Objective: We systematically assessed the efficacy of Concizumab in patients with Hemophilia A/B. Material and Methods: Five databases were searched up to May 2022 for randomized controlled trials in adults with severe Hemophilia A/B with or without inhibitors treated with Concizumab compared to standard care or placebo. Outcomes were bleeding episodes (ABRs), D - dimer, prothrombin fragment 1.2, fibrinogen levels, prothrombin time, nasopharyngitis, and upper respiratory tract infection. Results: Two RCTs (n = 86) were included. In both studies, decreased bleeding rates were observed at high levels of concizumab. Furthermore, both studies support the use of concizumab as a safe and well-tolerated prophylactic therapy administered subcutaneously in all haemophilia patients. Placebo was the comparator in one RCT, while Eptacog alfa (activated) rFVIIIa was the comparator in the other RCT. T...