Abstract 14063: Eight Pharmacokinetic-Related Genetic Variants Were Not Associated With Bleeding From Direct Oral Anticoagulants in Non-Valvular Atrial Fibrillation Patients

Abstract

Background. Atrial fibrillation (AF) is the leading cause of ischemic stroke and treatment has focused on reducing stroke risk through anticoagulation. Direct Oral Anticoagulants (DOACs) are the first-line guideline-recommended therapy in non-valvular AF since they are as effective and safer than warfarin. Although patients bleed less overall from DOACs, bleeding still is the main safety concern with this therapy. Previous studies have shown that genetic variants modify the function of metabolic enzymes or transporters involved in the pharmacokinetics (PK) of DOACs, which then affect DOAC plasma concentrations. However, whether those functional PK genetic variants are significantly associated with the risk of bleeding on DOACs is unknown. Aim. Assess the association of PK-related single nucleotide variants (SNVs) with the risk of bleeding from DOACs in non-valvular AF patients. Methods. A retrospective cohort study was carried out with 2,364 Caucasians with non-valvular AF and treated with rivaroxaban or apixaban. Patients were genotyped as part of the genomic biobank at the University of Michigan Health System. The primary endpoint was a composite of major and clinically relevant non-major (CRNM) bleeding. Cox proportional hazards regression with time-varying analysis assessed the association of 8 SNVs in 5 PK genes ( ABCB1 , ABCG2 , CYP3A4 , CYP3A5 , CYP2J2 ) with the risk of bleeding from DOACs in unadjusted and covariate-adjusted models. Six tests were performed as 3 of the SNVs are in the same haplotype. P-values below the Bonferroni-corrected level of 8.33e-3 were considered statistically significant. Results. A total of 412 (17.4%) major and CRNM bleeding events occurred over 2.27 ± 2.03 years of follow-up. None of the PK SNVs were significantly associated with bleeding risk on DOACs (Table 1). Conclusion. SNVs that affect the function of PK genes were not significantly associated with major and CRNM bleeding from rivaroxaban or apixaban in 2,364 AF patients.