, Nicholas J; Santini, Ario; Mather, Craig I; Gardner, Andrew
Fundamental to the surgical treatment of patients taking warfarin is the monitoring of the international normalised ratio (INR) before and after operation. A postoperative rise in INR was observed to be more common than a postoperative fall, so we decided to test the null hypothesis that there is no difference in the INR before and after minor dentoalveolar surgery. Data from the dental records of 71 patients treated consecutively over an 18-month period were examined, and INR before and after operation tested by a Friedman non-parametric test (ANOVA). Six cases were removed from the study because they required perioperative adjustment of their warfarin. There was a significant increase in the postoperative INR for the whole group. Further analysis showed that a significant increase in the postoperative INR for the multiple extraction and surgical removal group was the most likely cause for the rise in the whole group. There was no significant increase between men and women, those taking antibiotics preoperatively, and those not doing so, or in those having a single tooth extracted. We found an association between the degree of surgical intervention and the likelihood of anticoagulation being affected. Postoperative INR in this group should be monitored carefully.
Kurosawa, Yuko; Nirengi, Shinsuke; Homma, Toshiyuki; Esaki, Kazuki; Ohta, Mitsuhiro; Clark, Joseph F.; Hamaoka, Takafumi
Our aim was to determine the quantitative effects of a single-dose of Nattokinase (NK) administration on coagulation/fibrinolysis parameters comprehensively in healthy male subjects. A double-blind, placebo-controlled cross-over NK intervention study was carried out in 12 healthy young males. Following the baseline blood draw, each subject was randomized to receive either a single-dose of 2,000 FU NK (NSK-SD, Japan Bio Science Laboratory Co., Ltd) or placebo with subsequent cross-over of the groups. Subjects donated blood samples at 2, 4, 6 and 8 hours following administration for analysis of coagulation/fibrinolysis parameters. As a result, D-dimer concentrations at 6, and 8 hours, and blood fibrin/fibrinogen degradation products at 4 hours after NK administration elevated significantly (p < 0.05, respectively). Factor VIII activity declined at 4 and 6 hours (p < 0.05, respectively), blood antithrombin concentration was higher at 2 and 4 hours (p < 0.05, respectively), and the activated partial thromboplastin time prolonged significantly at 2 and 4 hours following NK administration (p < 0.05 and p < 0.01, respectively). All the changes, however, were within the normal range. In conclusion, thus, a single-dose of NK administration appears enhancing fibrinolysis and anti-coagulation via several different pathways simultaneously. PMID:26109079
Kurosawa, Yuko; Nirengi, Shinsuke; Homma, Toshiyuki; Esaki, Kazuki; Ohta, Mitsuhiro; Clark, Joseph F; Hamaoka, Takafumi
Our aim was to determine the quantitative effects of a single-dose of Nattokinase (NK) administration on coagulation/fibrinolysis parameters comprehensively in healthy male subjects. A double-blind, placebo-controlled cross-over NK intervention study was carried out in 12 healthy young males. Following the baseline blood draw, each subject was randomized to receive either a single-dose of 2,000 FU NK (NSK-SD, Japan Bio Science Laboratory Co., Ltd) or placebo with subsequent cross-over of the groups. Subjects donated blood samples at 2, 4, 6 and 8 hours following administration for analysis of coagulation/fibrinolysis parameters. As a result, D-dimer concentrations at 6, and 8 hours, and blood fibrin/fibrinogen degradation products at 4 hours after NK administration elevated significantly (p < 0.05, respectively). Factor VIII activity declined at 4 and 6 hours (p < 0.05, respectively), blood antithrombin concentration was higher at 2 and 4 hours (p < 0.05, respectively), and the activated partial thromboplastin time prolonged significantly at 2 and 4 hours following NK administration (p < 0.05 and p < 0.01, respectively). All the changes, however, were within the normal range. In conclusion, thus, a single-dose of NK administration appears enhancing fibrinolysis and anti-coagulation via several different pathways simultaneously.
Dorożyński, Przemysław P; Kulinowski, Piotr; Młynarczyk, Anna; Stanisz, Greg J
The magnetic resonance imaging (MRI) studies of controlled-release (CR) dosage forms can be roughly divided into two groups. The first comprises studies performed in static conditions (small solvent volumes and ambient temperature). Such studies have provided insight into molecular phenomena in hydrating polymeric matrices. The second group covers research performed in dynamic conditions (medium flow or stirring) related to drug dissolution. An important issue is supplementation of the MRI results with data obtained by complementary techniques, such as X-ray microtomography (μCT). As we discuss here, an understanding of the mechanism underlying the release of the drug from the dosage form will lead to the development of detailed, molecularly defined, CR dosage forms.
Franchini, Massimo; Liumbruno, Giancarlo M.; Bonfanti, Carlo; Lippi, Giuseppe
Arterial and venous thromboembolism are leading causes of morbidity and mortality around the world. For almost 70 years, heparins (unfractionated heparin and low molecular weight heparins) and vitamin K antagonists have been the leading therapeutic medical options for the treatment and prevention of thromboembolic disorders. Nevertheless, the many limitations of these traditional anticoagulants have fuelled the search for novel agents over the past 15 years, and a new class of oral anticoagulants that specifically target activated factor X and thrombin has been developed and is now commercially available. In this narrative review, the evolution of anticoagulant therapy is summarised, with a focus on newer oral anticoagulants. PMID:26710352
Lagi, Alfonso; Spini, Simona; Meucci, Elisa; Cartei, Alessandro; Cencetti, Simone
Background The aim of this study was to investigate the incidence of digestive hemorrhages in patients with non-valvular atrial fibrillation (NVAF), scheduled for oral anticoagulant therapy. Methods We conducted, over 24 months, a prospective, randomized, population-based observational study on consecutive patients with recurrent paroxysmal, persistent, or permanent NVAF, scheduled for oral anticoagulant therapy. The study initially included 268 patients with NVAF (162 males and 106 females) with a mean age of 74 years (range 42-86 years). Patients were split into two groups: those undergoing preventive Esophago-Gastro-Duodenoscopy (EGD) (Group A) and those who did not (Group B). All patients positive by EGD underwent medical treatment and subsequent 30-day endoscopic controls showed complete healing. The primary outcome of the study was to determine if previous EGD in patients with NVAF resulted in a low risk of bleeding during oral anticoagulant therapy. The two groups were comparable for most variables. Results Significant differences were found between groups for the incidence of antiarrhythmic drugs and for early hemorrhage (P <0.001). The incidences of early hemorrhages were significantly different between the two groups with 12 in group B (12%) and 2 in group A (1.7%). Conclusions Preventive EGD can identify hidden digestive diseases, which may increase the incidence of early hemorrhages.
Holbrook, Anne; Dormuth, Colin; Morrow, Richard; Lee, Agnes; Troyan, Sue; Li, Guowei; Pullenyegum, Eleanor
Introduction Anticoagulants are arguably the most important drug family of all, based on the frequency and duration of their use, and the clinical importance and frequency of benefits and harms. Several direct acting oral anticoagulants (DOACs) have recently joined warfarin for the treatment of atrial fibrillation, with a resultant significant expansion in use of oral anticoagulants (OACs). Our objectives are to compare safety and effectiveness of DOACs versus warfarin in a full population where anticoagulation management is good and to identify which types of patients do better with DOACs versus warfarin and vice versa. Methods and analysis This is a retrospective cohort study of all adults living in British Columbia who have a diagnosis of atrial fibrillation in hospital or medical service data, and a first prescription for an OAC. Coprimary outcomes are ischaemic stroke and systemic embolism (benefit) and major bleeding (harm). Secondary outcomes include net clinical benefit (composite of stroke, systemic embolism, major bleeds, myocardial infarction, pulmonary embolism and death), drug discontinuation and individual composite item occurrence. We will estimate the effects of treatment in a 2-year follow-up period, using time-to-event models with propensity score adjustment to control confounding. Secondary analyses will examine ‘as treated’ outcomes. Ethics and dissemination The protocol, data creation plan, privacy impact statement and data sharing agreements have been approved. Dissemination is planned via conferences and publications as well as directly to drug policy leaders. Information on the overall comparative effectiveness and safety of DOACs versus warfarin in a country with high quality anticoagulation management, as well as for vulnerable subgroups, will be an important addition to the literature. PMID:27884850
Unlike traditional anticoagulants, the more recently developed agents rivaroxaban, dabigatran and apixaban target specific factors in the coagulation cascade to attenuate thrombosis. Rivaroxaban and apixaban directly inhibit Factor Xa, whereas dabigatran directly inhibits thrombin. All three drugs exhibit predictable pharmacokinetic and pharmacodynamic characteristics that allow for fixed oral doses in a variety of settings. The population pharmacokinetics of rivaroxaban, and also dabigatran, have been evaluated in a series of models using patient data from phase II and III clinical studies. These models point towards a consistent pharmacokinetic and pharmacodynamic profile, even when extreme demographic factors are taken into account, meaning that doses rarely need to be adjusted. The exception is in certain patients with renal impairment, for whom pharmacokinetic modelling provided the rationale for reduced doses as part of some regimens. Although not routinely required, the ability to measure plasma concentrations of these agents could be advantageous in emergency situations, such as overdose. Specific pharmacokinetic and pharmacodynamic characteristics must be taken into account when selecting an appropriate assay for monitoring. The anti-Factor Xa chromogenic assays now available are likely to provide the most appropriate means of determining plasma concentrations of rivaroxaban and apixaban, and specific assays for dabigatran are in development. PMID:23809871
Lajoinie, A; Henin, E; Nguyen, K A; Malik, S; Mimouni, Y; Sapori, J M; Bréant, V; Cochat, P; Kassai, B
Selecting the most appropriate dosage form, that ensures safe administration and adherence of medications, is a major issue for children. Marketed drugs, however, have rarely been tested for their use in children. There is a need for more data on drug formulations administered to children to identify unmet needs, and drive future paediatric research. We observed, over a 12-month follow-up, 117,665 oral drug administrations to 1998 hospitalized children. Nine-tenths belonged to five Anatomical Therapeutic Chemical classes: Alimentary tract & metabolism, Nervous system, Cardiovascular system, Anti-infectives for systemic use and Blood & blood forming organs, one third of drug doses administered to school-age children and adolescents were liquids, and extemporaneous capsules were commonly used in younger children. Our study shows that despite the advantages of solid dosage forms and recent evidence from randomized controlled trials showing their acceptability in infants, they are seldom used in paediatric practice.
Başaran, Özcan; Dogan, Volkan; Beton, Osman; Tekinalp, Mehmet; Aykan, Ahmet Çağrı; Kalaycıoğlu, Ezgi; Bolat, Ismail; Taşar, Onur; Şafak, Özgen; Kalçık, Macit; Yaman, Mehmet; İnci, Sinan; Altıntaş, Bernas; Kalkan, Sedat; Kırma, Cevat; Biteker, Murat
The definition of non-valvular atrial fibrillation (NVAF) is controversial. We aimed to assess the impact of valvular heart disease on stroke prevention strategies in NVAF patients. The RAMSES study was a multicenter and cross-sectional study conducted on NVAF patients (ClinicalTrials.gov identifier NCT02344901). The study population was divided into patients with significant valvular disease (SVD) and non-significant valvular disease (NSVD), whether they had at least one moderate valvular disease or not. Patients with a mechanical prosthetic valve and mitral stenosis were excluded. Baseline characteristics and oral anticoagulant (OAC) therapies were compared. In 5987 patients with NVAF, there were 3929 (66%) NSVD and 2058 (34%) SVD patients. The predominant valvular disease was mitral regurgitation (58.1%), followed by aortic regurgitation (24.1%) and aortic stenosis (17.8%). Patients with SVD had higher CHA2DS2VASc [3.0 (2.0; 4.0) vs. 4.0 (2.0; 5.0), p < 0.001] and HAS-BLED [2.0 (1.0; 2.0) vs. 2.0 (1.0; 2.0), p = 0.004] scores compared to patients with NSVD. Overall, 2763 (71.2%) of NSVD and 1515 (73.8%) of SVD patients were on OAC therapy (p = 0.035). When the patients with SVD were analyzed separately, the mean CHA2DS2VASc and HAS-BLED scores were higher in patients with mitral regurgitation compared to patients with aortic regurgitation and aortic stenosis [4.0 (3.0; 5.0), 3.0 (2.0; 4.0), 3.0 (2.0; 4.0) p < 0.001 and 2.0 (1.0; 3.0), 1.0 (1.0; 2.0), 1.0 (0.0; 2.0) p < 0.001, respectively]. In patients with SVD, 65.7% of mitral regurgitation, 82.6% of aortic regurgitation and 88.0% of aortic stenosis patients were on OAC therapy. One out of three NVAF patients had at least one moderate valvular heart disease with the predominance of mitral regurgitation. Patients with SVD were at greater risk of stroke and bleeding compared to patients with NSVD. Although patients with mitral regurgitation should be given more aggressive anticoagulant therapy
Casajuana, Josep; Iglesias, Begoña; Fàbregas, Mireia; Fina, Francesc; Vallès, Joan-Antoni; Aragonès, Rosa; Benítez, Mència; Zabaleta, Edurne
Background Influenza vaccines are recommended for administration by the intramuscular route. However, many physicians use the subcutaneous route for patients receiving an oral anticoagulant because this route is thought to induce fewer hemorrhagic side effects. Our aim is to assess the safety of intramuscular administration of influenza vaccine in patients on oral anticoagulation therapy. Methods Design: Randomised, controlled, single blinded, multi-centre clinical trial. Setting: 4 primary care practices in Barcelona, Spain. Participants: 229 patients on oral anticoagulation therapy eligible for influenza vaccine during the 2003–2004 season. Interventions: intramuscular administration of influenza vaccine in the experimental group (129 patients) compared to subcutaneous administration in the control group (100 patients). Primary outcome: change in the circumference of the arm at the site of injection at 24 hours. Secondary outcomes: appearance of local reactions and pain at 24 hours and at 10 days; change in INR (International Normalized Ratio) at 24 hours and at 10 days. Analysis was by intention to treat using the 95% confidence intervals of the proportions or mean differences. Results Baseline variables in the two groups were similar. No major side effects or major haemorrhage during the follow-up period were reported. No significant differences were observed in the primary outcome between the two groups. The appearance of local adverse reactions was more frequent in the subcutaneous administration group (37,4% vs. 17,4%, 95% confidence interval of the difference 8,2% to 31,8%). Conclusion This study shows that the intramuscular administration route of influenza vaccine in patients on anticoagulant therapy does not have more side effects than the subcutaneous administration route. Registration number NCT00137579 at clinicaltrials.gov PMID:18507871
Shi, Quan; Xu, Juan; Zhang, Tong; Zhang, Bin; Liu, Hongchen
Background and Objective: Minor dental surgery is invasive and hemorrhagic. Thus, in patients treated with anticoagulants, the bleeding risk related to these invasive procedures is concerning. The aim of this meta-analysis is to evaluate this risk by comparing the post-operative bleeding rates of oral anticoagulation treatment (OAT) patients (without interrupted or altered anticoagulant intake) with non-OAT patients. Methods: PubMed, Embase and the Cochrane Library were searched for eligible studies that compared the post-operative (following minor dental surgery) bleeding rates of OAT patients without interrupted or altered therapy with those of non-OAT patients. Relative risk (RR) and 95% confidence interval (CI) were calculated. Subgroup analyses were used to identify the association between the bleeding rate and different dental surgeries or anticoagulants. Results: Thirty two full text articles were assessed for eligibility and 20 studies were excluded according to the selection criteria. Finally, 12 studies and a total of 2102 OAT patients and 2271 non-OAT patients were included. A pooled analysis indicated that the post-operative bleeding risk in OAT patients is higher than that of non-OAT patients (RR: 2.794, 95% CI: 1.722–4.532, P = 0.000). The pooled RRs in the dental implant surgery and dental extraction subgroups were 2.136 (95% CI: 0.825–5.531, P = 0.118) and 2.003 (95% CI: 0.987–4.063, P = 0.054), respectively. As for the different oral anticoagulants, the pooled RR in the subgroup of new oral anticoagulants (NOACs) was 1.603 (95% CI: 0.430–5.980, P = 0.482), while the pooled RR in the vitamin K antagonists subgroup was 3.067 (95% CI: 1.838–5.118, P = 0.000). Conclusion: Under current evidence, OAT patients were under a higher post-operative bleeding risk than the non-OAT patients following minor dental surgery. For the dental implant surgeries and dental extractions, our study failed to demonstrate a higher risk of bleeding in the OAT
Shi, Quan; Xu, Juan; Zhang, Tong; Zhang, Bin; Liu, Hongchen
Background and Objective: Minor dental surgery is invasive and hemorrhagic. Thus, in patients treated with anticoagulants, the bleeding risk related to these invasive procedures is concerning. The aim of this meta-analysis is to evaluate this risk by comparing the post-operative bleeding rates of oral anticoagulation treatment (OAT) patients (without interrupted or altered anticoagulant intake) with non-OAT patients. Methods: PubMed, Embase and the Cochrane Library were searched for eligible studies that compared the post-operative (following minor dental surgery) bleeding rates of OAT patients without interrupted or altered therapy with those of non-OAT patients. Relative risk (RR) and 95% confidence interval (CI) were calculated. Subgroup analyses were used to identify the association between the bleeding rate and different dental surgeries or anticoagulants. Results: Thirty two full text articles were assessed for eligibility and 20 studies were excluded according to the selection criteria. Finally, 12 studies and a total of 2102 OAT patients and 2271 non-OAT patients were included. A pooled analysis indicated that the post-operative bleeding risk in OAT patients is higher than that of non-OAT patients (RR: 2.794, 95% CI: 1.722-4.532, P = 0.000). The pooled RRs in the dental implant surgery and dental extraction subgroups were 2.136 (95% CI: 0.825-5.531, P = 0.118) and 2.003 (95% CI: 0.987-4.063, P = 0.054), respectively. As for the different oral anticoagulants, the pooled RR in the subgroup of new oral anticoagulants (NOACs) was 1.603 (95% CI: 0.430-5.980, P = 0.482), while the pooled RR in the vitamin K antagonists subgroup was 3.067 (95% CI: 1.838-5.118, P = 0.000). Conclusion: Under current evidence, OAT patients were under a higher post-operative bleeding risk than the non-OAT patients following minor dental surgery. For the dental implant surgeries and dental extractions, our study failed to demonstrate a higher risk of bleeding in the OAT patients
Diener, Hans-Christoph; Aisenberg, James; Ansell, Jack; Atar, Dan; Breithardt, Günter; Eikelboom, John; Ezekowitz, Michael D; Granger, Christopher B; Halperin, Jonathan L; Hohnloser, Stefan H; Hylek, Elaine M; Kirchhof, Paulus; Lane, Deirdre A; Verheugt, Freek W A; Veltkamp, Roland; Lip, Gregory Y H
Patients with atrial fibrillation (AF) have a high risk of stroke and mortality, which can be considerably reduced by oral anticoagulants (OAC). Recently, four non-vitamin-K oral anticoagulants (NOACs) were compared with warfarin in large randomized trials for the prevention of stroke and systemic embolism. Today's clinician is faced with the difficult task of selecting a suitable OAC for a patient with a particular clinical profile or a particular pattern of risk factors and concomitant diseases. We reviewed analyses of subgroups of patients from trials of vitamin K antagonists vs. NOACs for stroke prevention in AF with the aim to identify patient groups who might benefit from a particular OAC more than from another. In the first of a two-part review, we discuss the choice of NOAC for stroke prevention in the following subgroups of patients with AF: (i) stable coronary artery disease or peripheral artery disease, including percutaneous coronary intervention with stenting and triple therapy; (ii) cardioversion, ablation and anti-arrhythmic drug therapy; (iii) mechanical valves and rheumatic valve disease, (iv) patients with time in therapeutic range of >70% on warfarin; (v) patients with a single stroke risk factor (CHA2DS2VASc score of 1 in males, 2 in females); and (vi) patients with a single first episode of paroxysmal AF. Although there are no major differences in terms of efficacy and safety between the NOACs for some clinical scenarios, in others we are able to suggest that particular drugs and/or doses be prioritized for anticoagulation.
Wilcox, Ryan; Pendleton, Robert C; Smock, Kristi J; Rodgers, George M
Dabigatran etexilate is an oral direct thrombin inhibitor that has been approved by the US Food and Drug Administration for the prevention of stroke and systemic embolization in patients with nonvalvular atrial fibrillation. It has also been studied for the prevention of venous thromboembolism in patients after hip and knee arthroplasty and for treatment of venous thromboembolism. Although routine laboratory monitoring is not needed, there are clinical scenarios in which physicians will need to have a clear understanding of drug pharmacology, laboratory assessment, and reversibility of this drug to make appropriate clinical decisions. We review the pharmacology of dabigatran etexilate, pertinent clinical trials, and the effects of dabigatran etexilate on prothrombin time, activated partial thromboplastin time, thrombin time, and ecarin clotting time. We also provide an approach to patients on dabigatran etexilate who are bleeding, have a suspected therapeutic failure, or require periprocedural management.
Tomaszuk-Kazberuk, Anna; Lisowska, Anna; Sobkowicz, Bożena; Młodawska, Elżbieta; Łopatowska, Paulina; Kosacka, Urszula; Krajewska, Agnieszka; Musiał, Włodzimierz J
We present a case of 70-year old male after coronary by-pass surgery and mitral bioprosthesis implantation due to infective endocarditis, with continuous atrial fibrillation, who was admitted to the hospital due to the worsening of the heart failure. He was on oral antivitamine K agents with therapeutic value of INR. On echocardiography we found enlargement of all cavities with extremely big left atrium (9.5 cm) and poor contractile left ventricular function (EF 25%). An enormously big old thrombus was found in the left atrium. The patient was disqualified from surgical treatment. Treatment with unfractionated heparin was unsuccessful. We discuss if standard antithrombotic treatment is always sufficient in such unusual cases.
Zanon, Ezio; Martinelli, Franco; Bacci, Christian; Cordioli, GianPiero; Girolami, Antonio
We found no prospective studies on dental extraction in anticoagulated patients in the literature, even though most authors suggest that there is no need to change anticoagulant treatment and to utilize a local haemostatic measure after extraction. In the present study, we have verified the incidence of bleeding complications after dental extraction in a group of 250 consecutive anticoagulated patients. Two hundred and fifty non-anticoagulated subjects requiring dental extraction represented the control group. In all patients, anticoagulant treatment was not changed (International Normalized Ratio, 1.8-4) and local haemostatic measures (fibrin sponge, silk suture and a gauze saturated with tranexamic acid) were used. All procedures were performed in an outpatient clinic setting. We registered four bleeding complications in the group of anticoagulated patients and three in the control group. The difference of bleeding complications in the two groups was not statistically different (relative risk, 1.14; 95% confidence interval, 0.29-6.04; P = 0.7). None of the post-operative late bleeding required hospitalization and/or blood transfusions, and further local measures were sufficient to stop the bleeding. The protocol proposed in the present study makes dental extractions in anticoagulated patients possible on an outpatient basis with a cost reduction for the community and minor discomfort for the patients.
