Oral Presentation No. 107
Achieving higher efficacy without compromising safety with Factor XI inhibitors versus low-molecular-weight heparin for the prevention of venous thromboembolism in major orthopedic surgery – Systematic Review and Meta-Analysis

In recent years, many important advances have been seen in anticoagulation therapy. However, bleeding risk is still a major concern. Factor XI inhibition has emerged as a potential advantageous target to minimize this risk.

We conducted a systematic review and meta-analysis of current evidence on factor XI inhibitors for thromboprophylaxis in major orthopedic surgery.

We performed a systematic search of electronic databases (Pubmed, CENTRAL, and Scopus) until May of 2022. Studies were considered eligible if they were RCTsevaluating factor XI inhibitors in thromboprophylaxis vs. low-molecular-weight heparins (LMWH). For analysis purposes, we considered efficacy (Venous Thromboembolism [VTE], symptomatic VTE) and safety (major and clinically relevant non-major [CRNM] bleeding events; major bleeding events; blood transfusion necessities; adverse events; major adverse events) outcomes.

Overall, 4 RCTs were included, with a total of 2269 patients, 372 VTE events, and 50 major or CRNM bleeding events. Regarding efficacy outcomes, factor XI inhibitors were associated with a significant reduction in the incidence of VTE events (OR 0.50; 95%CI [0.36, 0.69]). Concerning safety outcomes, factor XI inhibitors significantly reducedmajor or CRNM bleeding events (OR 0.41 [0.22; 0.75]). It was also associated with a lower percentage of patients needing a blood transfusion, despite not meeting statistical significance (OR 0.69; 95%CI [0.32; 1.48]). Incidence of adverse events and major adverse events were similar between groups.

Factor XI inhibitors showed a significant reduction in the incidence of VTE and bleeding events among patients submitted to major orthopedic surgery.