Payer approval and rejection of oral anticoagulant prescriptions and prescription abandonment patterns among patients with venous thromboembolism

BACKGROUND

Venous thromboembolism (VTE) is a major public health condition that renders patients at risk of recurrent events, which significantly increases their morbidity, mortality, and health care costs. Apart from warfarin, direct oral anticoagulants, such as apixaban, dabigatran, or rivaroxaban, are approved for VTE treatment. Cardiovascular drugs are largely impacted by formulary restrictions; however, the impact on oral anticoagulants (including warfarin and direct oral anticoagulants) in VTE has not been well studied.

OBJECTIVE

To describe the extent of payer-rejected claims for oral anticoagulants for VTE and the factors associated with rejected claims. Prescription abandonment of oral anticoagulants and the time to an eventual fill for oral anticoagulant after rejection or abandonment were also evaluated.

METHODS

A retrospective cohort study was conducted among patients with VTE newly prescribed an oral anticoagulant (first claim was the index) between October 2016 and October 2021. Descriptive statistics were used to describe the proportion of patients with paid (ie, filled), rejected, or abandoned index oral anticoagulant prescription and journey to paid prescription among those with initial rejection. Multivariable logistic regression was used to identify factors associated with initial rejection.

RESULTS

Among the overall sample (N = 297,312), 74.3% had initial oral anticoagulant prescriptions approved, 9.1% had them rejected, and 16.7% abandoned them. Of the patients with initial rejection, 82.1% eventually filled their oral anticoagulant prescriptions; however, for 14.2% of these patients, the first fill was for an oral anticoagulant other than that initially prescribed. The mean time to a first fill for an oral anticoagulant after an initial rejection was 18.3 days. More than half of the patients with an initial rejected oral anticoagulant claim had at least 1 additional rejection during the follow-up period. Of the patients who abandoned their initial oral anticoagulant prescription, 83.9% filled an oral anticoagulant prescription during follow-up; the mean time to fill for the index oral anticoagulant was 15.6 days. Oral anticoagulant type, Medicare payer coverage, prescribing physician specialty, and VTE diagnosis setting of care were significantly associated with index oral anticoagulant claim rejection (P < 0.05).

CONCLUSIONS

Rejection and abandonment may delay access to oral anticoagulant treatment. Factors contributing to these scenarios should be understood and addressed for proper VTE management.

Temporal trends in anticoagulation use and clinical outcomes among medicare beneficiaries with non-valvular atrial fibrillation

PURPOSE

Oral anticoagulants effectively prevent stroke/systemic embolism among patients with non-valvular atrial fibrillation but remain under-prescribed. This study evaluated temporal trends in oral anticoagulant use, the incidence of stroke/systemic embolism and major bleeding, and economic outcomes among elderly patients with non-valvular atrial fibrillation and CHA2DS2-VASc scores ≥ 2.

METHODS

Retrospective analyses were conducted on Medicare claims data from January 1, 2012 through December 31, 2017. Non-valvular atrial fibrillation patients aged ≥ 65 years with CHA2DS2-VASc scores ≥ 2 were stratified by calendar year (2013-2016) of care to create calendar-year cohorts. Patient characteristics were evaluated across all cohorts during the baseline period (12 months before diagnosis). Treatment patterns and clinical and economic outcomes were evaluated during the follow-up period (from diagnosis through 12 months).

RESULTS

Baseline patient characteristics remained generally similar between 2013 and 2016. Although lack of oral anticoagulant prescriptions among eligible patients remained relatively high, utilization did increase progressively (53-58%). Among treated patients, there was a progressive decrease in warfarin use (79-52%) and a progressive increase in overall direct oral anticoagulant use (21-48%). There were progressive decreases in the incidence of stroke/systemic embolism 1.9-1.4 events per 100 person years) and major bleeding (4.6-3.3 events per 100 person years) as well as all-cause costs between 2013 and 2016.

CONCLUSIONS

The proportions of patients with non-valvular atrial fibrillation who were not prescribed an oral anticoagulant decreased but remained high. We observed an increase in direct oral anticoagulant use that coincided with decreased incidence of clinical outcomes as well as decreasing total healthcare costs.

A Real-World Evaluation of Primary Medication Nonadherence in Patients with Nonvalvular Atrial Fibrillation Prescribed Oral Anticoagulants in the United States

BACKGROUND

Nonadherence to oral anticoagulants (OACs) is a challenge to stroke risk reduction in patients with nonvalvular atrial fibrillation (NVAF). Data on primary medication nonadherence (PMN) in NVAF are lacking.

OBJECTIVES

Our aim was to assess the rates and predictors of PMN among NVAF patients who were newly prescribed an OAC.

METHODS

This was a retrospective database analysis of linked healthcare claims and electronic health record data. Adult NVAF patients with a prescription order for an OAC (apixaban, rivaroxaban, dabigatran, or warfarin) between January 2016 and June 2019 were identified (date of first prescription order = index date). Patients had a 1-year baseline and a 6-month post-index period to assess the rates of PMN, defined as having a prescription order but no paid claim for any OAC on or within 30 days after the index date. Sensitivity analyses explored 60-, 90- and 180-day PMN thresholds. Logistic regression models were used to examine the predictors of PMN.

RESULTS

Among 20,393 patients, the overall 30-day PMN rate was 28.4%; PMN rates decreased to 17% with a 180-day threshold. PMN was numerically lowest for warfarin among OACs and numerically lowest for apixaban among direct OACs. A CHA2DS2-VASc score of ≥ 3, commercial insurance, and African American race were associated with higher odds of PMN.

CONCLUSIONS

More than one-quarter of patients experienced PMN within 30 days of their initial prescription order. This rate decreased over a longer period, suggesting a delay in fills. Understanding the factors associated with PMN is warranted to develop effective interventions for improving OAC treatment rates in NVAF.

Effectiveness and Safety of Direct Oral Anticoagulants Among Patients with Non-valvular Atrial Fibrillation and Multimorbidity

INTRODUCTION

In the USA, there is a steady rise of atrial fibrillation due to the aging population with increased morbidity. This study evaluated the risk of stroke/systemic embolism (S/SE) and major bleeding (MB) among elderly patients with non-valvular atrial fibrillation (NVAF) and multimorbidity prescribed direct oral anticoagulants (DOACs).

METHODS

Using the CMS Medicare database, a retrospective observational study of adult patients with NVAF and multimorbidity who initiated apixaban, dabigatran, or rivaroxaban from January 1, 2012 to December 31, 2017 was conducted. High multimorbidity was classified as having ≥ 6 comorbidities. Cox proportional hazard models were used to evaluate the hazard ratios of S/SE and MB among three 1:1 propensity score matched DOAC cohorts. All-cause healthcare costs were estimated using generalized linear models.

RESULTS

Overall 36% of the NVAF study population had high multimorbidity, forming three propensity score matched (PSM) cohorts: 12,511 apixaban-dabigatran, 60,287 apixaban-rivaroxaban, and 12,567 dabigatran-rivaroxaban patients. Apixaban was associated with a lower risk of stroke/SE and MB when compared with dabigatran and rivaroxaban. Dabigatran had a lower risk of stroke/SE and a similar risk of MB when compared with rivaroxaban. Compared to rivaroxaban, apixaban patients incurred lower all-cause healthcare costs, and dabigatran patients incurred similar all-cause healthcare costs. Compared to dabigatran, apixaban patients incurred similar all-cause healthcare costs.

CONCLUSION

Patients with NVAF and ≥ 6 comorbid conditions had significantly different risks for stroke/SE and MB when comparing DOACs to DOACs, and different healthcare expenses. This study's results may be useful for evaluating the risk-benefit ratio of DOAC use in patients with NVAF and multimorbidity.

Contemporary prevalence estimates of undiagnosed and diagnosed atrial fibrillation in the United States

BACKGROUND

Atrial fibrillation (AF) prevalence estimates vary and have been based on cohorts with clinically established or diagnosed disease. Undiagnosed AF prevalence estimates are less certain as they are based on nongeneralizable convenience samples.

HYPOTHESIS

Because AF is often asymptomatic, it my remain undiagnosed until the development of complications such as stroke or heart failure. Consequently, the observed prevalence of diagnosed AF from the literature may underestimate total disease burden. We therefore sought to estimate the total prevalence of both diagnosed and undiagnosed AF.

METHODS

We performed a retrospective cohort study from 2012 to 2017 using data from five US medical claims data sets. Undiagnosed AF prevalence was estimated based on the observed incidence of ischemic stroke, systemic embolism (SE), and AF incidence after a stroke/SE. The diagnosed AF cohort included AF patients between Q1 2014 and Q3 2015. The undiagnosed AF cohort were patients with assumed undiagnosed AF in the year before a stroke/SE and who were newly diagnosed with AF in the 3-month poststroke/SE. Stroke/SE incidence was calculated among all AF patients and the ratio of number of undiagnosed AF patients to stroke rate was created. Age- and sex-adjusted estimates were stratified by period of assumed undiagnosed AF before poststroke/SE AF diagnosis (1 or 2 years).

RESULTS

The estimated US prevalence of AF (diagnosed and undiagnosed) in Q3 2015 was 5 628 000 cases, of which 591 000 cases (11%) were undiagnosed. The assumed 2-year undiagnosed AF prevalence was 23% (1 531 000) of the total prevalent patients with AF (6 568 000). Undiagnosed (vs. diagnosed) AF patients were older and had higher CHA2DS2-VASc scores. Of undiagnosed AF, 93% had CHA2DS2-VASc ≥2 and met OAC criteria.

CONCLUSIONS

These contemporary estimates demonstrate the high prevalence of undiagnosed AF in the United States. Undiagnosed AF patients are composed of primarily elderly individuals who if diagnosed, would meet criteria for stroke prevention therapy.

Warfarin Time in Therapeutic INR Range and Direct Oral Anticoagulant Adherence for Venous Thromboembolism Across the Spectrum of Weight and Body Mass Index: Findings from Veterans Health Administration

The evidence of direct oral anticoagulants (DOACs) usage for venous thromboembolism (VTE) in patients at extremes of body weight or mass index is limited. In such situations, warfarin may be more frequently used. We investigated warfarin time in the therapeutic international normalized ratio range (TTR) and DOAC adherence based on the calculated proportion of days covered (PDC) by pill coverage from a DOAC prescription in patients with VTE across all body sizes. Using data from the Veterans Health Administration (VA), we identified first-time patients with VTE between 2013 and 2018 treated with warfarin or DOACs. We analyzed 28,245 patients with warfarin TTR (N  =  10,167) or DOAC PDC(N  =  18,078). For warfarin-treated patients after index VTE, mean TTR was lower over shorter treatment durations (TTR 30 vs TTR 180 [mean  ±  SD]: 43.8% ± 33.5% vs 58.8% ± 23.5%). Mean TTR over 180 days after VTE was lowest for patients <60 kg (TTR 180 [mean  ±  SD]: <60kg: 49.3% ± 24.2% vs ≥60 to <100 kg: 57.8% ± 23.4%; P < .0001). For DOAC-treated patients over 180 days after index VTE, mean PDC was lowest for patients <60 kg (PDC 180 [mean  ±  SD]: < 60kg: 76.9% ± 33.2% vs ≥ 60 to <100 kg: 83.6% ± 27.7%; P < .0001).Most DOAC-treated patients attained sufficient adherence across the body size spectrum while warfarin-treated patients <60kg were at risk for low TTR.

