Core Insights - OS Therapies has received a second Type C Meeting from the FDA to discuss clinical efficacy data endpoints for OST-HER2, aimed at supporting a Biologics Licensing Application under the Accelerated Approval Program following a successful Phase 2b trial for metastatic osteosarcoma [1][2] - The UK MHRA has granted a pre-MAA Meeting for the same program, with the company planning to align BLA and MAA submission timelines as part of Project Orbis [2] - The company reported positive results from its Phase 2b clinical trial, demonstrating statistically significant benefits in the 12-month event-free survival primary endpoint [6] Company Overview - OS Therapies is a clinical-stage oncology company focused on developing treatments for osteosarcoma and other solid tumors, with its lead asset OST-HER2 being an immunotherapy targeting the HER2 protein [4][6] - OST-HER2 has received multiple designations from regulatory agencies, including Rare Pediatric Disease Designation and Fast-Track status from the FDA [4] - The company is also advancing its next-generation Antibody Drug Conjugate (ADC) platform, known as tunable ADC (tADC), which utilizes proprietary technology for enhanced drug delivery [7] Clinical Development and Regulatory Strategy - The FDA meeting is scheduled for December 11, 2025, allowing time for the company to gather biomarker data to correlate immune activation with clinical outcomes [1][5] - The recent FDA/Osteosarcoma Institute Workshop emphasized the importance of overall survival data as a key efficacy endpoint and discussed appropriate clinical trial designs for future immunotherapies [3][5] - The company anticipates submitting a BLA for OST-HER2 in 2025, which, if approved, would make it eligible for a Priority Review Voucher [6]