Os Therapies (OSTX -1.26%), a clinical-stage biotechnology company focused on immunotherapies for rare pediatric cancers, released earnings for Q2 2025 on August 19, 2025. The most important news in the release highlighted continued progress toward regulatory milestones for its lead drug candidate, OST-HER2, alongside deepening financial losses. Net loss per share was $0.19. Reported EPS of $0.19 was below the analyst estimate of -$0.12 per share for Q2 2025. No revenue was recorded in the period, aligning with consensus, as Os Therapies remains pre-commercial. Operating losses were approximately 2.9 times higher than in the second quarter of 2024, driven by ramped-up regulatory and clinical activity. Overall, the quarter showcased major advances for OST-HER2’s potential approval but underscored the company’s persistent need for capital and ongoing expense escalation.
| Metric | Q2 2025 | Q2 2025 Estimate | Q2 2024 | Y/Y Change |
|---|---|---|---|---|
| EPS (GAAP) | $0.19 | ($0.12) | ($0.26) | N/A |
| Revenue (GAAP) | $0 | $0 | $0 | — |
| Operating Loss | $4.54 million | $1.56 million | (191.6 %) |
Source: Analyst estimates for the quarter provided by FactSet.
Company Overview and Business Focus
Os Therapies develops immunotherapies to address untreated or under-treated forms of cancer, with a core focus on pediatric osteosarcoma. The company’s lead asset, OST-HER2, is an immunotherapy. This drug candidate targets a rare bone cancer that has seen little innovation in four decades. The business pursues accelerated development for OST-HER2, leveraging multiple FDA special designations that support quick regulatory review and potential market exclusivity.
Recent efforts center on two main directions: advancing OST-HER2 through pivotal regulatory milestones in the U.S. and abroad, and strategically expanding intellectual property. Os Therapies also seeks to broaden its pipeline with the acquisition of clinical and preclinical immunotherapy assets and by developing new antibody-drug conjugate platforms for solid tumors. Success factors for the company hinge on positive trial data, regulatory achievements, strategic partnering, and effective commercialization strategy for its therapies.
Quarterly Results: Clinical Progress, Regulatory Milestones, and Financial Performance
Net loss per share was $0.19, which was below the analyst estimate of -$0.115, and Operating loss was $4.537 million for Q2 2025. This represents an increase of approximately 191.5% compared to the $1.557 million net operating loss in Q2 2024, highlighting a dramatic acceleration in spending. Management attributed this rise to escalating regulatory and clinical trial activities, particularly costs associated with advancing OST-HER2 through the pivotal Phase 2b trial and regulatory discussions with global agencies during Q2 2025.
On the clinical side, the Phase 2b trial for OST-HER2 produced several strong data points. Patients receiving OST-HER2 had a 12-month event-free survival rate of 35 %, while historical controls registered 20 %, with a p-value of 0.0197. Interim 2-year overall survival among treated patients reached 66.6 % (out of 27 patients) versus 40 % for controls (p = 0.0046) for updated interim 2-year overall survival data from the Phase 2b clinical trial of OST-HER2 in recurrent, fully resected, pulmonary metastatic osteosarcoma. No patients experienced serious (grade 4 or 5) treatment-associated side effects. These results provided momentum for further regulatory engagement and substantiated the safety profile of the therapy. Interim data was presented at the MIB Factor conference on June 28, 2025.
Regulatory progress was a defining element of the quarter. The U.S. Food and Drug Administration (FDA) confirmed that OST-HER2 meets the criteria for Regenerative Medicine Advanced Therapy designation, opening the path for expedited review. The FDA assigned a Biologics License Application (BLA) number, with an End of Phase 2 meeting scheduled for August 27, 2025, to finalize preparations for an Accelerated Approval submission. Internationally, the company submitted an Innovative Licensing and Access Pathway (ILAP) application to the UK regulator and requested a rapporteur meeting with the European Medicines Agency for October.
Os Therapies made several moves to position itself for future product launches and pipeline expansion. It announced a commercial partnership with Eversana to prepare for a potential U.S. launch of OST-HER2 in the first half of 2026 and began the necessary state licensing processes. The acquisition of Ayala Pharmaceuticals’ listeria immunotherapy platform brought in additional clinical-stage and preclinical programs alongside patent protection until 2040. The creation of subsidiaries—including OS Animal Health, aimed at veterinary applications of OST-HER2—expanded the company’s potential market and set the groundwork for broader commercial activities. The launch of OS Drug Conjugates underscores an ongoing focus on antibody-drug conjugate technology for various solid tumor indications.
Financing, Share Dilution, and Capital Markets Updates
Capital management remained a major focus for the quarter. The company completed a $4.2 million capital raise through warrant exercises shortly after period end. This transaction boosted Os Therapies’ cash reserves and provided management with a cash runway extending into mid-2026. Additionally, the company established an at-the-market equity sales agreement allowing up to $18 million in future fundraising, building financial flexibility at the cost of potential further dilution.
Management pointed investors to the potential sale of a priority review voucher, a special regulatory incentive that could be granted if OST-HER2 is approved by September 30, 2026. Recent sales of such vouchers ranged from $155 million to $160 million in May and June 2025, presenting a possible source of non-dilutive capital. Despite these developments, the immediate financial picture was one of continued losses and a reliance on capital markets as regulatory activities intensify. The company also gained inclusion in the Russell Microcap index, which may support liquidity and institutional investor interest.
Outlook and Investor Considerations
No formal guidance was provided for upcoming quarters or fiscal 2025. Management communicated that the current cash position, bolstered by recent fundraising, is expected to last through mid-2026. All forward-looking commentary centered on executing regulatory milestones, such as the BLA submission, FDA meeting dates, and international approvals for OST-HER2. Major upcoming events include the End of Phase 2 meeting with the FDA on August 27, 2025, a planned BLA submission in late Q3 2025, and critical decision points with UK and European authorities in the second half of the year.
With no revenue at this stage and an increasing burn rate, investors will be watching the progress of regulatory reviews and OST-HER2’s potential approval timeline, as well as any inflection points in non-dilutive funding such as a possible priority review voucher sale or business development deals. OSTX does not currently pay a dividend.
Revenue and net income presented using U.S. generally accepted accounting principles (GAAP) unless otherwise noted.
