New York, New York — November 25, 2025 — Leads & Copy — OS Therapies Inc. (NYSE American: OSTX) announced that the International Nonproprietary Names (INN) Expert Committee of the World Health Organization (WHO) has approved ‘daznelimgene lisbac’ as the non-proprietary name for its HER2 targeted Listeria monocytogenes-based cancer immunotherapy product candidate, OST-HER2.
OST-HER2 is currently under development for the prevention or delay of recurrent, fully resected, pulmonary metastatic osteosarcoma.
Each INN name is unique and used to identify active pharmaceutical ingredients. A unique name of worldwide acceptability must be granted to each active substance marketed as a pharmaceutical to ensure clear identification, safe prescription, and dispensing of medicines.
OS Therapies will transition towards using diznalimgene lisbac alongside OST-HER2 in future communications.
OS Therapies Chairman and CEO Paul Romness said the company is pleased to have completed this milestone on its path toward gaining regulatory approval for diznalimgene lisbac (formerly OST-HER2).
The company remains on track to get regulatory feedback from U.S., UK, and European regulatory authorities in December 2025 and file for regulatory approvals beginning in January 2026.
OS Therapies is focused on identifying, developing, and commercializing treatments for Osteosarcoma (OS) and other solid tumors. The company is the world leader in listeria-based cancer immunotherapies. OST-HER2, the company’s lead asset, is an immunotherapy leveraging the immune-stimulatory effects of Listeria bacteria to initiate a strong immune response targeting the HER2 protein.
OST-HER2 has received Rare Pediatric Disease Designation (RPDD) from the U.S. Food & Drug Administration and Fast-Track and Orphan Drug designations from the U.S. FDA and European Medicines Agency.
OS Therapies reported positive data in its Phase 2b clinical trial of OST-HER2 in recurrent, fully resected, lung metastatic osteosarcoma, demonstrating statistically significant benefit in the 12-month event free survival (EFS) primary endpoint of the study.
The company anticipates submitting a Biologics Licensing Application (BLA) to the U.S. FDA for OST-HER2 in osteosarcoma in early 2026 and if approved, would become eligible to receive a Priority Review Voucher that it could then sell.
OST-HER2 has completed a Phase 1 clinical study primarily in breast cancer patients and shown preclinical efficacy data in various models of breast cancer.
OST-HER2 has been conditionally approved by the U.S. Department of Agriculture for treating canines with osteosarcoma.
OS Therapies is advancing its next-generation Antibody Drug Conjugate (ADC) and Drug Conjugates (DC), known as tunable ADC (tADC), which features tunable, tailored antibody-linker-payload candidates. This platform leverages the company’s proprietary silicone Si-Linker and Conditionally Active Payload (CAP) technology, enabling the delivery of multiple payloads per linker.
Forward-looking statements in this press release are subject to certain risks and uncertainties detailed in the company’s most recent Annual Report on Form 10-K, most recent Quarterly Report on Form 10-Q, and other subsequent documents filed with the Securities and Exchange Commission.
Investor Relations Contact:Harrison Seidner, PhDWaterSeid PartnersOSTX@waterseid.com
Public Relations Contact:Stephanie ChenElev8 New Mediamedia@ostherapies.com
Source: OS Therapies
