OS THERAPIES INCORPORATED Stock Price, News & Analysis

OS Therapies (NYSE American: OSTX) announced significant regulatory progress for its oncology programs. The company has scheduled an End of Phase 2 Meeting with FDA on August 27, 2025 to review its OST-HER2 program for recurrent, pulmonary metastatic osteosarcoma, aiming to begin a rolling BLA submission under Accelerated Approval.

The company has secured Scientific Advice Meetings with European regulators, including EMA and MHRA, pursuing marketing authorizations across Europe and the UK. Additionally, all patients in the Phase 1 clinical study of OST-504 for second-line prostate cancer have completed treatment, with data expected in H2 2025.

OS Therapies aims to obtain regulatory approval for OST-HER2 before the rare pediatric disease priority review voucher (PRV) program expires, planning to use potential PRV sale proceeds for commercialization and pipeline advancement.

OS Therapies (NYSE-A: OSTX) has achieved a significant milestone as the FDA granted an End of Phase 2 Meeting for its OST-HER2 program, targeting the prevention of recurrent, fully resected, pulmonary metastatic osteosarcoma. The meeting is scheduled for Q3 2025.

The company plans to pursue a Rolling Review process for its Biologics Licensing Application (BLA), potentially expediting the approval timeline. OST-HER2 has secured multiple FDA designations including Orphan Disease, Fast Track, and Rare Pediatric Disease Designation. If granted Accelerated Approval before September 30, 2026, OSTX could receive a Priority Review Voucher, with recent vouchers valued at $160 million.

OST-HER2 is an immunotherapy using HER2-bioengineered Listeria monocytogenes to target HER2-expressing cancer cells, with ongoing development in both human and canine applications.

OS Therapies (NYSE-A: OSTX) announced statistically significant positive clinical data for its immunotherapy candidate OST-HER2 in treating osteosarcoma. The Phase 2b trial showed that 35% of OST-HER2-treated patients achieved 1-year event free survival (EFS) compared to 20% in the historical control group (p=0.0194).

The safety profile demonstrated that 13 out of 40 patients experienced severe adverse events (SAEs), with only 7 patients having treatment-associated adverse events (TSAEs), all grade 3, with no grade 4 or 5 events reported. Notably, no patients discontinued the study due to adverse events.

The company is pursuing FDA Accelerated Approval and has submitted additional external control data following a Type D Meeting. OST-HER2 holds multiple FDA designations including Orphan Disease Designation, Fast Track, and Rare Pediatric Disease Designation. The UK's MHRA has agreed to support the company with data from its Clinical Practice Research Datalink to assist in potential worldwide marketing authorizations.

OS Therapies (NYSE-A: OSTX) received positive FDA feedback regarding its Phase 2b trial of OST-HER2, an immunotherapy treatment for preventing recurrence in pediatric lung metastatic osteosarcoma. The company has submitted requests for an End of Phase 2 Meeting and Breakthrough Therapy Designation (BTD), with the meeting expected in Q3 2025.

OST-HER2 has received Rare Pediatric Disease Designation and could be eligible for a Priority Review Voucher worth approximately $160 million if granted conditional BLA via Accelerated Review before September 2026. The osteosarcoma treatment market is valued at $1.2 billion, with the company estimating OST-HER2's market opportunity at over $500 million.

OS Therapies (NYSE-A: OSTX) has announced a warrant exercise inducement and exchange offer for holders of its five-year warrants originally issued in December 2024. Current warrant holders can exercise their $1.12 warrants in exchange for new five-year warrants with a $3.00 exercise price.

The exercise of all Old Warrants would provide ~$8 million in gross proceeds, with $1.76 million already received, extending cash runway into H2 2026. The New Warrants include a forced exercise provision at $9.00 per share. The offer period runs from June 20 to July 10, 2025.

The company plans to submit a Biologics Licensing Application (BLA) for OST-HER2 in Q3 2025 and will present additional Phase 2b trial data on June 28, 2025. If approved before September 2026, the company could receive a Priority Review Voucher, recently valued at $160 million.

OS Therapies (NYSE-A: OSTX) has partnered with EVERSANA to commercialize OST-HER2, a groundbreaking immunotherapy for pediatric lung metastatic osteosarcoma. OST-HER2 is the first potential new treatment in over 40 years for this rare and aggressive bone cancer. The therapy has received multiple FDA designations including Orphan, Fast Track, and Rare Pediatric Disease. A Biologics License Application rolling submission is planned for Q3 2025, with potential approval by year-end. EVERSANA will provide comprehensive commercialization services through its ONCOLOGY model, including market access, medical affairs, and patient services. OS Therapies recently secured U.S. Patent #12,239,738, providing manufacturing exclusivity for OST-HER2 and its Listeria-based platform through 2040.

OS Therapies (NYSE-A: OSTX) has submitted a request for Regenerative Medicine Advanced Therapy (RMAT) Designation to the FDA for OST-HER2, targeting the prevention of metastases in recurrent, fully-resected, lung metastatic pediatric osteosarcoma. If granted, OST-HER2 would be the first listeria investigational medicinal product with RMAT designation. The therapy already holds Rare Pediatric Disease, Orphan Drug, and Fast Track Designations. If OST-HER2 receives conditional BLA via Accelerated Review before September 2026, the company could receive a Priority Review Voucher worth potentially $155 million based on recent sales. OS Therapies expects FDA feedback by mid-June 2025 and plans to request an End of Phase 2 meeting to begin BLA submission in Q3 2025. The company is also pursuing European and UK market access through EMA PRIME Designation and CMA applications.

OS Therapies (NYSE-A: OSTX) reported Q1 2025 financial results and provided key business updates. The company reported a net loss of $3.876 million ($0.18 per share) compared to $1.490 million ($0.25 per share) in Q1 2024. Key highlights include:

The company announced positive data from its OST-HER2 Phase 2b clinical trial for preventing recurrent, fully resected, lung metastatic pediatric osteosarcoma. OS Therapies expects FDA feedback by mid-June 2025 regarding statistical analysis methods for pending Accelerated Approval.

Notable achievements include acquiring the listeria immunotherapy platform from Ayala Pharmaceuticals, adding three clinical stage and eight preclinical assets. A new manufacturing patent extends exclusivity protection until 2040. The company remains on track for Q3 2025 BLA filing for OST-HER2 and has sufficient funds to operate into mid-2026.

OS Therapies (NYSE-A: OSTX) has announced the formation of OS Animal Health, a subsidiary focused on commercializing OST-HER2 for canine osteosarcoma treatment. The market opportunity for OST-HER2 in canine osteosarcoma exceeds $150 million. The subsidiary will operate independently with separate funding to target the veterinary market. Recent data shows OST-HER2's effectiveness in preventing amputation and controlling metastatic osteosarcoma. The company plans to submit for USDA conditional approval in H2 2025, while the parent company targets FDA Accelerated Approval for pediatric osteosarcoma in Q3 2025. Osteosarcoma affects over 40,000 dogs annually in the U.S., representing 86% of the $1.57 billion veterinary oncology market. A new patent protects OST-HER2's commercial manufacturing process until 2040, and revenue generation is expected to begin in 2025.