An unblinded comparative effectiveness study found that direct oral anticoagulants (DOACs) were non-inferior to low-molecular-weight heparin (LMWH) for preventing recurrent venous thromboembolism (VTE) events among a population of patients with various cancers. The 6-month rate of VTE recurrence was 6.1% with DOACs versus 8.8% with LMWH.
The study’s first author, Deborah Schrag, MD, MPH, noted that previous trials compare specific DOACs with LMWHs. However, this trial more accurately represented routine practice by allowing physicians and patients to choose a DOAC or LMWH (or fondaparinux) and modify doses or discontinue treatment for procedures. Findings from the study were reported in JAMA.
Between December 2016 and April 2020, the trial enrolled 671 patients from 67 US centers with cancer and a new diagnosis of VTE. Cancer diagnoses included invasive solid tumors, lymphoma, multiple myeloma, or chronic lymphocytic leukemia.
DOACs Comparable to LMWH for Anticoagulation in Cancer Patients
A total of 638 (95%) patients completed the trial (median age, 64 years; 55% female), of which 330 and 308 received at least 1 dose of DOAC or LMWH, respectively. The primary endpoint was VTE recurrence at 6 months, and noninferiority for DOACs versus LMWH was defined as a less than 3% difference in the upper limit of the 1-side 95% confidence interval (CI).
The between-group difference of -2.7% (95% CI, -100 to 0.7) for DOACs versus LMWH met the prespecified noninferiority threshold for preventing VTE recurrence in patients with cancer. The study’s authors noted no statistically significant differences between the groups for 6 secondary endpoints.
Major bleeding was reported in 5.2% of participants in the DOAC group versus 5.6% in the LMWH group (difference, -0.4%; 95% CI, -100 to 2.5), which did not meet prespecified noninferiority criteria. Severe adverse events occurred in 33.8% and 35.1% of DOAC and LMWH participants, respectively.
Ultimately, the researchers supported using DOACs to prevent VTE recurrence after acute events in patients with cancer and highlighted the potential advantages of oral treatments versus the subcutaneously administered LMWH.