Zenyaku And Chugai Secure Japan’s MHLW Approval Of Rituxan For Autoimmune Hemolytic Anaemia In Public Knowledge-Based Expansion

Zenyaku Kogyo Co., Ltd. and Chugai Pharmaceutical Co., Ltd. announced that Japan’s Ministry of Health, Labour and Welfare has approved an additional indication for Rituxan® intravenous injection (rituximab) for the treatment of autoimmune haemolytic anaemia (AIHA). Rituxan, an anti-CD20 monoclonal antibody, is co-marketed by both companies in Japan. The approval follows a public knowledge-based application process after development requests were submitted by the Japanese Society of Haematology and the Japanese Society of Pediatric Haematology/Oncology.

The request for expanded use was reviewed at the “64th Evaluation Committee on unapproved or off-label drugs with high medical needs” in July 2025 and subsequently endorsed by the Pharmaceutical Affairs Council’s First Committee on Drugs. Zenyaku filed the public knowledge-based application in August 2025, leading to the newly granted approval. This pathway is designed to accelerate access to treatments that address significant unmet medical needs.

AIHA is a rare, government-designated intractable disease in Japan (No. 61), characterised by the destruction of red blood cells due to autoantibodies targeting red blood cell membrane antigens. The disease is broadly categorised into warm AIHA, which occurs at near-normal body temperature, and cold AIHA, including cold agglutinin disease (CAD) and paroxysmal cold hemoglobinuria (PCH), which occur at lower temperatures. While corticosteroids are effective in many warm AIHA cases, relapse is common, often requiring long-term therapy or splenectomy. In cold AIHA, supportive warming measures are standard, but severe anaemia and transfusion dependence may develop. Clinical guidelines in Japan and internationally recommend rituximab as a treatment option for relapsed, refractory, or severe cases.