In patients with cancer and venous thromboembolism (VTE) events, prophylaxis of recurrence with direct oral anticoagulants (DOACs) was noninferior to low-molecular-weight heparins (LMWHs), a study shows. “These findings support use of a DOAC to prevent recurrent VTE in patients with cancer,” the authors conclude.
The pragmatic, unblinded, comparative effectiveness, noninferiority randomized clinical trial included 638 patients from 67 centers with cancer and new VTEs. Types of cancer included any invasive solid tumor, lymphoma, multiple myeloma, or chronic lymphocytic leukemia. Participants were randomized to a DOAC or LMWH (or fondaparinux) based on the physician’s or patient’s choice and were followed for 6 months or until death.
With a primary outcome of the recurrent VTE rate at 6 months, the study showed: “Between December 2016 and April 2020, 671 participants were randomized and 638 (95%) completed the trial (median age, 64 years; 353 women [55%]). Among those randomized to a DOAC, 330 received at least 1 dose. Among those randomized to LMWH, 308 received at least 1 dose. Rates of recurrent VTE were 6.1% in the DOAC group and 8.8% in the LMWH group (difference, −2.7%; 1-sided 95% CI, −100% to 0.7%) consistent with the prespecified noninferiority criterion. Of 6 prespecified secondary outcomes, none were statistically significant. Major bleeding occurred in 5.2% of participants in the DOAC group and 5.6% in the LMWH group (difference, −0.4%; 1-sided 95% CI, –100% to 2.5%) and did not meet the noninferiority criterion. Severe adverse events occurred in 33.8% of participants in the DOAC group and 35.1% in the LMWH group. The most common serious adverse events were anemia and death.”