Propensity score methods for comparative-effectiveness analysis: A case study of direct oral anticoagulants in the atrial fibrillation population.

OBJECTIVE: To explore methodological challenges when using real-world evidence (RWE) to estimate comparative-effectiveness in the context of Health Technology Assessment of direct oral anticoagulants (DOACs) in Scotland. METHODS: We used linkage data from the Prescribing Information System (PIS), Scottish Morbidity Records (SMR) and mortality records for newly anticoagulated patients to explore methodological challenges in the use of Propensity score (PS) matching, Inverse Probability Weighting (IPW) and covariate adjustment with PS. Model performance was assessed by standardised difference. Clinical outcomes (stroke and major bleeding) and mortality were compared for all DOACs (including apixaban, dabigatran and rivaroxaban) versus warfarin. Patients were followed for 2 years from first oral anticoagulant prescription to first clinical event or death. Censoring was applied for treatment switching or discontinuation. RESULTS: Overall, a good balance of patients' covariates was obtained with every PS model tested. IPW was found to be the best performing method in assessing covariate balance when applied to subgroups with relatively large sample sizes (combined-DOACs versus warfarin). With the IPTW-IPCW approach, the treatment effect tends to be larger, but still in line with the treatment effect estimated using other PS methods. Covariate adjustment with PS in the outcome model performed well when applied to subgroups with smaller sample sizes (dabigatran versus warfarin), as this method does not require further reduction of sample size, and trimming or truncation of extreme weights. CONCLUSION: The choice of adequate PS methods may vary according to the characteristics of the data. If assumptions of unobserved confounding hold, multiple approaches should be identified and tested. PS based methods can be implemented using routinely collected linked data, thus supporting Health Technology decision-making.

Patient perception and treatment convenience of dabigatran versus vitamin K antagonist when used for stroke prophylaxis in atrial fibrillation: Real-world Evaluation of Long-term Anticoagulant Treatment Experience (RE-LATE) study.

PURPOSE: Dabigatran is a direct thrombin inhibitor approved for stroke prophylaxis in patients with non-valvular atrial fibrillation (NVAF). Real-world data about patient preference, satisfaction and convenience in patients in Asia are not available. The study aimed to explore the perception of patients with newly diagnosed NVAF regarding dabigatran versus vitamin K antagonists (VKAs), when used for stroke prevention. PATIENTS AND METHODS: This was a multinational, multicentre, non-interventional study involving 49 sites across 5 countries in South East Asia and South Korea where 934 patients newly diagnosed with NVAF were initiated on either dabigatran (N=591) or VKA (N=343). Data were collected at baseline and over two follow-up visits across 6 months. Treatment satisfaction and patient convenience were evaluated using the Perception on Anticoagulant Treatment Questionnaire-2 (PACT-Q2). RESULTS: The mean age of the patients was 65.9±10.4 years, and 64.2% were male. Mean CHA2DS2-VASc score was 2.4±1.5, and mean HAS-BLED score was 1.2±0.9. At baseline, patients initiated on dabigatran had higher stroke risk, bleeding risk, creatinine clearance and proportion of patients with concomitant illnesses compared with patients initiated on VKAs. Treatment convenience was perceived to be significantly better with dabigatran versus VKAs at visits 2 and 3 (p=0.0423 and 0.0287, respectively). Treatment satisfaction was significantly better with dabigatran compared with VKAs at visit 3 (p=0.0300). CONCLUSION: In this study, dabigatran is associated with better patient perception in terms of treatment convenience and satisfaction compared with VKAs when used for stroke prevention in newly diagnosed NVAF patients from South East Asia and South Korea. TRIAL REGISTRATION NUMBER: NCT02849509. PLAIN LANGUAGE SUMMARY: Patient satisfaction with dabigatran versus VKAs in South East Asia. Patients with atrial fibrillation are at high risk of stroke and require anticoagulants for stroke prevention. Two such anticoagulants are dabigatran and VKAs. We wanted to compare the extent of satisfaction and treatment convenience among newly diagnosed patients with atrial fibrillation from the South East Asian region when they were given either dabigatran or VKAs. Consenting patients filled out a standardised questionnaire called the PACT-Q2 over three visits after they were started on either dabigatran (591 patients) or VKAs (343 patients). We found that satisfaction and convenience were significantly higher when patients received dabigatran than when they received VKAs.

An emulated target trial analysis based on Medicare data suggested non-inferiority of Dabigatran versus Rivaroxaban.

OBJECTIVES: Rivaroxaban and Dabigatran were the first two non-vitamin K antagonist oral anticoagulants (NOACs) for preventing stroke among non-valvular Atrial Fibrillation patients. This article aimed to evaluate the relative efficacy and safety of Rivaroxaban versus Dabigatran. STUDY DESIGN AND SETTING: An emulated target trial analysis was conducted based on Medicare, in which we constructed three "randomized clinical trials" with well-defined inclusion/exclusion criteria, treatment regimens, and analysis procedures. We analyzed the individual trials, examined temporal variations, and generated unified results via pooled analysis. RESULTS: With a two-year data collection window (2012-2013), 70,129 subjects were enrolled in the three emulated trials, with 36,269 and 34,089 in the Rivaroxaban and Dabigatran arms, respectively. Dabigatran (the reference group for hazard ratio - HR) was superior regarding time to any primary event (including ischemic stroke, other thromboembolic events, major bleeding, and death; HR 1.232, P-value 0.0025), major bleeding (HR 1.187, P-value <0.0001), and mortality (HR 1.488, P-value <0.0001). Differences regarding stroke and other thromboembolic events were not significant. CONCLUSION: Dabigatran was found as superior for the Medicare patients with multiple chronic conditions. Temporal variations, which had been largely neglected in the literature, were observed. This study may provide new insight into treating AF with NOACs.

Frailty and Clinical Outcomes of Direct Oral Anticoagulants Versus Warfarin in Older Adults With Atrial Fibrillation : A Cohort Study.

