High Number of Newly Initiated Direct Oral Anticoagulant Users Switch to Alternate Anticoagulant Therapy

Real-world evidence focusing on medication switching patterns amongst direct oral anticoagulant (DOACs) has not been well studied. The objective of this study is to evaluate patterns of prescription switching in non-valvular atrial fibrillation (NVAF) patients initiated on a DOAC and previously naïve to anticoagulation (AC) therapy. Data was obtained from Truven Health MarketScan Commercial and Medicare Supplemental database (2009-2013). AC naïve (those without prior anticoagulant use) NVAF patients initiated on a DOAC, with 6 months of continuous health plan enrollment before and after treatment initiation and maintained on continuous therapy for a minimum of 6 months were included. Of 34,022 AC naïve NVAF patients initiating a DOAC, 6613 (19.4%) patients switched from an index DOAC prescription to an alternate anticoagulant and 27,409 (80.6%) remained on the DOAC [age: 68.5 ± 11.7 vs. 67.1 ± 12.7 years, p < 0.001; males: 3781 (57.2%) vs. 17,160 (62.6%), p < 0.001]. Amongst those that switched medication, 3196 (48.3%) did so within the first 6 months of therapy. Overall, 2945 (44.5%) patients switched to warfarin, 2912 (44.0%) switched to another DOAC and 756 (11.4%) switched to an injectable anticoagulant. The highest proportion of patients switched from dabigatran to warfarin (N = 2320; 42.5%) or rivaroxaban (N = 2252; 41.3%). The median time to switch from the index DOAC to another DOAC was 309.5 days versus 118.0 days (p < 0.001) to switch to warfarin. In NVAF patients newly initiated on DOAC therapy, one in five patients switch to an alternate anticoagulant and one of every two patients do so within the first 6 months of therapy. Switching from an initial DOAC prescription to traditional anticoagulants occurs as frequently as switching to an alternate DOAC.