Risk Levels and Adverse Clinical Outcomes Among Patients With Nonvalvular Atrial Fibrillation Receiving Oral Anticoagulants

IMPORTANCE

The CHA2DS2-VASc score (calculated as congestive heart failure, hypertension, age 75 years and older, diabetes, stroke or TIA, vascular disease, age 65 to 74 years, and sex category) is the standard for assessing risk of stroke and systemic embolism and includes age and thromboembolic history. To our knowledge, no studies have comprehensively evaluated safety and effectiveness outcomes among patients with nonvalvular atrial fibrillation receiving oral anticoagulants according to independent, categorical risk strata.

OBJECTIVE

To evaluate the incidence of key adverse outcomes among patients with nonvalvular atrial fibrillation receiving oral anticoagulants by CHA2DS2-VASc risk score range, thromboembolic event history, and age group.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study was a retrospective claims data analysis using combined data sets from 5 large health claims databases. Eligible participants were adult patients with nonvalvular atrial fibrillation who initiated oral anticoagulants. Data were analyzed between January 2012 and June 2019.

EXPOSURE

Initiation of oral anticoagulants.

MAIN OUTCOMES AND MEASURES

We observed clinical outcomes (including stroke or systemic embolism, major bleeding, and a composite outcome) on treatment through study end, censoring for discontinuation of oral anticoagulants, death, and insurance disenrollment. The population was stratified by CHA2DS2-VASc risk score; history of stroke, systemic embolism, or transient ischemic attack; and age groups. We calculated time to event, incidence rates, and cumulative incidence for outcomes.

RESULTS

We identified 1 141 097 patients with nonvalvular atrial fibrillation; the mean (SD) age was 75.0 (10.5) years, 608 127 patients (53.3%) were men, and over 1 million were placed in the 2 highest risk categories (high risk 1, 327 766 participants; high risk 2, 688 449 participants). Deyo-Charlson Comorbidity Index scores ranged progressively alongside CHA2DS2-VASc risk score strata (mean [SD] scores: low risk, 0.4 [1.0]; high risk 2, 4.1 [2.9]). The crude incidence of stroke and systemic embolism generally progressed alongside risk score strata (low risk, 0.25 events per 100 person-years [95% CI, 0.18-0.34 events]; high risk 2, 3.43 events per 100 person-years [95% CI, 3.06-4.20 events]); patients at the second-highest risk strata with thromboembolic event history had higher stroke incidence vs patients at the highest risk score strata without event history (2.06 events per 100 person-years [95% CI, 2.00-3.12 events] vs 1.18 events per 100 person-years [95% CI, 1.14-1.30 events]). Major bleeding and composite incidence also increased progressively alongside risk score strata (major bleeding: low risk, 0.68 events per 100 person-years [95% CI, 0.56-0.82 events]; high risk 2, 6.29 events per 100 person-years [95% CI, 6.21-6.62 events]; composite incidence: 1.22 events per 100 person-years [95% CI, 1.06-1.41 events]; high risk 2, 10.67 events per 100 person-years [95% CI, 10.26-11.48 events]). The 12-month cumulative incidence proportions for stroke and systemic embolism, major bleeding, and composite outcomes progressed alongside risk score strata (stroke or systemic embolism, 0.30%-1.85%; major bleeding, 0.55%-5.55%; composite, 1.05%-8.23%). Age subgroup analysis followed similar trends.

CONCLUSIONS AND RELEVANCE

The observed incidence of stroke or systemic embolism and major bleeding events generally conformed to an expected increasing incidence by risk score, adding insight into the importance of specific risk score range, thromboembolic event history, and age group strata. These results can help inform clinical decision-making, research, and policy.

Oral anticoagulant underutilization among elderly patients with atrial fibrillation: insights from the United States Medicare database

BACKGROUND

Oral anticoagulants (OACs) mitigate stroke risk in patients with atrial fibrillation (AF). The study aim was to analyze prevalence and predictors of OAC underutilization.

METHODS

Newly diagnosed AF patients with a CHA₂DS₂-VASc score ≥ 2 were identified from the US CMS Database (January 1, 2013-December 31, 2017). Patients were stratified based on having an OAC prescription versus not and the OAC prescription group was stratified by direct OAC (DOACs) versus warfarin. Multivariable logistic regression models were used to examine predictors of OAC underutilization.

RESULTS

Among 1,204,507 identified AF patients, 617,611 patients (51.3%) were not prescribed an OAC during follow-up (mean: 2.4 years), and 586,896 patients (48.7%) were prescribed an OAC during this period (DOAC: 388,629 [66.2%]; warfarin: 198,267 [33.8%]). Age ≥ 85 years (odds ratio [OR] 0.55, 95% confidence interval [CI] 0.55-0.56), female sex (OR 0.96, 95% CI 0.95-0.96), Black race (OR 0.78, 95% CI 0.77-0.79) and comorbidities such as gastrointestinal (GI; OR 0.43, 95% CI 0.41-0.44) and intracranial bleeding (OR 0.29, 95% CI 0.28-0.31) were associated with lower utilization of OACs. Furthermore, age ≥ 85 years (OR 0.92, 95% CI 0.91-0.94), Black race (OR 0.78, 95% CI 0.76-0.80), ischemic stroke (OR 0.77, 95% CI 0.75-0.80), GI bleeding (OR 0.73, 95% CI 0.68-0.77), and intracranial bleeding (OR 0.72, 95% CI 0.65-0.80) predicted lower use of DOACs versus warfarin.

CONCLUSIONS

Although OAC therapy prescription is the standard of care for stroke prevention in AF patients, its overall utilization is still low among Medicare patients ≥ 65 years old, with specific patient characteristics that predict underutilization.

Apixaban Use in Obese Patients: A Review of the Pharmacokinetic, Interventional, and Observational Study Data

Abstract

Relatively little is known about the influence of extreme body weight on the pharmacokinetics (PK), pharmacodynamics (PD), efficacy, and safety of drugs used in many disease states. While direct oral anticoagulants (DOACs) have an advantage over warfarin in that they do not require routine drug monitoring, some may regard this convenience as less compelling in obese patients. Some consensus guidelines discourage using DOACs in patients weighing > 120 kg or with a body mass index > 35–40 kg/m², given a sparsity of available data in this population and the concern that fixed dosing in obese patients might lead to decreased drug exposure and lower efficacy. Per the prescribing information, apixaban does not require dose adjustment in patients weighing above a certain threshold (e.g., ≥ 120 kg). Data from healthy volunteers and patients with nonvalvular atrial fibrillation (NVAF) or venous thromboembolism (VTE) have shown that increased body weight has a modest effect on apixaban’s PK. However, the paucity of exposure data in individuals > 120 kg and the lack of guideline consensus on DOAC use in obese patients continue to raise concerns about potential decreased drug exposure at extreme weight. This article is the first to comprehensively review the available PK data in obese individuals without NVAF or VTE, and PK, PD, efficacy, effectiveness, and safety data for apixaban in obese patients with either NVAF or VTE, including subgroup analyses across randomized controlled trials and observational (real-world) studies. These data suggest that obesity does not substantially influence the efficacy, effectiveness, or safety of apixaban in these patients.

Trial Registration ARISTOTLE: NCT00412984; AVERROES: NCT00496769; AMPLIFY: NCT00643201; AMPLIFY-EXT: NCT00633893; ADVANCE-1: NCT00371683; ADVANCE-2: NCT00452530; ADVANCE-3: NCT00423319

Video abstract

Non-persistence to Oral Anticoagulation Treatment in Patients with Non-valvular Atrial Fibrillation in the USA

BACKGROUND

Studies have shown that patients with non-valvular atrial fibrillation (NVAF) who discontinue oral anticoagulants (OACs) are at higher risk of complications such as stroke.

OBJECTIVE

This analysis compared the risk of non-persistence with OACs among patients with NVAF.

METHODS

Adult patients with NVAF who initiated apixaban, dabigatran, rivaroxaban, or warfarin were identified using 01JAN2013-30JUN2019 data from Centers for Medicare and Medicaid Services and four US commercial claims databases. Non-persistence was defined as discontinuation (no evidence of index OAC use for ≥ 60 days from the last days' supply) or switch to another OAC. Kaplan-Meier curves were generated to illustrate time to non-persistence along with cumulative incidences of non-persistence. Baseline and time-varying covariates were evaluated, and adjusted Cox proportional hazards models were used to evaluate non-persistence risk.

RESULTS

In total, 363,823 patients receiving apixaban, 57,121 receiving dabigatran, 282,831 receiving rivaroxaban, and 317,337 receiving warfarin were included. Of these, 47-72% discontinued/switched OAC therapy within an average 9-month follow-up. Apixaban was associated with a lower risk of non-persistence than were dabigatran (hazard ratio [HR] 0.62; 95% confidence interval [CI] 0.61-0.62), rivaroxaban (HR 0.76; 95% CI 0.75-0.76), and warfarin (HR 0.74; 95% CI 0.74-0.75). Dabigatran was associated with a higher risk of non-persistence than were warfarin (HR 1.21; 95% CI 1.19-1.22) and rivaroxaban (HR 1.23; 95% CI 1.22-1.25), and rivaroxaban was associated with a lower risk of non-persistence than was warfarin (HR 0.98; 95% CI 0.97-0.98). Clinical events (stroke/systemic embolism and major bleeding [MB]) during follow-up were predictors of non-persistence (stroke HR 1.57; 95% CI 1.53-1.61; MB HR 2.96; 95% CI 2.92-3.00).

CONCLUSION

In over one million patients with NVAF, our results suggest differences in anticoagulation treatment persistence across OAC agents, even after accounting for clinical events after OAC initiation. It is important for clinicians and patients to take these differences into consideration, especially as non-persistence to OAC therapy is associated with thromboembolic complications.

Real-world evidence comparing oral anticoagulants in non-valvular atrial fibrillation: a systematic review and network meta-analysis

Aim: To compare real-world effectiveness/safety of non-vitamin K antagonist oral anticoagulants and vitamin K antagonists among patients with non-valvular atrial fibrillation. Materials & methods: A systematic review of electronic databases yielded 7661 citations published from January 2013 to January 2020. Fifty-five studies were included in Bayesian network meta-analyses of hazard ratios. Results & conclusion: In comparison with vitamin K antagonists, apixaban, dabigatran and rivaroxaban were associated with a reduced risk of stroke or systemic embolism, ischemic stroke, intracranial hemorrhage and all-cause mortality. Apixaban, dabigatran and edoxaban, but not rivaroxaban, were associated with a reduced risk of major bleeding. This study confirmed the effectiveness and safety of non-vitamin K antagonist oral anticoagulants for the treatment of non-valvular atrial fibrillation in real-world settings, consistent with clinical trial evidence.