Calderone, Alicia; Stevens, Wendy; Prior, David; Nandurkar, Harshal; Gabbay, Eli; Proudman, Susanna M; Williams, Trevor; Celermajer, David; Sahhar, Joanne; Wong, Peter K K; Thakkar, Vivek; Dwyer, Nathan; Wrobel, Jeremy; Chin, Weng; Liew, Danny; Staples, Margaret; Buchbinder, Rachelle; Nikpour, Mandana
Introduction Systemic sclerosis (SSc) is a severe and costly multiorgan autoimmune connective tissue disease characterised by vasculopathy and fibrosis. One of the major causes of SSc-related death is pulmonary arterial hypertension (PAH), which develops in 12–15% of patients with SSc and accounts for 30–40% of deaths. In situ thrombosis in the small calibre peripheral pulmonary vessels resulting from endothelial dysfunction and an imbalance of anticoagulant and prothrombotic mediators has been implicated in the complex pathophysiology of SSc-related PAH (SSc-PAH), with international clinical guidelines recommending the use of anticoagulants for some types of PAH, such as idiopathic PAH. However, anticoagulation has not become part of standard clinical care for patients with SSc-PAH as only observational evidence exists to support its use. Therefore, we present the rationale and methodology of a phase III randomised controlled trial (RCT) to evaluate the efficacy, safety and cost-effectiveness of anticoagulation in SSc-PAH. Methods and analysis This Australian multicentre RCT will compare 2.5 mg apixaban with placebo, in parallel treatment groups randomised in a 1:1 ratio, both administered twice daily for 3 years as adjunct therapy to stable oral PAH therapy. The composite primary outcome measure will be the time to death or clinical worsening of PAH. Secondary outcomes will include functional capacity, health-related quality of life measures and adverse events. A cost-effectiveness analysis of anticoagulation versus placebo will also be undertaken. Ethics and dissemination Ethical approval for this RCT has been granted by the Human Research Ethics Committees of all participating centres. An independent data safety monitoring board will review safety and tolerability data for the duration of the trial. The findings of this RCT are to be published in open access journals. Trial registration number ACTRN12614000418673, Pre-results. PMID:27932335
Nielsen, Peter Brønnum; Skjøth, Flemming; Søgaard, Mette; Kjældgaard, Jette Nordstrøm; Lip, Gregory Y H; Larsen, Torben Bjerregaard
Objective To examine clinical effectiveness and safety of apixaban 2.5 mg, dabigatran 110 mg, and rivaroxaban 15 mg compared with warfarin among patients with atrial fibrillation who had not previously taken an oral anticoagulant.Design Propensity weighted (inverse probability of treatment weighted) nationwide cohort study.Setting Individual linked data from three nationwide registries in Denmark.Participants Patients with non-valvular atrial fibrillation filling a first prescription for an oral anticoagulant from August 2011 to February 2016. Patients who filled a prescription for a standard dose non-vitamin K antagonist oral anticoagulant (novel oral anticoagulants, NOACs) were excluded. To control for baseline differences in the population, a propensity score for receipt of either of the four treatment alternatives was calculated to apply an inverse probability treatment weight.Intervention Initiated anticoagulant treatment (dabigatran 110 mg, rivaroxaban 15 mg, apixaban 2.5 mg, and warfarin).Main outcome measures Patients were followed in the registries from onset of treatment for the primary effectiveness outcome of ischaemic stroke/systemic embolism and for the principal safety outcome of any bleeding events.Results Among 55 644 patients with atrial fibrillation who met inclusion criteria, the cohort was distributed according to treatment: apixaban n=4400; dabigatran n=8875; rivaroxaban n=3476; warfarin n=38 893. The overall mean age was 73.9 (SD 12.7), ranging from a mean of 71.0 (warfarin) to 83.9 (apixaban). During one year of follow-up, apixaban was associated with higher (weighted) event rate of ischaemic stroke/systemic embolism (4.8%), while dabigatran, rivaroxaban, and warfarin had event rates of 3.3%, 3.5%, and 3.7%, respectively. In the comparison between a non-vitamin K antagonist oral anticoagulant and warfarin in the inverse probability of treatment weighted analyses and investigation of the effectiveness outcome, the hazard ratios
Guimarães, Patrícia O; Kaatz, Scott; Lopes, Renato D
Atrial fibrillation (AF) is an important risk factor for thromboembolic events, and anticoagulation therapy can reduce this risk. Vitamin K antagonists (VKAs), such as warfarin, have been used for decades in patients with AF for stroke prevention. Currently, non-VKA oral anticoagulants (NOACs) are approved and available for non-valvular AF patients who are at increased risk of stroke. These agents are safe and effective and have important advantages over VKAs, such as significant reduction in intracranial hemorrhage and no need for routine laboratory monitoring. Thus, should all VKA-treated patients be switched to a NOAC? The aims of this article are: 1) to review the advantages of NOACs over VKAs; 2) to identify the group of patients who most benefit from receiving a NOAC and, therefore, are higher priority to be switched from VKAs; and 3) to provide clinical and practical guidance on how to switch patients safely from VKAs to NOACs. PMID:26379443
Arnao, Valentina; Agnelli, Giancarlo; Paciaroni, Maurizio
In patients with non-valvular atrial fibrillation (NVAF) and history of transient ischemic attack (TIA) or stroke, the rate of vascular events is higher in comparison to patients without history of stroke or TIA. A meta-analysis of direct oral anticoagulants (DOACs) studies, including only patients with history of stroke or TIA, report a significant reduction of 15 % in the rates of composite of stroke and systemic embolism in patients treated with DOACs, compared to those treated with warfarin. Furthermore, a reduction of 14 % for major bleeding, as well as a 56 % reduction for hemorrhagic stroke over a median follow-up of 1.8-2.0 years is reported. The combination of DOACs and antiplatelet agents carries the potential of additive benefits in patients with NVAF and other vascular diseases. However, the rate of major bleeding is higher among patients who receive concomitantly antiplatelet agents, compared to those taking only a single drug category. The risk of major bleeding seems to be higher among patients receiving dual antiplatelet agents, compared to those receiving a single antiplatelet drug. When NVAF is associated with an acute coronary syndrome requiring dual antiplatelet therapy (e.g. coronary angioplasty and stenting), DOACs plus this therapy should be considered. However, this therapy has to be administered for the shortest possible time, according to the patient's haemorrhagic and thrombotic risks, and stent type. When NVAF is associated with carotid stenosis, a single antiplatelet therapy should be considered. Regarding carotid revascularization, it seems preferable to treat these patients with endarterectomy, so to avoid dual antiplatelet therapy, which is generally administered after stenting.
Stein, Marco; Misselwitz, Björn; Hamann, Gerhard F; Kolodziej, Malgorzata; Reinges, Marcus H T; Uhl, Eberhard
Pre-treatment with antiplatelet agents is described to be a risk factor for mortality after spontaneous intracerebral hemorrhage (ICH). However, the impact of antithrombotic agents on mortality in patients who undergo hematoma evacuation compared to conservatively treated patients with ICH remains controversial. This analysis is based on a prospective registry for quality assurance in stroke care in the State of Hesse, Germany. Patients' data were collected between January 2008 and December 2012. Only patients with the diagnosis of spontaneous ICH were included (International Classification of Diseases 10th Revision codes I61.0-I61.9). Predictors of in-hospital mortality were determined by univariate analysis. Predictors with P<0.1 were included in a binary logistic regression model. The binary logistic regression model was adjusted for age, initial Glasgow Coma Score (GCS), the presence of intraventricular hemorrhage (IVH), and pre-ICH disability prior to ictus. In 8,421 patients with spontaneous ICH, pre-treatment with oral anticoagulants or antiplatelet agents was documented in 16.3% and 25.1%, respectively. Overall in-hospital mortality was 23.2%. In-hospital mortality was decreased in operatively treated patients compared to conservatively treated patients (11.6% versus 24.0%; P<0.001). Patients with antiplatelet pre-treatment had a significantly higher risk of death during the hospital stay after hematoma evacuation (odds ratio [OR]: 2.5; 95% confidence interval [CI]: 1.24-4.97; P=0.010) compared to patients without antiplatelet pre-treatment treatment (OR: 0.9; 95% CI: 0.79-1.09; P=0.376). In conclusion a higher rate of in-hospital mortality after pre-treatment with antiplatelet agents in combination with hematoma evacuation after spontaneous ICH was observed in the presented cohort.
Beyer-Westendorf, Jan; Förster, Kati; Ebertz, Franziska; Gelbricht, Vera; Schreier, Thomas; Göbelt, Maria; Michalski, Franziska; Endig, Heike; Sahin, Kurtulus; Tittl, Luise; Weiss, Norbert
Aims Worldwide, rivaroxaban is increasingly used for stroke prevention in atrial fibrillation (SPAF) but little is known about the rates of or reasons for rivaroxaban discontinuations in daily care. Using data from a prospective, non-interventional oral anticoagulation (NOAC) registry, we analysed rivaroxaban treatment persistence. Methods and results Persistence with rivaroxaban in SPAF was assessed in an ongoing, prospective, non-interventional registry of >2600 NOAC patients from daily care using the Kaplan–Meier time-to-first-event analysis. Reasons for and management of rivaroxaban discontinuation were assessed. Potential baseline risk factors for treatment discontinuation were evaluated using Cox regression analysis. Between October 2011 and April 2014, 1204 rivaroxaban SPAF patients were enrolled [39.3% switched from vitamin K antagonists (VKAs) and 60.7% newly treated patients]. Of these, 223 patients (18.5%) stopped rivaroxaban during follow-up (median 544 days), which translates into a discontinuation rate of 13.6 (95% CI 11.8–15.4) per 100 patient-years. Most common reasons for treatment discontinuations were bleeding complications (30% of all discontinuations), followed by other side-effects (24.2%) and diagnosis of stable sinus rhythm (9.9%). A history of chronic heart failure (HR 1.43; 95% CI 1.09–1.87; P = 0.009) or diabetes (HR 1.39; 95% CI 1.06–1.82; P = 0.018) were the only statistically significant baseline risk factors for rivaroxaban discontinuation. After discontinuation of rivaroxaban, patients received antiplatelet therapy (31.8%), VKA (24.2%), another NOAC (18.4%), heparin (9.9%), or nothing (15.7%). Conclusion Our data indicate that overall persistence with rivaroxaban therapy is high, with a discontinuation rate of ∼15% in the first year of treatment and few additional discontinuations thereafter. PMID:25694537
Bang, Oh Young; Hong, Keun-Sik; Heo, Ji Hoe
After recent randomized control trials (RCTs), non-vitamin K oral anticoagulants (NAOAs) are now widely being used in patients with atrial fibrillation (AF) worldwide. However, current guidelines for the use of NOACs in patients with AF are derived mostly using a Caucasian population and non-stroke patients. Relatively few Asian patients with AF and stroke are included in the recent RCTs. As a result, the optimal use of NOACs in this particular group of patients is remains to be settled. The optimal dose of NOACs and response to current dose of NOACs of Asian patients with AF and stroke may differ from those of westerners and patients without stroke. We reviewed available research on NOACs by searching PubMed and ClinicalTrials.gov published in English up to December 2015. In this review, the characteristics of Asian AF patients with prior stroke/transient ischemic attack, which might influence the efficacy and safety profiles of NOACs, are discussed. In addition, we summarize the risk factors for bleeding complications on NOACs, which are related or unrelated with the blood level of NOACs. Lastly, we provide recent data of reduced dose of NOACs from RCTs or large cohorts. The results reviewed herein call for clinical trials to test whether a reduced dose of NOACs is beneficial in Asian patients with AF and stroke. In the meantime, further researches are needed to establish the safety and efficacy of dose-adjusted NOACs considering both blood levels of NOACs and fragility of patients in Asian patients with AF and stroke. PMID:27170995
Executive Summary Subject of the Evidence-Based Analysis The purpose of this evidence based analysis report is to examine the safety and effectiveness of point-of-care (POC) international normalized ratio (INR) monitoring devices for patients on long-term oral anticoagulation therapy (OAT). Clinical Need: Target Population and Condition Long-term OAT is typically required by patients with mechanical heart valves, chronic atrial fibrillation, venous thromboembolism, myocardial infarction, stroke, and/or peripheral arterial occlusion. It is estimated that approximately 1% of the population receives anticoagulation treatment and, by applying this value to Ontario, there are an estimated 132,000 patients on OAT in the province, a figure that is expected to increase with the aging population. Patients on OAT are regularly monitored and their medications adjusted to ensure that their INR scores remain in the therapeutic range. This can be challenging due to the narrow therapeutic window of warfarin and variation in individual responses. Optimal INR scores depend on the underlying indication for treatment and patient level characteristics, but for most patients the therapeutic range is an INR score of between 2.0 and 3.0. The current standard of care in Ontario for patients on long-term OAT is laboratory-based INR determination with management carried out by primary care physicians or anticoagulation clinics (ACCs). Patients also regularly visit a hospital or community-based facility to provide a venous blood samples (venipuncture) that are then sent to a laboratory for INR analysis. Experts, however, have commented that there may be under-utilization of OAT due to patient factors, physician factors, or regional practice variations and that sub-optimal patient management may also occur. There is currently no population-based Ontario data to permit the assessment of patient care, but recent systematic reviews have estimated that less that 50% of patients receive OAT on a
Balducci, Anna Giulia; Magosso, Enrico; Colombo, Gaia; Sonvico, Fabio; Khan, Nurzalina Abdul Karim; Yuen, Kah Hay; Bettini, Ruggero; Colombo, Paolo; Rossi, Alessandra
Artemisinin, a poorly water-soluble antimalarial drug, presents a low and erratic bioavailability upon oral administration. The aim of this work was to study an agglomerated powder dosage form for oral administration of artemisinin based on the artemisinin/β-cyclodextrin primary microparticles. These primary microparticles were prepared by spray-drying a water-methanol solution of artemisinin/β-cyclodextrin. β-Cyclodextrin in spray-dried microparticles increased artemisinin water apparent solubility approximately sixfold. The thermal analysis evidenced a reduction in the enthalpy value associated with drug melting, due to the decrease in drug crystallinity. The latter was also evidenced by powder X-ray diffraction analysis, while (13)C-NMR analysis indicated the partial complexation with β-cyclodextrin. Agglomerates obtained by sieve vibration of spray-dried artemisinin/β-cyclodextrin primary microparticles exhibited free flowing and close packing properties compared with the non-flowing microparticulate powder. The in vitro dissolution rate determination of artemisinin from the agglomerates showed that in 10 min about 70% of drug was released from the agglomerates, whereas less than 10% of artemisinin was dissolved from raw material powder. Oral administration of agglomerates in rats yielded higher artemisinin plasma levels compared to those of pure drug. In the case of the agglomerated powder, a 3.2-fold increase in drug fraction absorbed was obtained.
Wheeler, D S; Giugliano, R P; Rangaswami, J
Anticoagulation-related nephropathy (ARN) is a significant but underdiagnosed complication of anticoagulation that is associated with increased renal morbidity and all-cause mortality. Originally described in patients receiving supratherapeutic doses of warfarin who had a distinct pattern of glomerular hemorrhage on kidney biopsy, ARN is currently defined as acute kidney injury (AKI) without obvious etiology in the setting of an International Normalized Ratio (INR) of > 3.0. The underlying molecular mechanism is thought to be warfarin-induced thrombin depletion; however, newer studies have hinted at an alternative mechanism involving reductions in activated protein C and endothelial protein C receptor signaling. Prompt recognition of ARN is critical, as it is associated with accelerated progression of chronic kidney disease, and significant increases in short-term and long-term all-cause mortality. Prior investigations into ARN have almost universally focused on anticoagulation with warfarin; however, recent case reports and animal studies suggest that it can also occur in patients taking novel oral anticoagulants. Differences in the incidence and severity of ARN between patients taking warfarin and those taking novel oral anticoagulants are unknown; a post hoc analysis of routinely reported adverse renal outcomes in clinical trials comparing warfarin and novel oral anticoagulants found no significant difference in the rates of AKI, a prerequisite for ARN. Given the significant impact of ARN on renal function and all-cause mortality, a thorough understanding of the pathophysiology, molecular mechanisms, clinical spectrum and therapeutic interventions for ARN is crucial to balance the risks and benefits of anticoagulation and optimize treatment.
Caillard, Romain; Lapointe, Nicolas
Although the intestinal microbial community is still incompletely understood, there is strong evidence of the benefits of using probiotics to address some medical states or conditions. As a result, the probiotics oral supplements market has exploded during the last few years. However, while their sensitivity to gastric juices, acidic pH and bile is well known, most of these oral forms would not guarantee any survival of the strains in such conditions. In this work, we have studied the resistance to simulated gastric juices of several commercially available probiotics products. These included sixteen strains and ten oral forms such as enteric/non-enteric capsules/tablets and microencapsulated strains. Results demonstrated that all tested strains showed high sensitivity to acidic conditions and suggested that most of these microorganisms would not show any viability when immersed in the stomach at fasting. Most probiotics oral forms did not provide any protection to strains, unless these forms presented strong enteric protection. Consequently, the efficacy of non-enteric products to fully provide to the patient the benefits related to the consumption of probiotics supplement would be strongly questionable. This study underlines the chasm between the current opinion about probiotics protection needs and the products proposed by many companies in the dietary supplements area.
... suspension containing orbifloxacin for the treatment of various bacterial infections in dogs and cats. DATES...) Oral Suspension for the treatment of various bacterial infections in dogs and cats. The NADA is...), and Streptococcus equisimilis. (2) Cats--(i) Amount. 3.4 mg/lb (7.5 mg/kg) of body weight once...
...) Conditions of use in dogs and cats--(1) Amount. Administer orally as a single, daily dose or divided into two... (/lb)) of body weight. (ii) Cats. 5 mg/kg (2.27 mg/lb) of body weight. (2) Indications for use. For...
Orso, Francesco; Barucci, Riccardo; Fracchia, Stefania; Mannarino, Giulio; Pratesi, Alessandra; Fattirolli, Francesco
Atrial Fibrillation (AF) is the most frequent cardiac arrhythmia and its incidence increases with age reaching a 10% prevalence in the oldest old. Patients with AF have a five-fold increase in the risk of stroke. Current guidelines on AF management recommend the prescription of oral anticoagulant therapy in patients at medium and high risk of thromboembolic events. Advanced age is a risk factor for stroke in AF, but despite clear evidences a high rate of OAT under prescription is reported and particularly in the oldest old. Among the main causes of this phenomenon an enhanced risk of bleeding is often reported: this due to several factors: risk of falls, the presence of comorbidity and polifarmacy and a reduction in compliance and adherence that are common in the elderly. In recent years the international scenario in the management of OAT has significantly changed since the introduction of the new oral anticoagulants (NOA): Dabigatran, a direct thrombin inhibitor, and two oral factor Xa inhibitors Rivaroxaban and Apixaban, which have all been tested in randomized clinical trial (RELY, ROCKET-AF e ARISTOTLE) which have demonstrated non inferiority compared to warfarin in the prevention of thromboembolic events with an optimal safety profile. NOA could be an important therapeutic opportunity for stroke prevention in elderly patients with AF even if the substantial differences in mean age, anthropometric measures and comorbidity of the patients enrolled in these trials compared with those of the real world setting, oblige some caution and discussion.
Moos, Rebecca K; Angerer, Jürgen; Dierkes, Georg; Brüning, Thomas; Koch, Holger M
Parabens are used as preservatives in personal care and consumer products, food and pharmaceuticals. Their use is controversial because of possible endocrine disrupting properties. In this study, we investigated metabolism and urinary excretion of methyl paraben (MeP), iso-butyl paraben (iso-BuP) and n-butyl paraben (n-BuP) after oral dosage of deuterium-labeled analogs (10 mg). Each volunteer received one dosage per investigated paraben separately and at least 2 weeks apart. Consecutive urine samples were collected over 48 h. In addition to the parent parabens (free and conjugated) which are already used as biomarkers of internal exposure and the known but non-specific metabolites, p-hydroxybenzoic acid (PHBA) and p-hydroxyhippuric acid (PHHA), we identified new, oxidized metabolites with hydroxy groups on the alkyl side chain (3OH-n-BuP and 2OH-iso-BuP) and species with oxidative modifications on the aromatic ring. MeP represented 17.4 % of the dose excreted in urine, while iso-BuP represented only 6.8 % and n-BuP 5.6 %. Additionally, for iso-BuP, about 16 % was excreted as 2OH-iso-BuP and for n-BuP about 6 % as 3OH-n-BuP. Less than 1 % was excreted as ring-hydroxylated metabolites. In all cases, PHHA was identified as the major but non-specific metabolite (57.2-63.8 %). PHBA represented 3.0-7.2 %. For all parabens, the majority of the oral dose captured by the above metabolites was excreted in the first 24 h (80.5-85.3 %). Complementary to the parent parabens excreted in urine, alkyl-chain-oxidized metabolites of the butyl parabens are introduced as valuable and contamination-free biomarkers of exposure.
Russo, Vincenzo; Rago, Anna; Proietti, Riccardo; Di Meo, Federica; Antonio Papa, Andrea; Calabrò, Paolo; D’Onofrio, Antonio; Nigro, Gerardo; AlTurki, Ahmed
The aim of our article is to provide a concise review for clinicians entailing the main studies that evaluated the efficacy and safety of target-specific oral anticoagulants (TSOAs) for thromboembolic stroke prevention in the real-world setting. Atrial fibrillation (AF) is one of the most common supraventricular arrhythmias that requires anticoagulation therapy to prevent stroke and systemic embolism. TSOAs, dabigatran, apixaban and rivaroxaban have become available as an alternative to warfarin anticoagulation in nonvalvular atrial fibrillation (NVAF). Randomized clinical trials showed non-inferior or superior results in efficacy and safety of the TSOAs compared with warfarin for stroke prevention in NVAF patients. For this reason, the 2012 update to the European Society of Cardiology guidelines for the management of AF recommends TSOAs as broadly preferable to vitamin K antagonists (VKAs) in the vast majority of patients with NVAF [Camm et al. 2012]. Although the clinical trial results and the guideline’s indications, there is a need for safety and efficacy data from unselected patients in everyday clinical practice. Recently, a large number of studies testing the efficacy and the safety of TSOAs in clinical practice have been published. The aim of our article is to provide a concise review for clinicians, outlining the main studies that evaluated the efficacy and safety of TSOAs for thromboembolic stroke prevention in the real-world setting. PMID:28255434
Kumar, Shashi; Danik, Stephan B; Altman, Robert K; Barrett, Conor D; Lip, Gregory Y H; Chatterjee, Saurav; Roubin, Gary S; Natale, Andrea; Danik, Jacqueline S
Non-vitamin K antagonist oral anticoagulants (NOACs) are frequently used to prevent stroke in patients with atrial fibrillation. These patients are often also on aspirin or other antiplatelet agents. It is possible that treatment with both NOACs and aspirin or other antiplatelet drug may be effective in decreasing stroke, but data are sparse regarding the efficacy and safety of using both agents for stroke prevention. To address these issues, data were pooled from the 4 recent randomized, controlled trials of NOACs: apixaban, rivaroxaban, dabigatran, and edoxaban, which included 42,411 patients; 14,148 (33.4%) were also on aspirin or other antiplatelet drug. The number of thromboembolic events among participants on NOAC and aspirin/antiplatelet was compared with the number of events in patients on NOAC alone. Bleeding rates were also compared between those on NOAC + aspirin/antiplatelet and on NOAC alone. These results were compared with thromboembolic and bleeding events in the warfarin + aspirin/antiplatelet versus warfarin alone. No greater risk for thromboembolism was seen in patients on NOACs compared with patients on both NOACs and aspirin/antiplatelet drug. In this nonrandomized comparison, there was initially a signal toward higher thromboembolic rates among NOAC users also on aspirin/antiplatelet drugs (relative risk, 1.16; 95% confidence intervals, 1.05, 1.29) when compared with NOAC alone. This likely reflected the higher CHADS2 scores of those on aspirin/antiplatelet drugs. When the analysis was limited to studies that included aspirin rather than other antiplatelet drugs, no difference was seen for thromboembolic rates comparing dual therapy to NOAC alone (relative risk, 1.02; 95% confidence intervals, 0.90, 1.15). Higher rates of bleeding were seen with aspirin/antiplatelet drug in conjunction with NOAC. In this meta-analysis and nonrandomized comparison of aspirin/antiplatelet users and nonusers also on anticoagulation, there was no additional
Kwon, Chang Hee; Kim, Minsu; Kim, Jun; Nam, Gi-Byoung; Choi, Kee-Joon; Kim, You-Ho
Background The efficacy and safety of non-vitamin K antagonist oral anticoagulants (NOACs) and warfarin in Asian octogenarian atrial fibrillation (AF) patients have not been established in a real-world setting. We aimed to evaluate the efficacy and safety of NOACs and warfarin in Korean octogenarian patients. Methods A total of 293 consecutive patients aged ≥ 80 years with non-valvular AF who had taken either NOACs (148 cases, 50.5%) or warfarin (145 cases, 49.5%) were retrospectively reviewed. The efficacy outcome was the composite of stroke or systemic embolism. The safety outcome was major bleeding. Results The follow-up duration was 375 patient-years (172 patient-years with NOACs and 203 patient-years with warfarin). Patients on NOACs were slightly older (P = 0.006) and had slightly higher HAS-BLED scores (P = 0.034). The efficacy of both anticoagulants was high (1.16% for NOACs vs. 2.98% for warfarin per 100 patient-years, P = 0.46). The safety outcome was relatively high in both NOACs and warfarin groups (8.96% vs. 12.46%, P = 0.29). The efficacy and safety outcomes tended to decrease non-significantly in low dose NOACs than in common dose NOACs or warfarin (0.85% vs. 1.84% vs. 2.98% in efficacy outcome, P = 0.69; and 6.97% vs. 13.29% vs. 12.46% in safety outcome, P = 0.34). Conclusions NOACs were highly effective for prevention of stroke or systemic embolism in Asian octogenarian AF patients. However, major bleeding occurred excessively high in both anticoagulant groups. Further study is required on the optimal anticoagulant regimen in octogenarian population. PMID:27605936
Agrawal, Shrutidevi; Panchagnula, Ramesh
Rifampicin is one of the oldest and most effective chemotherapeutic agents available for the treatment of tuberculosis but exhibits variable bioavailability from separate and fixed dose combination formulations, which has been identified as a major bottleneck in the effective treatment of tuberculosis. In this investigation, physico-chemical characterization, single dose pharmacokinetic studies and the permeability of rifampicin under physiological conditions in the rat were studied to trace the possible reasons for its variable absorption. Rifampicin exhibits very high solubility in acidic and basic pH, corresponding to the pH of the stomach and distal intestine, respectively, whereas it is moderately soluble at the jejunal pH. From single-dose pharmacokinetic studies and permeability characterization, rifampicin is a highly permeable molecule and thus according to BCS, it is a borderline class II drug. This investigation has ruled out the possibility of intrinsic solubility, effective permeability, drug decomposition, presystemic metabolism and interaction with other antituberculosis drugs as direct factors responsible for the variable bioavailability of rifampicin. However, it was found that the rate of dissolution in association with pH and the concentration-dependent absorption of rifampicin affects the in vivo performance of the dosage forms. In addition, this is the first report of methodology for correcting inlet concentration for permeability calculations of a chemically unstable molecule.
