Efficacy and Safety of Rivaroxaban Versus Warfarin in Patients Taking Nondihydropyridine Calcium Channel Blockers for Atrial Fibrillation (from the ROCKET AF Trial)

Abstract

Non-dihydropyridine calcium channel blockers (non-DHP CCBs) possess combined P-glycoprotein and moderate CYP3A4 inhibition, which may lead to increased exposure of medications that are substrates for these metabolic pathways, such as rivaroxaban. We evaluated the use and outcomes of non-DHP CCBs in patients with atrial fibrillation (AF) in Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET AF). We assessed clinical outcomes in patients who received non-DHP CCBs and the impact on the efficacy and safety of rivaroxaban compared with warfarin. Stroke or noncentral nervous system (CNS) systemic embolism (SE), major or nonmajor clinically relevant (NMCR) bleeding, all-cause death, and major bleeding were compared according to non-DHP CCB use. At randomization, 1,308 patients (9.2%) were taking a non-DHP CCB. They were more likely to be women, have diabetes and COPD, and less likely to have heart failure and had a lower mean CHADS2 score (3.3 vs 3.5). Non-DHP CCB use was not associated with an increased risk of stroke/non-CNS SE (p= 0.11) or the composite outcome of NMCR or major bleeding (p= 0.087). Non-DHP CCB use was associated with an increased risk of major bleeding (adjusted hazard ratio 1.50, 95% CI 1.11 to 2.04) and intracranial hemorrhage (adjusted hazard ratio 2.84, 95% CI 1.53 to 5.29). No significant difference was observed in the primary efficacy (stroke or non-CNS SE; adjusted interaction p value= 0.38) or safety outcome (NMCR or major bleeding; adjusted interaction p value= 0.14) between rivaroxaban and warfarin with non-DHP CCB use. In conclusion, although the overall use of non-DHP CCBs was associated with an increased risk of major bleeding and intracranial hemorrhage, the use was not associated with a significant change in the safety or efficacy of rivaroxaban compared with warfarin observed in ROCKET AF.