OS Therapies reports three-year survival benefit in osteosarcoma study
OS Therapies reported final three-year survival data from its Phase 2b study of OST-HER2, also called Herlystic, in patients with resected pulmonary metastatic osteosarcoma. The company said treated patients had a 72.7 percent three-year overall survival rate, versus 45.8 percent in a combined published historical comparison group. OS Therapies said it is preparing early-access regulatory submissions in the U.S., U.K., Europe and Australia and plans to initiate a confirmatory Phase 3 trial.
Why it matters
The company says starting the Phase 3 trial is required before it can seek accelerated U.S. approval and conditional authorizations in other markets. The reported data could support those planned filings, but the survival comparison was against historical controls rather than a concurrent control group.
Key facts
- 1OS Therapies reported a 72.7 percent three-year overall survival rate for OST-HER2-treated patients, compared with 45.8 percent for the combined published historical control. finance.yahoo.com
- 2The company reported p = 0.0006 for the survival comparison. finance.yahoo.com
- 3The Phase 2b analysis included 41 total enrolled patients, with four patients lost to follow-up. finance.yahoo.com
- 4OS Therapies said it intends to complete U.S., European, U.K. and Australian regulatory submissions in the fourth quarter of 2026. finance.yahoo.com
- 5The company said Phase 3 initiation is a prerequisite for accelerated approval of a U.S. biologics license application. finance.yahoo.com
Open questions
- The reported survival comparison used a combined published historical control rather than a concurrent control group.
Summary written by AlphAI from 2 of 2 sources. Not investment advice. Figures are as stated by the linked sources.