Contemporary clinical and economic outcomes among oral anticoagulant treated and untreated elderly patients with atrial fibrillation: Insights from the United States Medicare database

Background

Oral anticoagulants (OACs) mitigate the risk of stroke in atrial fibrillation (AF) patients.

Objective

Elderly AF patients who were treated with OACs (apixaban, dabigatran, edoxaban, rivaroxaban, or warfarin) were compared against AF patients who were not treated with OACs with respect to their clinical and economic outcomes.

Methods

Newly diagnosed AF patients were identified between January 2013 and December 2017 in the Medicare database. Evidence of an OAC treatment claim on or after the first AF diagnosis was used to classify patients into treatment-defined cohorts, and these cohorts were further stratified based on the initial OAC prescribed. The risks of stroke/systemic embolism (SE), major bleeding (MB), and death were analyzed using inverse probability treatment weighted time-dependent Cox regression models, and costs were compared with marginal structural models.

Results

The two treatment groups were composed of 1,421,187 AF patients: OAC treated (N = 583,350, 41.0% [36.4% apixaban, 4.9% dabigatran, 0.1% edoxaban, 26.7% rivaroxaban, and 31.9% warfarin patients]) and untreated (N = 837,837, 59.0%). OAC-treated patients had a lower adjusted risk of stroke/SE compared to untreated patients (hazard ratio [HR]: 0.70; 95% confidence interval [CI]: 0.68–0.72). Additionally patients receiving OACs had a lower adjusted risk of death (HR: 0.56; 95% CI: 0.55–0.56) and a higher risk of MB (HR: 1.57; 95% CI: 1.54–1.59) and this trend was consistent across each OAC sub-group. The OAC-treated cohort had lower adjusted total healthcare costs per patient per month ($4,381 vs $7,172; p < .0001).

Conclusion

For the OAC-treated cohort in this elderly US population, stroke/SE and all-cause death were lower, while risk of MB was higher. Among OAC treated patients, total healthcare costs were lower than those of the untreated cohort.

Effectiveness and Safety of Apixaban Versus Warfarin in Obese Patients with Nonvalvular Atrial Fibrillation Enrolled in Medicare and Veteran Affairs

Real-world studies have evaluated the use of anticoagulants in obese patients with nonvalvular atrial fibrillation (NVAF), but they have been limited by sample size or the use of diagnosis codes on claims to define obesity. This retrospective study used body weight data of ≥100 kg or a body mass index of ≥30 kg/m² to identify elderly (aged ≥65 years) NVAF patients with obesity in dually enrolled Veterans Affairs and fee-for-service Medicare patients. It evaluated the risk of stroke/systemic embolism (SE) and major bleeding (MB) in patients that initiated apixaban versus warfarin. Stabilized inverse probability treatment weighting was used to balance the baseline characteristics between patients prescribed apixaban and warfarin in obese patients. Cox models were used to evaluate the relative risk of stroke/SE and MB. Overall, 35.9% (n = 26,522) of the NVAF population were obese, of which 13,604 apixaban and 12,918 warfarin patients were included. After inverse probability treatment weighting, patient characteristics were balanced. The mean age was 75 years, the mean CHA₂DS₂-VASc score (Congestive Heart Failure, Hypertension, Age ≥75 [Doubled], Diabetes Mellitus, Prior Stroke or Transient Ischemic Attack [Doubled], Vascular Disease, Age 65-74, Female) was 3.8, the mean HAS-BLED (Hypertension, Abnormal Renal/Liver Function, Stroke, Bleeding History or Predisposition, Labile INR, Elderly, Drugs/Alcohol Concomitantly) Score was ∼2.6, and >98% of patients were males. Obese apixaban patients were associated with a similar risk of stroke/SE (hazard ratio: 0.82; 95% confidence interval: 0.66 to 1.03) and a significantly lower risk of MB (hazard ratio: 0.62; 95% confidence interval: 0.54 to 0.70) versus warfarin. No significant interaction was observed between treatment and obesity status (nonobese, obese/nonmorbid, obese/morbid) for stroke/SE (interaction p = 0.602) or MB (interaction p = 0.385). In obese patients with NVAF, apixaban was associated with a similar risk of stroke/SE and a significantly lower risk of MB versus warfarin.

Anticoagulation Treatment and Outcomes of Venous Thromboembolism by Weight and Body Mass Index: Insights From the Veterans Health Administration

BACKGROUND

Consensus statements have recommended against the use of direct oral anticoagulants (DOACs) in venous thromboembolism (VTE) for patients ≥120 kg and ≥40 kg/m². We sought to determine use and outcomes of DOACs for VTE across weight and body mass index (BMI).

METHODS

We performed a retrospective cohort study of patients with first-time VTE 2013 to 2018 that were treated with DOAC or warfarin in the Veterans Health Administration. The Veterans Health Administration has implemented system-wide guidance for patient selection and shared decision-making for use of DOACs in VTE at extremes of weight. We stratified patients by weight and BMI and assessed (1) association of weight and BMI category to outcomes in those prescribed DOAC; and (2) association of DOAC, as compared to warfarin, to outcomes by weight and BMI categories. Outcomes of interest included major bleeding, clinically relevant nonmajor bleeding, and recurrent VTE.

RESULTS

The analysis cohort included 51 871 patients prescribed DOAC or warfarin within 30 days of index VTE diagnosis (age 64.5±13.1 years; 6.0% female; median weight 93.4 kg [25th-75th: 80.5-108.6 kg]). For patients ≥120 kg (N=6934 patients), 38.4% were treated with DOAC, as compared to 45.4% of those ≥60 to <100 kg (N=30 645; P<0.0001). DOAC prescription was not associated with major bleeds, clinically relevant nonmajor bleeds, or recurrent VTE for those in higher weight and BMI categories as compared to those in average weight and BMI categories. DOAC prescription, as compared to warfarin, was not associated with increased recurrent VTE in any weight or BMI category.

CONCLUSIONS

Patients ≥120 kg and ≥40 kg/m² with VTE are frequently prescribed DOAC by the Veterans Health Administration, without an increase in bleeding or recurrent VTE. These findings suggest DOACs can be safe and effective in this population and may argue for broader adoption of pharmacy policies that promote careful patient selection and shared decision making.

Estimation of risk of neuropsychiatric adverse events from varenicline, bupropion and nicotine patch versus placebo: secondary analysis of results from the EAGLES trial using Bayes factors

BACKGROUND AND AIMS

Analysed using classical frequentist hypothesis testing with alpha set to 0.05, the Evaluating Adverse Events in a Global Smoking Cessation Study (EAGLES) did not find enough evidence to reject the hypothesis of no difference in neuropsychiatric adverse events (NPSAEs) attributable to varenicline, bupropion, or nicotine patch compared with placebo. This might be because the null hypothesis was true or because the data were insensitive. The present study aimed to test the hypothesis more directly using Bayes factors.

DESIGN

EAGLES was a randomised, double-blind, triple-dummy, controlled trial.

SETTING

Global (16 countries across five continents), between November 2011 and January 2015.

PARTICIPANTS

Participants were smokers with (n = 4116) and without (n = 4028) psychiatric disorders.

INTERVENTIONS

Varenicline (1 mg twice daily), bupropion (150 mg twice daily), nicotine patch (21 mg once daily with taper) and matched placebos.

MEASUREMENTS

The outcomes included: (i) a composite measure of moderate/severe NPSAEs; and (ii) a composite measure of severe NPSAEs. The relative evidence for there being no difference in NPSAEs versus data insensitivity for the medications was calculated in the full and sub-samples using Bayes factors and corresponding robustness regions.

FINDINGS

For all but two comparisons, Bayes factors were <1/3, indicating moderate to strong evidence for no difference in risk of NPSAEs between active medications and placebo (Bayes factor = 0.02-0.23). In the psychiatric cohort versus placebo, the data were suggestive, but not conclusive of no increase in NPSAEs with varenicline (Bayes factor = 0.52) and bupropion (Bayes factor = 0.71). Here, the robustness regions ruled out a ≥7% and ≥8% risk increase with varenicline and bupropion, respectively.

CONCLUSIONS

Secondary analysis of the Evaluating Adverse Events in a Global Smoking Cessation Study trial using Bayes factors provides moderate to strong evidence that use of varenicline, bupropion or nicotine patches for smoking cessation does not increase the risk of neuropsychiatric adverse events relative to use of placebo in smokers without a history of psychiatric disorder. For smokers with a history of psychiatric disorder the evidence also points to no increased risk but with less confidence.

Efficacy and Safety of Pharmacotherapeutic Smoking Cessation Aids in Schizophrenia Spectrum Disorders: Subgroup Analysis of EAGLES

OBJECTIVE

This study aimed to evaluate the efficacy and safety of varenicline, bupropion, and nicotine replacement therapy (NRT) among smokers with schizophrenia spectrum disorders in post hoc analyses of Evaluating Adverse Events in a Global Smoking Cessation Study data.

METHODS

Smokers with schizophrenia spectrum disorder (N=390) and without a psychiatric illness (control group, N=4,028) were randomly assigned to receive varenicline, bupropion, NRT patch, or placebo for 12 weeks. Outcomes included abstinence rates during treatment and follow-up, number needed to treat (NNT) for abstinence, incidence of neuropsychiatric adverse events (NPSAEs), and temporal relationship between NPSAEs and abstinence status.

RESULTS

Smokers with schizophrenia smoked more and had greater dependence and fewer prior trials of cessation pharmacotherapy at baseline. At each time point, smokers with schizophrenia assigned to varenicline had significantly greater odds of abstinence compared with their matched placebo group, with NNT comparable to the control group. Bupropion and NRT increased odds of abstinence; confidence intervals (CIs) included 1 for some comparisons, and NNT for smokers with schizophrenia was greater than for the control group. No treatment was associated with significantly more NPSAEs, compared with placebo, in either cohort. The estimated NPSAE rate was 5% (95% CI=3.0-7.7) for smokers with schizophrenia and 1% (95% CI=0.6-2.1) for the control group. Over one-third of NPSAEs occurred during partial or full abstinence, suggesting a multifactorial nature.

CONCLUSIONS

For smokers with schizophrenia, varenicline led to significantly higher abstinence rates, and NNT was comparable to the control group. A significant proportion of NPSAEs occurred during early abstinence. No treatment significantly increased NPSAE prevalence.

Utilization of anticoagulants and predictors of treatment among hospitalized patients with atrial fibrillation in the USA

OBJECTIVE

To evaluate utilization of anticoagulants (ACs) and the predictors of treatment of patients with a diagnosis of atrial fibrillation (AF) during a hospital stay in the USA.

