OS Therapies Submits OST-HER2 BLA Modules, Eyes Q3 Trial and $200M PRV
OS Therapies submitted CMC BLA modules for OST-HER2 to the FDA in January 2026 and plans to file its Clinical BLA after a March meeting, with MHRA and EMA MAA submissions by end-Q1 2026. Expects Q1 biomarker data, Q3 confirmatory trial for a $200 million PRV and Ayala’s 4.8 million share liquidation.
1. Regulatory Progress
OS Therapies submitted Non-Clinical and CMC modules of its OST-HER2 Biologics License Application (BLA) to the FDA at the end of January 2026. The company plans to file the Clinical BLA module after a Type D meeting with the FDA in March and anticipates submitting conditional Marketing Authorisation Applications to the MHRA and EMA by the end of Q1 2026.
2. Biomarker Data and Trial Plans
Additional biomarker analyses from the Human Metastatic Osteosarcoma Program are expected in Q1 2026 to characterize immune pathway activation and its relationship to clinical outcomes. OS Therapies intends to initiate a confirmatory trial under the Accelerated Approval statute in Q3 2026, opening a single site initially to satisfy regulatory requirements before broader activation.
3. Ayala Liquidation and PRV Opportunity
OST-HER2 holds FDA Orphan Drug, Fast Track and Rare Pediatric Disease designations, making OS Therapies eligible for a Priority Review Voucher upon accelerated U.S. approval, with recent PRV sales at roughly $200 million. Ayala Pharmaceuticals completed liquidation of its 4.8 million OS Therapies shares on February 9, 2026, removing a notable overhang on the share register.