Antithrombotic secondary prophylaxis with low dose of apixaban or rivaroxaban in the onco-hematologic patients: comparison with non-neoplastic patients.

Management of cancer-associated thrombosis (CAT) is usually performed employing low molecular weight heparin (LMWH) or direct oral anticoagulants (DOACs). Low-intensity DOACs are the mainstay for extended duration therapy for VTE in non-oncologic patients. The aim of our study was to evaluate the efficacy and the safety of low doses of apixaban or rivaroxaban as secondary prophylaxis in patients affected by hematological malignancies with follow-up > 12 months. We report an observational, retrospective, single-center study that evaluated consecutive patients referred to our center between January 2016 and January 2023. The DOACs were administered at full dose during the acute phase of VTE and then at low dose for the extended phase. We included 154 patients: 53 patients affected by hematological malignancies compared to 101 non-neoplastic patients. During full-dose treatment, no thrombotic recurrences were observed in the two groups. During low-dose therapy, 2 (1.9%) thrombotic events (tAE) were observed in the control group. During full-dose treatment, the rate of bleeding events (bAE) was 9/154 (5.8%): 6/53 (11%) in hematological patients and 3/101 (2.9%) in non-hematological patients (p = 0.0003). During low-dose therapy, 4/154 (2.6%) bAE were observed: 3/53 (5.5%) in the hematologic group and 1 (1%) in the control group (p = 0.07). We found encouraging data on the safety and efficacy of low doses of DOACs as secondary prophylaxis in the onco-hematologic setting; no thrombotic complications were observed, and the incidence of hemorrhagic events was low.