MORAb-109

MORAb-109 is an investigational antibody-drug conjugate (ADC) developed by Eisai Inc. that targets human mesothelin, a cell surface glycoprotein overexpressed in various solid tumors including mesothelioma, pancreatic cancer, and non-small cell lung carcinoma. The drug consists of a humanized anti-mesothelin monoclonal antibody conjugated to eribulin, a microtubule dynamics inhibitor, with a drug-to-antibody ratio (DAR) of 2. Upon binding to mesothelin on the tumor cell surface, the ADC is internalized, and the eribulin payload is released, leading to cell cycle arrest and apoptosis. Preclinical studies have demonstrated selective cytotoxicity and dose-dependent anti-tumor activity in multiple xenograft models, particularly in gynecologic and gastrointestinal malignancies.