OS Therapies Inc
OS Therapies Incorporated (NYSE: OSTX) is a clinical-stage biopharmaceutical company developing treatments for osteosarcoma and other solid tumors. Its lead candidate, OST-HER2, is an off-the-shelf immunotherapy made from an attenuated, genetically modified Listeria strain that expresses HER2 peptides and is intended… From the company’s description.
In fiscal 2025, OS Therapies Inc reported a net loss of $28.75M. Operations used $14.24M in cash.
Margins and return on equity change in ; everything else in percent. Fewer shares and less debt are shown plainly, not as bad news — it depends what you make of buybacks. Dotted labels explain each measure. is shown separately from the annual figures.
What OS Therapies Inc does
In the company’s own words
OS Therapies Incorporated (NYSE: OSTX) is a clinical-stage biopharmaceutical company developing treatments for osteosarcoma and other solid tumors. Its lead candidate, OST-HER2, is an off-the-shelf immunotherapy made from an attenuated, genetically modified Listeria strain that expresses HER2 peptides and is intended to stimulate an immune response against cancer. The company’s Phase IIb study evaluated OST-HER2 in patients after surgery for recurrent pulmonary metastatic osteosarcoma and enrolled 41 patients. Its second technology, OST-tADC, is a preclinical antibody-drug conjugate platform using pH-sensitive silicon linkers to deliver payloads to tumors; its lead program targets folate receptor alpha, which is overexpressed in several cancers. OS Therapies acquired HER2-related assets from Ayala Pharmaceuticals in 2025, including investigational programs for non-small cell lung and prostate cancers. The company has no approved commercial products and relies on third parties for manufacturing. Its website is www.ostherapies.com.
Company details
- Sector
- Health Care
- Industry (SIC)
- Pharmaceutical Preparations
- Headquarters
- ROCKVILLE, MD
- Fiscal year end
- December
- CIK
- 1795091
- SIC
- 2834
Financial performance, year by year
Fiscal 2024–2025 · USDThe full income statement, balance sheet and cash flow for each of these years — every figure traceable to its filing — is on the Financials tab with a free account.
Who owns OS Therapies Inc — and what changed
Funds as of 2026Q2 · superinvestors as of 2026-06-30
Largest fund holders · OS Therapies Inc’s weight in each
Fund ownership is a floor, not a census — pensions, insurers and people holding shares directly are not visible here.
Fund ownership counts N-PORT filers only, so it is a floor rather than a census — pensions, insurers and direct holders are not visible here, and the remainder is not “held by individuals”.
Could not be determined for this company: bond issues.
Every fund and institutional holder, quarter by quarter, is on the Ownership tab with a free account.
Recent filings
All filings →Each filing opens into its own statements and disclosures here.
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