

Up to $10 million debt financing supported by U.K. subsidiary VAT refunds and reimbursable R&D tax credits, including $5 million funded at the August 10, 2026 first closing FDA Type C Statistical Methods Meeting mid-September 2026 meeting to review 2.5-year Overall Survival data and confirmatory Phase 3 trial design to gain alignment on statistical analysis plan for BLA submission under the Accelerated Approval Program Interim 3-year Overall Survival data expected in early September 2026 ahead of MHRA Statistical Methods Scientific Advice Meeting for Conditional MAA submission acceptance criteria Final 3-year Overall Survival data to be included in FDA BLA Accelerated Approval Program submission ahead of Type B Pre-BLA Meeting previously granted in Q2/26 U.K. waives Pediatric Investigation Plan (PIP) requirement New York and Rockville, Maryland--(Newsfile Corp. - August 17, 2026) - OS Therapies, Inc. (NYSE American: OSTX) ("OS Therapies" or the "Company"), the world leader in gene-edited, Listeria-based cancer immunotherapies, today reported financial results for the second fiscal quarter ended June 30, 2026, and provided business and regulatory updates. The Company is seeking to obtain a Biologics License Application (BLA) under the Accelerated Approval Program of the U.S. Food & Drug Administration (FDA), and equivalent Conditional Marketing Accelerated Authorisations (CMAAs) from the Medicines and Healthcare products Regulatory Agency (MHRA) and European Medicines Agency (EMA), for OST-HER2 in the prevention or delay of recurrence in fully resected, pulmonary metastatic osteosarcoma (the "Metastatic Osteosarcoma Program").

Meeting to occur in mid-September 2026 Interim 3-year Overall Survival data expected early September, 2026 Decisions on appropriate comparator arm to interpret OST-HER2 clinical efficacy, RMAT designation and Rolling Review expected following this meeting Sustained overall survival benefit observed between 2-year and 2.5-year timepoints U.K. MHRA Statistical Methods Scientific Advice Meeting granted in parallel New York, New York and Rockville, Maryland--(Newsfile Corp. - August 13, 2026) - OS Therapies, Inc. (NYSE American: OSTX) ("OS Therapies" or "the Company"), the world leader in gene-edited, Listeria-based cancer immunotherapies, today announced that the U.S. Food and Drug Administration (FDA) has granted the Company's requested Type C Statistical Methods meeting to review the 2.5 year overall survival data from the Phase 2b trial of OST-HER2 in the prevention of recurrence in fully resected, pulmonary metastatic osteosarcoma (the "Metastatic Osteosarcoma Trial"). The Company expects the FDA Type C Statistical Methods Meeting to occur in mid-September 2026 with members from division within the Center for Biologics Evaluation and Research (CBER), in parallel with the pending Biomarker Data Review Meeting being scheduled with members of the Center for Drug Evaluation and Research's (CDER) Biomarker Qualification Program (BQP).

CDER meeting expected to take place in the summer of 2026 in parallel with CBER's Type B Statistical Methods Meeting New York, New York and Rockville, Maryland--(Newsfile Corp. - July 8, 2026) - OS Therapies, Inc. (NYSE American: OSTX) ("OS Therapies" or "the Company"), the world leader in gene-edited, Listeria-based cancer immunotherapies, today announced that it has accepted a new Meeting Request from the U.S. Food and Drug Administration (FDA)'s Center for Drug Evaluation and Research (CDER) to review the Company's pharmacodynamic response biomarker data (the "OST-HER2 Biomarker Data") – patent pending. CDER's Biomarkers, EndpointS, and other Tools (BEST) resources is part of its Biomarker Qualification Program (BQP).

Upcoming Type B Statistical Methods Meeting expected to set stage for FDA to align with EMA and MHRA on use of Fall 2026 3-year overall survival data combined with biomarkers to support early market access New York, New York and Rockville, Maryland--(Newsfile Corp. - July 6, 2026) - OS Therapies, Inc. (NYSE American: OSTX) ("OS Therapies" or "the Company"), the world leader in gene-edited, Listeria-based cancer immunotherapies, today provides a third quarter 2026 corporate outlook. The outlook focuses on upcoming clinical and regulatory milestones for the Company's lead program OST-HER2 in the prevention or delay of recurrence in fully resected, pulmonary metastatic osteosarcoma (the "Metastatic Osteosarcoma Program"), advancements with the Company's animal health-focused subsidiary OS Animal Health, Inc. (OSAH) and the Company's financial position as key regulatory and corporate milestones come into focus.

