Adherence and persistence to rivaroxaban in non-valvular atrial fibrillation patients receiving 30- or 90-day supply prescription fills

Abstract

Background: It is unclear whether 90-day supply fills with rivaroxaban result in better adherence and persistence compared to 30-day supply fills. We assessed patients’ adherence and persistence to rivaroxaban at 12- and 24-months in nonvalvular atrial fibrillation (NVAF) patients whose rivaroxaban prescriptions were filled every 30- vs. 90-days. Methods: Using the IBM MarketScan Commercial and Medicare Supplemental data sets, we identified adult NVAF patients with ≥12-months of continuous insurance coverage who filled a prescription in May 2018 and their immediate subsequent prescription for rivaroxaban for the same days’ supply. We propensity score-matched 30- and 90-day rivaroxaban interval fill patients and compared the percentage with a proportion of days covered (PDC) ≥80%, mean PDC, and percentage persistent to rivaroxaban therapy over 12- and 24-months of follow-up. Results: Following propensity score matching, 2237 patients were included in the rivaroxaban 30- and 90-day supply fill cohorts. The proportion of patients with a PDC ≥80% was greater in the 90-day vs. 30-day cohort at both 12-months (odds ratio [OR] = 1.75, 95% confidence interval [CI] = 1.54–1.97) and 24-months (OR = 1.78, 95%CI = 1.58–2.00), as were mean PDC values (absolute difference in mean PDC = 9.4%, 95%CI = 8.2–10.7% at 12-months and 11.2%, 95%CI = 9.5–12.9% higher at 24-months, respectively). Persistence to rivaroxaban was not found to significantly differ between the 30- and 90-day supply cohorts at 12- or 24-months (assuming a 30-day permissible gap); however, greater persistence was observed with 90-day fills at both time points when a 14-day gap was utilized (HR = 1.22, 95%CI = 1.10–1.36 at 12-months and HR = 1.12, 95%CI = 1.02–1.22 at 24-months). Conclusions: Dispensing 90-day supply fills with rivaroxaban appears to increase the proportion of patients achieving acceptable (PDC ≥80%) adherence as well as mean adherence compared to 30-day supply fills. Ninety-day rivaroxaban fills may also result in improved persistence vs. 30-day fills.