Zenas BioPharma announced this week that it is partnering with Bristol Myers Squibb to develop and market obexelimab, a bi-functional antibody, in multiple Asian-Pacific countries.
Per the deal, BMS will receive exclusive rights to develop and commercialize obexelimab in Japan, South Korea, Taiwan, Singapore, Hong Kong and Australia. Zenas will secure an initial payment of $50 million, an equity investment, and the possibility of additional payments based on reaching specific development milestones, as well as royalties.
Obexelimab is an investigational bifunctional, non-cytolytic, humanized monoclonal antibody that binds CD19 and FcγRIIb to inhibit B cells, plasmablasts, and CD19-expressing plasma cells. It is currently undergoing phase 3 trials for IgG4-related disease and phase 2/3 trials for autoimmune hemolytic anemia.
IgG4-related disease is a chronic immune-mediated ailment affecting multiple organs. Warm autoimmune hemolytic anemia is a form of autoimmune hemolytic anemia where IgG autoantibodies attach to red blood cells, leading to their early destruction. It accounts for 70-80% of cases among autoimmune hemolytic anemias. Approximately 40,000 individuals in the U.S. and another 40,000 in the EU are affected by this condition, and although initial treatment often produces positive results, approximately 75% of patients eventually become unresponsive to therapy.
Zenas had snapped up the rights to obexelimab from Xencor in 2021, shortly after Novartis had walked away from a $2.6 billion collaboration with Xencor.