Kostewicz, Edmund S; Abrahamsson, Bertil; Brewster, Marcus; Brouwers, Joachim; Butler, James; Carlert, Sara; Dickinson, Paul A; Dressman, Jennifer; Holm, René; Klein, Sandra; Mann, James; McAllister, Mark; Minekus, Mans; Muenster, Uwe; Müllertz, Anette; Verwei, Miriam; Vertzoni, Maria; Weitschies, Werner; Augustijns, Patrick
Accurate prediction of the in vivo biopharmaceutical performance of oral drug formulations is critical to efficient drug development. Traditionally, in vitro evaluation of oral drug formulations has focused on disintegration and dissolution testing for quality control (QC) purposes. The connection with in vivo biopharmaceutical performance has often been ignored. More recently, the switch to assessing drug products in a more biorelevant and mechanistic manner has advanced the understanding of drug formulation behavior. Notwithstanding this evolution, predicting the in vivo biopharmaceutical performance of formulations that rely on complex intraluminal processes (e.g. solubilization, supersaturation, precipitation…) remains extremely challenging. Concomitantly, the increasing demand for complex formulations to overcome low drug solubility or to control drug release rates urges the development of new in vitro tools. Development and optimizing innovative, predictive Oral Biopharmaceutical Tools is the main target of the OrBiTo project within the Innovative Medicines Initiative (IMI) framework. A combination of physico-chemical measurements, in vitro tests, in vivo methods, and physiology-based pharmacokinetic modeling is expected to create a unique knowledge platform, enabling the bottlenecks in drug development to be removed and the whole process of drug development to become more efficient. As part of the basis for the OrBiTo project, this review summarizes the current status of predictive in vitro assessment tools for formulation behavior. Both pharmacopoeia-listed apparatus and more advanced tools are discussed. Special attention is paid to major issues limiting the predictive power of traditional tools, including the simulation of dynamic changes in gastrointestinal conditions, the adequate reproduction of gastrointestinal motility, the simulation of supersaturation and precipitation, and the implementation of the solubility-permeability interplay. It is
Skjøth, Flemming; Nielsen, Peter Brønnum; Kjældgaard, Jette Nordstrøm; Lip, Gregory Y H
Objective To study the effectiveness and safety of the non-vitamin K antagonist oral anticoagulants (novel oral anticoagulants, NOACs) dabigatran, rivaroxaban, and apixaban compared with warfarin in anticoagulant naïve patients with atrial fibrillation. Design Observational nationwide cohort study. Setting Three Danish nationwide databases, August 2011 to October 2015. Participants 61 678 patients with non-valvular atrial fibrillation who were naïve to oral anticoagulants and had no previous indication for valvular atrial fibrillation or venous thromboembolism. The study population was distributed according to treatment type: warfarin (n=35 436, 57%), dabigatran 150 mg (n=12 701, 21%), rivaroxaban 20 mg (n=7192, 12%), and apixaban 5 mg (n=6349, 10%). Main outcome measures Effectiveness outcomes defined a priori were ischaemic stroke; a composite of ischaemic stroke or systemic embolism; death; and a composite of ischaemic stroke, systemic embolism, or death. Safety outcomes were any bleeding, intracranial bleeding, and major bleeding. Results When the analysis was restricted to ischaemic stroke, NOACs were not significantly different from warfarin. During one year follow-up, rivaroxaban was associated with lower annual rates of ischaemic stroke or systemic embolism (3.0% v 3.3%, respectively) compared with warfarin: hazard ratio 0.83 (95% confidence interval 0.69 to 0.99). The hazard ratios for dabigatran and apixaban (2.8% and 4.9% annually, respectively) were non-significant compared with warfarin. The annual risk of death was significantly lower with apixaban (5.2%) and dabigatran (2.7%) (0.65, 0.56 to 0.75 and 0.63, 0.48 to 0.82, respectively) compared with warfarin (8.5%), but not with rivaroxaban (7.7%). For the combined endpoint of any bleeding, annual rates for apixaban (3.3%) and dabigatran (2.4%) were significantly lower than for warfarin (5.0%) (0.62, 0.51 to 0.74). Warfarin and rivaroxaban had comparable annual bleeding rates (5
Vivancos, Melanie; Barker, Jessica; Engbers, Sarah; Fischer, Carrie; Frederick, Jami; Friedt, Heather; Rybicka, Joanna M.; Stastny, Tereza; Banse, Heidi; Cribb, Alastair E.
Meloxicam, a non-steroidal anti-inflammatory drug, is approved for use in horses in several countries, but an equine formulation is not available in North America. However, meloxicam is being used in an extra-label manner in horses in Canada. The purpose of this study, therefore, was to assess the bioequivalence of an approved oral meloxicam suspension (Metacam 15 mg/mL for horses; Boehringer Ingelheim Vetmedica GmBH, Ingelheim, Germany) from the European Union with human meloxicam tablets (Meloxicam 15 mg tablets; TEVA Canada, Toronto, Ontario) compounded with molasses to improve palatability and administration. The geometric mean ratios (GMR test/reference) and the 90% confidence intervals of the pivotal pharmacokinetic parameters (area under the curve and maximum concentration) were within the defined limits of 80% to 125% generally accepted for products to be considered bioequivalent. Therefore, use of human meloxicam tablets compounded with molasses would be expected to produce a similar clinical response in horses as the approved oral product from the European Union. PMID:26130835
Agarwal, Vikas; Alayoubi, Alaadin; Siddiqui, Akhtar; Nazzal, Sami
The objectives of this study were to prepare a powdered self-emulsified (SEDDS) formulation of meloxicam and to compare its oral bioavailability against commercial Mobic tablets. The SEDDS formulation was prepared by in situ salt formation of meloxicam in a blend of lipid excipients and aqueous tris (hydroxymethyl) aminomethane solution. The liquid SEDDS was subsequently adsorbed on silica powder and was tested for size, flow, and crystal growth. The flowability index of the powdered SEDDS was borderline acceptable. Absence of crystal growth with storage was confirmed by DSC and PXRD studies. Dissolution of meloxicam from the powdered SEDDS was >90% vs. <12% for powdered meloxicam and <80% for the commercial tablets. Stability of the powdered formulations after storage in gelatin and HPMC capsules was also evaluated to study the effect of water migration from the fill into capsule shells. Capsules softened to a different extent as a function of fill material with HPMC capsules showing greater resistance to water migration. Finally, oral bioavailability of the formulations was evaluated in beagle dogs. Powdered meloxicam SEDDS formulation showed a 1.3-fold increase in AUC vs. commercial Mobic® tablets. Overall, this study described a novel SEDDS formulation of meloxicam and outlined a systematic approach to adsorbing and testing the flow and stability behavior of powdered SEDDS formulations.
Vivancos, Melanie; Barker, Jessica; Engbers, Sarah; Fischer, Carrie; Frederick, Jami; Friedt, Heather; Rybicka, Joanna M; Stastny, Tereza; Banse, Heidi; Cribb, Alastair E
Meloxicam, a non-steroidal anti-inflammatory drug, is approved for use in horses in several countries, but an equine formulation is not available in North America. However, meloxicam is being used in an extra-label manner in horses in Canada. The purpose of this study, therefore, was to assess the bioequivalence of an approved oral meloxicam suspension (Metacam 15 mg/mL for horses; Boehringer Ingelheim Vetmedica GmBH, Ingelheim, Germany) from the European Union with human meloxicam tablets (Meloxicam 15 mg tablets; TEVA Canada, Toronto, Ontario) compounded with molasses to improve palatability and administration. The geometric mean ratios (GMR test/reference) and the 90% confidence intervals of the pivotal pharmacokinetic parameters (area under the curve and maximum concentration) were within the defined limits of 80% to 125% generally accepted for products to be considered bioequivalent. Therefore, use of human meloxicam tablets compounded with molasses would be expected to produce a similar clinical response in horses as the approved oral product from the European Union.
Nair, Anita; Abrahamsson, Bertil; Barends, Dirk M; Groot, D W; Kopp, Sabine; Polli, James E; Shah, Vinod P; Dressman, Jennifer B
The present monograph reviews data relevant to applying the biowaiver procedure for the approval of immediate release (IR) multisource solid dosage forms containing amodiaquine hydrochloride (ADQ) as the single active pharmaceutical ingredient (API). Both biopharmaceutical and clinical data of ADQ were assessed. Solubility studies revealed that ADQ meets the "highly soluble" criteria according to World Health Organization (WHO) and European Medicines Agency (EMA) but fails to comply with the United States Food and Drug Administration (US FDA) specifications. Although metabolism hints at high permeability, available permeability data are too scanty to classify ADQ inequivocably as a Class I drug substance. According to WHO and EMA guidances, ADQ would be conservatively categorized as a Class III drug, whereas according to the US FDA specifications, it would fall into Class IV. ADQ has a wide therapeutic index. Furthermore, no cases of bioinequivalent products have been reported in the open literature. As risks associated with biowaiving appear minimal and requirements for "highly soluble" API are met in the WHO and EMA jurisdictions, the biowaiver procedure can be recommended for bioequivalence (BE) testing of multisource IR products containing ADQ as the only API, provided the test product contains excipients used in ADQ products approved in International Conference of Harmonisation and associated countries, and in similar amounts. Furthermore, both comparator and test should conform to "very rapidly dissolving" product criteria (≥85% dissolution of the API in 15 min at pH 1.2, 4.5, and 6.8) and the labeling should specify that the product not be coadministered with high-fat meals. If the comparator and/or test product fails to meet these criteria, BE needs to be established by pharmacokinetic studies in humans.
Kalantzi, L; Reppas, C; Dressman, J B; Amidon, G L; Junginger, H E; Midha, K K; Shah, V P; Stavchansky, S A; Barends, Dirk M
Literature data are reviewed on the properties of acetaminophen (paracetamol) related to the biopharmaceutics classification system (BCS). According to the current BCS criteria, acetaminophen is BCS Class III compound. Differences in composition seldom, if ever, have an effect on the extent of absorption. However, some studies show differences in rate of absorption between brands and formulations. In particular, sodium bicarbonate, present in some drug products, was reported to give an increase in the rate of absorption, probably caused by an effect on gastric emptying. In view of Marketing Authorizations (MAs) given in a number of countries to acetaminophen drug products with rapid onset of action, it is concluded that differences in rate of absorption were considered therapeutically not relevant by the Health Authorities. Moreover, in view of its therapeutic use, its wide therapeutic index and its uncomplicated pharmacokinetic properties, in vitro dissolution data collected according to the relevant Guidances can be safely used for declaring bioequivalence (BE) of two acetaminophen formulations. Therefore, accepting a biowaiver for immediate release (IR) acetaminophen solid oral drug products is considered scientifically justified, if the test product contains only those excipients reported in this paper in their usual amounts and the test product is rapidly dissolving, as well as the test product fulfils the criterion of similarity of dissolution profiles to the reference product.
Strauch, Stefanie; Dressman, Jennifer B; Shah, Vinod P; Kopp, Sabine; Polli, James E; Barends, Dirk M
The biowaiver approach permits evaluation of bioequivalence (BE) using a set of laboratory tests, obviating the need for expensive and time-consuming pharmacokinetic BE studies provided that both the active pharmaceutical ingredient and the formulations can meet the specified criteria. In the present monograph, the biowaiver-relevant data including solubility and permeability data, therapeutic use and therapeutic index, pharmacokinetic properties, reported excipient interactions, and BE/bioavailability studies of quinine sulfate are itemized and discussed. Quinine sulfate has borderline solubility characteristics and, on the whole, is highly permeable. Thus, depending on the jurisdiction, it is assigned to Biopharmaceutics Classification System class I or II. Although these characteristics would suggest a low risk of bioinequivalence among oral quinine products, a recent pharmacokinetic study showed bioinequivalence of two products. Even though quinine does not, strictly speaking, fit the definition of a narrow therapeutic index drug, it shows dose-related and, in some cases, irreversible side effects and toxicities at concentrations not far above the therapeutic concentration range. Taking all relevant aspects into consideration, a biowaiver cannot be recommended for new quinine immediate-release multisource products or major post-approval changes of already marketed quinine products, and in such cases, BE should be evaluated using an in vivo BE study.
Oral anticoagulant therapy for stroke prevention in patients with atrial fibrillation undergoing ablation: results from the First European Snapshot Survey on Procedural Routines for Atrial Fibrillation Ablation (ESS-PRAFA).
Potpara, Tatjana S; Larsen, Torben B; Deharo, Jean Claude; Rossvoll, Ole; Dagres, Nikolaos; Todd, Derick; Pison, Laurent; Proclemer, Alessandro; Purefellner, Helmut; Blomström-Lundqvist, Carina
The European Snapshot Survey on Procedural Routines in Atrial Fibrillation Ablation (ESS-PRAFA) is a prospective, multicentre snapshot survey of patients undergoing atrial fibrillation (AF) ablation, conducted to collect patient-based data on current clinical practices in AF ablation in context of the latest AF Guidelines and contemporary oral anticoagulant therapies. The EP Research Network Centres were asked to prospectively enrol consecutive patients during a 6-week period (September/October 2014). Data were collected via the web-based case report form. We present the results pertinent to the use of antithrombotic therapies. Thirteen countries prospectively enrolled 455 eligible consecutive patients [mean age 59 ± 10.8 years, 131 (28.8%) females]. The mean CHA2DS2-VASc score was 1.12 ± 1.06 [137 patients (30.1%) had a score of ≥2]. Before ablation, 443 patients (97.4%) were on anticoagulant therapy [143 (31.4%) on non-vitamin K antagonist oral anticoagulants (NOACs) and 264 (58.0%) on vitamin K antagonists (VKAs)]. Of the latter, 79.7% underwent ablation without VKA interruption, whilst a variety of strategies were used in patients taking NOAC. After ablation, most patients (89.3%) continued the same anticoagulant as before, and 2 (0.4%) were not prescribed any anticoagulation. At discharge, 280 patients (62.2%) were advised oral anticoagulation for a limited period of mean 3.8 ± 2.2 months. On multivariate analysis, CHA2DS2-VASc, AF duration, prior VKA use, and estimated AF ablation success were significantly associated with the decision on short-term anticoagulation. Our results show the increasing use of NOAC in patients undergoing AF ablation and emphasize the need for more information to guide the periprocedural use of both NOACs and VKAs in real-world setting.
Fong, Sophia Yui Kau; Poulsen, Jessie; Brandl, Martin; Bauer-Brandl, Annette
A novel microdialysis-dissolution/permeation (M-D/P) system was developed for the biopharmaceutical assessment of oral drug formulations. This system consists of a side-by-side diffusion chamber, a microdialysis unit fixed within the dissolution chamber for continuous sampling, and a biomimetic Permeapad® as the intestinal barrier. In the M-D/P system, the concentration of the molecularly dissolved drug (with MWCO <20kDa) was measured over time in the dissolution compartment (representing the gastrointestinal tract) while the concentration of the permeated drug was measured in the acceptor compartment (representing the blood). The kinetics of both the dissolution process and the permeation process were simultaneously quantified under circumstances that mimic physiological conditions. For the current proof-of-concept study, hydrocortisone (HCS) in the form of slowly dissolving solvate crystals and buffer and the biorelevant fasted state simulated intestinal fluids (FaSSIF), were employed as the model drug and dissolution media, respectively. The applicability of the M-D/P system to dissolution and permeation profiling of HCS in buffer and in FaSSIF has been successfully demonstrated. Compared to the conventional direct sampling method (using filter of 0.1-0.45μm), sampling by the M-D/P system exhibited distinct advantages, including (1) showing minimal disturbance of the permeation process, (2) differentiating "molecularly" dissolved drugs from "apparently" dissolved drugs during dissolution of HCS in FaSSIF, and (3) being less laborious and having better sampling temporal resolution. M-D/P system appeared to be a promising, simple and routine tool that allows for the researchers' intensive comprehension of the interplay of dissolution and permeation thus helping for better oral formulation screening and as an ultimate goal, for better dosage forms assessment.
A major concern in the management of patients under anticoagulants is the potential for excessive bleeding after dental procedures. Recommendations for the administration of oral anticoagulants in conjunction with oral surgery range from complete withdrawal of anticoagulants to the maintenance of an unchanged therapy. Rising evidences show that the alteration of anticoagulation is not necessary for patients with INR of 4 or less previous to tooth extractions. Topical antifibrinolytics as tranexamic acid control successfully alveolar bleeding. It is time to stop interrupting anticoagulant therapy for oral surgery. A theoretical risk of hemorrhage after dental surgery in patients at therapeutic levels of anticoagulation exists but it is minimal and is greatly overweighed by the risk of thromboembolism after alteration of the anticoagulant therapy.
Dubber, M-J; Kanfer, I
A reversed phase high performance liquid chromatographic method with evaporative light scattering detection (RP-HPLC-ELSD) was developed for the quantitative determination of the terpene trilactones, ginkgolide A, B, C and J and the sesquiterpene, bilobalide in Ginkgo biloba solid oral dosage forms. Separation was achieved using a minibore Phenomenex Luna (5 microm) C18 column with dimensions 250 mm x 2.00 mm maintained at a temperature of 45 degrees C. A simple gradient method using a mobile phase of methanol:water and a flow rate of 350 microl/min facilitated baseline separation of the selected marker compounds within 14 min. The ELSD parameters affecting the detector response were optimized prior to the validation. The limits of detection and quantification were 31.25 and 62.50 ng, respectively. The percentage relative errors of the recovery ranged between -3.16 and +1.88 and both intra-day and inter-day percentage standard deviations were all better than 6%. This method was used to assay commercially available Ginkgo biloba products and proved to be suitable for the routine analysis of such products for quality control purposes.
Funk, Dorothy M Adcock
Anticoagulant therapy, including conventional agents and a variety of new oral, fast-acting drugs, is prescribed for millions of patients annually. Each anticoagulant varies in its effect on routine and specialty coagulation assays and each drug may require distinct laboratory assay(s) to measure drug concentration or activity. This review provides an overview of the assorted assays that can measure anticoagulant drug concentration or activity and includes key assay interferences. The effect of these conventional and new anticoagulant agents on specialty coagulation assays used to evaluate for bleeding or clotting disorders, and whether this impact is physiological or factitious, is included. Also provided is a short review of superwarfarin poisoning and features distinguishing this from warfarin overdose. Knowledge of clinically significant pearls and pitfalls pertinent to coagulation assays in relation to anticoagulant therapy are important to optimize patient care.
Ranmal, Sejal R; Cram, Anne; Tuleu, Catherine
A lack of evidence to guide the design of age-appropriate and acceptable dosage forms has been a longstanding knowledge gap in paediatric formulation development. The Children's Acceptability of Oral Formulations (CALF) study captured end-user perceptions and practices with a focus on solid oral dosage forms, namely tablets, capsules, chewables, orodispersibles, multiparticulates (administered with food) and mini-tablets (administered directly into the mouth). A rigorous development and testing phase produced age-adapted questionnaires as measurement tools with strong evidence of validity and reliability. Overall, 590 school children and adolescents, and 428 adult caregivers were surveyed across hospitals and various community settings. Attitudes towards dosage forms primarily differed based on age and prior use. Positive attitudes to tablets and capsules increased with age until around 14 years. Preference was seen for chewable and orodispersible preparations across ages, while multiparticulates were seemingly less favourable. Overall, 59.6% of school children reported willingness to take 10mm diameter tablets, although only 32.1% of caregivers perceived this size to be suitable. While not to be taken as prescriptive guidance, the results of this study provide some evidence towards rational dosage form design, as well as methodological approaches to help design tools for further evaluation of acceptability within paediatric studies.
Predicting the oral pharmacokinetic profiles of multiple-unit (pellet) dosage forms using a modeling and simulation approach coupled with biorelevant dissolution testing: case example diclofenac sodium.
Kambayashi, Atsushi; Blume, Henning; Dressman, Jennifer B
The objective of this research was to characterize the dissolution profile of a poorly soluble drug, diclofenac, from a commercially available multiple-unit enteric coated dosage form, Diclo-Puren® capsules, and to develop a predictive model for its oral pharmacokinetic profile. The paddle method was used to obtain the dissolution profiles of this dosage form in biorelevant media, with the exposure to simulated gastric conditions being varied in order to simulate the gastric emptying behavior of pellets. A modified Noyes-Whitney theory was subsequently fitted to the dissolution data. A physiologically-based pharmacokinetic (PBPK) model for multiple-unit dosage forms was designed using STELLA® software and coupled with the biorelevant dissolution profiles in order to simulate the plasma concentration profiles of diclofenac from Diclo-Puren® capsule in both the fasted and fed state in humans. Gastric emptying kinetics relevant to multiple-units pellets were incorporated into the PBPK model by setting up a virtual patient population to account for physiological variations in emptying kinetics. Using in vitro biorelevant dissolution coupled with in silico PBPK modeling and simulation it was possible to predict the plasma profile of this multiple-unit formulation of diclofenac after oral administration in both the fasted and fed state. This approach might be useful to predict variability in the plasma profiles for other drugs housed in multiple-unit dosage forms.
Cohen, Alexander T; Imfeld, Stephan; Rider, Thomas
The traditional treatment of venous thromboembolism (VTE) has been use of heparin and vitamin K antagonists (VKA), and although shown to be effective, they have numerous limitations. New oral anticoagulants (NOACs) including direct thrombin (factor IIa) inhibitors (dabigatran) and selective factor Xa inhibitors (rivaroxaban, apixaban and edoxaban) have emerged as promising alternatives with the potential to overcome the limitations of traditional treatments. Clinical trials have been performed with a view to making significant changes to the acute, long-term and extended treatment of VTE. Data are now available on the efficacy and safety, including bleeding rates, of the NOACs in comparison with VKA in the acute treatment and secondary prevention of VTE as well as in comparison with placebo extended VTE treatment. This review compares and contrasts the design and results of the Phase III trials of NOACs in VTE and discusses the implications of the NOACs in terms of treatment strategies in VTE patients.
Watt, Barbara E; Proudfoot, Alex T; Bradberry, Sally M; Vale, J Allister
Anticoagulant pesticides are used widely in agricultural and urban rodent control. The emergence of warfarin-resistant strains of rats led to the introduction of a new group of anticoagulant rodenticides variously referred to as 'superwarfarins', 'single dose' or 'long-acting'. This group includes the second generation 4-hydroxycoumarins brodifacoum, bromadiolone, difenacoum, flocoumafen and the indanedione derivatives chlorophacinone and diphacinone. Most cases of anticoagulant rodenticide exposure involve young children and, as a consequence, the amounts ingested are almost invariably small. In contrast, intentional ingestion of large quantities of long-acting anticoagulant rodenticides may cause anticoagulation for several weeks or months. Occupational exposure has also been reported. Anticoagulant rodenticides inhibit vitamin K(1)-2,3 epoxide reductase and thus the synthesis of vitamin K and subsequently clotting factors II, VII, IX and X. The greater potency and duration of action of long-acting anticoagulant rodenticides is attributed to their: (i) greater affinity for vitamin K(1)-2,3-epoxide reductase; (ii) ability to disrupt the vitamin K(1)-epoxide cycle at more than one point; (iii) hepatic accumulation; and (iv) unusually long biological half-lives due to high lipid solubility and enterohepatic circulation. Substantial ingestion produces epistaxis, gingival bleeding, widespread bruising, haematomas, haematuria with flank pain, menorrhagia, gastrointestinal bleeding, rectal bleeding and haemorrhage into any internal organ; anaemia may result. Spontaneous haemoperitoneum has been described. Severe blood loss may result in hypovolaemic shock, coma and death. The first clinical signs of bleeding may be delayed and patients may remain anticoagulated for several days (warfarin) or days, weeks or months (long-acting anticoagulants) after ingestion of large amounts. There are now sufficient data in young children exposed to anticoagulant rodenticides to
Thambuluru, Sirisha Reddy
Direct oral anticoagulants (DOACs), previously also known as novel oral anticoagulants (NOACs), have increased the therapeutic options for stroke prevention in atrial fibrillation (AF). Previous studies comparing their relative efficacy and safety do not address age-related differences, such as comorbidities and physical and social boundaries. This review aimed to summarize and compare the clinical and safety outcomes of DOACs and warfarin for stroke prevention in AF in the elderly population (≥ 65 years). We searched PubMed for randomized controlled trials and meta-analyses that compared DOACs and warfarin in elderly patients with AF. Stroke and systemic embolism (SSE) and major bleeding (MB) were primary outcomes. Secondary outcomes included ischemic stroke, all-cause mortality, intracranial bleeding, and gastrointestinal bleeding. Of 66 studies identified, one randomized control trial (RCT) and one meta-analysis were included. DOACs were at least as effective at reducing the risk of SSE as warfarin. DOACs demonstrated a minimal benefit for ischemic stroke (dabigatran, 110 mg, relative risk (RR) 1.08; edoxaban, 60 mg, RR 1.00; and apixaban, 5 mg, RR 0.99). DOACs associated with decreased risk of MB relative to warfarin include dabigatran, 110 mg; apixaban, 5 mg; and edoxaban, 60 mg (RR 0.80, 0.70, and 0.80, respectively), while dabigatran, 150 mg, and rivaroxaban, 20 mg, increased risk (RR 0.79 - 0.83, respectively). Dabigatran, 110 mg and 150 mg doses, and edoxaban increased the risk of gastrointestinal bleeding (RR 1.04, 1.12, and 1.23, respectively). Lower rates of SSE and intracranial bleeding were seen with DOACs compared to warfarin. Dabigatran, 150 mg, and rivaroxaban, 20 mg, were associated with higher MB in older elderly compared to warfarin. DOACs may be attractive alternatives to warfarin, but further studies are needed to make clinical recommendations. PMID:27900231
Steinberg, Benjamin A.; Hellkamp, Anne S.; Lokhnygina, Yuliya; Halperin, Jonathan L.; Breithardt, Günter; Passman, Rod; Hankey, Graeme J.; Patel, Manesh R.; Becker, Richard C.; Singer, Daniel E.; Hacke, Werner; Berkowitz, Scott D.; Nessel, Christopher C.; Mahaffey, Kenneth W.; Fox, Keith A.A.; Califf, Robert M.; Piccini, Jonathan P.
