Stonegate Capital Partners Updates Coverage on OS Therapies Inc. (OSTX) 3Q25

Rhea-AI Summary

OS Therapies (NYSE American: OSTX) advanced clinical, regulatory, and commercial milestones in 3Q25 for OST-HER2 in recurrent, fully resected pulmonary metastatic osteosarcoma.

Key facts: a 41-patient Phase 2b showed 2-year overall survival 75% versus 40% historical control and 100% 2-year survival for patients event-free at 12 months. Management targets UK pre-MAA in December and FDA Type C then filings in January 2026, expects PRV monetization in 2026 and commercial OST-HER2 revenues in early 2027. The company plans a 1H26 spinoff of OS Animal Health with direct equity to OSTX shareholders. Quarter-end cash was ~$1.9M with a $6.9M net loss; post-quarter proceeds of $7.8M plus an ATM extend runway into late 2026.

Positive

• Phase 2b 2-year OS 75% vs 40% historical
• 100% 2-year survival if event-free at 12 months
• Regulatory filings targeted: UK pre-MAA Dec 2025 and FDA filings Jan 2026
• PRV monetization expected in 2026 and commercial revenues early 2027
• Planned 1H26 spinoff of OS Animal Health gives direct equity to OSTX shareholders

Negative

• Quarter-end cash ~$1.9M with a $6.9M net loss
• Commercial OST-HER2 revenues are not expected until early 2027

Insights

Clinical/Regulatory Strategist

Phase 2b survival data and targeted regulatory filings materially advance OST-HER2 toward approval and market entry.

OST-HER2 showed a 75% 2-year overall survival rate in a 41-patient Phase 2b trial versus 40% historical controls, and 100% 2-year survival for patients event-free at 12 months, which supports a durable clinical signal in this specific population.

Management plans harmonized U.S./ex-U.S. filings with a UK pre-MAA in December and an FDA Type C on December 11, then filing targeted for January 2026. These are concrete, short-term regulatory milestones that materially affect approval timing and deserve close tracking.

Watch the regulatory docket through January 2026 for submission confirmations, any FDA/MHRA meeting minutes, and formal PRV eligibility documentation in 2026. These items will be the fastest indicators of near-term clinical-to-approval translation.

Corporate Finance & Commercialization

Spin-off, PRV timing, and updated cash provide clearer financing and commercial timing for OSTX and its franchise.

The company expects initial PRV monetization in 2026 and commercial OST-HER2 revenues beginning in early 2027, and announced an intent to spin off OS Animal Health as a standalone public company in 1H26 with OSTX shareholders receiving direct equity.

Quarter end cash was approximately $1.9M with a net loss of $6.9M, and post-quarter proceeds of $7.8M from warrants plus an ATM that management says extends runway into late 2026. Monitor cash runway updates, PRV monetization timing, and the structure/timing of the 1H26 spinoff for their impact on dilution and funding.

Dallas, Texas--(Newsfile Corp. - November 21, 2025) - OS Therapies Inc. (NYSE American: OSTX): Stonegate Capital Partners updates their coverage on OS Therapies Inc. (NYSE American: OSTX). OS Therapies advanced key clinical, regulatory, and commercial milestones in 3Q25 as it moves closer to bringing OST-HER2 to patients with recurrent, fully resected, pulmonary metastatic osteosarcoma. Final 2-year OS data from the 41-patient Phase 2b trial showed a 2-year OS rate of 75% for OST-HER2 vs 40% in historical controls, with 100% 2-year survival among patients event-free at 12 months, reinforcing durable benefit. Building on a successful End-of-Phase 2 interaction, management is preparing harmonized U.S./ex-U.S. filings with UK MHRA and FDA submissions expected around year-end, supported by its Eversana partnership and a launch plan that anticipates initial PRV monetization in 2026 and commercial OST-HER2 revenues beginning in early 2027. Subsequent to quarter-end, the Company also announced its intent to spin off OS Animal Health (OSAH) into a separately financed, standalone public company in 1H26, with OSTX shareholders expected to receive direct equity participation in the new listing.

To view the full announcement, including downloadable images, bios, and more, click here.

Key Takeaways:

• Regulatory path on track with UK pre MAA in December and FDA Type C on December 11 filings targeted for January 2026 supported by Phase 2b showing 2 year OS 75% vs 40% and PRV eligibility in 2026.
• Planned spinoff of OS Animal Health in 1H26 gives shareholders direct equity and advances the canine OST HER2 franchise.
• Quarter ended with ~$1.9M cash, net loss $6.9M and post quarter $7.8M warrant proceeds and ATM in place extending runway into late 2026.

Click image above to view full announcement.

---

About Stonegate
Stonegate Capital Partners is a leading capital markets advisory firm providing investor relations, equity research, and institutional investor outreach services for public companies. Our affiliate, Stonegate Capital Markets (member FINRA) provides a full spectrum of investment banking services for public and private companies.

Contacts:

Stonegate Capital Partners
(214) 987-4121
info@stonegateinc.com

Source: Stonegate, Inc.

To view the source version of this press release, please visit https://www.newsfilecorp.com/release/275571

FAQ

What did OS Therapies (OSTX) report from its Phase 2b trial in 3Q25?

The 41-patient Phase 2b reported a 2-year OS of 75% versus 40% historical control and 100% 2-year survival among patients event-free at 12 months.

When does OSTX plan regulatory filings for OST-HER2 with the FDA and MHRA?

Management is targeting a UK pre-MAA in December 2025 and filings with the FDA around January 2026 after a Type C interaction.

What is OSTX's timetable for PRV monetization and commercial OST-HER2 revenue?

The company expects PRV monetization in 2026 and commercial OST-HER2 revenues beginning in early 2027.

What are the financial runway details reported by OSTX in 3Q25?

Quarter-end cash was approximately $1.9M with a $6.9M net loss; post-quarter $7.8M in warrant proceeds plus an ATM are expected to extend runway into late 2026.

How will the planned 1H26 spinoff of OS Animal Health affect OSTX shareholders?

The company plans a 1H26 spinoff of OS Animal Health where OSTX shareholders are expected to receive direct equity participation in the new public listing.