Patients who took rivaroxaban for three months were less likely to get clots than those on a standard, shorter course, new research suggests.
Longer anti-clotting treatment is more effective at managing isolated distal deep vein thrombosis than a short course, experts say.
A recent study by German researchers found that patients were at a lower risk of developing recurrent venous thromboembolism after an additional six weeks of treatment with anticoagulant rivaroxaban, with no greater risk of haemorrhage.
The randomised, double-blind, placebo-controlled clinical trial included 402 adults with symptomatic isolated distal deep vein thrombosis.
All participants received a standard dose of rivaroxaban for six weeks, before being assigned to receive either rivaroxaban 20mg once daily or placebo once daily for an additional six weeks.
Of the 200 adults who received additional rivaroxaban treatment, 11% experienced recurrent venous thromboembolism compared to 19% in the placebo arm, during the 24-month follow-up period.
Furthermore, recurrent isolated distal deep vein thrombosis occurred in 8% of patients in the rivaroxaban group and 15% in placebo.
Proximal deep vein thrombosis or pulmonary embolism occurred in 3% of patients in the rivaroxaban arm and 4% in the placebo arm.
No major bleeding events were observed as a result of the treatment regime.
“Rivaroxaban administered for three months effectively and safely reduces the risk of recurrent venous thromboembolism compared with rivaroxaban administered for six weeks in patients with isolated distal deep vein thrombosis,” the authors wrote.
“This benefit was mainly driven by recurrent isolated distal deep vein thrombosis, maintained during the 24-month follow-up, and was consistent among patient subgroups.
These findings do not apply to patients with cancer associated isolated distal deep vein thrombosis, who were excluded from the study and should not be extrapolated to other anticoagulant treatments.”
“Extended treatment with rivaroxaban was associated with significantly higher rates of complete clot resolution. This finding is potentially relevant given the role of residual vein obstruction in the development of the post-thrombotic syndrome,” they said.
