Core Insights - OS Therapies received a positive regulatory update from the European Medicines Agency (EMA) following a meeting with the Dutch Medicines Evaluation Board (MEB) on October 6, 2025, regarding its OST-HER2 Phase 2b clinical trial for osteosarcoma [2][3] Regulatory Developments - The meeting aligned on key areas such as safety, non-clinical data, and chemistry, manufacturing, and controls (CMC) data, supporting the ongoing clinical trial [3][8] - The overall survival results from the trial, showing statistically significant final two-year data, may serve as a primary endpoint for conditional marketing authorization (CMA) [3][8] - A formal EMA Scientific Advice is anticipated in December 2025, establishing a potential pathway for a confirmatory randomized clinical development program [4][10] Clinical Trial Insights - The safety profile from the Fully Resected Osteosarcoma clinical study was confirmed as positive, with data from over 500 patients treated across four other therapeutic indications potentially supporting a CMA [8] - The rapporteur indicated that overall survival (OS) could provide a stronger measure of clinical benefit compared to 12-month Event-Free Survival (EFS) [8] - Efficacy data from other settings, such as recurrent, unresectable pulmonary metastatic osteosarcoma, could be incorporated into a post-market confirmatory clinical development program [8] Market Access and Future Plans - OS Therapies has commenced the Marketing Authorisation Application (MAA) submissions process with the UK MHRA, which has granted an expedited Market Access Scientific Advice Meeting [6] - The company plans to pursue a conditional marketing authorization while advancing a global randomized clinical study to evaluate OST-HER2 in various osteosarcoma clinical settings [10] - OST-HER2 has received multiple designations from the U.S. FDA and EMA, including Rare Pediatric Disease Designation and Fast-Track status [11]