Company secures $10 million line of credit supported by OS Therapies UK tax credits New York, New York and Rockville, Maryland--(Newsfile Corp. - July 2, 2026) - OS Therapies, Inc. (NYSE American: OSTX) ("OS Therapies" or "the Company"), the world leader in gene-edited, Listeria-based cancer immunotherapies, today announced that it has appointed Dr. Craig Eagle to the Company's Board of Directors. Dr. Eagle currently serves as the Company's Chief Medical Advisor.

Type B Meeting requested to follow up on September 2025 End of Phase 2 FDA Meeting guidance on statistical methods to be used for BLA Submission Seeking to align FDA with MHRA & EMA on 3-year overall survival as approval endpoint Biomarker data submitted to FDA BEST program as surrogate clinical efficacy data Synthetic historical control arm OST-400 recruitment potentially adds comparator for BLA submission under the Accelerated Approval Review of Rolling Review, RMAT & Breakthrough Therapy designation requests sought New York, New York and Rockville, Maryland--(Newsfile Corp. - June 30, 2026) - OS Therapies, Inc. (NYSE American: OSTX) ("OS Therapies" or "the Company"), the world leader in gene-edited, Listeria-based cancer immunotherapies, today provided regulatory update on the Company's interactions with the U.S. Food and Drug Administration (FDA) in its pursuit of a Biologics License Application (BLA) under the Accelerated Approval Program (Accelerated Approval) for OST-HER2 in the prevention or delay of recurrence in fully resected, pulmonary metastatic osteosarcoma (the "Metastatic Osteosarcoma Program"). OS Therapies has requested a Type B Meeting to review the Company's 2.5-year overall survival data and to confirm alignment that 3-year overall survival data is an approvable clinical efficacy endpoint.

20% of OST-HER2 treated dogs survived 2-year vs. 1% in control group (p = 0.00995) Over 15,000 dogs per year diagnosed with osteosarcoma Company expects to submit U.S. Department of Agriculture meeting request to gain alignment on regulatory path towards conditional approval in the third quarter of 2026 OS Therapies reiterates plan to distribute OS Animal Health shares to shareholders OS Animal Health plans crowdfunding to expand shareholder base to meet U.S. national exchange initial listing standards, with indications of interest now being received Rockville, Maryland--(Newsfile Corp. - June 26, 2026) - OS Animal Health, Inc. ("OS Animal Health" or "the Company"), the wholly-owned animal health subsidiary of OS Therapies, Inc. (NYSE American: OSTX) ("OS Therapies"), the world leader in gene-edited, Listeria-based cancer immunotherapies, today announced the peer-reviewed publication of data from the Phase 2 clinical trial of OST-HER2, together with palliative radiation therapy ("RT"), aimed at preventing amputation in frontline canine osteosarcoma.

Confirmatory Phase 3 trial to commence prior to BLA grant under Accelerated Approval Program in the U.S. and Conditional MAA in the U.K., Europe and Australia Patent pending pharmacodynamic response biomarker accepted as surrogate clinical efficacy endpoint TGA and MHRA agree to allow utilization of remaining Phase 2b drug product for initiation of confirmatory Phase 3 FDA and EMA fully align with Company on Chemistry, Manufacturing and Controls (CMC) Market access process initiated with UK NICE and EU JCA New York, New York and Rockville, Maryland--(Newsfile Corp. - June 8, 2026) - OS Therapies, Inc. (NYSE American: OSTX) ("OS Therapies" or "the Company"), the world leader in gene-edited, Listeria-based cancer immunotherapies, today announced that it achieved alignment on the design of its pending Phase 3 study of OST-HER2 in the prevention or delay of recurrence in fully resected, pulmonary metastatic osteosarcoma with the U.S. Food & Drug Administration (FDA) and the U.K. Medicines and Healthcare products Regulatory Agency (MHRA). A confirmatory Phase 3 study is required to have commenced prior to the grant of a Biologics License Application (BLA) under the Accelerated Approval Program in the U.S. and Conditional Marketing Authorisation Applications (CMAAs) in the U.K., Europe and Australia.