Thromboprophylaxis with rivaroxaban in patients with malignancy and central venous lines (TRIM-Line): A two-center open-label pilot randomized controlled trial

Background: Central venous catheter (CVC) insertion is an important risk factor for venous thromboembolism (VTE) among patients with cancer. Routine use of primary thromboprophylaxis in this patient population is not currently recommended. We sought to assess the feasibility of conducting a randomized controlled trial (RCT) assessing the safety and efficacy of rivaroxaban (10 mg daily) to prevent VTE complications in this patient population.

Methods: This is a two-center prospective, randomized, open blinded end point pilot trial including patients with active cancer and a newly inserted CVC. Patients were randomly assigned 1:1 to rivaroxaban or observation for 90 days. The primary feasibility outcome of this pilot study was the number of participants recruited per month. Secondary clinical outcomes included thrombotic complications, major VTE, and major bleeding episodes.

Results: Overall, 105 patients were enrolled over 11 months. The average enrollment rates were 7.5 and 2 patients per month at the two participating centers, respectively. Overall, thrombotic complications occurred in 3 patients in the rivaroxaban group (5.8%; 95% confidence interval [CI], 1.2-16.0) compared with 5 patients in the control group (9.4%; 95% CI, 3.1-20.7) (HR, 0.58; 95% CI, 0.14-2.5). Major VTE occurred in 2 (3.9%; 95% CI, 0.5-13.2) and 3 (5.7%; 95% CI, 1.2-15.7) patients in the rivaroxaban and control group, respectively (HR, 0.66; 95% CI, 0.11-3.9). One patient (1.9%) receiving rivaroxaban had a major bleeding event.

Conclusions: Thrombotic complications are common in patients with cancer and a newly inserted CVC. The pilot trial achieved its enrollment targets and supports that a large multicenter RCT is feasible in this area. ClinicalTrials.gov (NCT03506815).