OS Therapies shares surge 10.45% premarket after announcing 2026 regulatory milestones for OST-HER2, including FDA BLA and EU/UK MAA submissions, and JPMorgan data release.

OS Therapies Inc. (OSTX) surged 10.45% in premarket trading following the company’s announcement of its H1 2026 corporate outlook, which outlined key regulatory and clinical milestones for its lead candidate OST-HER2. The company confirmed plans to submit a U.S. FDA Biologics License Application (BLA) by end-January 2026 under the Accelerated Approval Program, alongside UK and EU Marketing Authorisation Applications (MAAs) by late February and March 2026, respectively. Additionally, the release of Phase 2b biomarker data during the J.P. Morgan Healthcare Conference 2026 and potential eligibility for a $160 million Priority Review Voucher if approved by September 2026 bolstered investor optimism. These developments, coupled with progress in veterinary oncology and pipeline expansion, underscored the company’s advancing regulatory and clinical strategy, driving the premarket rally.