Background Antiarrhythmic drugs (AAD) and anticoagulation are mainstays of atrial fibrillation (AF) treatment. Objective We aimed to study the use and outcomes of AAD therapy in anticoagulated AF patients. Methods Patients in the ROCKET AF trial (n=14,264) were grouped by AAD use at baseline: amiodarone, other AAD, or no AAD. Multivariable adjustment was performed to compare stroke, bleeding, and death across groups, as well as across treatment assignment (rivaroxaban or warfarin). Results Of 14,264 patients randomized, 1681 (11.8%) were treated with an AAD (1144 [8%] with amiodarone, 537 [3.8%] with other AADs). Amiodarone-treated patients were less-often female (38% vs. 48%), had more persistent AF (64% vs. 40%), and more concomitant heart failure (71% vs. 41%) than patients receiving other AADs. Patients receiving no AAD more closely-resembled amiodarone-treated patients. Time in therapeutic range was significantly lower in warfarin-treated patients receiving amiodarone versus no AAD (50% vs. 58%, p<0.0001). Compared with no AAD, neither amiodarone (adjusted HR 0.98, 95% CI 0.74–1.31, p=0.9) nor other AADs (adjusted HR 0.66, 95% CI 0.37–1.17, p=0.15) were associated with increased mortality. Similar results were observed for embolic and bleeding outcomes. Rivaroxaban treatment effects in patients not on an AAD were consistent with the overall trial (primary endpoint adjusted HR 0.82, 95% CI 0.68–0.98, pinteraction=0.06; safety endpoint adjusted HR 1.12, 95% CI 0.90–1.24, pinteraction=0.33). Conclusion Treatment with AADs was not associated with increased morbidity or mortality in anticoagulated patients with AF. The influence of amiodarone on outcomes in patients receiving rivaroxaban requires further study. PMID:24833235
Schütze, André; Otter, Rainer; Modick, Hendrik; Langsch, Angelika; Brüning, Thomas; Koch, Holger M
Hexamoll(®) DINCH(®) (diisononyl-cyclohexane-1,2-dicarboxylate) is a new high molecular weight plasticizer and a non-aromatic phthalate substitute. In this follow-up study, we further investigated the extensive oxidative metabolism of Hexamoll(®) DINCH(®) after oral dosage of 50 mg to three male volunteers (0.552-0.606 mg/kg body weight). Urine samples were consecutively collected over 48 h post-dose. Chemical analysis was carried out by HPLC-MS/MS with labeled internal standards. New metabolites were tentatively identified and quantified via fragmentation analogies and new standard substances. In addition to the five urinary DINCH metabolites previously reported by us, we identified two groups of extensively oxidized metabolites characterized (a) by multiple side chain oxidation and breakdown and (b) by hydroxylation at the cyclohexane ring. The five newly identified carboxylated breakdown metabolites represented in sum 5.12 ± 0.49 % of the applied dose. MCHxCH (cyclohexane-1,2-dicarboxylic acid mono carboxyhexyl ester) was identified as a major metabolite (2.71 ± 0.34 %) and thus represents the second most important specific metabolite of DINCH after OH-MINCH (10.7 ± 2.1 %). Less than 1 % was excreted as ring-hydroxylated metabolites (four metabolites identified). Based upon a new reference standard, we can also update oxo-MINCH to 2.6 % of the applied dose. This follow-up study increases the total amount of the recovered dose from 39.2 to 45.7 % and describes a new major metabolite (MCHxCH) of DINCH that can be used as an additional valuable and specific biomarker to assess DINCH(®) exposure in future human biomonitoring studies.
Camm, A John; Pinto, Fausto J; Hankey, Graeme J; Andreotti, Felicita; Hobbs, F D Richard
Stroke is a leading cause of morbidity and mortality worldwide. Atrial fibrillation (AF) is an independent risk factor for stroke, increasing the risk five-fold. Strokes in patients with AF are more likely than other embolic strokes to be fatal or cause severe disability and are associated with higher healthcare costs, but they are also preventable. Current guidelines recommend that all patients with AF who are at risk of stroke should receive anticoagulation. However, despite this guidance, registry data indicate that anticoagulation is still widely underused. With a focus on the 2012 update of the European Society of Cardiology (ESC) guidelines for the management of AF, the Action for Stroke Prevention alliance writing group have identified key reasons for the suboptimal implementation of the guidelines at a global, regional, and local level, with an emphasis on access restrictions to guideline-recommended therapies. Following identification of these barriers, the group has developed an expert consensus on strategies to augment the implementation of current guidelines, including practical, educational, and access-related measures. The potential impact of healthcare quality measures for stroke prevention on guideline implementation is also explored. By providing practical guidance on how to improve implementation of the ESC guidelines, or region-specific modifications of these guidelines, the aim is to reduce the potentially devastating impact that stroke can have on patients, their families and their carers.
Camm, A. John; Pinto, Fausto J.; Hankey, Graeme J.; Andreotti, Felicita; Hobbs, F.D. Richard
Stroke is a leading cause of morbidity and mortality worldwide. Atrial fibrillation (AF) is an independent risk factor for stroke, increasing the risk five-fold. Strokes in patients with AF are more likely than other embolic strokes to be fatal or cause severe disability and are associated with higher healthcare costs, but they are also preventable. Current guidelines recommend that all patients with AF who are at risk of stroke should receive anticoagulation. However, despite this guidance, registry data indicate that anticoagulation is still widely underused. With a focus on the 2012 update of the European Society of Cardiology (ESC) guidelines for the management of AF, the Action for Stroke Prevention alliance writing group have identified key reasons for the suboptimal implementation of the guidelines at a global, regional, and local level, with an emphasis on access restrictions to guideline-recommended therapies. Following identification of these barriers, the group has developed an expert consensus on strategies to augment the implementation of current guidelines, including practical, educational, and access-related measures. The potential impact of healthcare quality measures for stroke prevention on guideline implementation is also explored. By providing practical guidance on how to improve implementation of the ESC guidelines, or region-specific modifications of these guidelines, the aim is to reduce the potentially devastating impact that stroke can have on patients, their families and their carers. PMID:26116685
Differences in attitude, education, and knowledge about oral anticoagulation therapy among patients with atrial fibrillation in Europe: result of a self-assessment patient survey conducted by the European Heart Rhythm Association.
Hernández Madrid, Antonio; Potpara, Tatjana S; Dagres, Nikolaos; Chen, Jian; Larsen, Torben B; Estner, Heidi; Todd, Derick; Bongiorni, Maria G; Sciaraffia, Elena; Proclemer, Alessandro; Cheggour, Saida; Amara, Walid; Blomstrom-Lundqvist, Carina
The purpose of this patient survey was to analyse the knowledge about blood thinning medications relative to gender, age, education, and region of residence in patients with atrial fibrillation (AF). A total of 1147 patients with AF [mean age 66 ± 13 years, 529 (45%) women] from eight European countries responded to this survey. Most patients understood that the indication for anticoagulation therapy was to 'thin the blood', but 8.1% responded that the purpose of the medication was to treat the arrhythmia. Patients with college or university grades reported less frequent deviations from their target INR range compared with those without schooling (2.8% vs. 5.1%, P < 0.05). The awareness of anticoagulation-related risk of bleedings was lowest in patients without schooling (38.5%) and highest in those with college and university education (57.0%), P < 0.05. The same pattern was also observed regarding patient's awareness of non-vitamin K antagonist oral anticoagulants (NOACs): 56.5% of the patients with university education and only 20.5% of those without schooling (P < 0.05) knew about NOACs, indicating that information about new anticoagulation therapies remains well below the target. Bleeding events were statistically less frequent in patients on NOACs compared with vitamin K antagonists. The education level and patients' knowledge have a direct influence on the global management of the anticoagulation.
Içten, Elçin; Giridhar, Arun; Nagy, Zoltan K; Reklaitis, Gintaras V
The features of a drop-on-demand-based system developed for the manufacture of melt-based pharmaceuticals have been previously reported. In this paper, a supervisory control system, which is designed to ensure reproducible production of high quality of melt-based solid oral dosages, is presented. This control system enables the production of individual dosage forms with the desired critical quality attributes: amount of active ingredient and drug morphology by monitoring and controlling critical process parameters, such as drop size and product and process temperatures. The effects of these process parameters on the final product quality are investigated, and the properties of the produced dosage forms characterized using various techniques, such as Raman spectroscopy, optical microscopy, and dissolution testing. A crystallization temperature control strategy, including controlled temperature cycles, is presented to tailor the crystallization behavior of drug deposits and to achieve consistent drug morphology. This control strategy can be used to achieve the desired bioavailability of the drug by mitigating variations in the dissolution profiles. The supervisor control strategy enables the application of the drop-on-demand system to the production of individualized dosage required for personalized drug regimens.
Staudacher, Dawid L.; Kaiser, Michael; Hehrlein, Christoph; Bode, Christoph; Ahrens, Ingo
Antithrombotic therapy consisting of a dual anti-platelet therapy (DAPT) and oral anti-coagulation (OAC) with a vitamin k antagonist is often referred to as triple therapy. This combined anticoagulation is applied in patients undergoing coronary artery stent implantation while also having an indication for OAC. Triple therapy increases the risk for bleeding events compared to either DAPT or OAC alone and thereby might be associated with adverse outcomes. Clinical data on the frequency of bleeding events in patients on triple therapy from clinical trials derives from pre-selected patients and may differ from the real world patients. We report data on patient characteristics and bleeding incidence of patients dismissed on triple therapy from a single university hospital. Within the time span from January 2000 to December 2012, we identified a total of 213 patients undergoing PCI who were prescribed a triple therapy for at least 4 weeks (representing 0.86% of all patients treated). The usage of triple therapy significantly increased over the observed time period. The average CHA2DS2-VASc Score was 3.1 ± 1.1 with an average HAS-BLED score of 2.5 ± 0.86 representing a high-risk group for thromboembolic events as well as considerable risk for bleeding events. An on-treatment bleeding incidence of 9.4% was detected, with gastrointestinal and airway bleeding being the most frequent (5.1% and 1.4%, respectively). This is consistent with data from clinical trials and confirms the high risk of bleeding in patients on DAPT plus OAC. 29.0% of all patients receiving triple therapy had an indication for OAC other than non-valvular atrial fibrillation. This substantial patient group is underrepresented by clinical trials and needs further attention. PMID:26439131
Hermann, Robert; Mungo, Julius; Cnota, Peter Jürgen; Ziegler, Dan
The present study aimed to examine the enantiomer-selective pharmacokinetics (PK), relative bioavailability (Frel), and sex effects of various oral dosage forms of racemic alpha-lipoic acid (ALA). In an open-label, randomized, four-period, four-sequence crossover study, 24 healthy adult subjects (12 males and 12 females) received single doses of 600 mg of ALA in fasted state at four different occasions as follows: three 200 mg tablets (T 200); two 300 mg tablets (T 300); one 600 mg tablet (T 600); and a racemic ALA solution (OS). All tablet formulations (Thioctacid HR) were considered test treatments, while the OS (Thioctacid, 600 T) served as the reference treatment. Serial blood samples were collected over 8 hours postdose to quantify R-(+)- and S-(-)-ALA enantiomer plasma concentrations for the PK evaluation. The maximum observed plasma concentration (Cmax) and total exposure (area under the curve [AUC]0-t) were compared between treatments by analysis of variance. Weight-normalized Cmax and the AUC data of male and female study subjects were applied to examine the presence of sex effects. All treatments displayed rapid absorption of both enantiomers with median time to maximum concentration (tmax) values ranging from 0.33-0.5 hours. The Frel of all tablet formulations was comparable, with R-(+)-enantiomer Cmax test/reference ratios ranging from 36% (T 600) to 43% (T 200), and R-(+)-enantiomer AUC test/reference ratios ranging from 64% (T 600) to 79% (T 300), indicating a favorable Frel of all tablet formulations, especially in terms of the total extent of absorption (AUC). An examination of weight-normalized female/male Cmax and AUC sex ratios for both ALA enantiomers indicated the absence of a significant sex effect for Cmax, as well as 20%-26% and 25%-32% higher R-(+)- and S-(-)-ALA enantiomer AUC outcomes in females when compared to males. The observed modest sex effect was comparable for both ALA enantiomers and across all formulations, and it did not appear
Martí-Fàbregas, J; Delgado-Mederos, R; Mateo, J
Vitamin K antagonists have been shown to be effective in the primary and secondary prevention of systemic and cerebral emboli in patients with cardiac causes of embolism, especially atrial fibrillation. The reduced risk of stroke is greater in secondary prevention, although this reduction is accompanied by an inherent risk of hemorrhagic complications, among which cerebral hemorrhage is especially serious. The therapeutic window of these agents is limited and the best benefit/risk profile is obtained with an INR of between 2 and 3. The anticoagulant effect obtained shows marked variability, requiring frequent clinical and laboratory monitoring of the treatment. The introduction of oral anticoagulants that would aid the administration of these agents with equal or greater efficacy and lower risk is required.
Ball, J H
An understanding of the primary mechanisms of hemostasis, including the coagulation pathways and the intrinsic, extrinsic, and common systems, is the basis for treating the anticoagulated patient. Two major anticoagulants are used for treating those who may be at risk for thromboembolic crisis. These drugs include Coumadin, which is an oral anticoagulant, and heparin, a parenteral anticoagulant, which is often used for acute thromboembolic episodes or for hospitalization protocols that include significant surgical procedures. The practitioner should be familiar with common dental drugs that can interact with anticoagulants and should consult with the patient's physician before administering any such drugs. By placing the patient into one of three dental treatment categories, appropriate anticoagulation therapy can be rendered to each patient according to his or her needs. Low-risk procedures require no change in anticoagulation medication. For moderate-risk procedures, withdrawal of anticoagulation medication 2 days before the procedure and verified with the PT the day of the procedure is indicated. For high-risk dental procedures, using a heparin protocol should be strongly considered. In all instances of dental treatment, the oral tissues should be treated atraumatically using local hemostatic measures for control of hemorrhage. Treating medically compromised patients who are on a variety of medications is becoming more common in dentistry today. Understanding the underlying disease and the appropriate protocol for treatment of anticoagulated patients reduces the risk of thromboembolism and hemorrhagic complications.
Thean, D; Alberghini, M
Several new oral anticoagulants have been studied in the past decade, and have now started to enter the market. These drugs are reported to be as effective as, or more effective than, warfarin. In Australia, the Therapeutic Goods Administration has approved dabigatran, rivaroxaban and apixaban. The use of these newer anticoagulants is likely to increase in time, and it is important for dentists to have a sound understanding of the mechanisms of action, reversal strategies, and management guidelines for patients taking oral anticoagulants. This article discusses the process of coagulation, available anticoagulants and their monitoring and reversal, and provides clinical advice on the management of patients on anticoagulants who require dental treatment.
Lam, Patrick Y S; Clark, Charles G; Li, Renhua; Pinto, Donald J P; Orwat, Michael J; Galemmo, Robert A; Fevig, John M; Teleha, Christopher A; Alexander, Richard S; Smallwood, Angela M; Rossi, Karen A; Wright, Matthew R; Bai, Stephen A; He, Kan; Luettgen, Joseph M; Wong, Pancras C; Knabb, Robert M; Wexler, Ruth R
As part of an ongoing effort to prepare orally active factor Xa inhibitors using structure-based drug design techniques and molecular recognition principles, a systematic study has been performed on the pharmacokinetic profile resulting from replacing the benzamidine in the P1 position with less basic benzamidine mimics or neutral residues. It is demonstrated that lowering the pK(a) of the P1 ligand resulted in compounds (3-benzylamine, 15a; 1-aminoisoquinoline, 24a; 3-aminobenzisoxazole, 23a; 3-phenylcarboxamide, 22b; and 4-methoxyphenyl, 22a) with improved pharmacokinetic features mainly as a result of decreased clearance, increased volume of distribution, and enhanced oral absorption. This work resulted in a series of potent and orally bioavailable factor Xa inhibitors that ultimately led to the discovery of SQ311, 24a. SQ311, which utilizes a 1-aminoisoquinoline as the P1 ligand, inhibits factor Xa with a K(i) of 0.33 nM and demonstrates both good in vivo antithrombotic efficacy and oral bioavailability.
Patel, Sunny; Steen, Dylan
There remains a need for safe, immediately effective, and easy to administer antidotes for patients taking novel oral anticoagulants (NOACs) in the settings of major bleeding, need for emergency surgery, and accidental overdose. We review considerations for the successful safety and effectiveness evaluation of potential antidotes currently under development. These compounds are in expedited regulatory approval programs aimed at accelerating the preclinical and clinical evaluation and approval processes for treatments of serious conditions. We review the features of these expedited programs as well as the FDA's efforts to broadly advance the efficiency of drug development and increase the number of new compounds brought to market. The critical path initiative and regulatory science initiative have resulted in numerous successful programs to address current challenges such as a paucity of validated biomarkers and surrogate endpoints as well as unreliable animal models of toxicity. The FDA has also advocated for increased use of pharmacokinetic/pharmacodynamic modeling and adaptive trial design. These efforts foster collaboration between academia, industry and the public sector across interdisciplinary sciences and may continue to widen the pathway for NOAC-specific reversal agents and other novel compounds.
Raschi, Emanuel; Bianchin, Matteo; Ageno, Walter; De Ponti, Roberto; De Ponti, Fabrizio
Since 2008, the direct-acting oral anticoagulants (DOACs) have expanded the therapeutic options of cardiovascular diseases with recognized clinical and epidemiological impact, such as non-valvular atrial fibrillation (NVAF) and venous thromboembolism (VTE), and also in the preventive setting of orthopedic surgical patients. The large body of evidence, not only from pivotal clinical trials but also from 'real-world' postmarketing observational findings (e.g. analytical epidemiological studies and registry data) gathered to date allow for a first attempt at verifying a posteriori whether or not the pharmacological advantages of the DOACs actually translate into therapeutic innovation, with relevant implications for clinicians, regulators and patients. This review aims to synthesize the risk-benefit profile of DOACs in the aforementioned consolidated indications through an 'evidence summary' approach gathering the existent evidence-based data, particularly systematic reviews with meta-analyses of randomized controlled trials, as well as observational studies, comparing DOACs with vitamin K antagonists. Clinical evidence will be discussed and compared with major international guidelines to identify whether an update is needed. Controversial clinically relevant safety issues will be also examined in order to highlight current challenges and unsettled questions (e.g. actual bleeding risk in susceptible populations). It is anticipated that the large number of publications on NVAF or VTE (44 systematic reviews with meta-analyses and 12 observational studies retained in our analysis) suggests the potential existence of overlapping studies and calls for common criteria to qualitatively and quantitatively assess discordances, thus guiding future research.
Panisello-Tafalla, Anna; Clua-Espuny, Josep Lluís; Gil-Guillen, Vicente F.; González-Henares, Antonia; Queralt-Tomas, María Lluisa; López-Pablo, Carlos; Lucas-Noll, Jorgina; Lechuga-Duran, Iñigo; Ripolles-Vicente, Rosa; Carot-Domenech, Jesús; López, Miquel Gallofré
Objective. This study aimed to examine the effectiveness of the use of oral anticoagulation (OAC) medication, recommended by national guidelines for stroke prevention but reportedly underused in AF patients with moderate to high stroke risk. Method. A multicentre and cross-sectional study of undiagnosed AF among out-of-hospital patients over 60 years old was carried out, visiting 3,638 patients at primary health centres or at home for AF diagnosis using the IDC-10 classification. The main outcome measures were CHA2DS2VASC, HAS-BLED scores, cardiovascular comorbidity, pharmacological information, TTR, and SAMe-TT2R2 scores. Results. The main findings were undiagnosed AF in 26.44% of cases; 31.04% registered with AF but not using OAC despite 95.6% having a CHA2DS2VASC ≥ 2 score; a risk of bleeding in important subgroups using OAC without indication (37.50% CHA2DS2VASC < 2 score); the use of OAC with TTR < 60% (33.1%), of whom 47.6% had a HAS-BLED score ≥3. Thus, 35.4% of the expected AF prevalence achieved an optimal time in the therapeutic range. Conclusions. The expected AF prevalence was 10.9% (n 5267), but the registered prevalence was 7.5% (n 3638). Only 35.04% (CI = 95%, 33.7–36.3) of AF patients treated with vitamin K antagonists (VKAs) achieve the goal of TTR > 60%. PMID:26229954
Proietti, Marco; Cheli, Paola; Basili, Stefania; Mazurek, Michal; Lip, Gregory Y H
Sex and gender differences have been reported in atrial fibrillation (AF), especially in relation to differences in thromboembolic and bleeding risks. More recently, pharmacological treatments have changed following the introduction of non-vitamin K antagonist oral anticoagulants (NOACs) progressively replacing vitamin K antagonists (VKAs). The aims of this systematic review are to summarize the available evidence on NOACs and the relationship to major adverse outcomes according to sex. Moreover, we performed a meta-analysis of data from the phase III clinical trials investigating the sex effect on stroke/systemic embolic events (SEE) and major bleeding. Our literature review found small differences in NOACs efficacy and safety between male and female patients, even if so far available literature is limited to post-hoc ancillary analyses from randomized trials and one cohort study. Meta-analysis from NOAC trials found a differential effect of NOACs, with male patients being more protected from stroke/SEE and female patients more protected from major bleeding events. Further data are needed to fully elucidate sex differences in AF patients treated with NOACs.
Ben Ayed, Hanen; Nasri, Rim; Jemil, Nawel; Ben Amor, Ikram; Gargouri, Jalel; Hmidet, Noomen; Nasri, Moncef
The aim of the present study was to evaluate the acute and sub-chronic toxicity of lipopeptides mixture produced by Bacillus mojavensis A21 as well as their in vitro anticoagulant activity. A21 lipopeptides was given to mice at single dose from 75 mg to 1000 mg/kg body weight (bw). The median lethal dose (LD50) of A21 lipopeptides was about 550 mg/kg bw. Sub-chronic toxicity study for 28 days was done by daily oral administration of A21 lipopeptides at doses of 40 and 400 mg/kg bw in rats. Results showed that A21 lipopeptides did not cause any change in body weights and they did not produce any marked alterations in the hematological blood parameters including hematocrit concentration, hemoglobin level, white and red cells count. However, the platelets level decreased significantly compared to control value. Moreover, no significant differences in the serum biochemical characteristics were observed for rats treated by the lowest dose. In contrast, a little enhancement of alanine-aminotransferase (ALT) activity and decrease in total cholesterol were observed with the highest dose. A21 lipopeptides were also found to cause a prolongation of the thrombin time (TT), the prothrombin time (PT) and the activated partial thromboplastin time (APTT). Overall, A21 lipopeptides may be very promising compounds for therapeutic purposes.
Cohen, A. T.; Hamilton, M.; Bird, A.; Mitchell, S. A.; Li, S.; Horblyuk, R.; Batson, S.