METHODS

Patients (≥18 years of age) who had a primary or secondary discharge diagnosis code of AF during a hospitalization (without a diagnosis of venous thromboembolism) were identified from the Premier Hospital database (1 January 2016-30 September 2017). AC treatments were examined during hospitalizations to assign AF patients into 3 study cohorts: those who received an oral AC (OAC), those who received parenteral AC only, and those who did not receive AC therapy. Multivariable logistic regression analyses were carried out to evaluate potential predictors of receiving parenteral AC only vs. OAC therapy, no AC therapy vs. OAC therapy, as well as the specific OAC drug choices.

RESULTS

Of the patients hospitalized with an AF diagnosis (n = 482,729; mean age: 74.7 years; 46.8% female; 82.9% White; 79.4% with Medicare), 42.6% received OAC therapy (most commonly, warfarin or apixaban), 35.3% parenteral AC only, and 22.2% no AC therapy. A key predictor of not receiving OAC therapy was having an AF diagnosis in the second position (applicable to 87.4% of study population). Greater comorbidity level and prior baseline bleeding were strong predictors of receiving parenteral AC only or not receiving any AC therapy vs. receiving OAC therapy. Predictors of receiving warfarin vs. apixaban included higher stroke risk and prior baseline bleeding.

LIMITATIONS

OAC utilization may have been underestimated since outpatient OAC utilization was not included in the analysis.

CONCLUSIONS

A substantial portion of hospitalized AF patients did not receive any AC therapy, particularly those patients with an AF diagnosis in the second position on hospital records. The predictors of inpatient AC treatment that were identified may be helpful in the clinical decision-making process for patients who are hospitalized with AF.

A review of global health technology assessments of non-VKA oral anticoagulants in non-valvular atrial fibrillation

BACKGROUND

This review assessed global health technology assessment (HTA) reports and recommendations of non-vitamin K oral anticoagulants (NOACs) in non-valvular atrial fibrillation (NVAF).

METHODS

NHTA agency websites were searched for HTA reports evaluating NOACs versus NOACs or vitamin K antagonists. HTA methods and information on patient involvement/access were collected and empirically analyzed.

RESULTS

The review identified 38 unique HTA reports published between 2012 and 2017 in 16 countries including 11 in Europe. NOACs that were cost-effective per local willingness-to-pay (WTP) thresholds were positively recommended for the treatment of NVAF. WTP thresholds ranged from €20,000 to 69,000. Apixaban was recommended in 10/12 (83%) countries, dabigatran in 9/13 (69%) countries, and rivaroxaban in 10/13 (76%) over warfarin. Edoxaban was recommended in 5/7 (71%) countries. Economic evaluations and recommendations comparing NOACs were sparse (two or three countries per NOAC) and generally favored apixaban and edoxaban, followed by dabigatran. Eleven HTA reports from four countries considered the patient voice (Canada [n = 3], Scotland [n = 3], England [n = 4], Brazil [n = 1]); however, only 2/11 (18%) developed recommendations based on this. Among the reports with a positive recommendation, 26/30 (87%) featured a decision that aligned with the approved regulatory label.

CONCLUSIONS

Most agencies recommended NOACs over warfarin for patients with NVAF. Few countries made statements recommending one NOAC over another. Given different WTP thresholds, a drug that is cost-effective in one market may not be in another. Therefore, the various NOAC recommendations from HTA agencies cannot be generalized across different countries.

Comparative Clinical and Economic Outcomes Associated with Warfarin Versus Apixaban in the Treatment of Patients with Venous Thromboembolism in a Large U.S. Commercial Claims Database

BACKGROUND

Venous thromboembolism (VTE), constituting deep vein thrombosis (DVT) and pulmonary embolism (PE), is a common cause of vascular-related morbidity and mortality, resulting in a significant clinical and economic burden in the United States each year. Clinical guidelines recommend that patients with DVT and PE without cancer should be initiated on anticoagulation therapy with a direct oral anticoagulant over a vitamin K antagonist. Yet there is limited real-world evidence comparing the economic burden of warfarin and apixaban in treating VTE patients in a large commercially insured population.

OBJECTIVE

To compare safety and effectiveness of warfarin and apixaban and evaluate associated economic burden in treating VTE patients in a large U.S. commercial health care claims database.

METHODS

The PharMetrics Plus database was used to identify oral anticoagulant (OAC)-naive patients aged ≥ 18 years who initiated apixaban or warfarin within 30 days of a qualifying VTE encounter and had continuous health plan enrollment with medical and pharmacy benefits for 6 months before treatment initiation. Apixaban initiators and warfarin initiators were matched using the propensity score matching (PSM) technique. Cox proportional hazard models were used to assess and compare the risk of major bleeding (MB), clinically relevant nonmajor (CRNM) bleeding, and recurrent VTE. Generalized linear models were used to assess and compare the all-cause health care costs. A 2-part model with bootstrapping was used to evaluate MB- and recurrent VTE-related medical costs.

RESULTS

Among 25,193 prematched patients, 13,421 (53.3%) were prescribed warfarin and 11,772 (46.7%) were prescribed apixaban. After 1:1 PSM, 8,858 matched warfarin-apixaban pairs were selected with a mean follow-up of 109 days and 103 days, respectively. Warfarin was associated with a significantly higher risk of MB (HR = 1.52, 95% CI = 1.14-2.04), CRNM bleeding (HR = 1.27, 95% CI = 1017.15-1.40), and recurrent VTE (HR = 1.50, 95% CI = 1.24-1.82) compared with apixaban. Warfarin patients had significantly higher all-cause medical costs per patient per month (PPPM; $2,333 vs. $1,992; P = 0.001), MB-related costs PPPM ($112 vs. $65; P = 0.020), and recurrent VTE-related costs PPPM ($287 vs. $206; P = 0.014) compared with apixaban patients. Warfarin patients had similar all-cause total health care costs PPPM ($2,630 vs. $2,420; P = 0.051) compared with apixaban patients.

CONCLUSIONS

Warfarin use was associated with a higher risk of MB, CRNM bleeding, and recurrent VTE compared with apixaban. Warfarin use was also associated with higher all-cause medical costs, MB-related medical costs, and recurrent VTE-related costs PPPM compared with apixaban. DISCLOSURES: This study was funded by Bristol Myers Squibb and Pfizer, which were also involved in the study design, as well as writing and revising of the manuscript. Guo, Rajpura, Okano, and Rosenblatt are employees of Bristol Myers Squibb. Hlavacek, Mardekian, and Russ are employees of Pfizer. Keshishian, Sah, Delinger, and Mu are employees of SIMR, LLC, which received funding from the study sponsors to conduct this study.

Clinical characteristics and treatment patterns of patients with venous thromboembolism (VTE) transitioning from hospital to post-discharge settings

OBJECTIVE

This study examined anticoagulant use during and after a hospital encounter for venous thromboembolism (VTE), a transition of care largely uncharacterized in the literature.

METHODS

Adults with a VTE diagnosis code during a hospital encounter (emergency department [ED], observation area [OBS], or inpatient hospital [IP]) from January 2012 to August 2017 were identified in an electronic health records database. The first such hospital encounter was defined as the index VTE encounter. Patients were linked to a claims database and required to be continuously enrolled for six months before the index admission date through six months after the index discharge date. Anticoagulants administered during the index VTE encounter and filled on or within 30 days of discharge were summarized descriptively overall, and by the type of index VTE encounter (IP, No IP) and anticoagulants administered during the index VTE encounter.

RESULTS

Among 2,968 eligible patients, mean (SD) age was 64 (16) years, 51% were female, 67% had an IP index VTE encounter, and 77% received anticoagulation therapy during the index VTE encounter. In total, 60% filled a prescription order for anticoagulant within 30 days post-discharge. Of those who received a direct oral anticoagulant (DOAC), warfarin, or parenteral anticoagulant only during the index VTE encounter, 74%, 69%, and 34%, respectively, filled a prescription for the same anticoagulant post-discharge. Patients treated with a DOAC or warfarin during an ED or OBS VTE encounter without a subsequent inpatient hospitalization were more likely to remain on the same anticoagulation therapy post-discharge than those with an inpatient hospitalization (81% vs 69% for DOAC and 75% vs 68% for warfarin).

CONCLUSIONS

Many patients treated with anticoagulation therapy during a VTE hospital encounter did not fill a prescription for an anticoagulant within 30 days post-discharge, highlighting an opportunity for improved management of care transitions in this patient population.

Comparison of readmissions among hospitalized nonvalvular atrial fibrillation patients treated with oral anticoagulants in the United States

Objectives

To compare the risks of 1-month all-cause, major bleeding (MB)-related and stroke-related readmissions and the associated hospital resource use and costs among patients previously hospitalized for nonvalvular atrial fibrillation (NVAF) and treated with warfarin, rivaroxaban, and dabigatran vs apixaban.

Methods

Adult patients hospitalized with NVAF (any discharge diagnosis position) who received apixaban, warfarin, rivaroxaban, or dabigatran during hospitalization were identified from the Premier database (1 January 2013–30 June 2017) and grouped into respective cohorts. Propensity score matching was used to generate cohorts with similar characteristics. In regression analyses the risk of readmissions that occurred within 1 month of discharge were evaluated and the associated length of stay (LOS) and costs compared.

Results

NVAF patients treated with warfarin vs apixaban had significantly greater risk of all-cause (odds ratio [OR] = 1.05; confidence interval [CI] = 1.02–1.08; p < .001), MB-related (OR: 1.28; CI: 1.16–1.42; p < .001), and stroke-related (OR: 1.33; CI: 1.11–1.58; p = .002) readmissions; for all readmission categories, average LOS was significantly longer and costs significantly higher for warfarin treated patients. NVAF patients treated with rivaroxaban versus apixaban had significantly greater risk of all-cause (OR: 1.06; CI: 1.02–1.09; p = .001) and MB-related (OR = 1.62; CI = 1.44–1.83; p < .001) readmissions, but not stroke-related readmission; for MB-related readmissions average LOS and costs were higher for rivaroxaban treated patients. Significant differences in risks of all-cause, MB-related, and stroke-related readmissions were not observed between the apixaban and dabigatran cohorts.

Conclusion

In this retrospective real-world analysis of NVAF patients, apixaban treatment was associated with better clinical outcomes than warfarin or rivaroxaban and lower hospital resource burden.

Varenicline: mode of action, efficacy, safety and accumulated experience salient for clinical populations

Objective: Varenicline, a selective partial agonist of the α4β2 nicotinic acetylcholine receptor, is a smoking cessation pharmacotherapy that more than doubles the chance of quitting smoking at 6 months compared with placebo. This article reviews salient knowledge of the discovery, pharmacological characteristics, and the efficacy and safety of varenicline in general and in specific populations of smokers and provides recommendations to support use in clinical practice.Methods: Literature searches for varenicline were conducted using PubMed, with date limitations of 2000-2018 inclusive, using search terms covering the discovery, mechanism of action, pharmacokinetics, efficacy and safety in different populations of smokers, alternative quit approaches and combination therapy. Selection of safety and efficacy data was limited to clinical trials, meta-analyses and observational studies.Results: Standard administration of varenicline is efficacious in helping smokers to quit, including smokers with cardiovascular disease and chronic obstructive pulmonary disease. Furthermore, varenicline efficacy may be improved with pre-loading, a gradual quitting approach for smokers unwilling or unable to quit abruptly, and extended treatment in smokers who have recently quit to help maintain abstinence. Initial concerns regarding the association of varenicline with increased risk of neuropsychiatric and cardiovascular adverse events have been disproven after extensive clinical evaluations, and the benefit-risk profile of varenicline is considered favorable.Conclusions: Varenicline is efficacious and safe for all adult smokers with a range of clinical characteristics. Evidence suggests that approaches offering greater flexibility in timing and duration of treatment may further extend treatment efficacy and clinical reach.

