Long-term safety profile of sutimlimab in adult Japanese patients with cold agglutinin disease.

Sutimlimab, a complement inhibitor, has recently been approved in Japan for treating cold agglutinin disease (CAD). We report the safety and efficacy of sutimlimab in Japanese patients with CAD who completed a global phase 3 clinical trial (CARDINAL/CADENZA: 26-week treatment with 1-2 years of open-label extension [OLE] periods) and subsequently participated in the Japanese OLE study. Patients with a recent history of blood transfusion (CARDINAL, n = 3) and those without (CADENZA, n = 4) were analyzed (71.4% female; median [range] baseline age: 70 [46-83] years). For CARDINAL/CADENZA, the treatment duration (median [range]) was 140.9 (104.9-157.3) weeks, and the cessation period was 70 (61-133) weeks. For the Japanese OLE study, the treatment duration was 47.1 (15.1-49.1) weeks. Three (42.9%) patients experienced treatment-related and treatment-emergent adverse events (TEAEs): injection site erythema, cystitis bacterial, viral infection, and blood pressure increased during CARDINAL/CADENZA. One (14.3%) patient experienced one treatment-related TEAE (urinary tract infection) during the Japanese OLE study. One patient died of renal failure, considered unrelated to sutimlimab, that was exacerbated by hepatorenal syndrome due to liver cirrhosis and bacterial peritonitis, in addition to CKD. Hemoglobin and bilirubin levels improved during treatment but deteriorated after withdrawal and recovered on retreatment. Sutimlimab was well tolerated over a median of 3.8 years, with no new safety concerns identified during retreatment.