Edoxaban for 12 vs. 3 months in cancer-associated isolated distal deep vein thrombosis according to different doses: insights from the ONCO DVT study

Background The ONCO DVT study revealed the superiority of 12-month relative to 3-month edoxaban treatment for cancer-associated isolated distal deep vein thrombosis (DVT) regarding the thrombotic risk.Methods and Results In this pre-specified subgroup analysis of the ONCO DVT study, we stratified the patients into those with a standard edoxaban dose (60 mg/day; N = 151) and those with a reduced edoxaban dose (30 mg/day; N = 450) and evaluated the clinical outcomes for the 12- and 3-month treatments. The cumulative 12-month incidence of symptomatic recurrent venous thromboembolism was lower in the 12-month than 3-month group for both the 60 mg (1.3% vs. 11.6%, P = 0.02; odds ratio [OR], 0.12; 95% confidence interval [CI], 0.01-0.97) and 30 mg (1.1% vs. 7.6%, P = 0.002; OR, 0.14; 95% CI, 0.03-0.60) edoxaban subgroups, which was consistent across the edoxaban doses without a significant interaction (P = 0.90). The 12-month cumulative incidence of major bleeding was higher in the 12-month group than in the 3-month group for the 60 mg edoxaban subgroup (14.3% vs. 4.4%, P = 0.046; OR, 3.61; 95% CI, 0.97-13.52), whereas it did not significantly differ between the two groups for the 30 mg edoxaban subgroup (8.7% vs. 8.6%, P = 0.89; OR, 0.97; 95% CI, 0.49-1.91), signalling there was a potential interaction (P = 0.07).Conclusions A 12-month edoxaban regimen for cancer-associated isolated distal DVT was consistently superior to a 3-month regimen, across the edoxaban doses for the thrombotic risk. However, caution was suggested for the standard dose of edoxaban due to the potential for an increased risk of bleeding with prolonged anticoagulation therapy.Trial registration number NCT03895502 (ONCO DVT Trial): https://classic.clinicaltrials.gov/ct2/show/NCT03895502