Efficacy and safety of pharmacotherapies for smoking cessation in anxiety disorders: Subgroup analysis of the randomized, active- and placebo-controlled EAGLES trial

BACKGROUND

Smoking rates are high in adults with anxiety disorders (ADs), yet little is known about the safety and efficacy of smoking-cessation pharmacotherapies in this group.

METHODS

Post hoc analyses in 712 smokers with AD (posttraumatic stress disorder [PTSD], n = 192; generalized anxiety disorder [GAD], n = 243; panic disorder [PD], n = 277) and in a nonpsychiatric cohort (NPC; n = 4,028). Participants were randomly assigned to varenicline, bupropion, nicotine-replacement therapy (NRT), or placebo plus weekly smoking-cessation counseling for 12 weeks, with 12 weeks follow-up. General linear models were used to test the effects of treatment group, cohort, and their interaction on neuropsychiatric adverse events (NPSAEs), and continuous abstinence weeks 9-12 (treatment) and 9-24 (follow-up).

RESULTS

NPSAE incidence for PTSD (6.9%), GAD (5.4%), and PD (6.2%) was higher versus NPC (2.1%), regardless of treatment. Across all treatments, smokers with PTSD (odds ratio [OR] = 0.58), GAD (OR = 0.72), and PD (OR = 0.53) had lower continuous abstinence rates weeks 9-12 (CAR9-12) versus NPC. Varenicline demonstrated superior efficacy to placebo in smokers with GAD and PD, respectively (OR = 4.53; 95% confidence interval [CI] = 1.20-17.10; and OR = 8.49; 95% CI = 1.57-45.78); NRT was superior to placebo in smokers with PD (OR = 7.42; 95% CI = 1.37-40.35). While there was no statistically significant effect of any treatment on CAR9-12 for smokers with PTSD, varenicline improved 7-day point prevalence abstinence at end of treatment in this subcohort.

CONCLUSION

Individuals with ADs were more likely than those without psychiatric illness to experience moderate to severe NPSAEs during smoking-cessation attempts, regardless of treatment. While the study was not powered to evaluate abstinence outcomes with these subgroups of smokers with ADs, varenicline provided significant benefit for cessation in those with GAD and PD, while NRT provided significant benefit for those with PD.

Comparison of inpatient admission rates of patients treated with apixaban vs. warfarin for venous thromboembolism in the emergency department

Objectives: This study evaluated inpatient admission status, hospitalization length of stay (LOS), hospital costs, and readmissions of patients who were diagnosed with venous thromboembolism (VTE) and treated with apixaban or warfarin in the emergency department (ED).Methods: Patients (≥18 years) with an ED visit with a primary discharge diagnosis code of VTE were identified from the Premier Hospital database (8/1/2014-5/31/2018). Patients who received apixaban or warfarin during the ED visit were selected and grouped into two treatment cohorts. Outcomes of ED disposition (discharged or admitted to the inpatient setting), hospital LOS, hospital cost of index event, and rate of 1-month readmissions were compared for the study cohorts.Results: Of the overall study population, 30.5% (n = 12,174; mean age: 59.7 years) received apixaban and 69.5% (n = 27,767; mean age: 59.3 years) received warfarin for VTE in the ED. After adjusting for patient and hospital characteristics, the regression analysis showed that apixaban was associated with a significantly lower likelihood of admission to the inpatient setting vs. warfarin (Odds Ratio [OR]: 0.12, 95% Confidence Interval [CI]: 0.12 to 0.13; p < 0.001). Correspondingly, mean index hospital LOS was 1.42 days shorter (95% CI: -1.47 to -1.36; p < 0.001) and mean index event hospital cost per patient was significantly lower by $4,276 ($3,732 [95% CI: $3,565 to $3,907] vs. $8,008 [95% CI: $7,676 to $8,355]; p < 0.001). Also, the likelihood of all-cause 1-month readmission was significantly lower for patients treated with apixaban vs. warfarin (OR: 0.85, 95% CI: 0.79 to 0.92; p < 0.001).Conclusions: In the real-world setting, VTE patients with an ED visit who were treated with apixaban vs. warfarin had a lower likelihood of being admitted to the inpatient setting, which was reflected in shorter average LOS and lower average index event cost. Additionally, the risk of 1-month readmission was also lower for patients treated with apixaban vs. warfarin.

Safety, effectiveness, and health care cost comparisons among elderly patients with venous thromboembolism prescribed warfarin or apixaban in the United States Medicare population

Objective: To compare safety, effectiveness, and healthcare costs of major bleeding (MB), clinically relevant non-major (CRNM) bleeding, recurrent venous thromboembolism (VTE), and all-cause hospitalization among elderly Medicare VTE patients prescribed warfarin vs apixaban.Methods: Using 100% Medicare data, elderly patients prescribed apixaban or warfarin within 30 days after a VTE encounter were identified. Patients had continuous health plan enrollment and no parenteral or oral anticoagulant use ≤6 months preceding the VTE encounter. Cohorts were balanced using 1:1 propensity score matching (PSM). Cox proportional hazard models were used to assess the risk of MB, CRNM bleeding, recurrent VTE, and all-cause hospitalization. Generalized linear and two-part models were used to estimate MB-, recurrent VTE-, and all-cause related costs (per patient per month [PPPM]).Results: In the pre-matched cohort, 25,284 (66.9%) patients were prescribed warfarin and 12,515 (33.1%) apixaban. After 1:1 PSM, 11,363 matched pairs of apixaban-warfarin patients were included for a mean follow-up of 4.0 and 4.4 months, respectively. Matched cohorts had a mean age of 78 years and mean Charlson Comorbidity Index score of 2.9. Warfarin was associated with a higher risk of MB (hazard ratio [HR] = 1.31; 95% confidence interval [CI] = 1.10-1.57) and CRNM bleeding (HR = 1.31; 95% CI = 1.19-1.43) vs apixaban. The risks of recurrent VTE (HR = 0.96; 95% CI = 0.70-1.33) and all-cause hospitalization (HR = 1.05; 95% CI = 0.99-1.12) were similar among warfarin and apixaban patients. Warfarin patients had higher MB-related ($147 vs $75; p = .003) and all-cause costs PPPM ($3,267 vs $3,033; p < .001), but similar recurrent VTE-related medical costs PPPM ($30 vs $36; p = .516) vs apixaban patients.Conclusions: Warfarin was associated with significantly higher risk of MB and CRNM bleeding as well as higher MB-related and all-cause costs vs apixaban patients. Recurrent VTE risk and costs were similar among warfarin and apixaban patients.

Continuation with apixaban treatment is associated with lower risk for hospitalization and medical costs among elderly patients

Objective: To compare the risk of hospitalization and costs associated with major bleeding (MB) or stroke/systemic embolism (SE) among elderly patients with nonvalvular atrial fibrillation (NVAF) who initiated apixaban then switched to another oral anticoagulant (OAC) vs. those who continued with apixaban treatment. Methods: NVAF patients (≥65 years) initiating apixaban were identified from the Humana database (1 January 2013-30 September 2017) and grouped into switcher and continuer cohorts. For switchers, the earliest switch from apixaban to another OAC was defined as the index event/date. A random date during apixaban treatment was selected as the index date for continuers. Patients were followed from index date to health plan disenrollment or 31 December 2017, whichever was earlier. Multivariable regression analyses were used to examine the association of switchers vs. continuers with risk of MB-related or stroke/SE-related hospitalization and healthcare costs during follow-up. Results: Of 7858 elderly NVAF patients included in the study, 14% (N = 1110; mean age: 78 years) were switchers; 86% (N = 6748; mean age: 79 years) were continuers. Apixaban switchers vs. continuers had significantly greater risk of MB-related hospitalization (hazard ratio [HR]: 2.00; 95% CI: 1.52-2.64; p < .001) during follow-up; risk of stroke/SE hospitalization did not differ significantly (HR: 1.36, 95% CI: 0.89-2.06, p = .154). MB- and stroke/SE-related medical costs were higher for switchers vs. continuers, although total all-cause healthcare costs were similar. Conclusion: Elderly patients with NVAF in the US who continued with apixaban treatment had a lower risk of MB-related hospitalization and lower MB- and stroke/SE-related medical costs compared to patients who switched to another OAC.

Safety and efficacy of first-line smoking cessation pharmacotherapies in bipolar disorders: Subgroup analysis of a randomized clinical trial

OBJECTIVES

Post hoc analyses of EAGLES data to examine safety and efficacy of first-line smoking cessation pharmacotherapies in smokers with bipolar disorders (BD).

METHODS

Smokers with BD I/II (n = 285; 81.4% with BD I) and a comparison nonpsychiatric cohort (NPC; n = 2794) were randomly assigned to varenicline, bupropion, nicotine replacement therapy (NRT), or placebo for 12 weeks, plus weekly counseling. Primary outcomes were occurrence of moderate to severe neuropsychiatric adverse events (NPSAEs) and Weeks 9-12 biochemically-confirmed continuous abstinence (CA) rates.

RESULTS

For BD smokers, NPSAE risk differences versus placebo were: varenicline, 6.17 (95% CI: -7.84 to 20.18); bupropion, 4.09 (-8.82 to 16.99); NRT, -0.56 (-12.34 to 11.22). ORs for Weeks 9-12 CA, comparing active medication to placebo among BD smokers were: varenicline, 2.61 (0.68-9.95); bupropion, 1.29 (0.31-5.37), NRT, 0.71 (0.14-3.74). Pooling across treatments, NPSAE occurrence was higher (10.7% versus 2.3%; P < 0.001) and CA rates were lower (22.8% versus 13.3%; P = 0.008) in BD than NPC.

LIMITATIONS

Study not powered to detect differences in safety and efficacy in the BD subcohort; generalizability limited to stably treated BD without current substance use disorders.

CONCLUSIONS

Smokers with BD had higher risk of NPSAEs and were less likely to quit overall than NPC smokers. Among smokers with BD, NPSAE risk difference estimates for active treatments versus placebo ranged from 1% lower to 6% higher. Efficacy of varenicline in smokers with BD was similar to EAGLES main outcomes; bupropion and NRT effect sizes were descriptively lower. Varenicline may be a tolerable and effective cessation treatment for smokers with BD.

TRIAL REGISTRATION

ClinicalTrials.gov identifier (https://clinicaltrials.gov/): NCT01456936.

