SYN101

SYN101 is an immune cell-targeted antibody-drug conjugate (ADC) developed by Synthis Therapeutics. It consists of an antibody directed against immune cells conjugated to Synthis-003, a non-cytotoxic small molecule inhibitor of ALK5 (TGF-β receptor type I). The mechanism of action involves the targeted delivery of the ALK5 inhibitor to immune cells within the tumor microenvironment, where it blocks TGF-β signaling to alleviate immunosuppression and enhance the anti-tumor immune response. This approach aims to provide the therapeutic benefits of TGF-β pathway inhibition while avoiding the systemic toxicities, such as cardiac toxicity, typically observed with global ALK5 inhibition. SYN101 is currently in IND-enabling preclinical development for the treatment of solid tumors, including bladder cancer, colorectal cancer, and triple-negative breast cancer.