BACKGROUND: The role of differing levels of frailty in the choice of oral anticoagulants for older adults with atrial fibrillation (AF) is unclear. OBJECTIVE: To examine the outcomes of direct oral anticoagulants (DOACs) versus warfarin by frailty levels. DESIGN: 1:1 propensity score-matched analysis of Medicare data, 2010 to 2017. SETTING: Community. PATIENTS: Medicare beneficiaries with AF who initiated use of dabigatran, rivaroxaban, apixaban, or warfarin. MEASUREMENTS: Composite end point of death, ischemic stroke, or major bleeding by frailty levels, defined by a claims-based frailty index. RESULTS: In the dabigatran-warfarin cohort (n = 158 730; median follow-up, 72 days), the event rate per 1000 person-years was 63.5 for dabigatran initiators and 65.6 for warfarin initiators (hazard ratio [HR], 0.98 [95% CI, 0.92 to 1.05]; rate difference [RD], -2.2 [CI, -6.5 to 2.1]). For nonfrail, prefrail, and frail persons, HRs were 0.81 (CI, 0.68 to 0.97), 0.98 (CI, 0.90 to 1.08), and 1.09 (CI, 0.96 to 1.23), respectively. In the rivaroxaban-warfarin cohort (n = 275 944; median follow-up, 82 days), the event rate per 1000 person-years was 77.8 for rivaroxaban initiators and 83.7 for warfarin initiators (HR, 0.98 [CI, 0.94 to 1.02]; RD, -5.9 [CI, -9.4 to -2.4]). For nonfrail, prefrail, and frail persons, HRs were 0.88 (CI, 0.77 to 0.99), 1.04 (CI, 0.98 to 1.10), and 0.96 (CI, 0.89 to 1.04), respectively. In the apixaban-warfarin cohort (n = 218 738; median follow-up, 84 days), the event rate per 1000 person-years was 60.1 for apixaban initiators and 92.3 for warfarin initiators (HR, 0.68 [CI, 0.65 to 0.72]; RD, -32.2 [CI, -36.1 to -28.3]). For nonfrail, prefrail, and frail persons, HRs were 0.61 (CI, 0.52 to 0.71), 0.66 (CI, 0.61 to 0.70), and 0.73 (CI, 0.67 to 0.80), respectively. LIMITATIONS: Residual confounding and lack of clinical frailty assessment. CONCLUSION: For older adults with AF, apixaban was associated with lower rates of adverse events across all frailty levels. Dabigatran and rivaroxaban were associated with lower event rates only among nonfrail patients. PRIMARY FUNDING SOURCE: National Institute on Aging.

Assessment of the Potential for Veverimer Drug-Drug Interactions.

Veverimer is a polymer being developed as a potential treatment of metabolic acidosis in patients with chronic kidney disease. Veverimer selectively binds and removes hydrochloric acid from the gastrointestinal tract, resulting in an increase in serum bicarbonate. Veverimer is not systemically absorbed, so potential drug-drug interactions (DDIs) are limited to effects on the absorption of other oral drugs through binding to veverimer in the gastrointestinal tract or increases in gastric pH caused by veverimer binding to hydrochloric acid. In in vitro binding experiments using a panel of 16 test drugs, no positively charged, neutral, or zwitterionic drugs bound to veverimer. Three negatively charged drugs (furosemide, aspirin, ethacrynic acid) bound to veverimer; however, this binding was reduced or eliminated in the presence of normal physiologic concentrations (100-170 mM) of chloride. Veverimer increased gastric pH in vivo by 1.5-3 pH units. This pH elevation peaked within 1 hour and had returned to baseline after 1.5-3 hours. Omeprazole did not alter the effect of veverimer on gastric pH. The clinical relevance of in vitro binding and the transient increase in gastric pH was evaluated in human DDI studies using two drugs with the most binding to veverimer (furosemide, aspirin) and two additional drugs with pH-dependent solubility effecting absorption (dabigatran, warfarin). None of the four drugs showed clinically meaningful DDI with veverimer in human studies. Based on the physicochemical characteristics of veverimer and results from in vitro and human studies, veverimer is unlikely to have significant DDIs. SIGNIFICANCE STATEMENT: Patients with chronic kidney disease, who are usually on many drugs, are vulnerable to drug-drug interactions (DDIs). The potential for DDIs with veverimer was evaluated based on the known site of action and physicochemical structure of the polymer, which restricts the compound to the gastrointestinal tract. Based on the findings from in vitro and human studies, we conclude that veverimer is unlikely to have clinically significant DDIs.

Quantitative Benefit-Risk Assessment of P-gp-Mediated Drug-Drug Interactions of Dabigatran Coadministered With Pharmacokinetic Enhancers in Patients With Renal Impairment.

Drug-drug interactions (DDIs) between dabigatran and ritonavir/cobicistat are of major concern in people living with HIV, particularly in those with impaired renal function, because they can result in increased dabigatran exposure and thus an increased risk of major bleeding events. However, the extent of this interaction and subsequent need for dose adjustment in subjects with varying degrees of renal function is currently not yet fully understood. To close this knowledge gap, we conducted an integrated population physiologically-based pharmacokinetic/pharmacodynamic analysis linking changes in dabigatran exposure due to DDIs and varying degrees of renal function to the probability of experiencing an ischemic stroke or major bleeding event within 1 year. The results of our analysis suggest that coadministration of dabigatran etexilate (dabigatran prodrug) and ritonavir/cobicistat should be avoided in subjects with severe renal impairment. A 2-hour dose separation or dabigatran etexilate dose reduction to 110 mg b.i.d. (twice daily) should be considered in subjects with moderate renal impairment when coadministered with ritonavir, while the dabigatran etexilate dose should be further reduced to 75 mg b.i.d. when coadministered with cobicistat. No dabigatran etexilate dose adjustment is needed in subjects with normal renal function receiving ritonavir, but dabigatran etexilate dose reduction to 110 mg b.i.d. should be considered when coadministered with cobicistat.

Switching across direct oral anticoagulants: a real-life-setting pilot prospective study.

