SI-B037

SI-B037 is a bispecific antibody developed by SystImmune for the treatment of advanced solid tumors refractory to standard therapies. It is designed to target immunosuppression and other synergistic mechanisms within the tumor microenvironment. In September 2026, the U.S. Food and Drug Administration (FDA) cleared the Investigational New Drug (IND) application for SI-B037, allowing the initiation of a Phase 1/1b clinical trial to evaluate its safety, tolerability, pharmacokinetics, and clinical activity. Notably, the IND package for SI-B037 was the first from SystImmune to utilize New Approach Methodologies (NAMs)—including human organ-on-chip systems and primary human tissue models—in place of conventional animal toxicology studies, representing a modern, human-centric approach to nonclinical safety assessment.