Switching to Another Oral Anticoagulant and Drug Discontinuation Among Elderly Patients With Nonvalvular Atrial Fibrillation Treated With Different Direct Oral Anticoagulants

We compared the risks of switching to another oral anticoagulant (OAC) and discontinuation of direct oral anticoagulants (DOACs) among elderly patients with nonvalvular atrial fibrillation (NVAF) who were prescribed rivaroxaban or dabigatran versus apixaban. Patients (≥65 years of age) with NVAF prescribed DOACs (January 1, 2013 to September 30, 2017) were identified from the Humana research database and grouped into DOAC cohorts. Cox regression analyses were used to evaluate whether the risk for switching to another OAC or discontinuing index DOACs differed among cohorts. Of the study population (N = 38 250), 55.9% were prescribed apixaban (mean age: 78.6 years; 49.8% female), 37.3% rivaroxaban (mean age: 77.4 years; 46.7% female), and 6.8% dabigatran (mean age: 77.0 years; 44.0% female). Compared to patients prescribed apixaban, patients prescribed rivaroxaban (hazard ratio [HR]: 2.08; 95% confidence interval [CI], 1.92-2.25; P < .001) or dabigatran (HR: 3.74; 95% CI, 3.35-4.18, P < .001) had a significantly higher risk of switching to another OAC during the follow-up; compared to patients prescribed apixaban, the risks of discontinuation were also higher for patients treated with rivaroxaban (HR: 1.10; 95% CI, 1.07-1.13, P < .001) or dabigatran (HR: 1.29; 95% CI, 1.23-1.35, P < .001).

Predictors of Neuropsychiatric Adverse Events with Smoking Cessation Medications in the Randomized Controlled EAGLES Trial

BACKGROUND

Pre-treatment factors that increase smokers' risk of experiencing neuropsychiatric adverse events (NPSAEs) when quitting smoking are unknown.

OBJECTIVE

To identify baseline smoker characteristics beyond the history of mental illness that predict which participants were more likely to experience moderate to severe NPSAEs in EAGLES.

DESIGN

A prospective correlational cohort study in the context of a multinational, multicenter, double-blind, randomized trial.

PARTICIPANTS

Smokers without (N = 3984; NPC)/with (N = 4050; PC) histories of, or current clinically stable, psychiatric disorders including mood (N = 2882; 71%), anxiety (N = 782; 19%), and psychotic (N = 386; 10%) disorders.

INTERVENTIONS

Bupropion, 150 mg twice daily, or varenicline, 1 mg twice daily, versus active control (nicotine patch, 21 mg/day with taper) and placebo for 12 weeks with 12-week non-treatment follow-up.

MAIN MEASURES

Primary safety outcome was the incidence of a composite measure of moderate/severe NPSAEs. Associations among baseline demographic/clinical characteristics and the primary safety endpoint were analyzed post hoc via generalized linear regression.

KEY RESULTS

The incidence of moderate to severe NPSAEs was higher among smokers in the PC (238/4050; 5.9%) than in the NPC (84/3984; 2.1%). Three baseline characteristics predicted increased risk for experiencing clinically significant NPSAEs when quitting regardless of carrying a psychiatric diagnosis: current symptoms of anxiety (for every ~ 4-unit increase in HADS anxiety score, the absolute risk of occurrence of the NPSAE endpoint increased by 1% in both PC and NPC); prior history of suicidal ideation and/or behavior (PC, 4.4% increase; P = 0.001; NPC, 4.1% increase; P = 0.02), and being of White race (versus Black: PC, 2.9% ± 0.9 [SE] increase; P = 0.002; and NPC, 3.4% ± 0.8 [SE] increase; P = 0.001). Among smokers with psychiatric disorders, younger age, female sex, history of substance use disorders, and proxy measures of nicotine dependence or psychiatric illness severity also predicted greater risk. There were no significant interactions between these characteristics and treatment. Smokers with unstable psychiatric disorders or with current, active substance abuse were excluded from the study.

CONCLUSIONS

Irrespective of cessation pharmacotherapy use, smokers attempting to quit were more likely to experience moderate to severe NPSAEs if they reported current anxiety or prior suicidal ideation at baseline and were White. In smokers with a psychiatric history, female sex, younger age, and greater severity of nicotine dependence were also predictive.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01456936.

Abstract 110: Clinical Characteristics and Anticoagulant Transition Patterns of Hospitalized Patients with Venous Thromboembolism: A Retrospective Analysis Using Electronic Health Record Data

Objective: Describe the clinical characteristics and anticoagulant use of patients with venous thromboembolism (VTE) transitioning from a hospital setting using an electronic health care (EHR) database.

Methods: This retrospective EHR study analyzed adults (18+ years) with a VTE diagnosis code during a hospital encounter (emergency department [ED], observation [OBS] area, or inpatient [IP] stay) between 1/1/2012-8/31/2017 (ID period). The first VTE hospital encounter (from admission to discharge) during the ID period was defined as the index VTE encounter. Patients with evidence of atrial fibrillation/flutter, pregnancy, or multiple oral anticoagulants during the index VTE encounter were excluded. Clinical characteristics and anticoagulants administered during the index VTE encounter and ordered on the discharge date were reported descriptively.

Results: Among the 282,978 patients identified, the mean age (SD) age was 61 (17) years; 48% (136,155 of 282,978) were male; 78% (221,120 of 282,978) were Caucasian; 59% (167,628 of 282,978) had deep vein thrombosis without a pulmonary embolism; 18% (49,596 of 282,978) had evidence of cancer; and 7% (19,447 of 282,978) had evidence of a provoked etiology (hormonal therapy, lower extremity fracture/trauma, pelvic/orthopedic surgery) during the index VTE encounter. Nearly three-quarters (199,568 of 282,978) were admitted for an IP stay with a median length of stay of 6 days; the remaining 29% (83,410 of 282,978) were treated in an ED or OBS area only. Overall, 73% (207,640 of 282,978) were discharged home, 19% (54,283 of 282,978) were discharged to another IP facility, and 7% (21,055 of 282,978) had other or unknown discharge status. During the index VTE encounter, 67% (188,271 of 282,978) received heparin (low molecular weight or unfractionated), 34% (95,090 of 282,978) received warfarin, 12% (34,540 of 282,978) received a non-vitamin K oral anticoagulant (DOAC), and 27% (76,877 of 282,978) had no record of anticoagulant administration. Of those with heparin, 41% (76,471 of 188,271) received heparin only. More than half of those with an order for a DOAC or warfarin on the discharge date had received the same anticoagulant during the index VTE encounter, namely, 65% (22,344 of 34,540) with a DOAC during the index VTE encounter received a discharge order for a DOAC and 58% (55,369 of 95,090) with warfarin during the index VTE encounter received a discharge order for warfarin. Among those with heparin only during the index VTE encounter, approximately 18% (13,759 of 76,471) received an order for heparin, 6% (4,217 of 76,471) received an order for a DOAC, and 5% (3,810 of 76,471) received an order for warfarin on discharge.

Conclusion: This EHR study observed that a sizable proportion of hospitalized patients with VTE were either prescribed a different anticoagulant on discharge or discharged without an anticoagulant prescription.

Abstract 138: Effectiveness and Safety of Apixaban Compared to Warfarin among Venous Thromboembolism Patients in the United States Medicare Population

Background: The AMPLIFY randomized clinical trial showed that apixaban was associated with significantly lower major bleeding (MB) compared to warfarin for patients with venous thromboembolism (VTE). The main objective of this study was to compare the risk of major bleeding (MB), clinically relevant non-major bleeding (CRNM), and recurrent VTE among VTE patients treated with apixaban vs warfarin in the US Medicare population.

Methods: Patients (aged ≥65 years) prescribed apixaban or warfarin within 30 days following a VTE event diagnosed in hospital or ambulatory setting were identified from 01SEPT2014-31DEC2016 using 100% CMS Medicare data. The first apixaban or warfarin prescription claim outside of the hospital was defined as the index date. Patients were required to have had continuous health plan enrollment for 6 months and no parenteral or oral anticoagulant use before the index VTE event. Outcomes were assessed from index date to the earliest of discontinuation, switch, health plan disenrollment, death, 6 months post-index date, or 31DEC2016. One-to-one propensity score matching (PSM) was used to balance patient characteristics. Cox proportional hazard models were used to estimate the risk of MB, CRNM bleeding, and recurrent VTE.

Results: Among 37,799 patients meeting inclusion criteria, 25,284 patients initiated warfarin (66.9%) and 12,515 patients initiated apixaban (33.1%). Post-PSM, 11,363 matched pairs of apixaban-warfarin patients were identified, with a mean follow-up period of 4.0 and 4.4 months. Mean age was 78 years; nearly 37% of patients were male with a mean Charlson Comorbidity Index score of 2.9 in both groups. Apixaban was associated with a lower risk of MB (HR: 0.76; 95% CI: 0.64-0.91) and CRNM bleeding (HR: 0.77; 95% CI: 0.70-0.84) compared to warfarin. The risk of recurrent VTE was similar among apixaban and warfarin patients (HR: 1.04; 95% CI: 0.75-1.43; Figure).

Conclusions: Among US Medicare patients with VTE, apixaban was associated with a lower risk of MB and CRNM bleeding and similar risk of recurrent VTE compared to warfarin. These results may be supportive in evaluating the risk-benefit ratio of apixaban for treatment of elderly VTE patients.

Abstract 210: Rates of Drug Switching and Discontinuation among Nonvalvular Atrial Fibrillation Elderly Patients Treated with Direct Oral Anticoagulants in the US

Background: While many studies have demonstrated the efficacy of direct-acting oral anticoagulants (DOACs) for stroke risk reduction among nonvalvular atrial fibrillation (NVAF) patients, there is little information regarding drug switching and discontinuation patterns in real-world settings, particularly in older adults. Thus, we evaluated rates of switching and discontinuation among elderly NVAF patients who initiated any of the three most commonly prescribed DOACs in the US.

Methods: Patients ≥65 years who initiated apixaban, rivaroxaban or dabigatran (index event/date) were identified from the Humana database (1/1/2013-9/30/2017) and grouped into cohorts by index DOAC. Patients were required to have an NVAF diagnosis and continuous health plan enrollment for ≥12 months prior to the index date and ≥3 months during the follow-up period after the index date. Percentages of patients in each study cohort who switched to any other DOAC or warfarin or discontinued their index DOAC were evaluated. Multivariable Cox regression analyses were carried out to evaluate the impact of index DOAC treatments on the likelihood of switching or discontinuation while controlling for differences in patient characteristics.

Results: Of the final study population (n=38,250), 56% initiated apixaban (n=21,376; mean age: 78.6 years), 37% rivaroxaban (n=14,277; mean age: 77.4 years), and 7% dabigatran (n=2,597; mean age: 77.0 years). During follow-up, the switching rate was lowest for patients treated with apixaban at 5.2%, followed by patients treated with rivaroxaban (10.6%), and patients treated with dabigatran (16.9%, p<0.001 across the 3 cohorts). Patients treated with apixaban also had the lowest discontinuation rate (63.2% vs. 68.7% vs. 71.7%, p<0.001). After controlling for patient differences, those treated with rivaroxaban and dabigatran had significantly greater likelihood of switching treatment than patients treated with apixaban (Figure A). Also, rivaroxaban and dabigatran treated patients were significantly more likely to discontinue DOAC treatment (Figure B).