AIMS: Crossover between direct oral anticoagulants (DOACs) has been underinvestigated, but happens frequently in clinical practice. The purpose of this study was to evaluate causes, rates and outcomes of a DOAC-to-DOAC switch. METHODS: Patients receiving their first DOAC prescription at the Anticoagulation Center, Cardiology Dept, Bologna-Bellaria Hospital in 2017-2018 were consecutively included and prospectively followed up. DOAC-to-DOAC switch was the main outcome; causes of switch (cardiovascular events and noncardiovascular drug-related adverse events) had direct biannual assessment before and after the switch. RESULTS: Among 300 patients enrolled (mean age = 79.3 years, mean follow-up = 1.5 years), with no difference in cardiovascular risk factors depending on index DOAC, 13% underwent DOAC-to-DOAC switch, minor bleeding and noncardiovascular adverse events being the most frequent causes. Dabigatran carried a three-fold increase in risk of switch compared with other DOACs, but the mean age of patients who switched was 83. Factors leading to switch resolved in 87% of cases afterwards. Annual rates of cardiovascular/noncardiovascular V events did not differ before and after the switch. CONCLUSION: DOAC-to-DOAC switch happens in 9% of patients using DOAC each year, and seems not to impact rates of cardiovascular events after switch. Dabigatran, in the elderly, might be associated with a higher risk of DOAC-to-DOAC switch. Further studies are needed to confirm the long-term safety and effectiveness of switching paradigm.

Monitoring the use of dabigatran etexilate for stroke prevention: compliance with renal function guidelines.

INTRODUCTION Dabigatran etexilate has become widely used in New Zealand, but information relating to when renal function monitoring is being undertaken is lacking. AIM To investigate if clinically appropriate renal function monitoring is being undertaken in New Zealand primary care for stroke prevention in non-valvular atrial fibrillation patients prescribed dabigatran etexilate. METHODS New Zealand non-valvular atrial fibrillation patients' prescription and primary care health data were extracted from national administrative databases for the period 1 July 2011 to 31 December 2015. The proportion of patients who had serum creatinine measurements at close proximity to treatment initiation and 12-months post initiation were assessed with 95% confidence intervals (CIs) and compared with Fisher's exact test. Log-rank tests for univariate analysis (gender, age, ethnicity and deprivation) effects on serum creatinine testing at dabigatran etexilate treatment initiation and 12-months post initiation were performed. RESULTS Overall, 1,948 patients who had been dispensed dabigatran etexilate with available primary care health data were identified. A total of 1,752 (89.9% [CI: 88.5-91.2]) patients had a renal function test at dabigatran etexilate initiation. There were 929 (72.8% [CI: 70.2-75.2]) patients who received ≥1 year supply of dabigatran etexilate and of these 207 (22.3% [CI: 19.6.6-25.1]) had a serum creatinine test 1 year after initiation. Demographic univariate analysis yielded insignificant log-rank tests for association with having serum creatinine measurements, except for Pacific Peoples. DISCUSSION There appears to be sub-optimal adherence to renal function monitoring for non-valvular atrial fibrillation patients who receive more than 12-months' treatment with dabigatran etexilate in New Zealand primary care.

Predictors of Bleeding in the Perioperative Anticoagulant Use for Surgery Evaluation Study.

Background In the PAUSE (Perioperative Anticoagulant Use for Surgery Evaluation) Study, a simple, standardized, perioperative interruption strategy was provided for patients with nonvalvular atrial fibrillation taking direct oral anticoagulants (DOACs). Our objective was to define the factors associated with perioperative bleeding. Methods and Results We analyzed bleeding as the composite of major and clinically relevant nonmajor bleeding. Putative predictors of bleeding, and preoperative DOAC level were prospectively collected during recruitment. We used stratified logistic regression models for analysis. All statistical analyses were performed in R version 3.6.0. There were 3007 patients requiring perioperative DOAC interruption. More than one third of the included patients underwent a high bleeding risk procedure. The 30-day rates of major and clinically relevant nonmajor bleeding were 3.02% in apixaban (n=1257), 2.84% in dabigatran (n=668), and 4.16% for rivaroxaban (n=1082). Multivariate analysis stratified by region found more bleeding for hypertension (odds ratio [OR], 1.79; 95% CI 1.07-2.99; P=0.027), and prior bleeding (OR, 1.71; 95% CI, 1.08-2.71; P=0.021). Surgical bleed risk classification (high- versus low-risk) as a predictor of bleeding was only significant in the univariate analysis. The prediction model for major and clinically relevant nonmajor bleeding had an area under the curve of 0.71, and the preoperative DOAC level did not improve the area under the curve of the model. Conclusions In patients treated with DOACs who required an elective surgery/procedure and were managed with standardized DOAC interruption and resumption, there we did not find reversible risk factors for bleeding, suggesting that adjustment of the PAUSE management protocol to mitigate against bleeding is not needed.

Dabigatrana para prevenção do acidente cerebral vascular em pacientes acima de 60 anos com fibrilação atrial não valvar que não conseguem permanecer na faixa terapêutica de razão normalizada internacional com varfarina e idarucizumabe para reversão do efeito anticoagulante da dabigatrana / Dabigatran for the prevention of stroke in patients over 60 years of age with non-valve atrial fibrillation who are able to remain in the therapeutic range of normal ratio international warfarin and idarucizumab for reversal of anticoagulant effect of dabigatran

INTRODUÇÃO: A fibrilação atrial (FA) é uma doença crônica que causa uma desordem do sistema de condução elétrica dos átrios (câmaras superiores do coração). A desordem leva a um ritmo cardíaco rápido e irregular, bem como a perda da contração correta dos átrios. A FA é caracterizada por sintomas como palpitações, dispneia e tontura. Além disso, a doença apresenta importante repercussão na qualidade de vida dos indivíduos, devido as consequências clínicas, principalmente pelos fenômenos tromboembólicos, especialmente, o AVC. O manejo da doença é baseado na melhoria dos sintomas, pelo controle de ritmo ou frequência cardíaca, e na prevenção dos fenômenos tromboembólicos (AVC). O tratamento pode incluir medicamentos como os antiagregantes plaquetários, ácido acetilsalicílico, antagonista da vitamina K, principalmente o derivado cumarínico varfarina, e os novos anticoagulantes orais (p.e, a dabigatrana), bem como os procedimentos de cardioversão, ablação por cateter, monitoramento cardíaco, dentre outros. PERGUNTAS DE PESQUISA: I) D

Assessment of direct oral anticoagulants administered as potentially inappropriate medications to elderly inpatients.

