Redmond – September 22, 2026 -- SystImmune Inc. has secured U.S. Food and Drug Administration clearance for its Investigational New Drug application for SI-B037, a bispecific antibody, marking the first time the company has built a regulatory submission entirely on New Approach Methodologies (NAMs) rather than traditional animal toxicology studies.
SystImmune replaces animal testing with human organ-on-chip models
The IND package for SI-B037 relied on human organ-on-chip systems and primary human tissue models instead of conventional animal studies to assess nonclinical safety. Dr. Jahan Khalili, Senior Vice President of Research at SystImmune, said the human-relevant models provided a more direct read on a molecule engineered to engage multiple human pathways simultaneously.
SI-B037 is designed to target immunosuppression and other synergistic mechanisms through a bispecific antibody structure. The clearance places SystImmune among a small group of biotech developers aligning with regulatory momentum toward non-animal testing alternatives, a shift authorities worldwide have increasingly encouraged for biologics development.
Company to launch Phase 1/1b trial for refractory solid tumors
SystImmune plans to move directly into a Phase 1/1b clinical trial to determine optimal dosing and characterize the clinical activity of SI-B037. Dr. Anand Achanta, Senior Vice President of Regulatory Affairs and Medical Writing, said the trial targets patients with advanced solid tumors refractory to standard therapies, a population he described as having urgent need for novel options with coordinated mechanisms of action.
The company said it will continue working with regulatory agencies to refine translational endpoints and human-relevant safety models for future IND submissions, positioning the NAMs-based approach as a template for its broader preclinical pipeline of bispecific antibodies and antibody-drug conjugates currently in discovery or IND-enabling stages.