Conclusion: Of the DOACs evaluated in this real-world study, apixaban was associated with the lowest rates of switching and discontinuation among elderly NVAF patients.

Factors associated with the efficacy of smoking cessation treatments and predictors of smoking abstinence in EAGLES

AIMS

To assess (1) how far the efficacies of front-line smoking cessation pharmacotherapies vary as a function of smoker characteristics and (2) associations between these characteristics and success of smoking cessation attempts.

DESIGN

Prospective correlational study in the context of a double-blind randomized trial. The outcome was regressed individually onto each covariate after adjusting for treatment, and then a forward stepwise model constructed. Treatment moderator effects of covariates were tested by treatment × covariate interactions.

SETTING

Health service facilities in multiple countries.

PARTICIPANTS

Data came from 8120 smokers willing to make a quit attempt, randomized to varenicline, bupropion, nicotine replacement therapy (NRT) or placebo in Evaluating Adverse Events in a Global Smoking Cessation Study (EAGLES) between 30 November 2011 and 13 January 2015.

MEASUREMENTS

Smoker characteristics measured at baseline were country, psychiatric history, sex, age, body mass index (BMI), ethnic group, life-time suicidal ideation/behaviour, anxiety, depression, aggression, psychotropic medication, history of alcohol/substance use disorder, age of starting smoking, cigarette dependence [Fagerström Test for Cigarette Dependence (FTCD)] and prior use of study medicines. Outcome was biochemically confirmed continuous abstinence at weeks 9-24 from start of treatment.

FINDINGS

No statistically significant treatment × covariate interactions were found. Odds of success were associated independently positively with age [odds ratio (OR) = 1.01; 95% confidence interval (CI) = 1.00, 1.01], BMI (1.01; 95% CI = 1.00, 1.02) and age of starting smoking (1.03; 95% CI = 1.02, 1.04). Odds were associated independently negatively with US (versus non-US) study site (0.53; 95% CI = 0.46, 0.61), black (versus white) ethnic group (0.57; 95% CI = 0.45, 0.72), mood disorder (0.85; 95% CI = 0.73, 0.99), anxiety disorder (0.71; 95% CI = 0.55, 0.90) and psychotic disorder (0.73; 95% CI = 0.50, 1.07), taking psychotropic medication (0.81; 95% CI = 0.68, 0.95), FTCD (0.89; 95% CI = 0.87, 0.92) and previous use of NRT (0.78; 95% CI = 0.67, 0.91).

CONCLUSIONS

While a range of smoker characteristics-including psychiatric history, cigarette dependence and prior use of nicotine replacement therapy (NRT)-are associated with lower cessation rates, they do not substantially influence the efficacy of varenicline, bupropion or NRT.

Neuropsychiatric safety and efficacy of varenicline, bupropion, and nicotine patch in smokers with and without psychiatric disorders (EAGLES): a double-blind, randomised, placebo-controlled clinical trial

BACKGROUND

Substantial concerns have been raised about the neuropsychiatric safety of the smoking cessation medications varenicline and bupropion. Their efficacy relative to nicotine patch largely relies on indirect comparisons, and there is limited information on safety and efficacy in smokers with psychiatric disorders. We compared the relative neuropsychiatric safety risk and efficacy of varenicline and bupropion with nicotine patch and placebo in smokers with and without psychiatric disorders.

METHODS

We did a randomised, double-blind, triple-dummy, placebo-controlled and active-controlled (nicotine patch; 21 mg per day with taper) trial of varenicline (1 mg twice a day) and bupropion (150 mg twice a day) for 12 weeks with 12-week non-treatment follow-up done at 140 centres (clinical trial centres, academic centres, and outpatient clinics) in 16 countries between Nov 30, 2011, and Jan 13, 2015. Participants were motivated-to-quit smokers with and without psychiatric disorders who received brief cessation counselling at each visit. Randomisation was computer generated (1:1:1:1 ratio). Participants, investigators, and research personnel were masked to treatment assignments. The primary endpoint was the incidence of a composite measure of moderate and severe neuropsychiatric adverse events. The main efficacy endpoint was biochemically confirmed continuous abstinence for weeks 9-12. All participants randomly assigned were included in the efficacy analysis and those who received treatment were included in the safety analysis. The trial is registered at ClinicalTrials.gov (number NCT01456936) and is now closed.

FINDINGS

8144 participants were randomly assigned, 4116 to the psychiatric cohort (4074 included in the safety analysis) and 4028 to the non-psychiatric cohort (3984 included in the safety analysis). In the non-psychiatric cohort, 13 (1·3%) of 990 participants reported moderate and severe neuropsychiatric adverse events in the varenicline group, 22 (2·2%) of 989 in the bupropion group, 25 (2·5%) of 1006 in the nicotine patch group, and 24 (2·4%) of 999 in the placebo group. The varenicline-placebo and bupropion-placebo risk differences (RDs) for moderate and severe neuropsychiatric adverse events were -1·28 (95% CI -2·40 to -0·15) and -0·08 (-1·37 to 1·21), respectively; the RDs for comparisons with nicotine patch were -1·07 (-2·21 to 0·08) and 0·13 (-1·19 to 1·45), respectively. In the psychiatric cohort, moderate and severe neuropsychiatric adverse events were reported in 67 (6·5%) of 1026 participants in the varenicline group, 68 (6·7%) of 1017 in the bupropion group, 53 (5·2%) of 1016 in the nicotine patch group, and 50 (4·9%) of 1015 in the placebo group. The varenicline-placebo and bupropion-placebo RDs were 1·59 (95% CI -0·42 to 3·59) and 1·78 (-0·24 to 3·81), respectively; the RDs versus nicotine patch were 1·22 (-0·81 to 3·25) and 1·42 (-0·63 to 3·46), respectively. Varenicline-treated participants achieved higher abstinence rates than those on placebo (odds ratio [OR] 3·61, 95% CI 3·07 to 4·24), nicotine patch (1·68, 1·46 to 1·93), and bupropion (1·75, 1·52 to 2·01). Those on bupropion and nicotine patch achieved higher abstinence rates than those on placebo (OR 2·07 [1·75 to 2·45] and 2·15 [1·82 to 2·54], respectively). Across cohorts, the most frequent adverse events by treatment group were nausea (varenicline, 25% [511 of 2016 participants]), insomnia (bupropion, 12% [245 of 2006 participants]), abnormal dreams (nicotine patch, 12% [251 of 2022 participants]), and headache (placebo, 10% [199 of 2014 participants]). Efficacy treatment comparison did not differ by cohort.

INTERPRETATION

The study did not show a significant increase in neuropsychiatric adverse events attributable to varenicline or bupropion relative to nicotine patch or placebo. Varenicline was more effective than placebo, nicotine patch, and bupropion in helping smokers achieve abstinence, whereas bupropion and nicotine patch were more effective than placebo.

FUNDING

Pfizer and GlaxoSmithKline.

Genetic Diversity and Protective Efficacy of the RTS,S/AS01 Malaria Vaccine

BACKGROUND

The RTS,S/AS01 vaccine targets the circumsporozoite protein of Plasmodium falciparum and has partial protective efficacy against clinical and severe malaria disease in infants and children. We investigated whether the vaccine efficacy was specific to certain parasite genotypes at the circumsporozoite protein locus.

METHODS

We used polymerase chain reaction-based next-generation sequencing of DNA extracted from samples from 4985 participants to survey circumsporozoite protein polymorphisms. We evaluated the effect that polymorphic positions and haplotypic regions within the circumsporozoite protein had on vaccine efficacy against first episodes of clinical malaria within 1 year after vaccination.

RESULTS

In the per-protocol group of 4577 RTS,S/AS01-vaccinated participants and 2335 control-vaccinated participants who were 5 to 17 months of age, the 1-year cumulative vaccine efficacy was 50.3% (95% confidence interval [CI], 34.6 to 62.3) against clinical malaria in which parasites matched the vaccine in the entire circumsporozoite protein C-terminal (139 infections), as compared with 33.4% (95% CI, 29.3 to 37.2) against mismatched malaria (1951 infections) (P=0.04 for differential vaccine efficacy). The vaccine efficacy based on the hazard ratio was 62.7% (95% CI, 51.6 to 71.3) against matched infections versus 54.2% (95% CI, 49.9 to 58.1) against mismatched infections (P=0.06). In the group of infants 6 to 12 weeks of age, there was no evidence of differential allele-specific vaccine efficacy.

CONCLUSIONS

These results suggest that among children 5 to 17 months of age, the RTS,S vaccine has greater activity against malaria parasites with the matched circumsporozoite protein allele than against mismatched malaria. The overall vaccine efficacy in this age category will depend on the proportion of matched alleles in the local parasite population; in this trial, less than 10% of parasites had matched alleles. (Funded by the National Institutes of Health and others.).

Effect of varenicline on smoking cessation through smoking reduction: a randomized clinical trial

IMPORTANCE

Some cigarette smokers may not be ready to quit immediately but may be willing to reduce cigarette consumption with the goal of quitting.

OBJECTIVE

To determine the efficacy and safety of varenicline for increasing smoking abstinence rates through smoking reduction.

DESIGN, SETTING, AND PARTICIPANTS

Randomized, double-blind, placebo-controlled, multinational clinical trial with a 24-week treatment period and 28-week follow-up conducted between July 2011 and July 2013 at 61 centers in 10 countries. The 1510 participants were cigarette smokers who were not willing or able to quit smoking within the next month but willing to reduce smoking and make a quit attempt within the next 3 months. Participants were recruited through advertising.

INTERVENTIONS

Twenty-four weeks of varenicline titrated to 1 mg twice daily or placebo with a reduction target of 50% or more in number of cigarettes smoked by 4 weeks, 75% or more by 8 weeks, and a quit attempt by 12 weeks.

MAIN OUTCOMES AND MEASURES

Primary efficacy end point was carbon monoxide-confirmed self-reported abstinence during weeks 15 through 24. Secondary outcomes were carbon monoxide-confirmed self-reported abstinence for weeks 21 through 24 and weeks 21 through 52.

RESULTS

The varenicline group (n = 760) had significantly higher continuous abstinence rates during weeks 15 through 24 vs the placebo group (n = 750) (32.1% for the varenicline group vs 6.9% for the placebo group; risk difference (RD), 25.2% [95% CI, 21.4%-29.0%]; relative risk (RR), 4.6 [95% CI, 3.5-6.1]). The varenicline group had significantly higher continuous abstinence rates vs the placebo group during weeks 21 through 24 (37.8% for the varenicline group vs 12.5% for the placebo group; RD, 25.2% [95% CI, 21.1%-29.4%]; RR, 3.0 [95% CI, 2.4-3.7]) and weeks 21 through 52 (27.0% for the varenicline group vs 9.9% for the placebo group; RD, 17.1% [95% CI, 13.3%-20.9%]; RR, 2.7 [95% CI, 2.1-3.5]). Serious adverse events occurred in 3.7% of the varenicline group and 2.2% of the placebo group (P = .07).