Background There is evidence that direct oral anticoagulants administered as potentially inappropriate medications increase the risk of bleeding and thromboembolic complications, which represent serious threats to human health. Objective To identify direct oral anticoagulants administered as potentially inappropriate medications for hospitalized patients aged ≥ 65 years in our hospital, and to determine associated factors and the correlation between potentially inappropriate medications and adverse reactions. Setting Xi'an Central Hospital, China. Method A retrospective cross-sectional study of elderly hospitalized patients who received either dabigatran or rivaroxaban at Xi'an Central Hospital between June 1, 2018 and June 1, 2019. The evaluation criteria of direct oral anticoagulants were formulated based on drug labels, disease guidelines and the 2019 American Geriatrics Society Beers Criteria, and any non-compliance with the criteria was considered to be potentially inappropriate medications. The Pearson chi-square test and a binary logistic regression model were used. Main outcome measure Factors associated with potentially inappropriate medications and correlation between potentially inappropriate medications and adverse reactions. Results This study analysed 315 patients aged ≥ 65 years. The application of our evaluation criteria identified 155 (49.2%) instances of potentially inappropriate medications, comprising 5 different types of potentially inappropriate medications. Fifteen adverse drug reactions occurred in the study participants. The Pearson chi-square test revealed significant differences in number of medications (p = 0.021) and creatinine clearance rate (p = 0.002) between potentially inappropriate medications and non-potentially inappropriate medications groups. In the binary logistic regression model, potentially inappropriate medications use was associated with creatinine clearance (creatinine clearance < 30: OR = 3.590, 95% CI = 1.214-10.615, p = 0.021), and there was no significant correlation between potentially inappropriate medications and adverse drug reactions after eliminating the confounding factors (age, length of hospitalization, number of disease combined) with p values of less than 0.25 (adjusted OR = 0.372, 95% CI = 0.117-1.182, p = 0.094). Conclusion This study revealed that the incidence of potentially inappropriate medications was relatively high, number of medications and creatinine clearance differed significantly between potentially inappropriate medications and non-potentially inappropriate medications groups, and potentially inappropriate medications was associated with creatinine clearance (creatinine clearance < 30 mL/min), but there was no significant correlation between potentially inappropriate medications and adverse drug reactions after eliminating the confounding factors.

Predicting Cost-Effectiveness of Generic vs. Brand Dabigatran Using Pharmacometric Estimates Among Patients with Atrial Fibrillation in the United States.

Generic entry of newer anticoagulants is expected to decrease the costs of atrial fibrillation management. However, when making switches between brand and generic medications, bioequivalence concerns are possible. The objectives of this study were to predict and compare the lifetime cost-effectiveness of brand dabigatran with hypothetical future generics. Markov microsimulations were modified to predict the lifetime costs and quality-adjusted life years of patients on either brand or generic dabigatran from a US private payer perspective. Event rates for generics were predicted using previously developed pharmacokinetic-pharmacodynamic models. The analyses showed that generic dabigatran with lower-than-brand systemic exposure were dominant. Meanwhile, generic dabigatran with extremely high systemic exposure was not cost-effective compared with the brand reference. Cost-effectiveness of generic medications cannot always be assumed as shown in this example. Combined use of pharmacometric and pharmacoeconomic models can assist in decision making between brand and generic pharmacotherapies.

Characteristics and outcomes in patients with atrial fibrillation receiving direct oral anticoagulants in off-label doses.

BACKGROUND: We evaluated adherence to dosing criteria for patients with atrial fibrillation (AF) taking dabigatran or rivaroxaban and the impact of off-label dosing on thromboembolic and bleeding risk. METHODS: We used data for a retrospective cohort from a large U.S. health plan for Medicare beneficiaries age > =65 years with AF who initiated dabigatran or rivaroxaban during 2010-2016. Stroke and major bleeding were quantified in patients who were eligible for low dose but received standard dose, and in patients who were eligible for standard dose but received low dose. RESULTS: We identified 8035 and 19,712 patients who initiated dabigatran or rivaroxaban, respectively. Overall, 1401 (17.4%) and 7820 (39.7%) patients who received dabigatran and rivaroxaban met criteria for low dose, respectively. Of those, 959 (68.5%) and 3904 (49.9%) received standard dose. In contrast, 1013 (15.3%) and 2551 (21.5%) of patients eligible for standard dose dabigatran and rivaroxaban received low dose. Mean follow-up for patients eligible for low and standard dose dabigatran and rivaroxaban were 13.9, 15.1, 10.1, and 12.3 months, respectively. In unadjusted analyses, patients eligible for low or standard dose dabigatran and rivaroxaban but receiving off-label dose, had no differences in the rates of ischemic stroke. Among patients who met criteria for standard dose direct oral anticoagulants (DOAC), use of low dose was associated with significantly higher risk of any major bleeding (Dabigatran: HR = 1.44; 95% CI 1.14-1.8, P = 0.002, Rivaroxaban HR 1.34, 95% CI 1.11-1.6, P = 0.002) and gastrointestinal bleeding (Dabigatran: HR = 1.48; 95% CI 1.08-2, P = 0.016). In patients who met criteria for low dose DOACs, there was lower risk of major bleeding (Dabigatran: HR = 0.59; 95% CI 0.43-0.8, P < 0.001), gastrointestinal (Rivaroxaban: HR 0.79; 95% CI 0.64-0.98, P = 0.03) and intracranial bleeding (Dabigatran: HR = 0.33; 95% CI 0.12-0.9, P = 0.001) with standard dosing. After propensity matching, use of off-label doses was not associated with stroke, major, gastrointestinal or intracranial bleeding for either dabigatran or rivaroxaban. CONCLUSIONS: While a significant number of patients receive higher or lower dose of dabigatran and rivaroxaban than recommended, we found no evidence of significant impact on thromboembolic or hemorrhagic outcomes.

