OS Therapies Phase III Survival Data Beats Historical Controls

OS Therapies, Inc. reported Tuesday interim three-year overall survival data from its ongoing Phase 2b clinical evaluation.

The study, called the metastatic osteosarcoma program, is designed to test whether OST-HER2 prevents or delays disease recurrence in patients with resected lung metastases from osteosarcoma.

Osteosarcoma is the most common primary malignant bone cancer, arising from cells that form new bone tissue.

The company emphasized that patients treated with OST-HER2 achieved a statistically significant benefit compared to a pooled historical control group used for regulatory discussions.

Interim Phase 2b Survival Rates Surpass Historical Benchmarks

The interim analysis showed that patients treated with OST-HER2 reached a 71.2% three-year overall survival rate.

In comparison, the corresponding pooled historical control group had a lower three-year overall survival rate of 45.8%.

Currently, only two study participants have not yet reached the three-year time point following initial enrollment.

OS Therapies has scheduled clinical monitoring visits for these two remaining patients in September 2026 and early October 2026.

See more:

Top value stocks

Global Phase 3 Expansion Capital Allocation Strategy

Alongside the survival data release, the company reported that it had received a $3.15 million VAT refund through its wholly owned subsidiary, OS Therapies U.K., Ltd.

Receipt of these funds confirmed the subsidiary's eligibility for an additional VAT and R&D tax credit of at least $7.2 million.

The company has earmarked these tax credit funds for launching a confirmatory Phase 3 clinical trial in the UK.

That trial is a critical step for OS Therapies to qualify for a Biologics License Application through the FDA's accelerated approval pathway.

Additionally, the clinical trial will support submissions for conditional marketing authorization in the UK, Europe, and Australia.

OS Therapies Stock Performance

OSTX stock price movement: At Tuesday's release, OS Therapies shares fell 3.72% to $1.81.