Background Historically, warfarin or aspirin have been the recommended therapeutic options for the extended treatment (>3 months) of VTE. Data from Phase III randomised controlled trials (RCTs) are now available for non-VKA oral anticoagulants (NOACs) in this indication. The current systematic review and network meta-analysis (NMA) were conducted to compare the efficacy and safety of anticoagulants for the extended treatment of VTE. Methods Electronic databases (accessed July 2014 and updated April 2016) were systematically searched to identify RCTs evaluating apixaban, aspirin, dabigatran, edoxaban, rivaroxaban, and warfarin for the extended treatment of VTE. Eligible studies included adults with an objectively confirmed deep vein thrombosis, pulmonary embolism or both. A fixed-effect Bayesian NMA was conducted, and results were presented as relative risks (RRs). Sensitivity analyses examining (i) the dataset employed according to the time frame for outcome assessment (ii) the model used for the NMA were conducted. Results Eleven Phase III RCTs (examining apixaban, aspirin, dabigatran, rivaroxaban, warfarin and placebo) were included. The risk of the composite efficacy outcome (VTE and VTE-related death) was statistically significantly lower with the NOACs and warfarin INR 2.0–3.0 compared with aspirin, with no significant differences between the NOACs. Treatment with apixaban (RR 0.23, 95% CrI 0.10, 0.55) or dabigatran (RR 0.55, 95% Crl 0.43, 0.71) was associated with a statistically significantly reduced risk of ‘major or clinically relevant non-major bleed’ compared with warfarin INR 2.0–3.0. Apixaban also showed a significantly reduced risk compared with dabigatran (RR 0.42, 95% Crl 0.18, 0.97) and rivaroxaban (RR 0.23, 95% Crl 0.09, 0.59). Sensitivity analyses indicate that results were dependent on the dataset, but not on the type of NMA model employed. Conclusions Results from the NMA indicate that NOACs are an effective treatment for prevention of
Nguyen, Louis L.; Brahmanandam, Soma; Bandyk, Dennis F.; Belkin, Michael; Clowes, Alexander W.; Moneta, Gregory L.; Conte, Michael S.
patients without WC (all P < .0001). Conclusions WC is a frequent complication of IB for CLI, associated with increased risk for major amputation, mortality, and greater RU. Further detailed investigation into the link between female gender and oral anticoagulation use with WC may help identify causes of WC and perhaps prevent or lessen their occurrence. PMID:18154995
Sebbag, Lionel; Thomasy, Sara M; Woodward, Andrew P; Knych, Heather K; Maggs, David J
OBJECTIVES To determine, following oral administration of famciclovir, pharmacokinetic (PK) parameters for 2 of its metabolites (penciclovir and BRL42359) in plasma and tears of healthy cats so that famciclovir dosage recommendations for the treatment of herpetic disease can be optimized. ANIMALS 7 male domestic shorthair cats. PROCEDURES In a crossover study, each of 3 doses of famciclovir (30, 40, or 90 mg/kg) was administered every 8 or 12 hours for 3 days. Six cats were randomly assigned to each dosage regimen. Plasma and tear samples were obtained at predetermined times after famciclovir administration. Pharmacokinetic parameters were determined for BRL42359 and penciclovir by compartmental and noncompartmental methods. Pharmacokinetic-pharmacodynamic (PK-PD) indices were determined for penciclovir and compared among all dosage regimens. RESULTS Compared with penciclovir concentrations, BRL42359 concentrations were 5- to 11-fold greater in plasma and 4- to 7-fold greater in tears. Pharmacokinetic parameters and PK-PD indices for the 90 mg/kg regimens were superior to those for the 30 and 40 mg/kg regimens, regardless of dosing frequency. Penciclovir concentrations in tears ranged from 18% to 25% of those in plasma. Administration of 30 or 40 mg/kg every 8 hours achieved penciclovir concentrations likely to be therapeutic in plasma but not in tears. Penciclovir concentrations likely to be therapeutic in tears were achieved only with the two 90 mg/kg regimens. CONCLUSIONS AND CLINICAL RELEVANCE In cats, famciclovir absorption is variable and its metabolism saturable. Conversion of BRL42359 to penciclovir is rate limiting. The recommended dosage of famciclovir is 90 mg/kg every 12 hours for cats infected with feline herpesvirus.
Hanawa, Takehisa; Tokutake, Noboru; Oguchi, Toshio
Elderly patients tend to have troubles with oral conditions such as the impairment of deglutition capability (difficulty in swallowing), in addition to a decline in physical performance. An air extruded jelly formulation (AEJF) has been developed as a new formulation consisting of jelly and clean air under increased pressure. As jelly is discharged smoothly by pushing the air portion, elderly patients are able to easily take jelly from the package. In this study, survey questionnaires after a patient's trial of AEJF were conducted to characterize the intra-oral condition and reveal the applicability of AEJF in elderly patients. The subjects were 108 patients (ranging in age from 50 to 79) with chronic diseases who take some oral medicine regularly. A questionnaire on the oral state and compliance level was conducted before the trial of AEJF. The ratios of subjects with deglutition impairment and dryness of the mouth were 29.7% and 36.1%, respectively. Non-compliance was observed in 31.5% of the subjects. After the trial using AEJF, 94.5% of subjects felt that AEJF was easy to swallow. The ratio of the patients expecting AEJF to be an oral formulation was 89.3%, and those with an intention of daily use was 83.4%. A majority of the subjects, 63.9%, intended to switch their present formulations to AEJF. Especially, a high ratio was found among subjects who presently take a powder formulation or more than 5 kinds of medicines daily. Based on these results, AEJF is expected to improve the adherence of elderly patients to their medicine dosage regimens, and to improve compliance among those with oral troubles or some other hindrance to compliance.
Heit, J A
Common indications for chronic anticoagulation include mechanical prosthetic heart valve, non-rheumatic atrial fibrillation, and venous thromboembolism. Perioperative management of the chronically anticoagulated patient is a complex medical problem, and includes the following issues: urgency of surgery, risk of thromboembolism in the absence of anticoagulation, bleeding risk, consequences of bleeding, ability to control bleeding physically, and duration of bleeding risk after the procedure. Most patients can be managed safely by stopping oral anticoagulants 4-5 days before surgery and restarting anticoagulation after the procedure at the patient's usual daily dose. In general, dental procedures and cataract extraction can be performed without interrupting anticoagulation. Most other procedures can be safely performed with an INR < or = 1.4. For patients with double-wing prosthetic valves (e.g., St. Jude, Carbomedics) in the aortic position, uncomplicated atrial fibrillation, or a remote (>3 months) history of venous thromboembolism, oral anticoagulants can be stopped 4-5 days before surgery and restarted at the usual daily dose immediately after surgery. For other patients at higher risk of thrombosis, "bridging therapy" with outpatient low molecular weight heparin is safe and effective. For urgent procedures, a small dose of oral vitamin K usually will reduce the INR within 24-36 hours to a level sufficient for surgery and avoids exposure to transfused blood products.
Sharma, Manuj; Cornelius, Victoria R; Patel, Jignesh P; Davies, J Graham; Molokhia, Mariam
Background Evidence regarding use of direct oral anticoagulants (DOACs) in the elderly, particularly bleeding risks, is unclear despite the presence of greater comorbidities, polypharmacy and altered pharmacokinetics in this age group. Methods and Results We performed a systematic review and meta-analysis of randomised trials of DOACs (dabigatran, apixaban, rivaroxaban, edoxaban) for efficacy and bleeding outcomes compared to VKA (vitamin k antagonists) in elderly participants (aged ≥75 years) treated for acute venous thromboembolism or stroke prevention in atrial fibrillation. Nineteen studies were eligible for inclusion but only 11 reported data specifically for elderly participants. Efficacy in managing thrombotic risks for each DOAC was similar or superior to VKA in the elderly. A non-significantly, higher risk of major bleeding than VKA was observed with dabigatran 150mg (Odds Ratio 1.18, 95% confidence interval 0.97-1.44) but not with the 110mg dose. Significantly higher gastrointestinal bleeding risks with dabigatran 150mg (1.78, 1.35-2.35) and 110mg (1.40, 1.04-1.90) and lower intracranial bleeding risks than VKA for dabigatran 150mg (0.43, 0.26-0.72) and dabigatran 110mg (0.36, 0.22-0.61) were also observed. A significantly lower major bleeding risk compared to VKA was observed for apixaban (0.63, 0.51-0.77), edoxaban 60mg (0.81, 0.67-0.98) and 30mg (0.46, 0.38-0.57) while rivaroxaban showed similar risk. Conclusion DOACs demonstrated at least equal efficacy to VKA in managing thrombotic risks in the elderly however bleeding patterns were distinct. In particular, dabigatran was associated with a higher risk of gastrointestinal bleeding than VKA. Insufficient published data for apixaban, edoxaban and rivaroxaban indicates further work is needed to clarify their bleeding risks in the elderly. PMID:25995317
Staerk, Laila; Fosbøl, Emil Loldrup; Gadsbøll, Kasper; Sindet-Pedersen, Caroline; Pallisgaard, Jannik Langtved; Lamberts, Morten; Lip, Gregory Y. H.; Torp-Pedersen, Christian; Gislason, Gunnar Hilmar; Olesen, Jonas Bjerring
Among atrial fibrillation (AF) patients, Danish nationwide registries (2011–2015) were used to examine temporal trends of initiation patterns of oral anticoagulation (OAC) treatment according to age. Overall, 43,299 AF patients initiating vitamin K antagonists (VKA) (42%), dabigatran (29%), rivaroxaban (13%), or apixaban (16%) were included with mean age (SD) 72.1 (11.3), 71.5 (11.0), 74.3 (11.1), and 75.3 (11.1) years, respectively. Patients aged ≥85 years comprised 15%. Trend tests showed increase in patients ≥85 years initiating OAC (p < 0.0001). VKA usage decreased from 92% to 24% (p < 0.0001). This decrease was independent of age. Dabigatran was the most common non-VKA OAC (NOAC) (40% users), but usage decreased from 2014 until study end (6%) (p < 0.0001). Apixaban was the most used OAC at study end (41%), in particular among those ≥85 years (44%). Compared with patients aged <65 years, the odds ratios associated with initiating VKA, dabigatran, rivaroxaban, or apixaban for patients aged ≥85 years were 0.81 (95% CI 0.75–0.86), 0.65 (95% CI 0.60–0.70), 1.52 (95% CI 1.38–1.67), and 2.09 (95% CI 1.89–2.30), respectively. In conclusion, substantial increase in NOAC usage has occurred. Increasing age was associated with upstart of rivaroxaban or apixaban with reference to age <65 within the specific agent. PMID:27510920
Alonso-Coello, Pablo; Montori, Victor M; Solà, Ivan; Schünemann, Holger J; Devereaux, Philip J; Charles, Cathy; Roura, Mercè; Díaz, M Gloria; Souto, Juan Carlos; Alonso, Rafael; Oliver, Sven; Ruiz, Rafael; Coll-Vinent, Blanca; Diez, Ana Isabel; Gich, Ignasi; Guyatt, Gordon
Background Oral anticoagulation prevents strokes in patients with atrial fibrillation but, for reasons that remain unclear, less than 40% of all patients with atrial fibrillation receive warfarin. The literature postulates that patient and clinician preferences may explain this low utilization. Design The proposed research seeks to answer the following questions: i) When assessed systematically, do patients' and clinicians' preferences explain the utilization of warfarin to prevent strokes associated with atrial fibrillation? ii) To what extent do patients' and clinicians' treatment preferences differ? iii) What factors explain any differences that exist in treatment preferences between patients and clinicians? To answer these questions we will conduct a two-phase study of patient and clinician preferences for health states and treatments. In the first phase of this study we will conduct structured interviews to determine their treatment preferences for warfarin vs. aspirin to prevent strokes associated with atrial fibrillation using the probability trade-off technique. In the same interview, we will conduct preference-elicitation exercises using the feeling thermometer to identify the utilities that patients place on taking medication (warfarin and aspirin), and on having a mild stroke, a severe stroke, and a major bleed. In the second phase of the study we will convene focus groups of clinicians and patients to explore their answers to the exercises in the first phase. Discussion This is a study of patient and clinician preferences for health states and treatments. Because of its clinical importance and our previous work in this area, we will conduct our study in the clinical context of the decision to use antithrombotic agents to reduce the risk of stroke in patients with non-valvular chronic atrial fibrillation PMID:18954427
Pancholy, Samir B; Sharma, Parikshit S; Pancholy, Dipti S; Patel, Tejas M; Callans, David J; Marchlinski, Francis E
Studies comparing gender-specific outcomes in patients with atrial fibrillation (AF) have reported conflicting results. Gender differences in cerebrovascular accident/systemic embolism (CVA/SE) or major bleeding outcomes with novel oral anticoagulant (NOAC) use are not known. The goal of this analysis was to perform a systematic review and meta-analysis evaluating gender differences in residual risk of CVA/SE and major bleeding outcomes in patients with nonvalvular AF treated with either warfarin or NOAC. Sixty-four randomized studies were identified using keywords "gender," "AF," and "CVA." Using the Preferred Reporting Items for Systemic Reviews and Meta-analysis method, 6 studies met criteria for inclusion in this meta-analysis. CVA/SE and major bleeding outcomes were separately analyzed in cohorts receiving warfarin and NOAC agents, comparing men with women. Women with AF taking warfarin were at a significantly greater residual risk of CVA/SE compared with men (odds ratio 1.279, 95% confidence interval 1.111 to 1.473, Z = -3.428, p = 0.001). No gender difference in residual risk of CVA/SE was noted in patients with AF receiving NOAC agents (odds ratio 1.146, 95% confidence interval 0.97 to 1.354, p = 0.109). Major bleeding was less frequent in women with AF treated with NOAC. In conclusion, women with AF treated with warfarin have a greater residual risk of CVA/SE and an equivalent major bleeding risk, whereas those treated with NOAC agents deemed superior to warfarin are at equivalent residual risk of CVA/SE and less major bleeding risk compared with men. These results suggest an increased net clinical benefit of NOAC agents compared with warfarin in treating women with AF.
Jantratid, Ekarat; De Maio, Vincenzo; Ronda, Emanuela; Mattavelli, Valentina; Vertzoni, Maria; Dressman, Jennifer B
In vitro biorelevant dissolution tests enabling the prediction of in vivo performance of an oral modified-release (MR) dosage form were developed in this study. In vitro dissolution of MR diclofenac sodium pellets containing 100mg active ingredient was evaluated under simulated pre- and postprandial conditions using USP Apparatus 3 (reciprocating cylinder, Bio-Dis) and 4 (flow-through cell) and results compared with compendial methods using USP Apparatus 1 (basket) and 2 (paddle). In vivo, the effects of food on the absorption of diclofenac sodium from the pellet dosage form were investigated by administering the product to 16 healthy volunteers pre- and postprandially in a crossover-design study. The in vitro results were compared with the in vivo data by means of Level A in vitro-in vivo correlation (IVIVC) and Weibull distribution analysis. The compendial dissolution tests were not able to predict food effects. The biorelevant dissolution tests predicted correctly that the release (and hence absorption) of diclofenac sodium would be slower in the fed state than in the fasted state. No significant differences in extent of absorption due to changes in extent of release were predicted or observed. The results demonstrate good correlations between in vitro drug release and in vivo drug absorption in both pre- and postprandial states using the biorelevant dissolution test methods.
Lin, Zhongqiang; Zhou, Deliang; Hoag, Stephen; Qiu, Yihong
Bioequivalence (BE) studies are often required to ensure therapeutic equivalence for major product and manufacturing changes. Waiver of a BE study (biowaiver) is highly desired for such changes. Current regulatory guidelines allow for biowaiver of proportionally similar lower strengths of an extended release (ER) product provided it exhibits similar dissolution to the higher strength in multimedia. The objective of this study is to demonstrate that (1) proportionally similar strengths of ER tablets exhibiting similar in vitro dissolution profiles do not always assure BE and (2) different strengths that do not meet the criteria for dissolution profile similarity may still be bioequivalent. Four marketed ER tablets were used as model drug products. Higher and lower (half) strength tablets were prepared or obtained from commercial source. In vitro drug release was compared using multi-pH media (pH 1.2, 4.5, 6.8) per regulatory guidance. In vivo performance was assessed based on the available in vivo BE data or established in vitro-in vivo relationships. This study demonstrated that the relationship between in vitro dissolution and in vivo performance is complex and dependent on the characteristics of specific drug molecules, product design, and in vitro test conditions. As a result, proportionally similar strengths of ER dosage forms that meet biowaiver requirements per current regulatory guidelines cannot ensure bioequivalence in all cases. Thus, without an established relationship between in vitro and in vivo performance, granting biowaiver based on passing in vitro tests may result in the approval of certain bioinequivalent products, presenting risks to patients. To justify any biowaiver using in vitro test, it is essential to understand the effects of drug properties, formulation design, product characteristics, test method, and its in vivo relevance. Therefore, biowaiver requirements of different strengths of ER dosage forms specified in the current regulatory
Tripodi, A; Chantarangkul, V; Clerici, M; Negri, B; Mannucci, P M
A key issue for the reliable use of new devices for the laboratory control of oral anticoagulant therapy with the INR is their conformity to the calibration model. In the past, their adequacy has mostly been assessed empirically without reference to the calibration model and the use of International Reference Preparations (IRP) for thromboplastin. In this study we reviewed the requirements to be fulfilled and applied them to the calibration of a new near-patient testing device (TAS, Cardiovascular Diagnostics) which uses thromboplastin-containing test cards for determination of the INR. On each of 10 working days citrated whole blood and plasma samples were obtained from 2 healthy subjects and 6 patients on oral anticoagulants. PT testing on whole blood and plasma was done with the TAS and parallel testing for plasma by the manual technique with the IRP CRM 149S. Conformity to the calibration model was judged satisfactory if the following requirements were met: (i) there was a linear relationship between paired log-PTs (TAS vs CRM 149S); (ii) the regression line drawn through patients data points, passed through those of normals; (iii) the precision of the calibration expressed as the CV of the slope was <3%. A good linear relationship was observed for calibration plots for plasma and whole blood (r = 0.98). Regression lines drawn through patients data points, passed through those of normals. The CVs of the slope were in both cases 2.2% and the ISIs were 0.965 and 1.000 for whole blood and plasma. In conclusion, our study shows that near-patient testing devices can be considered reliable tools to measure INR in patients on oral anticoagulants and provides guidelines for their evaluation.
Barnes, Geoffrey D; Kline-Rogers, Eva
Anticoagulants are highly effective at preventing thrombosis across a variety of clinical indications. However, their use can also lead to devastating effects, including major bleeding and death. Anticoagulation providers strive to balance the benefits of anticoagulant therapy with the risks of major bleeding. A measure of quality care can be used to assess the strengths and potential weaknesses in any system of coordinated care delivery. Quality measures in anticoagulation include patient-centered outcomes (e.g. major bleeding, time in the therapeutic range) and provider- or process-focused outcomes (e.g. compliance with guideline recommendations and response times to out-of-range laboratory values). Engaging in quality improvement activities allows anticoagulation providers to assess their own performance and identify areas for targeted interventions. This review summarizes the justification for engaging in quality improvement for anticoagulation management and describes a number of example programs. Interventions benefiting the management of both warfarin and the direct oral anticoagulants are included. The review also details potential quality measures and resources for any anticoagulation provider looking to begin a quality improvement process.
Barnes, Geoffrey D.; Kline-Rogers, Eva
Anticoagulants are highly effective at preventing thrombosis across a variety of clinical indications. However, their use can also lead to devastating effects, including major bleeding and death. Anticoagulation providers strive to balance the benefits of anticoagulant therapy with the risks of major bleeding. A measure of quality care can be used to assess the strengths and potential weaknesses in any system of coordinated care delivery. Quality measures in anticoagulation include patient-centered outcomes (e.g. major bleeding, time in the therapeutic range) and provider- or process-focused outcomes (e.g. compliance with guideline recommendations and response times to out-of-range laboratory values). Engaging in quality improvement activities allows anticoagulation providers to assess their own performance and identify areas for targeted interventions. This review summarizes the justification for engaging in quality improvement for anticoagulation management and describes a number of example programs. Interventions benefiting the management of both warfarin and the direct oral anticoagulants are included. The review also details potential quality measures and resources for any anticoagulation provider looking to begin a quality improvement process. PMID:25772116
Efficiency and effectiveness of the use of an acenocoumarol pharmacogenetic dosing algorithm versus usual care in patients with venous thromboembolic disease initiating oral anticoagulation: study protocol for a randomized controlled trial
Background Hemorrhagic events are frequent in patients on treatment with antivitamin-K oral anticoagulants due to their narrow therapeutic margin. Studies performed with acenocoumarol have shown the relationship between demographic, clinical and genotypic variants and the response to these drugs. Once the influence of these genetic and clinical factors on the dose of acenocoumarol needed to maintain a stable international normalized ratio (INR) has been demonstrated, new strategies need to be developed to predict the appropriate doses of this drug. Several pharmacogenetic algorithms have been developed for warfarin, but only three have been developed for acenocoumarol. After the development of a pharmacogenetic algorithm, the obvious next step is to demonstrate its effectiveness and utility by means of a randomized controlled trial. The aim of this study is to evaluate the effectiveness and efficiency of an acenocoumarol dosing algorithm developed by our group which includes demographic, clinical and pharmacogenetic variables (VKORC1, CYP2C9, CYP4F2 and ApoE) in patients with venous thromboembolism (VTE). Methods and design This is a multicenter, single blind, randomized controlled clinical trial. The protocol has been approved by La Paz University Hospital Research Ethics Committee and by the Spanish Drug Agency. Two hundred and forty patients with VTE in which oral anticoagulant therapy is indicated will be included. Randomization (case/control 1:1) will be stratified by center. Acenocoumarol dose in the control group will be scheduled and adjusted following common clinical practice; in the experimental arm dosing will be following an individualized algorithm developed and validated by our group. Patients will be followed for three months. The main endpoints are: 1) Percentage of patients with INR within the therapeutic range on day seven after initiation of oral anticoagulant therapy; 2) Time from the start of oral anticoagulant treatment to achievement of a
Carr, M M; Mason, R B
Today's trend toward ambulatory medical care will bring more pharmacological problems into the dental office. While the dental management of patients taking oral anticoagulants is controversial, current research supports the contention that they can be safely treated on an outpatient basis. The use of the International Normalized Ratio (INR) has made better estimates of prothrombin time possible, and patients can be maintained in a narrow therapeutic range. Postoperative hemorrhage can be avoided or controlled with local hemostatic agents.
Point-of-care monitoring of oral anticoagulation therapy in children. Comparison of the CoaguChek XS system with venous INR and venous INR using an International Reference Thromboplastin preparation (rTF/95).
Greenway, Anthea; Ignjatovic, Vera; Summerhayes, Robyn; Newall, Fiona; Burgess, Janet; DeRosa, Lydia; Monagle, Paul
Point-of-care (POC) monitoring of oral anticoagulation has been widely adopted in both paediatric and adult patients. A new POC system, the CoaguChek XS has recently been developed to measure the international normalised ratio (INR) and may offer significant advantages. The CoaguChek XS utilises a new method of electrochemical clot detection based on thrombin generation. This system has not been previously evaluated in children with reference to the laboratory gold standard, the prothrombin time using reference thromboplastin. It was the objective to compare values obtained by the CoaguChek XS system with both the venous INR and the gold standard for anticoagulant monitoring, prothrombin time with reference thromboplastin (rTF/95). To evaluate the impact of testing using the CoaguChek XS on clinical anticoagulant dosing decisions. Fifty paired venous INR and capillary CoaguChek XS results were obtained from 31 children (aged up to 16 years). The laboratory gold standard, a manual prothrombin time with reference thromboplastin (rTF/95) was additionally performed on 26 samples. Correlation between the CoaguChek XS result and the venous INR was r = 0.810. Agreement between the CoaguChek XS result and the reference INR was shown to be higher (r=0.95), in the subset analysed by this method. Correlation between the venous INR and reference INR was r=0.90. Despite changes to the methodology of testing with the CoaguChek XS POC monitoring system, the accuracy of this method when compared with both the venous INR and gold standard reference INR was satisfactory. This resulted in infrequent changes to clinical decision making regarding anticoagulation.