Jurisdictional Guidance on DOAC Use-Will It Affect Practice? A Comparison of European, American, and Canadian Product Monographs.

Objective: To identify clinically relevant areas of concordance and discordance between product monographs for 4 direct oral anticoagulants (DOACs) approved by regulatory authorities in Europe, the United States, and Canada. Data Sources: For each DOAC (apixaban, dabigatran, edoxaban, rivaroxaban), manufacturer product monographs were retrieved from the European Medicines Database, US Food and Drug Administration, and Health Canada Drug Product Database. Data Extraction: Monographs for each DOAC were independently reviewed by 2 investigators to identify areas of concordance and discordance. Discordance existed if it was deemed that a potentially clinically relevant difference existed. A heat map summarizing the data was created to identify areas of complete concordance, partial concordance (concordance between 2 of 3 monographs), and complete discordance. Data Synthesis: The areas of concordance were indications for use, use in extremes of weight, and switching to/from the DOAC. Areas of discordance included the following: differing recommendations for use/dosing with renal dysfunction; contraindication or use with caution with drug interactions, pregnancy, and hepatic/renal dysfunction; and timing of DOAC with spinal/epidural anesthesia after a procedure or traumatic puncture. Relevance to Patient Care and Clinical Practice: Concordance was most evident for uncomplicated patients with atrial fibrillation or venous thromboembolism, whereas discordance emerged for those having characteristics/factors wherein clinicians may seek clarification within product monographs (eg, impaired renal/hepatic function, drug interactions). As such, clinicians must be familiar with product information within their country of practice. Conclusion: Variability between jurisdictions was evident, and variability of DOAC use is likely to increase with expanding worldwide uptake.

The contribution of real-world evidence to cost-effectiveness analysis: case study of Dabigatran etexilate in France.

OBJECTIVE: The goal of this study was to assess the differences between an ex ante and an ex post cost-effectiveness analysis of Dabigatran etexilate vs VKAs for the prevention of thromboembolic events in non-valvular atrial fibrillation patients and to draw lessons on the design and use of real-world data for decision making. METHODS: The same model was used to calculate the cost-effectiveness ratio using two sets of parameters. One set included the efficacy and safety outcomes data from RE-LY, the pivotal trial comparing Dabigatran to warfarin; cost data came from an ex ante publication. Outcomes data for the second set came from real-world data studies. Cost data were a mix of real-world data and other sources. Two treatment strategies were compared: treatment initiation by either Dabigatran or VKAs, followed by either VKAs or Dabigatran. A crude comparison of results was performed; the impact of data differences was then assessed. Probabilistic sensitivity results of the two analyses were compared. RESULTS: With real-world evidence, Dabigatran at both dosages was more effective for the prevention of ischemic strokes, intra-cranial haemorrhages, with less major extra-cranial haemorrhages and a similar risk of myocardial infarction. Using clinical trial data, Dabigatran150 mg (resp. Dabigatran110 mg) as a first-line treatment vs VKAs yielded an ICER of € 8077/QALY (resp. € 13,116/QALY). Real-world evidence scenarios were cost-saving and more effective for both dosages. CONCLUSION: The reassessment of outcomes and cost data had an impact on results, improving the efficiency of Dabigatran. We identify methodological issues which should be discussed if post-launch RWE based cost-effectiveness data become a standard in HTA decision making.

Comparisons between Oral Anticoagulants among Older Nonvalvular Atrial Fibrillation Patients.

OBJECTIVES: Older adult patients are underrepresented in clinical trials comparing non-vitamin K antagonist oral anticoagulants (NOACs) and warfarin. This subgroup analysis of the ARISTOPHANES study used multiple data sources to compare the risk of stroke/systemic embolism (SE) and major bleeding (MB) among very old patients with nonvalvular atrial fibrillation (NVAF) prescribed NOACs or warfarin. DESIGN: Retrospective observational study. SETTING: The Centers for Medicare & Medicaid Services and three US commercial claims databases. PARTICIPANTS: A total of 88 582 very old (aged ≥80 y) NVAF patients newly initiating apixaban, dabigatran, rivaroxaban, or warfarin from January 1, 2013, to September 30, 2015. MEASUREMENTS: In each database, six 1:1 propensity score matched (PSM) cohorts were created for each drug comparison. Patient cohorts were pooled from all four databases after PSM. Cox proportional hazards models were used to estimate hazard ratios (HRs) of stroke/SE and MB. RESULTS: The patients in the six matched cohorts had a mean follow-up time of 7 to 9 months. Compared with warfarin, apixaban (HR = .58; 95% confidence interval [CI] = .49-.69), dabigatran (HR = .77; 95% CI = .60-.99), and rivaroxaban (HR = .74; 95% CI = .65-.85) were associated with lower risks of stroke/SE. For MB, apixaban (HR = .60; 95% CI = .54-.67) was associated with a lower risk; dabigatran (HR = .92; 95% CI = .78-1.07) was associated with a similar risk, and rivaroxaban (HR = 1.16; 95% CI = 1.07-1.24) was associated with a higher risk compared with warfarin. Apixaban was associated with a lower risk of stroke/SE and MB compared with dabigatran (stroke/SE: HR = .65; 95% CI = .47-.89; MB: HR = .60; 95% CI = .49-.73) and rivaroxaban (stroke/SE: HR = .72; 95% CI = .59-.86; MB: HR = .50; 95% CI = .45-.55). Dabigatran was associated with a lower risk of MB (HR = .77; 95% CI = .67-.90) compared with rivaroxaban. CONCLUSION: Among very old NVAF patients, NOACs were associated with lower rates of stroke/SE and varying rates of MB compared with warfarin. J Am Geriatr Soc 67:1662-1671, 2019.

Effectiveness and safety of oral anticoagulants in older adults with non-valvular atrial fibrillation and heart failure.

