Archief Roodbont

Rivaroxaban, an oral factor Xa inhibitor that is not yet FDA approved, is one of several new potential substitutes for warfarin. In this report, researchers present the results of two industry-sponsored trials that involved rivaroxaban.

In one study, 3449 patients with acute symptomatic proximal deep venous thrombosis (DVT) — but without clinically apparent pulmonary embolism — were randomized to receive either oral rivaroxaban or standard therapy (enoxaparin followed by warfarin); treatment duration was 3 to 12 months. The incidence of recurrent venous thromboembolism was slightly lower with rivaroxaban than with standard therapy (2.1% vs. 3.0%), and the incidence of bleeding was the same in both groups.

In another study, 1197 patients who had completed 6 to 12 months of treatment for acute venous thromboembolism were randomized to receive either oral rivaroxaban or placebo for 6 to 12 additional months. Recurrent venous thromboembolism occurred significantly less often with rivaroxaban than with placebo (1.3% vs. 7.1%); DVT accounted for most of the difference. Rivaroxaban recipients experienced fewer pulmonary embolic events than did placebo recipients (3 vs. 14) but suffered more major bleeding episodes (4 vs. 0).

Comment: Fully oral treatment with rivaroxaban is a safe and effective alternative to standard acute DVT therapy, and it simplifies treatment. Not surprisingly, extending treatment beyond 6 to 12 months prevents recurrent venous thromboembolism while posing a small but finite bleeding risk — as would be expected for any antithrombotic agent. This study establishes that rivaroxaban could be used for indefinite prophylaxis, but it doesn't identify patient subgroups for which benefits of indefinite therapy outweigh risks.

— Allan S. Brett, MD

Published in Journal Watch General Medicine December 21, 2010