Gómez-Outes, Antonio; Suárez-Gea, M Luisa; Lecumberri, Ramón; Terleira-Fernández, Ana Isabel; Vargas-Castrillón, Emilio
Pulmonary embolism (PE) is a relatively common cardiovascular emergency. PE and deep vein thrombosis (DVT) are considered expressions of the same disease, termed as venous thromboembolism (VTE). In the present review, we describe and meta-analyze the efficacy and safety data available with the direct oral anticoagulants (DOAC; dabigatran, rivaroxaban, apixaban, edoxaban) in clinical trials testing these new compounds in the acute/long-term and extended therapy of VTE, providing subgroup analyses in patients with index PE. We analyzed ten studies in 35,019 randomized patients. A total of 14,364 patients (41%) had index PE. In the acute/long-term treatment of VTE, the DOAC showed comparable efficacy in preventing recurrent VTE to standard treatment in patients with index PE (risk ratio [RR]: 0.88; 95% confidence interval [CI]: 0.70-1.11) and index DVT (RR: 0.93; 95% CI: 0.75-1.16) (P for subgroup differences =0.76). VTE recurrence depending on PE anatomical extension and presence/absence of right ventricular dysfunction was only reported in two trials, with results being consistent with those obtained in the overall study populations. In the single trial comparing extended therapy of VTE with DOAC versus warfarin, the point estimate for recurrent VTE tended to disfavor the DOAC in patients with index PE (RR: 2.05; 95% CI: 0.83-5.03) and in patients with index DVT (RR: 1.11; 95% CI: 0.49-2.50) (P for subgroup differences =0.32). In trials that compared DOAC versus placebo for extended therapy, the reduction in recurrent VTE was consistent in patients with PE (RR: 0.15; 95% CI: 0.01-1.82) and in patients with DVT (RR: 0.25; 95% CI: 0.10-0.61) (P for subgroup differences =0.71). The DOAC were associated with a consistently lower risk of clinically relevant bleeding (CRB) than standard treatment of acute VTE and higher risk of CRB than placebo for extended therapy of VTE regardless of index event. In summary, the DOAC were as effective as, and safer than, standard
Gómez-Outes, Antonio; Suárez-Gea, Mª Luisa; Lecumberri, Ramón; Terleira-Fernández, Ana Isabel; Vargas-Castrillón, Emilio
Pulmonary embolism (PE) is a relatively common cardiovascular emergency. PE and deep vein thrombosis (DVT) are considered expressions of the same disease, termed as venous thromboembolism (VTE). In the present review, we describe and meta-analyze the efficacy and safety data available with the direct oral anticoagulants (DOAC; dabigatran, rivaroxaban, apixaban, edoxaban) in clinical trials testing these new compounds in the acute/long-term and extended therapy of VTE, providing subgroup analyses in patients with index PE. We analyzed ten studies in 35,019 randomized patients. A total of 14,364 patients (41%) had index PE. In the acute/long-term treatment of VTE, the DOAC showed comparable efficacy in preventing recurrent VTE to standard treatment in patients with index PE (risk ratio [RR]: 0.88; 95% confidence interval [CI]: 0.70–1.11) and index DVT (RR: 0.93; 95% CI: 0.75–1.16) (P for subgroup differences =0.76). VTE recurrence depending on PE anatomical extension and presence/absence of right ventricular dysfunction was only reported in two trials, with results being consistent with those obtained in the overall study populations. In the single trial comparing extended therapy of VTE with DOAC versus warfarin, the point estimate for recurrent VTE tended to disfavor the DOAC in patients with index PE (RR: 2.05; 95% CI: 0.83–5.03) and in patients with index DVT (RR: 1.11; 95% CI: 0.49–2.50) (P for subgroup differences =0.32). In trials that compared DOAC versus placebo for extended therapy, the reduction in recurrent VTE was consistent in patients with PE (RR: 0.15; 95% CI: 0.01–1.82) and in patients with DVT (RR: 0.25; 95% CI: 0.10–0.61) (P for subgroup differences =0.71). The DOAC were associated with a consistently lower risk of clinically relevant bleeding (CRB) than standard treatment of acute VTE and higher risk of CRB than placebo for extended therapy of VTE regardless of index event. In summary, the DOAC were as effective as, and safer than
Background Managing oral anticoagulant treatment (OAT) is a challenge for patients and primary care providers. It requires a high level of patient knowledge and adherence. Studies have shown that insufficient adherence and a low level of patient knowledge about OAT are primary causes for complications. This trial is the first to evaluate the long-term effects of a complex practice nurse-based patient education program in comparison to a patient brochure only. Methods and design This trial will be a cluster-randomized controlled trial in 22 general practices (GPs) recruiting 360 patients with OAT. GPs will be randomized into an intervention group or a control group. A baseline questionnaire will assess pre-existing knowledge about OAT. The patients in the intervention group will be educated by a complex education program which consists of a video, a brochure and individual training by a practice nurse. The video gives information about OAT, nutrition, and instructions about how to manage critical situations. The brochure repeats the content of the video. After 4 to 6 weeks, the intervention will be recapitulated. The control group will receive the brochure only. After 6 months, questionnaires will be used in both groups to assess patient knowledge about OAT as well as patients' subjective feelings of safety. Separately, we will evaluate patient records, looking for documented complications and the time spent in the therapeutic range. Discussion This trial will start in January 2011. This trial will evaluate the long-term effectiveness of a video-assisted education program on patients with OAT in comparison to a patient information brochure. Most previous studies have evaluated knowledge directly after an educational intervention. Our trial will look for long-term differences in basic knowledge of OAT. We expect that our complex patient education program effectively increases long-term basic knowledge about OAT. Although the population of our study is too small to
Mohammed, Noorullah Naqvi; Majumdar, Soumyajit; Singh, Abhilasha; Deng, Weibin; Murthy, Narasimha S; Pinto, Elanor; Tewari, Divya; Durig, Thomas; Repka, Michael A
The objective of this research work was to evaluate Klucel™ hydroxypropylcellulose (HPC) EF and ELF polymers, for solubility enhancement as well as to address some of the disadvantages associated with solid dispersions. Ketoprofen (KPR), a Biopharmaceutics Classification System class II drug with poor solubility, was utilized as a model compound. Preliminary thermal studies were performed to confirm formation of a solid solution/dispersion of KPR in HPC matrix and also to establish processing conditions for hot-melt extrusion. Extrudates pelletized and filled into capsules exhibited a carrier-dependent release with ELF polymer exhibiting a faster release. Tablets compressed from milled extrudates exhibited rapid release owing to the increased surface area of the milled extrudate. Addition of mannitol (MNT) further enhanced the release by forming micro-pores and increasing the porosity of the extrudates. An optimized tablet formulation constituting KPR, MNT, and ELF in a 1:1:1 ratio exhibited 90% release in 15 min similar to a commercial capsule formulation. HPC polymers are non-ionic hydrophilic polymers that undergo polymer-chain-length-dependent solubilization and can be used to enhance solubility or dissolution rate of poorly soluble drugs. Dissolution/release rate could be tailored for rapid-release applications by selecting a suitable HPC polymer and altering the final dosage form. The release obtained from pellets was carrier-dependent and not drug-dependent, and hence, such a system can be effectively utilized to address solubility or precipitation issues with poorly soluble drugs in the gastrointestinal environment.
Fujii, Yoshimine; Kanamaru, Taro; Kikuchi, Hiroshi; Nakagami, Hiroaki; Yamashita, Shinji; Akashi, Mitsuru; Sakuma, Shinji
A clinical trial of (2S)-2-[4-[[(3S)-1-acetimidoyl-3-pyrrolidinyl]oxy]phenyl]-3-(7-amidino-2-naphtyl) propanoic acid (DX-9065) revealed that its oral bioavailability was only 3% when it was administered as a conventional capsule formulation. The low bioavailability of DX-9065 was likely caused by both its poor membrane permeability and its electrostatic interaction with anionic bile acids. We hypothesized that DX-9065 absorption would be enhanced when the cationic drug was free from the complex through its replacement with other cationic substances. Polystyrene nanospheres coated with cationic poly(vinylamine) and cholestyramine, which is clinically used as a cholesterol-lowering agent, dramatically prevented DX-9065 from interacting with chenodeoxycholic acid in vitro. Successive animal experiments showed that bioavailability of DX-9065 administered with these cationic substances was 2-3 times that of DX-9065 administered solely. A dry syrup formulation with one-half of a minimal cholesterol-lowering equivalent dose of cholestyramine was designed, and the clinical trial was resumed. A 1.3-fold increase in bioavailability of DX-9065 was observed when the dry syrup was administered. We successfully demonstrated that DX-9065 absorption was enhanced when the drug was administered with cationic additives; however, it appeared that the absorption-enhancing function of cholestyramine largely depended on its dose. The dose escalation is probably prerequisite for the significant improvement of DX-9065 absorption in humans.
Antithrombotic therapy use in patients with atrial fibrillation before the era of non-vitamin K antagonist oral anticoagulants: the Global Registry on Long-Term Oral Antithrombotic Treatment in Patients with Atrial Fibrillation (GLORIA-AF) Phase I cohort
Huisman, Menno V.; Ma, Chang Sheng; Diener, Hans-Christoph; Dubner, Sergio J.; Halperin, Jonathan L.; Rothman, Kenneth J.; Teutsch, Christine; Schoof, Nils; Kleine, Eva; Bartels, Dorothee B.; Lip, Gregory Y.H.
Aims The introduction of non-VKA oral anticoagulants (NOACs), which differ from the earlier vitamin K antagonist (VKA) treatments, has changed the approach to stroke prevention in atrial fibrillation (AF). GLORIA-AF is a prospective, global registry programme describing the selection of antithrombotic treatment in newly diagnosed AF patients at risk of stroke. It comprises three phases: Phase I, before the introduction of NOACs; Phase II, during the time of the introduction of dabigatran, the first NOAC; and Phase III, once NOACs have been established in clinical practice. Methods and results In Phase I, 1063 patients were eligible from the 1100 enrolled (54.3% male; median age 70 years); patients were from China (67.1%), Europe (EU; 27.4%), and the Middle East (ME; 5.6%). The majority of patients using VKAs had high stroke risk (CHA2DS2-VASc ≥ 2; 86.5%); 13.5% had moderate risk (CHA2DS2-VASc = 1). Vitamin K antagonist use was higher for persistent/permanent AF (47.7%) than that for paroxysmal (23.9%). Most patients in China were treated with antiplatelet agents (53.7%) vs. 27.1% in EU and 28.8% in ME. In China, 25.9% of patients had no antithrombotic therapy, vs. 8.6% in EU and 8.5% in ME. Conclusion Phase I of GLORIA-AF shows that VKAs were mostly used in patients with persistent/permanent (vs. paroxysmal) AF and in those with high stroke risk. Furthermore, there were meaningful geographical differences in the use of VKA therapy in the era before the availability of NOACs, including a much lower use of VKAs in China, where most patients either received antiplatelet agents or no antithrombotic treatment. PMID:27335063
Almeida, A; Possemiers, S; Boone, M N; De Beer, T; Quinten, T; Van Hoorebeke, L; Remon, J P; Vervaet, C
Different ethylene vinyl acetate grades (EVA9, EVA15, EVA28 and EVA40 having a VA content of 9%, 15%, 28% and 40%, respectively) were characterized via differential scanning calorimetry. Glass transition temperature (T(g)), polymer crystallinity, melting point and polymer flexibility were positively influenced by the vinyl acetate content. The processability of EVA-based formulations produced by means of hot-melt extrusion (2mm die) was evaluated in function of VA content, extrusion temperature (60-140°C) and metoprolol tartrate (MPT, used as model drug) concentration (10-60%). Matrices containing 50% MPT resulted in smooth-surfaced extrudates, whereas at 60% drug content severe surface defects (shark skinning) were observed. Drug release from EVA/MPT matrices (50/50, w/w) was affected by the EVA grades: 90% after 24h for EVA15 and 28, while EVA9 and EVA40 formulations released 80% and 60%, respectively. Drug release also depended on drug loading and extrusion temperature. For all systems, the total matrix porosity (measured by X-ray tomography) was decreased after dissolution due to elastic rearrangement of the polymer. However, the largest porosity reduction was observed for EVA40 matrices as partial melting of the structure (melt onset temperature: 34.7°C) also contributed (thereby reducing the drug release pathway and yielding the lowest release rate from EVA40 formulations). The Simulator of the Human Intestinal Microbial Ecosystem (SHIME) used to evaluate the stability of EVA during gastrointestinal transit showed that EVA was not modified during GI transit, nor did it affect the GI ecosystem following oral administration.
Ouwendijk, R J; Koster, J C; Wilson, J H; Stibbe, J; Lameris, J S; Visser, W; Benhamou, J P
The case of a 20 year old woman is reported with Budd-Chiari syndrome in whom lupus anticoagulant and anticardiolipin antibodies were shown; treatment with oral anticoagulants induced a considerable improvement. This treatment was interrupted after one year; interruption was followed by redevelopment of ascites. Further treatment with anticoagulants was continued for five years with noticeable improvement. When treatment with oral anticoagulants was stopped because of pregnancy, the patient redeveloped ascites and had a spontaneous miscarriage. Subsequently, treatment with oral anticoagulants was reintroduced and again resulted in noticeable improvement. In conclusion patients with Budd-Chiari syndrome should be tested for lupus anticoagulants and anticardiolipin antibodies, Budd-Chiari syndrome resulting from this cause may have a good response to treatment with oral anticoagulants; this treatment should be maintained permanently, and pregnancy in such patients may initiate serious difficulties. Images p1004-a PMID:8063206
Simultaneous administration of the anticoagulants acenocoumarol, phenprocoumon or chlorindion and the antirheumatic substance alclofenac in long term trials has no observable influence on the prothrombin time of stabilized patients. When the anticoagulant (acenocoumarol or phenprocoumon) and the alclofenac therapy are begun simultaneously, a variation of the dose is necessary. Either a one-third lower initial dosage can be given, or, after attaining the maximal anticoagulation effect on the prothrombin time (48 h after beginning acenocoumarol therapy, 72 h with phenprocoumarol), a lower daily dosage must be administered once, in comparison to the other group without alclofenac therapy. The maintenace dosage is not influenced by alclofenac.
Herman, W W; Konzelman, J L; Sutley, S H
Despite approximately 40 years of experience with oral anticoagulant drugs, controversy still exists about the safety of dental treatment in a patient receiving this therapy. The authors review the topic in depth and offer detailed recommendations for the dental management of patients receiving coumarin anticoagulant therapy.
Johnson, Michelle E; Lefèvre, Cinira; Collings, Shuk-Li; Evans, David; Kloss, Sebastian; Ridha, Essra; Maguire, Andrew
Objectives To examine the characteristics and persistence in patients newly initiated with oral anticoagulants (OACs) for stroke prevention in non-valvular atrial fibrillation (NVAF). Design Cohort study in Clinical Practice Research Datalink. Setting UK primary care. Participants 15 242 patients with NVAF newly prescribed apixaban, rivaroxaban, dabigatran or vitamin K antagonists (VKAs) between 1 December 2012 and 31 October 2014. 13 089 patients were OAC naïve. Outcome measures Patient characteristics and risk of non-persistence compared to apixaban using Cox regression models over the entire follow-up and using a time-partitioned approach to handle non-proportional hazards. Results Among the OAC naïve patients, VKAs were most common (78.1%, n=10 218), followed by rivaroxaban (12.1%, n=1589), dabigatran (5.7%, n=741) and apixaban (4.1%, n=541). High baseline stroke risk (CHA2DS2VASc ≥2) ranged from 80.2% (dabigatran) to 88.4% (apixaban and rivaroxaban). History of stroke and bleeding was the highest among apixaban (23.7% and 31.6%) and lowest among VKA patients (15.9% and 27.5%). Across the entire follow-up period, adjusting for differences in characteristics, there was no evidence of a difference in non-persistence between VKA and apixaban (HR 0.92 (95% CI 0.68 to 1.23)). Non-persistence was higher with dabigatran (HR 1.67 (1.20 to 2.32)) and rivaroxaban (HR 1.41 (1.02 to 1.93)) than apixaban. Using the partitioned approach, non-persistence was lower with VKA (HR 0.33 (0.22 to 0.48)), and higher with dabigatran (HR 1.65 (1.08 to 2.52)) compared to apixaban in the first 2 months of follow-up. After 2 months, non-persistence was higher with VKA (HR 1.70 (1.08 to 2.66)) and dabigatran (HR 2.10 (1.30 to 3.41)). Pooling OAC naïve and experienced patients, non-persistence was also higher with rivaroxaban compared to apixaban after 2 months of follow-up (HR 1.69 (1.19 to 2.39)). Conclusions Observed differential prescribing of OACs can result in
Tshikudi, Diane M.; Tripathi, Markandey M.; Hajjarian, Zeinab; Nadkarni, Seemantini K.
Defective blood coagulation resulting from excessive procoagulant activity often leads to thrombotic disorders such as stroke and myocardial infarction. A variety of oral and injectable anticoagulant drugs are prescribed to prevent or treat life-threatening thrombosis. However, due to bleeding complications often associated with anticoagulant treatment, routine monitoring and accurate dosing of anticoagulant therapy is imperative. We have developed Optical thromboelastography (OTEG), a non-contact approach that utilizes a drop of whole blood to measure blood coagulation status in patients. Here, we demonstrate the capability of OTEG for rapidly monitoring anticoagulation in whole blood samples. OTEG monitors coagulation status by assessing changes in blood viscosity from temporal intensity fluctuations of laser speckle patterns during clotting. In OTEG a blood drop is illuminated with coherent light and the blood viscosity is measured from the speckle intensity autocorrelation curve, g2 (t). The metrics, clotting time (R+k), clot progression (angle) and maximum clot stiffness (MA) are then extracted. The aim of the current study was to evaluate the accuracy of OTEG in assessing anticoagulation status of common anticoagulants including heparin, argatroban and rivaroxaban status. A dose-dependent prolongation of R+k was observed in anticoagulated blood, which closely corresponded with standard-reference Thromboelastography (TEG) (r 0.87-0.99, P>0.01 for all cases). OTEG angle was unaltered by anticoagulation whereas TEG angle presented a dose-dependent diminution probably linked to clot rupture. In both OTEG and TEG, MA was unaffected by heparin, argatroban or rivaroxaban. We conclude that OTEG can accurately monitor anticoagulation status following treatment, potentially providing a powerful tool for routine monitoring of patients in the doctor's office or in the home setting.
Dilute Russell's viper venom (DRVV) testing and activated partial thromboplastin time (APTT) have been effectively used in combination for lupus anticoagulant testing. The purpose of our study was to evaluate the role of mixing in activated partial thromboplastin and dilute Russell's viper venom testing for evaluation of lupus anticoagulants. Citrated blood from patients who were not on oral anticoagulant therapy was studied. Mixing study with 1 : 1 normal plasma for elevated APTT and also few samples with elevated screen time was carried out. Elevated APTT was seen in only 48.1% of patients with lupus anticoagulant. Correction of APTT was seen in 27.8% of lupus anticoagulant-positive patients. DRVV test on mixing resulted in 83.8% false-negative values. Integrated DRVV test could be a standalone test for testing lupus anticoagulant. Mixing study may be restricted for patients on oral anticoagulants or patients with strong lupus anticoagulant.
Shaikh, Safiya Imtiaz; Kumari, R. Vasantha; Hegade, Ganapati; Marutheesh, M.
Anticoagulants remain the primary strategy for the prevention and treatment of thrombosis. Unfractionated heparin, low molecular weight heparin (LMWH), fondaparinux, and warfarin have been studied and employed extensively with direct thrombin inhibitors typically reserved for patients with complications or those requiring interventions. Novel oral anticoagulants have emerged from clinical development and are expected to replace older agents with their ease to use and more favorable pharmacodynamic profiles. Increasingly, anesthesiologists are being requested to anesthetize patients who are on some form of anticoagulants and hence it is important to have sound understanding of pharmacology, dosing, monitoring, and toxicity of anticoagulants. We searched the online databases including PubMed Central, Cochrane, and Google Scholar using anticoagulants, perioperative management, anesthetic considerations, and LMWH as keywords for the articles published between 1994 and 2015 while writing this review. In this article, we will review the different classes of anticoagulants and how to manage them in the perioperative settings. PMID:28298749
Parekh, Parth J; Merrell, Jonathan; Clary, Meredith; Brush, John E; Johnson, David A
The discovery of the first oral anticoagulant, warfarin, was a milestone in anticoagulation. Warfarin's well-known limitations, however, have led to the recent development of more effective anticoagulants. The rapidly growing list of these drugs, however, presents a challenge to endoscopists who must treat patients on these sundry medications. This review is intended to summarize the pharmacological highlights of new anticoagulants, with particular attention to suggested "best-practice" recommendations for the withholding of these drugs before endoscopic procedures.
Nair, V D P; Kanfer, I; Hoogmartens, J
A validated and repeatable high performance liquid chromatography (HPLC) method with online evaporative light scattering (ELSD) was developed for the analysis of two sterols, stigmasterol, beta-sitosterol and a stanol, stigmastanol, found to be common in many herbal formulations and health care supplements. The method is based on the separation of the three marker compounds on a C8 column (Phenomenex Luna, 5 microm, 150 mmx4.6 mm i.d.) using methanol:water (95:5 v/v) as the mobile phase, and a flow rate of 1 ml/min to separate all the marker compounds within 12 min. Cholesterol (50 microg/ml) was used as internal standard and methanol as the extraction solvent. The ELSD response parameters were optimised and the limits of detection (LOD) and quantification (LOQ) were calculated to be 2 and 5 microg/ml, respectively, which is more sensitive than obtained by photo diode array detection (5 and 7 microg/ml). Using ELSD, the percentage relative standard deviation (%R.S.D.) of intra-day and inter-day (3 days) precision for each marker was better than 3%, the accuracy data were within 97-103% and the recovery data were found to be within 95-107% for the five commercially available products examined. This method was used to assay commercially available products formulated as oral dosage forms purported to contain African Potato and associated sterols and stanol and proved to be suitable for the routine analysis and quality control of such products.
Sanfélix-Gimeno, G; Rodríguez-Bernal, C L; Hurtado, I; Baixáuli-Pérez, C; Librero, J; Peiró, S
Introduction Adherence to oral anticoagulation (OAC) treatment, vitamin K antagonists or new oral anticoagulants, is an essential element for effectiveness. Information on adherence to OAC in atrial fibrillation (AF) and the impact of adherence on clinical outcomes using real-world data barely exists. We aim to describe the patterns of adherence to OAC over time in patients with AF, estimate the associated factors and their impact on clinical events, and assess the same issues with conventional measures of primary and secondary adherence—proportion of days covered (PDC) and persistence—in routine clinical practice. Methods and analysis This is a population-based retrospective cohort study including all patients with AF treated with OAC from 2010 to date in Valencia, Spain; data will be obtained from diverse electronic records of the Valencia Health Agency. Primary outcome measure: adherence trajectories. Secondary outcomes: (1) primary non-adherence; (2) secondary adherence: (a) PDC, (b) persistence. Clinical outcomes: hospitalisation for haemorrhagic or thromboembolic events and death during follow-up. Analysis: (1) description of baseline characteristics, adherence patterns (trajectory models or latent class growth analysis models) and conventional adherence measures; (2) logistic or Cox multivariate regression models, to assess the associations between adherence measures and the covariates, and logistic multinomial regression models, to identify characteristics associated with each trajectory; (3) Cox proportional hazard models, to assess the relationship between adherence and clinical outcomes, with propensity score adjustment applied to further control for potential confounders; (4) to estimate the importance of different healthcare levels in the variations of adherence, logistic or Cox multilevel regression models. Ethics and dissemination This study has been approved by the corresponding Clinical Research Ethics Committee. We plan to disseminate the
Gómez-Outes, Antonio; Suárez-Gea, Ma Luisa; Calvo-Rojas, Gonzalo; Lecumberri, Ramón; Rocha, Eduardo; Pozo-Hernández, Carmen; Terleira-Fernández, Ana Isabel; Vargas-Castrillón, Emilio
The history of the traditional anticoagulants is marked by both perseverance and serendipity. The anticoagulant effect of heparin was discovered by McLean in 1915, while he was searching for a procoagulant in dog liver. Link identified dicumarol from spoiled sweet clover hay in 1939 as the causal agent of the sweet clover disease, a hemorrhagic disorder in cattle. Hirudin extracts from the medicinal leech were first used for parenteral anticoagulation in the clinic in 1909, but their use was limited due to adverse effects and difficulties in achieving highly purified extracts. Heparins and coumarins (i.e.: warfarin, phenprocoumon, acenocoumarol) have been the mainstay of anticoagulant therapy for more than 60 years. Over the past decades, the drug discovery paradigm has shifted toward rational design following a target-based approach, in which specific proteins, or "targets", are chosen on current understandings of pathophysiology, small molecules that inhibit the target's activity may be identified by high-throughput screening and, in selected cases, these new molecules can be developed further as drugs. Despite the application of rational design, serendipity has still played a significant role in some of the new discoveries. This review will focus on the discovery of the main anticoagulant drugs in current clinical use, like unfractionated heparin, low-molecular-weight heparins, fondaparinux, coumarins (i.e.: warfarin, acenocoumarol, phenprocoumon), parenteral direct thrombin inhibitors (DTIs) (i.e.: argatroban, recombinant hirudins, bivalirudin), oral DTIs (i.e.: dabigatran) and oral direct factor Xa inhibitors (i.e.: rivaroxaban, apixaban).
Mischke, Karl; Knackstedt, Christian; Marx, Nikolaus
Anticoagulation represents the mainstay of therapy for most patients with atrial fibrillation. Patients on oral anticoagulation often require concomitant antiplatelet therapy, mostly because of coronary artery disease. After coronary stent implantation, dual antiplatelet therapy is necessary. However, the combination of oral anticoagulation and antiplatelet therapy increases the bleeding risk. Risk scores such as the CHA2DS2-Vasc score and the HAS-BLED score help to identify both bleeding and stroke risk in individual patients. The guidelines of the European Society of Cardiology provide a rather detailed recommendation for patients on oral anticoagulation after coronary stent implantation. However, robust evidence is lacking for some of the recommendations, and especially for new oral anticoagulants and new antiplatelets few or no data are available. This review addresses some of the critical points of the guidelines and discusses potential advantages of new anticoagulants in patients with atrial fibrillation after stent implantation. PMID:22577538
Bi, Mingda; Kyad, Ali; Alvarez-Nunez, Fernando; Alvarez, Francisco
Enhancing and sustaining AMG 009 dissolution from a matrix tablet via microenvironmental pH modulation and supersaturation, where poorly soluble acidic AMG 009 molecule was intimately mixed and compressed together with a basic pH modifier (e.g., sodium carbonate) and nucleation inhibitor hydroxypropyl methylcellulose K100 LV (HPMC K100 LV), was demonstrated previously. However, not all acidic or basic drugs are compatible with basic or acidic pH modifiers either chemically or physically. The objective of this study is to investigate whether similar dissolution enhancement of AMG 009 can be achieved from a bilayer dosage form, where AMG 009 and sodium carbonate are placed in a separate layer with or without the addition of HPMC K100 LV in each layer. Study results indicate that HPMC K100 LV-containing bilayer dosage forms gained similar dissolution enhancement as matrix dosage forms did. Bilayer dosage forms without HPMC K100 LV benefitted the least from dissolution enhancement.
Oral anticoagulants for primary prevention, treatment and secondary prevention of venous thromboembolic disease, and for prevention of stroke in atrial fibrillation: systematic review, network meta-analysis and cost-effectiveness analysis.
