Abelacimab outperforms rivaroxaban for AF patients at risk of stroke

In the treatment of patients with atrial fibrillation (AF) and moderate-to-high risk of stroke, abelacimab appears more beneficial than rivaroxaban, having been associated with lower free factor XI levels and fewer bleeding events in the phase IIB AZALEA–TIMI 71 study.

AZALEA–TIMI 71 involved 121 patients (median age 74 years, 44 percent women) who were randomly assigned to receive treatment with subcutaneous injection of abelacimab (150 mg or 90 mg once monthly) or oral rivaroxaban (20 mg once daily). Abelacimab was administered in a blinded fashion, and rivaroxaban, in an open-label fashion.

Over a median follow-up of 2.1 years, the primary endpoint of major or clinically relevant nonmajor bleeding occurred less frequently with both 150-mg and 90-mg abelacimab than with rivaroxaban (3.2 and 2.6 vs 8.4 events per 100 person-years).

Compared with rivaroxaban, abelacimab 150 or 90 mg was associated with a more than 60-percent reduction in the risk of the primary endpoint (150 mg: hazard ratio [HR], 0.38, 95 percent confidence interval [CI], 0.24–0.60; HR, 0.31, 95 percent CI, 0.19–0.51; p<0.001 for both comparisons.

At 3 months, free factor XI levels decreased by a median of 99 percent with abelacimab 150 mg and by 99 percent with the 90-mg dose.

In terms of safety, no significant differences were seen in the incidence and severity of adverse events (AEs), serious AEs, and AEs leading to drug discontinuation across the three treatment arms.