CONCLUSIONS AND RELEVANCE

Among cigarette smokers not willing or able to quit within the next month but willing to reduce cigarette consumption and make a quit attempt at 3 months, use of varenicline for 24 weeks compared with placebo significantly increased smoking cessation rates at the end of treatment, and also at 1 year. Varenicline offers a treatment option for smokers whose needs are not addressed by clinical guidelines recommending abrupt smoking cessation.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01370356.

Functional interactions of varenicline and nicotine with nAChR subtypes implicated in cardiovascular control

INTRODUCTION

It has been suggested that varenicline-induced activation of nicotinic acetylcholine receptors (nAChRs) could play a role in the cardiovascular (CV) safety of varenicline. However, since preclinical studies showed that therapeutic varenicline concentrations have no effect in models of CV function, this study examined in vitro profiles of varenicline and nicotine at nAChR subtypes possibly involved in CV control.

METHODS

Concentration-dependent functional effects of varenicline and nicotine at human α3β4, α3α5β4, α7, and α4β2 nAChRs expressed in oocytes were determined by electrophysiology. The proportion of nAChRs predicted to be activated and inhibited by concentrations of varenicline (1mg b.i.d.) and of nicotine in smokers was derived from activation-inhibition curves for each nAChR subtype.

RESULTS

Human varenicline and nicotine concentrations can desensitize and inhibit nAChRs but cause only low-level activation of α3β4, α4β2 (<2%), α7 (<0.05%), and α3α5β4 (<0.01%) nAChRs, which is consistent with literature data. Nicotine concentrations in smokers are predicted to inhibit larger fractions of α3β4 (48%) and α3α5β4 (10%) nAChRs than therapeutic varenicline concentrations (11% and 0.6%, respectively) and to inhibit comparable fractions of α4β2 nAChRs (42%-56%) and α7 nAChRs (16%) as varenicline.

CONCLUSIONS

Nicotine and varenicline concentrations in patients and smokers are predicted to cause minimal activation of ganglionic α3β4* nAChRs, while their functional profiles at α3β4, α3α5β4, α7, and α4β2 nAChRs cannot explain that substituting nicotine from tobacco with varenicline would cause CV adverse events in smokers who try to quit. Other pharmacological properties that could mediate varenicline-induced CV effects have not been identified.

Association of deferring a quit attempt with smoking cessation success: a secondary analysis

Several smoking cessation treatments ask smokers to wait to quit to obtain treatment. We report a secondary analysis of whether a later quit attempt is associated with less success. In a placebo-controlled trial of varenicline that allowed smokers to set their quit date within 5 weeks after starting medication, 24% had their first quit attempt during week 1, and 27%, 19%, 18% and 12% in subsequent weeks. Continuous abstinence between 9 and 24 weeks declined over time; that is, from 36% to 37%, 35%, 29%, and 18% across the 5 weeks (p<0.001). The only statistically significant difference was between the last week and prior weeks. Whether a later quit attempt actually causes less success or is a marker for other variables (e.g., low motivation) is unclear.

Effects of varenicline on smoking cessation in adults with stably treated current or past major depression: a randomized trial

Chinese translation

BACKGROUND

Depression is overrepresented in smokers.

OBJECTIVE

To evaluate smoking abstinence and changes in mood and anxiety levels in smokers with depression treated with varenicline versus placebo.

DESIGN

Phase 4, multicenter, parallel, 1:1 allocation, double-blind, randomization trial. Randomization, stratified by antidepressant use and depression score at baseline, was blocked in sizes of 4. (ClinicalTrials.gov: NCT01078298).

SETTING

38 centers in 8 countries.

PARTICIPANTS

525 adult smokers with stably treated current or past major depression and no recent cardiovascular events.

INTERVENTION

Varenicline, 1 mg twice daily, or placebo for 12 weeks, with 40-week nontreatment follow-up.

MEASUREMENTS

Primary outcome was carbon monoxide-confirmed continuous abstinence rate (CAR) for weeks 9 to 12. Other outcomes included CARs assessed during nontreatment follow-up and ratings of mood, anxiety, and suicidal ideation or behavior.

RESULTS

68.4% versus 66.5% of the varenicline and placebo groups, respectively, completed the study. Varenicline-treated participants had higher CARs versus placebo at weeks 9 to 12 (35.9% vs. 15.6%; odds ratio [OR], 3.35 [95% CI, 2.16 to 5.21]; P < 0.001), 9 to 24 (25.0% vs. 12.3%; OR, 2.53 [CI, 1.56 to 4.10]; P < 0.001), and 9 to 52 (20.3% vs. 10.4%; OR, 2.36 [CI, 1.40 to 3.98]; P = 0.001). There were no clinically relevant differences between groups in suicidal ideation or behavior and no overall worsening of depression or anxiety in either group. The most frequent adverse event was nausea (varenicline, 27.0%; placebo, 10.4%). Two varenicline-group participants died during the nontreatment phase.

LIMITATIONS

Some data were missing, and power to detect differences between groups was low in rare events. Smokers with untreated depression, with co-occurring psychiatric conditions, or receiving mood stabilizers and antipsychotics were not included.

CONCLUSION

Varenicline increased smoking cessation in smokers with stably treated current or past depression without exacerbating depression or anxiety.

PRIMARY FUNDING SOURCE

Pfizer.

Effect of varenicline on individual nicotine withdrawal symptoms: a combined analysis of eight randomized, placebo-controlled trials

INTRODUCTION

Concerns exist that varenicline may cause neuropsychiatric side effects. Some of these symptoms (e.g., depression, irritability) have been measured in clinical trials using nicotine withdrawal scales. This study assessed the effect of varenicline on neuropsychiatric and other symptoms, as measured by the Minnesota Nicotine Withdrawal Scale (MNWS).

METHODS

We analyzed weekly individual MNWS symptom ratings in 8 randomized double-blind, placebo-controlled smoking cessation trials funded by Pfizer with similar methodology (n = 2,403 varenicline; n = 1,434 placebo). Ratings for the past 24hr were obtained prior to quitting and starting treatment and at Weeks 1-6 and 11 after the quit date.

RESULTS

In repeated measures analyses controlling for baseline values, ratings for 5 neuropsychiatric symptoms (depressed mood, irritability, anxiety, difficulty concentrating, and restlessness) and urge to smoke were lower (p < .01) for varenicline than placebo at each timepoint. Worsening in scores from 0-2 (baseline) to 4 was less frequent on varenicline than placebo for all ratings except appetite- (significantly more frequent for varenicline, p < .0001) and sleep-related items. Repeated measures analysis for individuals with low levels of exhaled carbon monoxide revealed similar patterns except for a nonsignificant difference for increased appetite.

CONCLUSIONS

Use of varenicline while trying to quit smoking reduces and does not increase neuropsychiatric symptoms such as depressed mood and irritability measured on the MNWS in smokers without current psychiatric disorders. It is associated with increases in sleep disturbance and appetite although the latter appears due to enabling more subjects to abstain from smoking.

A randomized placebo-controlled trial of varenicline for smoking cessation allowing flexible quit dates

INTRODUCTION

Current smoking cessation guidelines recommend setting a quit date prior to starting pharmacotherapy. However, providing flexibility in the date of quitting may be more acceptable to some smokers. The objective of this study was to compare varenicline 1 mg twice daily (b.i.d.) with placebo in subjects using a flexible quit date paradigm after starting medication.

METHODS

In this double-blind, randomized, placebo-controlled international study, smokers of ≥10 cigarettes/day, aged 18-75 years, and who were motivated to quit were randomized (3:1) to receive varenicline 1 mg b.i.d. or placebo for 12 weeks. Subjects were followed up through Week 24. Subjects were instructed to quit between Days 8 and 35 after starting medication. The primary endpoint was carbon monoxide-confirmed continuous abstinence during Weeks 9-12, and a key secondary endpoint was continuous abstinence during Weeks 9-24.

RESULTS

Overall, 493 subjects were randomized to varenicline and 166 to placebo. Continuous abstinence was higher for varenicline than for placebo subjects at the end of treatment (Weeks 9-12: 53.1% vs. 19.3%; odds ratio [OR] 5.9; 95% CI, 3.7-9.4; p < .0001) and through 24 weeks follow-up (Weeks 9-24: 34.7% vs. 12.7%; OR 4.4; 95% CI, 2.6-7.5; p < .0001). Serious adverse events occurred in 1.2% varenicline (none were psychiatric) and 0.6% placebo subjects. Fewer varenicline than placebo subjects reported depression-related adverse events (2.3% vs. 6.7%, respectively).

CONCLUSIONS

Varenicline 1 mg b.i.d. using a flexible quit date paradigm had similar efficacy and safety compared with previous fixed quit date studies.

Varenicline treatment for smoking cessation in Asian populations: a pooled analysis of placebo-controlled trials conducted in six Asian countries

OBJECTIVE

A pooled analysis to evaluate the efficacy and safety of varenicline versus placebo for smoking cessation in Asian populations. A secondary objective was to compare the data to pooled trials among predominantly Western populations.

RESEARCH DESIGN AND METHODS

Smokers (n = 893) in three randomized, double-blind, placebo-controlled, multicenter, phase IIb or III trials conducted in six Asian countries (Japan, Taiwan, Korea, China, Singapore, and Thailand), received varenicline (1 mg twice daily; n = 447) or placebo (n = 446) for 12 weeks. Non-treatment follow-up lasted 12 weeks (40 weeks in Japan). Primary endpoint was the carbon monoxide-confirmed continuous abstinence rate (CAR) for weeks 9-12 (last 4 weeks of treatment). Secondary endpoint was CAR for weeks 9-24.

RESULTS

CAR was higher for varenicline than placebo during weeks 9-12 (58.6 vs. 34.3%; odds ratio [OR]: 2.74; 95% confidence interval [CI]: 2.08-3.60; p < 0.0001), and through 12 weeks of follow-up (CAR weeks 9-24; 41.4 vs. 25.3%; OR: 2.08; 95% CI: 1.56-2.77; p < 0.0001). The most frequent adverse events (AEs) in the varenicline group (greater incidence than the placebo group) were: nausea (31.5%), headache (8.5%), dizziness (7.8%), insomnia (7.4%), and upper abdominal pain (5.4%). Serious AEs occurred in four varenicline and five placebo participants. Discontinuations due to AEs occurred in 3.6% of varenicline and 1.6% of placebo participants. Compared with the Western studies, abstinence rates for both varenicline and placebo were numerically higher in the Asian studies, although treatment effects were similar between the two populations. AEs reported in the Asian trials were largely similar to those in the Western populations.

CONCLUSIONS

Varenicline significantly improved smoking abstinence in Asian populations from six countries. AEs were predominantly of mild or moderate intensity. These data were largely the same as those seen in Western populations, but the studies were not designed to explore racial or cultural differences.