STRO-227

STRO-227 is a dual-payload antibody-drug conjugate (ADC) being developed by Sutro Biopharma for the treatment of solid tumors. It is designed to target Protein Tyrosine Kinase 7 (PTK7), a cell surface protein overexpressed in various cancers including lung, breast, and ovarian. STRO-227 is the first dual-payload candidate from Sutro's proprietary XpressCF+ cell-free protein synthesis platform, which enables precise, site-specific conjugation of multiple distinct payloads to a single antibody. This approach is intended to enhance therapeutic efficacy and overcome resistance mechanisms by delivering two different cytotoxic agents directly to the tumor cells. The company plans to submit an Investigational New Drug (IND) application for STRO-227 in the 2026-2027 timeframe.