Direct oral anticoagulants (DOACs) are at least as efficacious and safe as warfarin among non-valvular atrial fibrillation (NVAF) patients; limited evidence is available regarding NVAF patients with heart failure (HF). US Medicare enrollees with NVAF and HF initiating DOACs (apixaban, rivaroxaban, dabigatran) or warfarin were selected. Propensity score matching and Cox models were used to estimate the risk of stroke/systemic embolism (SE), major bleeding (MB), and major adverse cardiac events (MACE) comparing DOACs versus warfarin and DOACs versus DOACs. We identified 10,570 apixaban-warfarin, 4,297 dabigatran-warfarin, 15,712 rivaroxaban-warfarin, 4,263 apixaban-dabigatran, 10,477 apixaban-rivaroxaban, and 4,297 dabigatran-rivaroxaban matched pairs. Compared to warfarin, apixaban had lower rates of stroke/SE (hazard ratio = 0.64, 95% confidence interval = 0.48-0.85), MB (hazard ratio = 0.66, 0.58-0.76), and MACE (hazard ratio = 0.73,0.67-0.79); dabigatran and rivaroxaban had lower rates of MACE (hazard ratio = 0.87,0.77-0.99; hazard ratio = 0.84, 0.79-0.89, respectively). Rivaroxaban had a lower stroke/SE rate (hazard ratio = 0.65, 0.52-0.81) and higher MB rate (hazard ratio = 1.18, 1.08-1.30) versus warfarin. Compared to dabigatran and rivaroxaban, apixaban had lower MB (hazard ratio = 0.71, 0.57-0.89; hazard ratio = 0.55, 0.49-0.63) and MACE rates (hazard ratio = 0.80, 0.69-0.93; hazard ratio = 0.86, 0.79-0.94), respectively. All DOACs had lower MACE rates versus warfarin; differences were observed in stroke/SE and MB. Our findings provide insights about OAC therapy among NVAF patients with HF.

Dabigatrana para prevenção de acidente vascular cerebral em pacientes com fibrilação atrial não valvar e idarucizumabe para reversão do efeito anticoagulante do dabigatrana / Dabigatran for prevention of stroke in patients with non-valvular atrial fibrillation and idarucizumab for reversal of the anticoagulant effect of dabigatran

