DOAC - Dosing Options in AntiCoagulation Prophylaxis

Apixaban, a direct oral anticoagulant (DOAC), will be administered at a prophylactic dose of 2.5 mg by mouth twice daily for 6 months. This dose is guideline-recommended for VTE prevention in high-risk ambulatory cancer patients. Participants will continue their cancer-directed therapy during this time. No study-mandated visits or labs are required beyond standard care.

Apixaban will be administered at 5 mg by mouth once daily for 6 months. This alternative prophylactic schedule is being studied to assess its effectiveness and adherence in patients with a Khorana Risk Score of 2. Participants will continue their usual cancer treatment. This arm evaluates a simplified dosing strategy in a real-world, pragmatic design.

Participants randomized to this arm will not receive apixaban or any other anticoagulant for VTE prevention. This reflects current standard care for many cancer outpatients with moderate risk (Khorana Score = 2). Outcomes will be monitored through routine care and medical record abstraction.