The present study summarizes results of the efficacy and safety of monoclonal antibody (MAb) purified factor IX concentrate [Mononine® Coagulation Factor IX (Human), Centeon L.L.C., King of Prussia, PA, USA] for surgical prophylaxis in 74 patients with mild, moderate or severe haemophilia B who underwent a total of 81 different operative interventions. Surgical procedures included joint replacement/arthroplasty (n= 12), gastrointestinal (GI) or rectal surgery (n= 6), synovectomy/osteotomy (n= 8), hernia repair (n= 4), central catheter insertion (n= 3), ENT surgery (n= 4), dental procedures (n= 14), biopsies (n= 2), gynaecological procedures (n= 4), ophthalmological surgery (n= 4), spinal surgery (n= 4), urogenital surgery (n= 2), other orthopaedic surgery (n= 4) or other miscellaneous procedures (n= 10). All patients demonstrated haemostasis rated as 'excellent' by the investigators. No patients experienced clinically evident thromboembolic complications during treatment with MAb factor IX. These results, from a large and varied random group of patients, demonstrate that this highly purified factor IX concentrate is safe and effective for surgical prophylaxis in patients with haemophilia B, including those patients who have experienced thromboembolic complications during prior treatment with prothrombin complex concentrates.