INTRODUÇÃO: A fibrilação atrial (FA) é uma doença crônica, que causa uma desordem do sistema de condução elétrica dos átrios (câmara superiores do coração), que leva a um ritmo cardíaco rápido e irregular, com perda da contração. A FA é caracterizada por sintomas como palpitações, dispneia e tontura. Apresenta importante repercussão na qualidade de vida (QV), em especial devido a suas consequências clínicas, principalmente nos fenômenos tromboembólicos e alterações cognitivas. O manejo da doença hoje é baseado na melhoria dos sintomas, pelo controle de ritmo ou frequência cardíaca, e a prevenção de fenômenos tromboembólicos. O tratamento pode incluir medicamentos (como os anticoagulantes orais), cardioversão, ablação por cateter, monitoramento cardíaco e algumas cirurgias (procedimento de Cox-Maze e procedimentos minimamente invasivos). TECNOLOGIAS: Dabigatrana e Idarucizumabe. PERGUNTA 1: Dabigatrana é eficaz e segura na prevenção de AVC em pacientes de FA que não permanecem na faixa terapêutica de RNI com varfarina? PERGUNTA 2: Idarucizumabe é eficaz e seguro na reversão do efeito anticoagulante de Pradaxa® (dabigatrana)? EVIDÊNCIAS CIENTÍFICAS: A evidência atualmente disponível sobre a eficácia e segurança da dabigatrana e do seu reversor o idarucizumabe para pacientes com FA não valvar, é baseada em ensaios clínicos. Para a dabigatrana um ensaio clínico randomizado aberto com controle ativo, a varfarina, e para o idarucizumabe um ensaio clínico aberto sem comparador. Na publicação conduzida por Biszewski et al., (2015) a dabigatrana, em ambas apresentações 110mg e 150mg, foi superior à varfarina para os desfechos AVC hemorrágico, sangramento maior taxa de mortalidade. Já para AVC e embolia pulmonar a dabigatrana foi superior na apresentação de 150mg e não inferior na apresentação de 110mg quando comparada a varfarina para a população total do estudo RE-LY. No entanto, alguns resultados de tempo na faixa terapêutica por centros participantes do estudo RE-LY(cTTR), não favoreceram ao tratamento com a dabigatrana, principalmente em cTTR >72,6%. O tratamento com dabigatrana 150mg esteve associada a um maior risco de desfechos negativos (p.e. total de mortes) em comparação a varfarina. Já para a dose de 110mg houve aumento de desfechos negativos (p.e. AVC não hemorrágico), também em centros participantes que permaneceram em faixas terapêuticas por mais tempo (cTTR >72,6%) em comparação a varfarina. Porém, a dabigatrana possui uma ligeira vantagem, estatisticamente significante, quando o cTTR dos é baixo (<57,1%). Salienta-se, que o proxycTTR, pode ter adicionado sérias limitações ao estudo, pois a avaliação dos dados individuais da razão normalizada internacional (RNI) dos pacientes poderia mostrar uma estimativa mais realista da eficácia, inclusive com os dados de descontinuação dos tratamentos. No segundo relato Wallentin et al., (2010), do estudo RE-LY, não foi possível avaliar de forma clara a influência do farmacêutico no controle do RNI dos pacientes tratados com dabigatrana vs. varfarina, que pudesse demonstrar algum resultado subestimado. Além disso, os resultados do TTR do RE-LY foram demonstrados em média e os da coorte em mediana, o que não permitiu uma comparação direta e análise mais aprofundada do fator de confundimento da profissional farmacêutico. O estudo RE-VERSE AD demonstrou benefício com o tratamento com o idarucizumabe. No grupo A, dos 203 restantes, 134 (67,7%) tinham confirmado a interrupção do sangramento em 24 horas, com média de 2,5 horas. Já para o grupo B foi de 1,6 hora e a hemostasia periprocedural foi avaliada como normal em 184 pacientes (93,4%), levemente anormal em dez pacientes (5,1%) e moderadamente anormal em três pacientes (1,5%), sendo que nenhum deles apresentou hemostasia gravemente anormal. No entanto, o estudo não apresenta um braço comparador com a varfarina e alguma prática atual (p.e. a transfusão sanguínea). AVALIAÇÃO ECONÔMICA: O demandante delineou em sua proposta um estudo de custoefetividade (RCEI) com varfarina e a dabigatrana. O estudo demonstrou RCEI de R$ 1.547,11 mil/QALY a R$6.388,64 mil por QALY ganho. Já para a o idarucizumabe em comparação às práticas atuais do SUS, o estudo indicou um RCEI de -R$ 29.431 por QALY para a análise de sangramento ameaçadores da vida e para cirurgias de emergências -R$52.505 por QALY. AVALIAÇÃO DE IMPACTO ORÇAMENTÁRIO: O impacto orçamentário do demandante mostrou um aporte de recurso de aproximadamente 40 milhões com a dabigatrana e para a idarucizumabe foi de aproximadamente R$ 266 mil, ambos em 5 anos. MONITORAMENTO DO HORIZONTE TECNOLÓGICO: Não foram localizados medicamentos no horizonte tecnológico para tratar pacientes com fibrilação atrial. Não foram localizados outros potenciais medicamentos para a reversão do efeito da dabigatrana em fase 3 ou 4 de pesquisa clínica. RECOMENDAÇÃO PRELIMINAR DA CONITEC: A CONITEC em sua 73ª reunião ordinária, no dia 05 de dezembro de 2018, recomendou a não incorporação no SUS da dabigatrana, bem como do seu reversor o idarucizumabe para pacientes com FA não valvar. Considerou-se que existem muitas incertezas nos resultados apresentados, pois foram apresentadas evidências indiretas sobre a eficácia do tratamento. CONSULTA PÚBLICA: A Consulta Pública nº 82/2018 foi realizada entre os dias 02/01/2019 a 21/01/2019. Foram recebidas 548 contribuições, 120 (22%) pelo formulário para contribuições técnico-científicas e 428 (78%) pelo formulário para contribuições sobre experiência ou opinião de pacientes, familiares, amigos ou cuidadores de pacientes, profissionais de saúde ou pessoas interessadas no tema. Das 120 contribuições de cunho técnico-científico, 93 (78%) discordaram totalmente, quatorze (12%) discordou parcialmente, uma (1%) contribuição concordou parcialmente e doze (10%) contribuições concordou totalmente com a recomendação preliminar da CONITEC. Das 428 contribuições sobre experiência ou opinião de pacientes, cerca de 370 (86%) discordou totalmente, 28 (7%) discordou parcialmente, quatro (1%) concordou parcialmente e 26 (6%) concordou totalmente com a recomendação preliminar da CONITEC. Após apreciação das contribuições encaminhadas pela consulta pública, o plenário recomendou a não incorporação da dabigatrana para prevenção de acidente vascular cerebral e do Idarucizumabe para reversão do efeito anticoagulante do dabigatrana. RECOMENDAÇÃO FINAL DA CONITEC: Os membros da CONITEC presentes na 74ª reunião ordinária, no dia 07 de fevereiro de 2019, deliberaram por unanimidade recomendar a não incorporação da dabigatrana para prevenção de acidente vascular cerebral e do Idarucizumabe para reversão do efeito anticoagulante do dabigatrana. Foi assinado o Registro de Deliberação nº 425/2019. DECISÃO: Não incorporar a dabigatrana para prevenção de acidente vascular cerebral e do idarucizumabe para reversão do efeito anticoagulante da dabigatrana, no âmbito do Sistema Único de Saúde ­ SUS. Dada pela Portaria nº 10, publicada no Diário Oficial da União nº 40, seção 1, página 55, em 26 de fevereiro de 2018.

Dabigatrana para prevenção de acidente vascular cerebral em pacientes com fibrilação atrial não valvar e Idarucizumabe para reversão do efeito anticoagulante do dabigatrana / Dabigatran for stroke prevention in patients with nonvalvular atrial fibrillation and Idarucizumab for reversal of the anabolic effect of dabigatran