Sterne, Jonathan Ac; Bodalia, Pritesh N; Bryden, Peter A; Davies, Philippa A; López-López, Jose A; Okoli, George N; Thom, Howard Hz; Caldwell, Deborah M; Dias, Sofia; Eaton, Diane; Higgins, Julian Pt; Hollingworth, Will; Salisbury, Chris; Savović, Jelena; Sofat, Reecha; Stephens-Boal, Annya; Welton, Nicky J; Hingorani, Aroon D
BACKGROUND Warfarin is effective for stroke prevention in atrial fibrillation (AF), but anticoagulation is underused in clinical care. The risk of venous thromboembolic disease during hospitalisation can be reduced by low-molecular-weight heparin (LMWH): warfarin is the most frequently prescribed anticoagulant for treatment and secondary prevention of venous thromboembolism (VTE). Warfarin-related bleeding is a major reason for hospitalisation for adverse drug effects. Warfarin is cheap but therapeutic monitoring increases treatment costs. Novel oral anticoagulants (NOACs) have more rapid onset and offset of action than warfarin, and more predictable dosing requirements. OBJECTIVE To determine the best oral anticoagulant/s for prevention of stroke in AF and for primary prevention, treatment and secondary prevention of VTE. DESIGN Four systematic reviews, network meta-analyses (NMAs) and cost-effectiveness analyses (CEAs) of randomised controlled trials. SETTING Hospital (VTE primary prevention and acute treatment) and primary care/anticoagulation clinics (AF and VTE secondary prevention). PARTICIPANTS Patients eligible for anticoagulation with warfarin (stroke prevention in AF, acute treatment or secondary prevention of VTE) or LMWH (primary prevention of VTE). INTERVENTIONS NOACs, warfarin and LMWH, together with other interventions (antiplatelet therapy, placebo) evaluated in the evidence network. MAIN OUTCOME MEASURES Efficacy Stroke, symptomatic VTE, symptomatic deep-vein thrombosis and symptomatic pulmonary embolism. Safety Major bleeding, clinically relevant bleeding and intracranial haemorrhage. We also considered myocardial infarction and all-cause mortality and evaluated cost-effectiveness. DATA SOURCES MEDLINE and PREMEDLINE In-Process & Other Non-Indexed Citations, EMBASE and The Cochrane Library, reference lists of published NMAs and trial registries. We searched MEDLINE and PREMEDLINE In-Process & Other Non-Indexed Citations, EMBASE and The
Chih-Wen Cheng; Hang Wu; Thompson, Pamela J; Taylor, Julie R; Zehnbauer, Barbara A; Wilson, Karlyn K; Wang, May D
Patients with certain clotting disorders or conditions have a greater risk of developing arterial or venous clots and downstream embolisms, strokes, and arterial insufficiency. These patients need prescription anticoagulant drugs to reduce the possibility of clot formation. However, historically, the clinical decision making workflow in determining the correct type and dosage of anticoagulant(s) is part science and part art. To address this problem, we developed Anticoagulation Manager, an intelligent clinical decision workflow management system on iOS-based mobile devices to help clinicians effectively choose the most appropriate and helpful follow-up clotting tests for patients with a common clotting profile. The app can provide physicians guidance to prescribe the most appropriate medication for patients in need of anticoagulant drugs. This intelligent app was jointly designed and developed by medical professionals in CDC and engineers at Georgia Tech, and will be evaluated by physicians for ease-of-use, robustness, flexibility, and scalability. Eventually, it will be deployed and shared in both physician community and developer community.
Schulman, Sam; Witt, Daniel M.; Vandvik, Per Olav; Fish, Jason; Kovacs, Michael J.; Svensson, Peter J.; Veenstra, David L.; Crowther, Mark; Guyatt, Gordon H.
Background: High-quality anticoagulation management is required to keep these narrow therapeutic index medications as effective and safe as possible. This article focuses on the common important management questions for which, at a minimum, low-quality published evidence is available to guide best practices. Methods: The methods of this guideline follow those described in Methodology for the Development of Antithrombotic Therapy and Prevention of Thrombosis Guidelines: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines in this supplement. Results: Most practical clinical questions regarding the management of anticoagulation, both oral and parenteral, have not been adequately addressed by randomized trials. We found sufficient evidence for summaries of recommendations for 23 questions, of which only two are strong rather than weak recommendations. Strong recommendations include targeting an international normalized ratio of 2.0 to 3.0 for patients on vitamin K antagonist therapy (Grade 1B) and not routinely using pharmacogenetic testing for guiding doses of vitamin K antagonist (Grade 1B). Weak recommendations deal with such issues as loading doses, initiation overlap, monitoring frequency, vitamin K supplementation, patient self-management, weight and renal function adjustment of doses, dosing decision support, drug interactions to avoid, and prevention and management of bleeding complications. We also address anticoagulation management services and intensive patient education. Conclusions: We offer guidance for many common anticoagulation-related management problems. Most anticoagulation management questions have not been adequately studied. PMID:22315259
Yasaka, Masahiro; Okada, Yasushi
Novel anticoagulants including dabigatran and rivaroxaban have lower incidence of intracranial hemorrhage compared to warfarin. Therefore, in patients with high risks for intracranial hemorrhage, such as past history of brain infarction, brain hemorrhage, microbleeds on MRI, or concomitant use of antiplatelet, novel anticoagulant may be appropriate. Irrespective of any anticoagulants, it is essential to manage controllable risk factors, such as hypertension, diabetes mellitus, smoking habit, and excessive alcohol drinking. Combination therapy of other antithrombotic agents had better be avoided as long as possible. In emergency of hemorrhage complications, discontinuation of anticoagulants, procedure to stop bleeding, and appropriate intravenous infusion is quite important and lowering blood pressure is also important when intracranial hemorrhage happens. There is no antidote to novel anticoagulants. However, oral activated charcoal may be effective if early after taking medicine. The dabigatran can be dialysed. Some experimental evidences support the role of prothrombin complex concentrate to stop bleeding. However, their usefulness in clinical setting has not been established. Collecting and analyzing data regarding immediate reversal of novel anticoagulants is required in near future.
da Silva Saraiva, Sabrina; Orsi, Fernanda Andrade; Santos, Marcos Pereira; Machado, Tania; Montalvão, Silmara; Costa-Lima, Carolina; de Paula, Erich Vinícius; Colella, Marina Pereira; Annichino-Bizzacchi, Joyce
The home prothrombin time/international normalized ratio (PT/INR) self-management could be convenient for patients, enhancing treatment compliance and improving the quality of the oral anticoagulation. However, patient self-management (PSM) of oral anticoagulation may not be feasible for up to half of the patients due to cognitive or educational issues. In the present study, we aimed to evaluate the feasibility of a PSM program in a public health medical center that provides care for low-income patients. We also aimed to determine the accuracy of individual point-of-care devices (CoaguChek XS(®)) during long-term of home manipulation. Patients' time-in-therapeutic range (TTR) and perception of quality of life, were evaluated at scheduled study-visits to the center. Additionally, the accuracy of individual CoaguChek XS(®) was evaluated in comparison to the standard automated coagulometer at scheduled study-visits to the center. Twenty-five patients were included in the PSM program. The median TTR of patients was 75 % before inclusion, 72 % at 3 months, 75 % at 6 months and 100 % at 12 months after the beginning of self-management (P = 0.14).The median DASS scores were 64, 63, 61.5 and 71.5 before inclusion and at 3, 6 and 12 months, respectively (P = 0.09). One hundred paired INR values were obtained. Correlation between INR values delivered by individual CoaguChek XS(®) and the automated coagulometer was 94 % and the mean result bias was 0.07 INR units. The coefficient of correlation and the mean bias between methods was stable during 24 months of follow-up. The present study suggests that PSM is feasible for patients treated in the public health system and that the results delivered by CoaguChek XS(®) have long-term reliability.
Agarwal, Manoj; Mittal, Sankalp; Vijay, Sharmistha; Yadav, Pooja; Panwar, Vasim Raja; Gupta, Neha
Patients taking anticoagulant medication pose a challenge for the clinician. Dentists are often required to manage bleeding as part of routine oral surgery or dental procedures, and altered hemostasis can lead to complications. Nevertheless, use of these medications is generally important for the patient's health and any alteration in the anticoagulant regimen may have untoward sequelae. In addition, several medications can affect the clotting mechanism, potentially compromising hemostasis. This article will review a variety of anticoagulant medications and the medical conditions that necessitate their use.
Nowak-Göttl, U; Langer, F; Limperger, V; Mesters, R; Trappe, R U
Oral anticoagulants [Vitamin-K-Antagonists, Dabigatran, Rivaroxaban, Apixaban] or antiplatelet agents [Aspirin, Clopidogrel, Prasugrel, Ticagrelor] are effective in preventing thromboembolic diseases. In case of interventional of surgical procedures patients with indications for chronic anticoagulation [atrial fibrillation, valve prosthesis, venous thromboembolism] or use of antiplatelet agents [cerebrovascular events, cardiovascular events] will require interruption of antithrombotic/antiplatelet therapy with the need of replacement with a short-acting agent. Due to limited data available from randomized studies and meta-analyses the evidence level is low in the majority of recommendations. Therefore for each patient the bleeding and thrombosis risk depending on the individual patient constitution and the planned intervention must be weighted. In patients with an intermediate risk for thrombosis the bleeding risk of the scheduled intervention will influence the bridging recommendation: In patients with a low bleeding risk oral anticoagulation/antiplatelet therapy can be continued or reduced in intensity. In patients with an intermediate or high bleeding risk along with a low thrombosis risk a temporary interruption of the anticoagulation/antiplatelet therapy is feasible. In patients with a high thrombosis and bleeding risk anticoagulation should be bridged with unfractionated heparin [renal insufficiency] or low molecular weight heparin. In the latter risk situation, inhibition of platelet function can be achieved with short-lasting GPIIb-IIIa inhibitors [Eptifibatide, Tirofiban]. Prior to intervention patients treated with the new oral anticoagulants [Dabigatran; Rivaroxaban; Apixaban] are requested to temporary interrupt the anticoagulation depending on the individual drug half-life and their renal function. Bridging therapy with heparin prior to intervention is not necessary with the new oral anticoagulants.
Bastida, Carla; Corominas, Núria; Sotoca, José Miguel; Rovira, Marina
Background Few studies assess the use of non-vitamin K antagonist oral anticoagulants (NOACs) in daily practice for the prevention of thromboembolic complications associated to nonvalvular atrial fibrillation (AF). Objectives Describe NOACs' use and analyze its prescribing pattern. Evaluate possible factors associated to adverse events (AEs) and the applicability of prescription support forms. Methods We included patients with AF treated with a NOAC during 2014 in three primary healthcare centers in Barcelona, Spain. Demographic and clinical data was collected, as well as embolic and bleeding risk and reported AEs. Results A total of 101 patients were included, with a median age of 75 years. The NOACs most frequently prescribed were dabigatran and rivaroxaban. An 87.2% of the patients were receiving the recommended dosage. A potential bleeding risk was present in 47% of the subjects. Ten AEs were reported, of which eight hemorrhages. Patients who presented an AE were >65 years and had a higher proportion of concomitant treatment and/or co-morbidities that could prompt to bleeding (p < 0.001). Conclusions Current treatment practice is according to regulatory agencies' recommendations. Close monitoring is especially needed in patients >65 years and at higher risk of bleeding. Prescription support forms help good prescribing and identifying potential individuals at high risk of AEs.
Larsen, Torben Bjerregaard; Nielsen, Peter Brønnum; Skjøth, Flemming; Rasmussen, Lars Hvilsted; Lip, Gregory Y. H.
Background This study sought to investigate the relative efficacy and safety of non-vitamin K oral anticoagulants (NOACs) for the treatment of venous thromboembolism (VTE) in cancer patients. Methods A systematic search of the PubMed, EMBASE, and ClinicalTrials.gov databases identified all multicentre, randomised phase III trials investigating the initial use of NOAC against a vitamin K antagonist (VKA) together with subcutaneous heparin or low molecular weight heparin (upstart) for treatment of VTE. Outcomes of interest were recurrent VTE (deep venous thrombosis or pulmonary embolism), and clinically relevant bleeding. Results Four randomised controlled phase III trials were included, comprising a total of 19,060 patients randomised to either NOAC or VKA. For patients with active cancer (N = 759), the analysis on the efficacy outcomes demonstrated a trend in favour of NOAC (OR 0.56, 95% CI 0.28–1.13). Similar, analyses on the safety outcomes comparing NOAC to VKA and enoxaparin demonstrated a trend in favour of NOAC (OR 0.88, 95% CI 0.57–1.35). Conclusion Point estimates of the effect size suggest an important estimated beneficial effect of NOAC in the treatment of VTE in cancer, in terms of efficacy and safety, but given the small numbers of patients with cancer in the randomised trials, statistical significance was not achieved. PMID:25479007
Babilonia, Katrina; Trujillo, Toby
Over the past several years a new era for patients requiring anticoagulation has arrived. The approval of new target specific oral anticoagulants offers practitioners several advantages over traditionally used vitamin K antagonist agents including predictable pharmacokinetics, rapid onset of action, comparable efficacy and safety, all without the need for routine monitoring. Despite these benefits, hemorrhagic complicates are inevitable with any anticoagulation treatment. One of the major disadvantages of the new oral anticoagulants is lack of specific antidotes or reversal agents for patients with serious bleeding or need for urgent surgery. As use of the new target specific oral anticoagulants continues to increase, practitioners will need to understand both the pharmacodynamics and pharmacokinetic properties of the agents, as well as, the available literature with use of non-specific therapies to reverse anticoagulation. Four factor prothrombin complex concentrates have been available for several years in Europe, and recently became available in the United States with approval of Kcentra. These products have shown efficacy in reversing anticoagulation from vitamin K antagonists, however their usefulness with the new target specific oral anticoagulants is poorly understood. This article will review the properties of dabigatran, rivaroxaban and apixaban, as well as the limited literature available on the effectiveness of prothrombin complex concentrates in reversal of their anticoagulant effects. Additional studies are needed to more accurately define the role of prothrombin complex concentrates in patients with life threatening bleeding or who require emergent surgery, as current data is both limited and conflicting.
Over the past several years a new era for patients requiring anticoagulation has arrived. The approval of new target specific oral anticoagulants offers practitioners several advantages over traditionally used vitamin K antagonist agents including predictable pharmacokinetics, rapid onset of action, comparable efficacy and safety, all without the need for routine monitoring. Despite these benefits, hemorrhagic complicates are inevitable with any anticoagulation treatment. One of the major disadvantages of the new oral anticoagulants is lack of specific antidotes or reversal agents for patients with serious bleeding or need for urgent surgery. As use of the new target specific oral anticoagulants continues to increase, practitioners will need to understand both the pharmacodynamics and pharmacokinetic properties of the agents, as well as, the available literature with use of non-specific therapies to reverse anticoagulation. Four factor prothrombin complex concentrates have been available for several years in Europe, and recently became available in the United States with approval of Kcentra. These products have shown efficacy in reversing anticoagulation from vitamin K antagonists, however their usefulness with the new target specific oral anticoagulants is poorly understood. This article will review the properties of dabigatran, rivaroxaban and apixaban, as well as the limited literature available on the effectiveness of prothrombin complex concentrates in reversal of their anticoagulant effects. Additional studies are needed to more accurately define the role of prothrombin complex concentrates in patients with life threatening bleeding or who require emergent surgery, as current data is both limited and conflicting. PMID:24742134
Cox, P J; Khan, K A; Munday, D L; Sujja-areevath, J
Mini-matrix tablets containing S(+)-ibuprofen have been prepared by the wet granulation method. The hydrophilic matrix was formed with either xanthan gum, karaya gum or hydroxymethylcellulose (HPMC) together with a choice of additives from lactose, Encompress(R), Avicel(R) PH101, talc and Lubritab(R). Multiple unit dosage forms (MUDFs) were subsequently obtained by encapsulating the mini-matrix tablets into hard gelatin capsules. Preparation, in vitro release profiles and release kinetics are presented.
Dang, Yi-Ping; Chen, Yun-Fei; Li, Yi-Qing; Zhao, Lei
Deep Vein Thrombosis (DVT) has been known as a common medical problem all over the world. Thrombus traveling in blood vessels may lead to pulmonary embolism (PE), associated with high rates of mortality. Anticoagulant therapy is the mainstay treatment of DVT. Common anticoagulants, Vitamin K antagonists (VKAs), unfractionated heparin (UFH) and Low-molecular-weight heparin (LMWH) have been used in clinical application over decades, but can increase the risk of hemorrhage. Thereby, several new oral anticoagulants (NOACs) have been developed, which includes direct thrombin inhibitors (DTI) and direct factor Xa inhibitors. To be contrast with VKAs and UFH, NOACs have many advantages such as rapid offset action, few drug/food interactions and no need for routine coagulation monitoring, etc. Many NOACs are still being evaluated in Phase III clinical trials such as Betrixaban and Darexaban (YM150). However, NOACs still have problems to be solved such as lack of antidotes and laboratory monitoring, high drug costs, etc. Besides, several agents have already shown the potential to be new anticoagulants. Factor Xa play an important role in thrombin generation and coagulation pathway. Thus, the new compounds directly targeting on factor Xa for prevention DVT are highly anticipated. DPC423, a new series of 6-substituted coumarin derivatives and Phenyltriazolinones as potent factor Xa inhibitors have been recently reported. Recent studies revealed that agents extracted from botanicals not only have anti-coagulant effects but also possess other pharmacological activities such as anti-inflammation to alleviate the post-thrombotic syndromes. All the evidence above suggests that many new compounds might have great potential to be more effective and safe oral anticoagulants.
Davis, Estella M; Packard, Kathleen A; Knezevich, Jon T; Campbell, Jennifer A
Abstract Thrombosis is an underlying cause of many cardiovascular disorders, and generation of thrombi in the arterial circulation can lead to unstable angina, myocardial infarction, or ischemic stroke. Antithrombotic therapy is widely used, with proven benefit to prevent ischemic stroke and thromboembolic events in patients with atrial fibrillation (AF) or to prevent further ischemic complications in patients with acute coronary syndrome (ACS). Traditional anticoagulants (including unfractionated heparin, low-molecular-weight heparin, and warfarin) and antiplatelet agents (including aspirin, clopidogrel, and prasugrel) are typically used for these indications. Limitations to their use include variable pharmacokinetic and pharmacodynamic profiles, inability to inhibit fibrin-bound thrombin, risk of heparin-induced thrombocytopenia, delayed onset of action, numerous drug interactions, need for substantial laboratory monitoring and dosage titrations, hyporesponsiveness or resistance, hypersensitivity, adverse events, and bleeding. To overcome some of the limitations of traditional agents, new antithrombotic agents under development are highly selective for specific coagulation factors blocking the synthesis of thrombin. Clinicians must have an understanding of the new anticoagulants to aid in the selection of appropriate therapies for patients. We describe the most relevant phases II and III clinical trials that evaluated several recent emerging anticoagulant drugs for use in patients with AF or ACS. The advantages of many new agents include predictable pharmaco-dynamic response and pharmacokinetic parameters, allowing for fixed oral dosing with no need for laboratory monitoring. For patients with AF, dabigatran is already approved for the prevention of stroke and systemic embolism, rivaroxaban appears to be an effective alternative to warfarin in high-risk patients, and apixaban may also be an effective alternative to aspirin in patients unable to take warfarin
Feagins, Linda Anne
Colonoscopy frequently is performed for patients who are taking aspirin, NSAIDs, antiplatelet agents and other anticoagulants. These colonoscopies often involve polypectomy, which can be complicated by bleeding. The risks of precipitating thromboembolic complications if anticoagulants are stopped must be weighed against the risk of postpolypectomy bleeding if these agents are continued. This article systematically reviews the management of anticoagulation during elective and emergency colonoscopy. For patients undergoing colonoscopic polypectomy, the overall of risk of postpolypectomy bleeding is less than 0.5%. Risk factors for postpolypectomy bleeding include large polyp size and anticoagulant use, especially warfarin and thienopyridines. For patients who do not stop aspirin or other NSAIDs prior to colonoscopy, the rate of postpolypectomy bleeding is not significantly different than that for patients who do not take those medications. For patients who continue thienopyridines and undergo polypectomy, the risk of delayed postpolypectomy bleeding is approximately 2.4%. Even for patients who interrupt warfarin, the risk of postpolypectomy bleeding is increased. The direct oral anticoagulants (direct thrombin inhibitors and factor Xa inhibitors) have a rapid onset and offset of action, and periprocedural bridging generally is not necessary. For the thienopyridines, warfarin and the direct oral anticoagulants, the decision to interrupt or continue these agents for endoscopy will involve considerable exercise of clinical judgment.
Radaelli, Franco; Dentali, Francesco; Repici, Alessandro; Amato, Arnaldo; Paggi, Silvia; Rondonotti, Emanuele; Dumonceau, Jean Marc
Acute gastrointestinal bleeding represents the most common adverse event associated with the use of oral anticoagulant therapy. Due to increasing prescription of anticoagulants worldwide, gastroenterologists are more and more called to deal with bleeding patients taking these medications. Their management is challenging because several issues have to be taken into account, such as the severity of bleeding, the intensity of anticoagulation, the patient's thrombotic risk and endoscopy findings. The recent introduction into the marketplace of new direct oral anticoagulants, for whom specific reversal agents are still lacking, further contributes to make the decision-making process even more demanding. Available evidence on this topic is limited and practice guidelines by gastroenterology societies only marginally address key issues for clinicians, including when and how to reverse coagulopathy, the optimal timing of endoscopy and when and how to resume anticoagulation thereafter. The present paper reviews the evidence in the literature and provides practical algorithms to support clinicians in the management of patients on anticoagulants who present with acute gastrointestinal bleeding.
Pinède, Laurent; Ninet, Jacques
The curative anticoagulant treatment of venous thromboembolism is non fractionated heparin or low molecular weight heparin, secondly substituted by oral anticoagulant therapy. Early mobilisation and elastic contention should be systematically prescribed. Low molecular weight heparin once or twice a day and early substitution by vitamin K antagonist allow an ambulatory treatment for deep vein thrombosis. It is still recommended a hospital management for patients with symptomatic pulmonary embolism. It is necessary to tailor the duration of anticoagulation individually according to the extension of venous thromboembolism and the presence (or absence) of risk or triggering factors. Bleeding is the major risk of anticoagulant therapy, particularly the vitamin K antagonists, justifying patient's education, adapted and regular biological surveillance, co-ordinated care approach with practical recommendations, patient's self-monitoring.
Mizoe, Takuto; Ozeki, Tetsuya; Okada, Hiroaki
We prepared microparticles containing nanoparticles of water-insoluble pranlukast hemihydrate (PLH) using a 4-fluid nozzle spray drier. These particles were designed to improve the absorption of PLH and to allow delivery by oral, pulmonary, and injection routes. Mannitol (MAN) was used as a water-soluble carrier for the microparticles. We orally administered suspensions of PLH powder and PLH-MAN microparticles to rats. We also compared the in vitro aerosol performance of the PLH powder and PLH-MAN microparticles using a cascade impactor, and we compared the delivery of PLH by oral administration of PLH powder and pulmonary delivery of PLH-MAN microparticles at PLH/MAN ratios of 1:4 and 1:10. The absorption of PLH was markedly enhanced by pulmonary deliver of PLH-MAN composite microparticles. The area under the plasma concentration-time curve per dose for pulmonary administration of the 1:4 and 1:10 PLH-MAN microparticles was approximately 85- and 100-fold higher, respectively, than for oral administration of PLH powder. Also, we found that PLH rapidly disappeared from the plasma following injection of PLH aqueous solution or PLH-MAN microparticles dissolved in water. The PLH particles remaining after dissolution of MAN from the 1:10 PLH-MAN microparticles were 200 nm in diameter. Therefore, PLH particles may be captured immediately after injection by reticuloendothelial tissues such as the liver and spleen. This study demonstrated that it is possible to use the 4-fluid spray drier to prepare microparticles containing PLH nanoparticles that that improve drug absorption and can be administered by oral, pulmonary, and injection routes.
Monreal-Bosch, M; Soulard, S; Crespo, C; Brand, S; Kansal, A
Introduccion. El apixaban, el dabigatran y el rivaroxaban son tres anticoagulantes orales de accion directa (ACOD) indicados para la prevencion del ictus y la embolia sistemica en pacientes con fibrilacion auricular no valvular (FANV) en España. Objetivo. Comparar el coste-utilidad de los tres ACOD frente a los antivitamina K. Pacientes y metodos. Se utilizo un modelo Markov con ciclos trimestrales para simular pacientes con FANV desde que inician su tratamiento hasta el resto de su vida desde la perspectiva del Sistema Nacional de Salud. El modelo incorporo 36 estados de salud, incluyendo combinaciones de tratamientos, discapacidad y antecedentes de eventos, y considero una cohorte hipotetica de 10.000 pacientes con FANV. La eficacia relativa se calculo a partir de una comparacion indirecta formal de los tratamientos segun los datos de los ensayos pivotales de cada ACOD. Resultados. El dabigatran se asocio al valor maximo de años de vida ajustados por calidad (AVAC) (8,40 AVAC), seguido del apixaban (8,33 AVAC), el rivaroxaban (8,15 AVAC) y el acenocumarol (8,03 AVAC). Los costes totales fueron menores con el acenocumarol (22.230 €), seguido del dabigatran (24.564 €), el apixaban (24.655 €) y el rivaroxaban (25.900 €). La ratio coste-utilidad incremental frente a los antivitamina K fue de 6.397, 8.039 y 29.957 €/AVAC para el dabigatran, el apixaban y el rivaroxaban, respectivamente. Comparados entre ellos, el dabigatran domino al apixaban y al rivaroxaban. Los analisis de sensibilidad confirmaron la robustez del caso base. Conclusiones. Los tres ACOD son coste-efectivos frente al acenocumarol. El dabigatran es economicamente dominante frente al rivaroxaban y al apixaban en España, al ser mas efectivo y menos costoso.
