Dabigatran or warfarin for extended maintenance therapy of venous thromboembolism

BACKGROUND:

Extended treatment with warfarin is effective at prevent ing recurrent venous thromboembolism (VTE) but is associated with increased bleeding and is burdensome.

METHODS:

Patients with VTE who had initially received 3–12 months of anticoagulant therapy were randomized, using a double-blind design, to treatment with dabigatran 150 mg twice daily or with wafarin (to maintain an international normalized ratio of 2.0–3.0) for an additional period of 6–36 months. The primary efficacy outcome was the frequency of recurrent symptomatic VTE and related deaths at the end of the planned treatment period. Safety outcomes were bleeding events, acute coronary syndromes and other adverse events.

RESULTS:

Recurrent VTE occurred in 26 (1.8%) of 1430 patients treated with dabigatran and 18 (1.3%) of 1426 patients treated with war farin (hazard ratio [HR] 1.44; 95% confidence interval [CI], 0.78 2.64; P = 0.03 for the pre-specified non-inferiority margin). There were 13 major bleeds (0.9%) in patients on treatment with dabigatran and 25 (1.8%) in patients on treatment with warfarin (HR 0.52; 95% CI, 0.27–1.01). Any bleeding occurred in 277 patients (19%) on treat ment with dabigatran and in 373 patients (26%) on warfarin (HR 0.71; 95% CI, 0.61–0.83). Acute coronary syndromes were observed n 13 patients (0.9%) on treatment with dabigatran and in three patients (0.2%) on warfarin (P = 0.02). There were 17 deaths in the dabigatran group and 19 deaths in the warfarin group; other adverse events were also similar with the two treatments.

CONCLUSIONS:

Dabigatran was as effective as warfarin in the extended treatment of VTE. Dabigatran was associated with a reduced risk for bleeding but an increased incidence of acute coronary events. Disclosure of Interest: Anne Mathilde Kvamme and Janet Schnee are employees of Boehringer Ingelheim. All other authors have received honoraria from Boehringer Ingelheim for their work in the Steering Committee of studies on dabigatran in VTE.