INTRODUÇÃO: A fibrilação atrial (FA) é uma doença crônica, que causa uma desordem do sistema de condução elétrica dos átrios (câmara superiores do coração), que leva a um ritmo cardíaco rápido e irregular, com perda da contração. A FA é caracterizada por sintomas como palpitações, dispneia e tontura. Apresenta importante repercussão na qualidade de vida (QV), em especial devido a suas consequências clínicas, principalmente nos fenômenos tromboembólicos e alterações cognitivas. O manejo da doença hoje é baseado na melhoria dos sintomas, pelo controle de ritmo ou frequência cardíaca, e a prevenção de fenômenos tromboembólicos. O tratamento pode incluir medicamentos (como os anticoagulantes orais), cardioversão, ablação por cateter, monitoramento cardíaco e algumas cirurgias (procedimento de Cox-Maze e procedimentos minimamente invasivos). TECNOLOGIAS: Dabigatrana e Idarucizumabe. PERGUNTA 1: Dabigatrana é eficaz e segura na prevenção de AVC em pacientes de FA que não permanecem na faixa terapêutica de RNI com varfarina? PERGUNTA 2: Idarucizumabe é eficaz e seguro na reversão do efeito anticoagulante de Pradaxa® (dabigatrana)? EVIDÊNCIAS CIENTÍFICAS: A evidência atualmente disponível sobre a eficácia e segurança da dabigatrana e do seu reversor o idarucizumabe para pacientes com FA não valvar, é baseada em ensaios clínicos. Para a dabigatrana um ensaio clínico randomizado aberto com controle ativo, a varfarina, e para o idarucizumabe um ensaio clínico aberto sem comparador. Na publicação conduzida por Biszewski et al., (2015) a dabigatrana, em ambas apresentações 110mg e 150mg, foi superior à varfarina para os desfechos AVC hemorrágico, sangramento maior taxa de mortalidade. Já para AVC e embolia pulmonar a dabigatrana foi superior na apresentação de 150mg e não inferior na apresentação de 110mg quando comparada a varfarina para a população total do estudo RE-LY. No entanto, alguns resultados de tempo na faixa terapêutica por centros participantes do estudo RE-LY(cTTR), não favoreceram ao tratamento com a dabigatrana, principalmente em cTTR >72,6%. O tratamento com dabigatrana 150mg esteve associada a um maior risco de desfechos negativos (p.e. total de mortes) em comparação a varfarina. AVALIAÇÃO ECONÔMICA: O demandante delineou em sua proposta um estudo de custoefetividade (RCEI) com varfarina e a dabigatrana. O estudo demonstrou RCEI de R$ 1.547,11 mil/QALY a R$6.388,64 mil por QALY ganho. Já para a o idarucizumabe em comparação às práticas atuais do SUS, o estudo indicou um RCEI de -R$ 29.431 por QALY para a análise de sangramento ameaçadores da vida e para cirurgias de emergências -R$52.505 por QALY. AVALIAÇÃO DE IMPACTO ORÇAMENTÁRIO: O impacto orçamentário do demandante mostrou um aporte de recurso de aproximadamente 40 milhões com a dabigatrana e para a idarucizumabe foi de aproximadamente R$ 266 mil, ambos em 5 anos. MONITORAMENTO DO HORIZONTE TECNOLÓGICO: Não foram localizados medicamentos no horizonte tecnológico para tratar pacientes com fibrilação atrial. Não foram localizados outros potenciais medicamentos para a reversão do efeito da dabigatrana em fase 3 ou 4 de pesquisa clínica. RECOMENDAÇÃO PRELIMINAR DA CONITEC: A CONITEC em sua 73ª reunião ordinária, no dia 05 de dezembro de 2018, recomendou a não incorporação no SUS da dabigatrana, bem como do seu reversor o idarucizumabe para pacientes com FA não valvar. Considerou-se que existem muitas incertezas nos resultados apresentados, pois foram apresentadas evidências indiretas sobre a eficácia do tratamento. CONSULTA PÚBLICA: A Consulta Pública nº 82/2018 foi realizada entre os dias 02/01/2019 a 21/01/2019. Foram recebidas 548 contribuições, 120 (22%) pelo formulário para contribuições técnico-científicas e 428 (78%) pelo formulário para contribuições sobre experiência ou opinião de pacientes, familiares, amigos ou cuidadores de pacientes, profissionais de saúde ou pessoas interessadas no tema. Das 120 contribuições de cunho técnico-científico, 93 (78%) discordaram totalmente, quatorze (12%) discordou parcialmente, uma (1%) contribuição concordou parcialmente e doze (10%) contribuições concordou totalmente com a recomendação preliminar da CONITEC. Das 428 contribuições sobre experiência ou opinião de pacientes, cerca de 370 (86%) discordou totalmente, 28 (7%) discordou parcialmente, quatro (1%) concordou parcialmente e 26 (6%) concordou totalmente com a recomendação preliminar da CONITEC. Após apreciação das contribuições encaminhadas pela consulta pública, o plenário recomendou a não incorporação da dabigatrana para prevenção de acidente vascular cerebral e do Idarucizumabe para reversão do efeito anticoagulante do dabigatrana. RECOMENDAÇÃO FINAL DA CONITEC: Os membros da CONITEC presentes na 74ª reunião ordinária, no dia 07 de fevereiro de 2019, deliberaram por unanimidade recomendar a não incorporação da dabigatrana para prevenção de acidente vascular cerebral e do Idarucizumabe para reversão do efeito anticoagulante do dabigatrana. Foi assinado o Registro de Deliberação nº 425/2019. DECISÃO: Não incorporar a dabigatrana para prevenção de acidente vascular cerebral e do idarucizumabe para reversão do efeito anticoagulante da dabigatrana, no âmbito do Sistema Único de Saúde ­ SUS. Dada pela Portaria nº 10, publicada no Diário Oficial da União nº 40, seção 1, página 55, em 26 de fevereiro de 2018.

Comparison of all-cause, stroke, and bleed-specific healthcare resource utilization among patients with non-valvular atrial fibrillation (NVAF) and newly treated with dabigatran or warfarin.

BACKGROUND: We compared healthcare utilization outcomes and persistence among non-valvular atrial fibrillation (NVAF) patients newly treated with dabigatran or warfarin. METHODS: Using a nationwide, US administrative claims database, a retrospective matched-cohort of newly diagnosed NVAF patients (age≥18 years) treated with dabigatran or warfarin (propensity score matched 1:1) in 01/01/2011-12/31/2013 was evaluated. All-cause, stroke-, and bleed-specific per patient per month (PPPM) healthcare resource utilization (HCRU), incidence rate of hospitalization for stroke or bleed, 30-day readmission, and persistence were reported. RESULTS: In total, 18,890 dabigatran patients were matched to corresponding warfarin patients. Compared to warfarin users, dabigatran users PPPM had significantly fewer all-cause hospitalizations (0.04 vs 0.05), total outpatient visits (3.98 vs 5.87), and lower 30-day readmissions (14.5% vs 17.4%, all p < 0.001). Dabigatran users had lower incidence rate for stroke (0.65 vs 1.06) and bleed (1.69 vs 2.20), stroke (0.0006 vs 0.0011, p < 0.001) and bleed-specific hospitalizations (0.002 vs 0.003, p = 0.008), and stroke (0.03 vs 0.04, p < 0.001) and bleed-specific outpatient visits (0.07 vs 0.08, p = 0.018), and significantly lower non-persistence (62.1% vs 66.3%, p < 0.001). CONCLUSION: Among newly diagnosed newly treated NVAF patients, dabigatran users had significantly lower all-cause, stroke- and bleed-specific HCRU, lower risk of hospitalization for stroke or bleed events, lower 30-day readmissions, and higher persistence than warfarin users.