Meléndez, Peter A; Kane, Kevin M; Ashvar, Claudine S; Albrecht, Mary; Smith, Pamela A
The utility of thermal inkjet (TIJ) technology for preparing solid dosage forms of drugs was examined. Solutions of prednisolone in a solvent mixture of ethanol, water, and glycerol (80/17/3 by volume) were dispensed onto poly(tetrafluoroethylene)-coated fiberglass films using TIJ cartridges and a personal printer and using a micropipette for comparison. The post-dried, TIJ-dispensed samples were shown to contain a mixture of prednisolone Forms I and III based on PXRD analyses that were confirmed by Raman analyses. The starting commercial material was determined to be Form I. Samples prepared by dispensing the solution from a micropipette initially showed only Form I; subsequent Raman mapping of these samples revealed the presence of two polymorphs. Raman mapping of the TIJ-dispensed samples also showed both polymorphs. The results indicate that the solvent mixture used in the dispensing solution combined with the thermal treatment of the samples after dispensing were likely the primary reason for the generation of the two polymorphs. The advantages of using a multidisciplinary approach to characterize drug delivery systems are demonstrated using solid state mapping techniques. Both PXRD and Raman spectroscopy were needed to fully characterize the samples. Finally, this report clarifies prednisolone's polymorphic nomenclature existent in the scientific literature.
Trivedi, Rakshit Kanubhai; Patel, Mukesh C.
A simple, sensitive and reproducible reversed phase ultra performance liquid chromatography (RP-UPLC) coupled with a photodiode array detector method was developed for the quantitative determination of metaxalone (META) in pharmaceutical dosage forms. The method is applicable to the quantification of related substances and assay of drug product. Chromatographic separation was achieved on an Acquity® HSS-T3 (100 mm x 2.1 mm, 1.7 μm) column. The optimized isocratic mobile phase consists of a mixture of water, methanol, acetonitrile and triethylamine in the ratio of 50:25:25:0.1 % v/v (pH adjusted to 6.3 with orthophosphoric acid). The eluted compounds were monitored at 230 nm for META assay and 205 nm for related substances, the flow rate was 0.3 mL/min, and the column oven temperature was maintained at 45°C. The developed method separated META from its two known and two unknown impurities within 6.0 min. Metaxalone was subjected to the stress conditions of oxidative, acid, base, hydrolytic, thermal and photolytic degradation. Metaxalone was found to degrade significantly in base stress condition, degrade slightly in oxidative stress condition and remain stable in acid, hydrolytic, thermal and photolytic degradation conditions. All impurities were well resolved from each other and from the main peak, showing the stability-indicating power of the method. The developed method was validated as per International Conference on Harmonization (ICH) guidelines. PMID:22896822
Weitz, Jeffrey I.; Fredenburgh, James C.
Compared with vitamin K antagonists, the direct oral anticoagulants (DOACs) are simpler to administer and are associated with less intracranial bleeding. Nonetheless, even with the DOACs, bleeding still occurs and many patients with atrial fibrillation fail to receive anticoagulant thromboprophylaxis because of the fear of bleeding. Therefore, there is an urgent need for safer anticoagulants. Recent investigations into the biochemistry of hemostasis and thrombosis have identified new targets for development of novel anticoagulants. Using data from complementary sources, including epidemiological studies and investigations in various animal models, the contact pathway has emerged as a potential mediator of thrombosis that plays a minor part in hemostasis. Consequently, factor (F) XII of the contact system and FXI in the intrinsic pathway have been identified as potentially safer targets of anticoagulation than thrombin or FXa. However, further studies are needed to identify which is the better target for the appropriate indication. This review highlights the evidence for focusing on FXI and FXII and examines the novel approaches directed at these new targets. These emerging strategies should address current unmet medical needs and provide new avenues by which to improve anticoagulant therapy by reducing the risk of bleeding. PMID:28286749
A Pilot Study Evaluating Therapeutic Response of Different Dosage of Oral Glucocorticoid in Two Children with Familial Glucocorticoid Deficiency Presenting with Diffuse Mucocutaneous Hyperpigmentation
Sarkar, Uttam Kumar; Sarma, Nilendu; Debbarma, Sambreeta; Mandal, Asok Kumar; Bala, Ashok Kumar
Introduction: Familial glucocorticoid deficiency (FGD) is a rare autosomal recessive potentially life-threatening condition, characterized by glucocorticoid deficiency, preserved aldosterone/renin secretion, and secondary rise in plasma adrenocorticotropic hormone level. This occurs due to either mutation in adrenocorticotropic receptor (25%, FGD Type-1) or in the MC2 receptor accessory protein (15%–20%). However, in about 50% patients, no identifiable mutations have been identified. Clinically, it manifests with weakness, fatigue, weight loss, anorexia, nausea, vomiting, diarrhea, abdominal pain, hypoglycemia, and hypothermia. Progressive mucocutaneous pigmentation is a conspicuous presentation. Repeated hypoglycemia may result in seizure, persistent neurological, severe mental disability, and even sudden death. Standard therapy is oral glucocorticoids (10–15 mg/m2). Patients and Results: Two familial cases of FGD were put on progressively increasing doses of oral glucocorticoids (10 mg, 15 mg, and 20 mg/m2/day, each for 6 weeks) to achieve the best response without any adverse effects. One patient had excellent improvement with 15 mg/m2/day, and another required 20 mg/m2/day. The latter patient had excellent overall improvement with only moderate improvement in pigmentation. Conclusion: Glucocorticoids replacement with optimum dose is necessary in FGD to promote physical and neurological growth and to prevent adrenal crises, hypotension, hypoglycemia, and sudden death. Higher dose than mentioned in literature (15 mg/m2/day) may be required in selected cases. Mucocutaneous pigmentation may require even higher dose than we used. More studies are required.
Santos, M R; Rodríguez-Gómez, M J; Justino, G C; Charro, N; Florencio, M H; Mira, L
Background and purpose Flavonoids are known to possess a broad set of pharmacological effects, some of which have been attributed to their antioxidant properties and, more recently, to cell signalling modulation. Nevertheless, flavonoids are extensively metabolized and their metabolites are the potential bioactive forms in vivo. Therefore, a first and crucial step to understand the mechanisms underlying potential health benefits of flavonoids is knowledge of their metabolites and their biological activities. Experimental approach To approximate a human dietary pattern of intake of flavonoids, regular rat chow was supplemented with 0.02% quercetin and fed to Sprague–Dawley rats over 3 weeks. Plasma samples were analysed by HPLC and electrospray tandem mass spectrometry, and plasma antioxidant capacity was measured by the 2,2′-azino-bis(3-ethylbenzothiazoline sulphonate) assay. Key results Major metabolites were 3′-methylquercetin (isorhamnetin) glucuronide sulphate conjugates, the most plausible conjugation positions being at the 3-, 5- and 7-hydroxyl positions. Isorhamnetin conjugates are methylated at the 3′-OH position, which decreases the high antioxidant activity of quercetin and its metabolites and their contribution to plasma antioxidant potential. Conclusions and implications This metabolic pattern differs from that observed after a single high-dose administration, where the major metabolites were quercetin conjugates at 5- and 7-hydroxyl positions and a significantly increased plasma antioxidant activity was observed. These data show altogether that the different metabolic patterns obtained under a prolonged low-dosage regimen or after a single high dose, crucially affected the antioxidant potential of plasma in treated animals. Our data also allow for the establishment of structure–antioxidant activity relationships for quercetin metabolites. PMID:18311191
This study evaluated 44 separate medication withdrawal periods in 17 subjects who were attending a hospital anticoagulation clinic for management of anticoagulation medication. The data suggest that when anticoagulant withdrawal is needed for particular dental procedures, a 2-day hold is an effective period of medication withdrawal. No thromboembolic events were observed after any of the withdrawal periods. Further, no posttreatment hemorrhagic episodes were observed when the anticoagulant medication was reinstituted after dental treatment. Prothrombin time blood levels should be determined in the immediate pretreatment period, however, because the prothrombin time can fluctuate even in the best maintained patients.
Tajiri, Tomokazu; Morita, Shigeaki; Sakamoto, Ryosaku; Mimura, Hisahi; Ozaki, Yukihiro; Reppas, Christos; Kitamura, Satoshi
The objective of this study was to develop an in vitro dissolution test method with discrimination ability for an extended-release solid dispersion matrix of a lipophilic drug using the United States Pharmacopeia (USP) Apparatus 4, flow-through cell apparatus. In the open-loop configuration, the sink condition was maintained by manipulating the flow rate of the dissolution medium. To evaluate the testing conditions, the drug release mechanism from an extended-release solid dispersion matrix containing hydrophobic and hydrophilic polymers was investigated. As the hydroxypropyl methylcellulose (HPMC) maintained concentrations of indomethacin higher than the solubility in a dissolution medium, the release of HPMC into the dissolution medium was also quantified using size-exclusion chromatography. We concluded that the USP Apparatus 4 is suitable for application to an in vitro dissolution method for orally administered extended-release solid dispersion matrix formulations containing poorly water-soluble drugs.
In vitro dissolution of generic immediate-release solid oral dosage forms containing BCS class I drugs: comparative assessment of metronidazole, zidovudine, and amoxicillin versus relevant comparator pharmaceutical products in South Africa and India.
Reddy, Nallagundla H S; Patnala, Srinivas; Löbenberg, Raimar; Kanfer, Isadore
Biowaivers are recommended for immediate-release solid oral dosage forms using dissolution testing as a surrogate for in vivo bioequivalence studies. Several guidance are currently available (the World Health Organization (WHO), the US FDA, and the EMEA) where the conditions are described. In this study, definitions, criteria, and methodologies according to the WHO have been applied. The dissolution performances of immediate-release metronidazole, zidovudine, and amoxicillin products purchased in South African and Indian markets were compared to the relevant comparator pharmaceutical product (CPP)/reference product. The dissolution performances were studied using US Pharmacopeia (USP) apparatus 2 (paddle) set at 75 rpm in each of three dissolution media (pH1.2, 4.5, and 6.8). Concentrations of metronidazole, zidovudine, and amoxicillin in each dissolution media were determined by HPLC. Of the 11 metronidazole products tested, only 8 could be considered as very rapidly dissolving products as defined by the WHO, whereas 2 of those products could be considered as rapidly dissolving products but did not comply with the f 2 acceptance criteria in pH 6.8. All 11 zidovudine products were very rapidly dissolving, whereas in the case of the 14 amoxicillin products tested, none of those products met any of the WHO criteria. This study indicates that not all generic products containing the same biopharmaceutics classification system (BCS) I drug and in similar strength and dosage form are necessarily in vitro equivalent. Hence, there is a need for ongoing market surveillance to determine whether marketed generic products containing BCS I drugs meet the release requirements to confirm their in vitro bioequivalence to the respective reference product.
Akin, Ibrahim; Nienaber, Christoph A
Non-valvular atrial fibrillation is associated with a significantly increased risk of embolic stroke due to blood clot forming predominantly in the left atrial appendage (LAA). Preventive measures to avoid embolic events are permanent administration of anticoagulants or surgical closure of the LAA. Various clinical trials provide evidence about safety, effectiveness and therapeutic success of LAA occlusion using various cardiac occluder devices. The use of such implants for interventional closure of the LAA is likely to become a valuable alternative for stroke prevention, especially in patients with contraindication for oral anticoagulation as safety, clinical benefit and cost-effectiveness of LAA occlusion has recently been demonstrated. PMID:28289527
Dannemiller, Robert; Ward, Tucker; Fanikos, John
Thromboembolism afflicts millions of patients annually in the United States and is associated with a significant cost burden. Oral anticoagulants provide clinicians with options for management of these diseases and their use continues to grow. Accordingly, regulatory, legislative, and nonprofit organizations have set performance standards with the goal of improving patient outcomes, ensuring patient safety, and reducing costs. Recent efforts in quality improvement have introduced changes surrounding regulatory requirements, surveillance, litigation, and oversight that clinicians should be familiar with. This article summarizes key updates related to the management of anticoagulant therapy as it relates to thrombosis prevention and treatment.
Kahsay, Getu; Van Schepdael, Ann; Adams, Erwin
A reversed phase liquid chromatographic method with UV detection for the simultaneous determination of clopidogrel and acetylsalicylic acid and their related substances in combined oral formulations was developed and validated. Good separation was achieved on a Luna C18 column (150 mm × 4.6 mm, 3 μm) using gradient elution at a flow rate of 1 mL/min and a column temperature of 35 °C. UV detection was performed at 220 nm. The validation was performed according to the ICH guidelines. The method proved to be specific, sensitive (LOQ=0.975 μg/mL and 0.0384 μg/mL for clopidogrel and acetylsalicylic acid, respectively), linear in the concentration range from LOQ to 325 μg/mL for clopidogrel and from LOQ to 650 μg/mL for acetylsalicylic acid, precise (RSD values for intermediate precision <1%) and accurate with mean recovery values of 100.7% and 100.2% for clopidogrel and acetylsalicylic acid, respectively. Moreover, the solution stability and method robustness were examined. The method gives satisfactory separation of impurities of clopidogrel and acetylsalicylic acid and so it is suitable for quantification of the related substances as well as for the assay of the actives.
Isola, G; Matarese, G; Cordasco, G; Rotondo, F; Crupi, A; Ramaglia, L
Patients treated with oral anticoagulant therapy (OAT) represent an issue to the dentist, as an increasing number of people are using anticoagulant drugs for cardiovascular disease. The choice of an eventual suspension or continuation of anticoagulant therapy is important when considering an efficient management of the patient. Patients in anticoagulant therapy and requiring dental procedures sometimes represent therapeutic concerns especially concerning the suspension of the anticoagulant treatment. At the moment there is no consensus among international experts of a possible discontinuation of therapy before invasive dental procedures. In this paper, the authors try to focus on this topic through a critical review of the literature. Most of the studies suggest the continuation of the anticoagulant treatment with heparin before invasive oral surgical interventions. Based on the data of the literature, two rules must be adopted in clinical practice: 1) maintenance of anticoagulation related to the international normalized ratio (INR); 2) local application of antifibrinolytic agents to ensure a proper hemostatic process. Given the widespread use of anticoagulant drugs in cardiovascular disease, dentists must often face the problem of the therapy and, since there is no consensus on the management of these patients, the authors propose, after a thorough critical review of the literature, the implementation of a multiphase protocol of surgical approach to be implemented with safety in daily clinical practice.
Wulff, R; Rappen, G-M; Koziolek, M; Garbacz, G; Leopold, C S
The objective of this study was to investigate the suitability of "Eudragit® RL/Eudragit® L55" (RL/L55) blend coatings for a pH-independent release of acidic drugs. A coating for ketoprofen and naproxen mini tablets was developed showing constant drug release rate under pharmacopeial two-stage test conditions for at least 300 min. To simulate drug release from the mini tablets coated with RL/L55 blends in the gastrointestinal (GI) tract, drug release profiles in Hanks buffer pH 6.8 were recorded and compared with drug release profiles in compendial media. RL/L55 blend coatings showed increased drug permeability in Hanks buffer pH 6.8 compared to phosphate buffer pH 6.8 due to its higher ion concentration. However, drug release rates of acidic drugs were lower in Hanks buffer pH 6.8 because of the lower buffer capacity resulting in reduced drug solubility. Further dissolution tests were performed in Hanks buffer using pH sequences simulating the physiological pH conditions in the GI tract. Drug release from mini tablets coated with an RL/L55 blend (8:1) was insensitive to pH changes of the medium within the pH range of 5.8-7.5. It was concluded that coatings of RL/L55 blends show a high potential for application in coated oral drug delivery systems with a special focus on pH-independent release of acidic drugs.
The calculation of dosages in paediatrics is the concern of the whole medical and paramedical team. This activity must generate a minimum of risks in order to prevent care-related adverse events. In this context, the calculation of dosages is a practice which must be understood by everyone.
So, Charlotte H; Eckman, Mark H
The combined use of aspirin and oral anticoagulant therapy in patients with atrial fibrillation (AF) and stable coronary artery disease (CAD) has been questioned due to an increased risk of major bleeding with little to no benefit in preventing ischemic events. (1) To better understand patterns and indications for combined antiplatelet and anticoagulant therapy and identify patients who might reasonably be treated with oral anticoagulant (OAC) therapy alone. (2) To perform an updated literature review regarding the use of combined antiplatelet and OAC therapy in patients with AF and stable CAD. Retrospective review. Patients within the University of Cincinnati Health System with a diagnosis of non-valvular AF, excluding those with acute coronary syndrome or revascularization within the last 12 months. Numbers and indications for combined antiplatelet and anticoagulant therapy and sequence of events leading to the initiation of each. Of 948 patients receiving OAC, 430 (45 %) were receiving concomitant OAC and aspirin. Among patients receiving combined antiplatelet and anticoagulant therapy, 49 and 42 % of patients respectively, had CAD or DM. In a more detailed analysis including chart review of 219 patients receiving combined OAC and aspirin, 27 % had a diagnosis of CAD and 14 % had a diagnosis of DM prior to the development of AF. These patients were initially treated with aspirin. Warfarin was added when they subsequently developed AF but aspirin wasn't discontinued. A surprisingly large proportion of patients (22.8 %) had no obvious indication for dual therapy. Prior myocardial infarction, CAD, vascular disease and DM (among others) increase the likelihood of receiving combined antiplatelet and anticoagulant therapy among patients with AF. A literature review suggests this may lead to increased major bleeding with little benefit in decreasing either AF-related stroke or cardiovascular events.
Wooten, James M
For years, the pharmaceutical industry has been trying to find a safe and effective drug to replace warfarin. Although warfarin is an effective anticoagulant, its pharmacology, adverse effects, and risk profiles dictate that patients taking this medication must be monitored judiciously. The US Food and Drug Administration has approved two drugs for commercial use, dabigatran and rivaroxaban, that will compete directly with warfarin for use in specific indications. Because of direct marketing to patients, physicians are being asked to comment on these new medications. This brief review illustrates the data available for the two new drugs when compared to warfarin for the specified indications. For some patients, these drugs may be highly beneficial and offer an excellent alternative to warfarin. For others, warfarin may still be the preferred drug.
Chen, Feng; Liu, Liping; Bai, Zengguo; Zhang, Tianhua; Zhao, Keke
Here, 3 fluorinated intermediates of drug were synthesized: (M1), (M2), (M3). Three new anticoagulant rodenticides were designed which were based on 4-hydroxycoumarin or 1,3-indandione, added acute toxicity groups containing fluorine. The structures of synthesized compounds were analyzed and proved by FT-IR spectroscopy and (1)H nuclear magnetic resonance ((1)H-NMR). The compounds were also evaluated for their anticoagulant and acute biologic activity. In addition, both the acute orally toxicity and the feeding indexes of R1 and R2 were tested. The result of the experiment proved that the new synthesis of 1, 3 - indan diketone for maternal new anticoagulant rodenticide can replace the current 4 - hydroxyl coumarin as the mother of the second generation anticoagulant rodenticide and 1, 3 - indan diketone for maternal new anticoagulant rodenticides will have a good development prospect.
Cundiff, David K
Context On the basis of theoretical rationale, heparoids and vitamin K antagonists are prescribed to prevent complications of venous thromboembolism (VTE, including pulmonary emboli [PE] and deep vein thrombosis [DVT]). They have been employed as the standard of care for treatment of VTE for over 40 years. Objective Critique the evidence supporting the efficacy of anticoagulants for the treatment of VTE in reducing morbidity and/or mortality. Data Sources This includes a search of reference lists and Medline. Study Selection This includes studies concerning the diagnosis and incidence of PE and DVT, efficacy of anticoagulants in preventing complications, risks of anticoagulant therapy, and the costs of diagnosis and the treatment of VTE. Data Extraction I analyzed references cited in reviews and meta-analyses of VTE, and from Medline searches concerning diagnosis and treatment. The data quality and validity of studies depended on the consistency of findings and statistical significance of the data. Data Synthesis No placebo-controlled trials of anticoagulants as treatment of PE with objective criteria for diagnosis have been published. Three randomized trials of anticoagulants vs no anticoagulants in DVT showed no benefit with heparin and vitamin K antagonists (combined all-cause mortality: anticoagulants = 6/66, un-anticoagulated controls = 1/60, P = .07). No placebo-controlled trials of low-molecular-weight heparins or thrombolytic drugs have been done; therefore, their efficacy in VTE depends entirely on randomized comparisons with unfractionated heparin. They have not been proven safer or more efficacious than unfractionated heparin. Thrombolysis causes more major and fatal bleeds than heparin and is no more effective in preventing PE. Diagnosing and treating VTE patients in the United States with anticoagulants costs $3.2 to $15.5 billion per year (1992 dollars). Bleeding and complications of angiography cause 1017-3525 deaths annually. Conclusion
Diener, H C; Hajjar, K; Frank, B; Perrey, M
Oral anticoagulation with vitamin K antagonists (warfarin, phenprocoumon) is successful in both primary and secondary stroke prevention for patients with atrial fibrillation (AF), yielding a 60-70% relative reduction in stroke risk compared with placebo and a mortality reduction of 26%. However, these agents have a number of well documented shortcomings. This review describes the current landscape and developments in stroke prevention in patients with AF with special reference to secondary prevention. A number of new drugs for oral anticoagulation that do not exhibit the limitations of vitamin K antagonists are under investigation. These include direct factor Xa inhibitors and direct thrombin inhibitors. Recent studies (RE-LY, ROCKET-AF, AVERROES, ARISTOTLE) provide promising results for these new agents including higher efficacy and significantly lower incidences of intracranial bleeding compared with warfarin. The new substances show similar results in secondary as well as in primary stroke prevention in patients with AF. The new anticoagulants add to the therapeutic options for patients with AF and offer a number of advantages over warfarin for both clinician and patient, including a favorable bleeding profile and convenience of use. Consideration of these new anticoagulants will improve clinical decision-making.
Pototski, Mariele; Amenábar, José M
Antiplatelet and anticoagulant agents have been extensively researched and developed as potential therapies in the prevention and management of arterial and venous thrombosis. On the other hand, antiplatelet and anticoagulant drugs have also been associated with an increase in the bleeding time and risk of postoperative hemorrhage. Because of this, some dentists still recommend the patient to stop the therapy for at least 3 days before any oral surgical procedure. However, stopping the use of these drugs exposes the patient to vascular problems, with the potential for significant morbidity. This article reviews the main antiplatelet and anticoagulant drugs in use today and explains the dental management of patients on these drugs, when subjected to minor oral surgery procedures. It can be concluded that the optimal INR value for dental surgical procedures is 2.5 because it minimizes the risk of either hemorrhage or thromboembolism. Nevertheless, minor oral surgical procedures, such as biopsies, tooth extraction and periodontal surgery, can safely be done with an INR lower than 4.0.
Rohan, L C; Devlin, B; Yang, H
Microbicides are topically applied, user controlled dosage forms that are being developed to prevent the transmission of HIV during coitus. Early candidates focused on coitally dependent dosage forms such as gels and creams. More recent development has focused on broadening the coitally dependent options through the introduction of films and fast dissolving tablets. Additionally, it has become important to have longer acting products to minimize the burden of user compliance and thus vaginal rings have been developed providing sustained delivery of antiretroviral drugs. This chapter discusses the history of microbicides along with a detailed description of coitally dependent products, gels, films, tablets diaphragms, as well as coitally independent dosage forms such as vaginal rings and the introduction of a new technology, electrospun fibers.
This review attempts to answer the common questions faced by a clinician regarding thromboembolism and thromboprophylaxis in patients following Fontan surgery. The review is in an easy to understand question and answer format and discusses the currently available literature on the subject in an attempt to arrive at practical clinically relevant solutions. Patients who have undergone the Fontan operation are at a high risk for thromboembolism. Based on available evidence, there is a strong rationale for thromboprophylaxis. However, it is not clear as to which agent should be administered to prevent thromboembolic events. While the available evidence suggests that antiplatelet agents alone may be as good as oral anticoagulants, there is a need for a large multicenter randomized control trial comparing these two common strategies to deliver a clear verdict. PMID:27625521
Non-vitamin K antagonist (VKA) oral anticoagulants (NOACs) have emerged as alternatives to VKAs for the prevention of stroke in patients with non-valvular atrial fibrillation. Four NOACS: dabigatran, apixaban, rivaroxaban and edoxaban, have received regulatory approval in Europe from the European Medicines Agency. Numerous factors can influence the decision to prescribe a NOAC, the most important of which are assessment of stroke and bleeding risks. Given the variation in design of the pivotal phase III clinical trials investigating the efficacy and safety of NOACs, and in the absence of head-to-head comparative data, it is impossible to recommend one NOAC over the other. However, NOACS offer the opportunity for individualised therapy based on factors such as renal function, age or patient/doctor preference for once- or twice-daily dosing regimens. Dose reduction of some NOACS should be considered in at-risk patient populations. PMID:27617088