OS Therapies Announces Positive Data for OST-HER2 in the Treatment of Unresected Osteosarcoma in Dogs Opening the Potential for Use as Front-Line Therapy in Humans
OS Therapies (NYSE: OSTX) announced positive data for their OST-HER2 treatment in canine osteosarcoma, showing promising results for potential human applications. The study demonstrated that combining OST-HER2 with palliative radiation in dogs with unresected osteosarcoma led to tumor arrest and extended survival of over 500 days in 5 out of 15 dogs.
A new publication in Molecular Therapy revealed that OST-HER2 induces strong immune responses from the first dose, correlating with metastasis prevention and long-term survival in dogs with resected osteosarcoma. The treatment was well-tolerated in both studies, suggesting potential for progression-free survival of primary osteosarcoma and prevention of metastatic disease.
The company plans to submit data to USDA for conditional approval of their new manufacturing process, aiming to begin sales in 2025, with full approval targeted for 2026. OS Therapies is pursuing Accelerated Approval for OST-HER2 in human osteosarcoma by year-end 2025.
OS Therapies (NYSE: OSTX) ha annunciato dati positivi per il loro trattamento OST-HER2 nell'osteosarcoma canino, mostrando risultati promettenti per potenziali applicazioni umane. Lo studio ha dimostrato che combinare OST-HER2 con radioterapia palliativa in cani con osteosarcoma non resecato ha portato a un arresto del tumore e a un prolungamento della sopravvivenza di oltre 500 giorni in 5 su 15 cani.
Una nuova pubblicazione su Molecular Therapy ha rivelato che OST-HER2 induce forti risposte immunitarie già dalla prima dose, correlando con la prevenzione delle metastasi e la sopravvivenza a lungo termine nei cani con osteosarcoma resecato. Il trattamento è stato ben tollerato in entrambi gli studi, suggerendo un potenziale per la sopravvivenza senza progressione dell'osteosarcoma primario e la prevenzione della malattia metastatica.
L'azienda prevede di presentare dati al USDA per l'approvazione condizionata del loro nuovo processo di produzione, con l'obiettivo di iniziare le vendite nel 2025 e di ottenere l'approvazione completa entro il 2026. OS Therapies sta perseguendo l'Approccio Accelerato per OST-HER2 nell'osteosarcoma umano entro la fine del 2025.
OS Therapies (NYSE: OSTX) anunció datos positivos para su tratamiento OST-HER2 en osteosarcoma canino, mostrando resultados prometedores para aplicaciones humanas potenciales. El estudio demostró que combinar OST-HER2 con radiación paliativa en perros con osteosarcoma no resecado condujo a la detención del tumor y a una supervivencia prolongada de más de 500 días en 5 de 15 perros.
Una nueva publicación en Molecular Therapy reveló que OST-HER2 induce respuestas inmunitarias fuertes desde la primera dosis, correlacionándose con la prevención de metástasis y la supervivencia a largo plazo en perros con osteosarcoma resecado. El tratamiento fue bien tolerado en ambos estudios, sugiriendo un potencial para la supervivencia libre de progresión del osteosarcoma primario y la prevención de la enfermedad metastásica.
La empresa planea presentar datos al USDA para la aprobación condicional de su nuevo proceso de fabricación, con el objetivo de comenzar las ventas en 2025, y la aprobación completa prevista para 2026. OS Therapies está buscando la Aprobación Acelerada para OST-HER2 en osteosarcoma humano para finales de 2025.
OS Therapies (NYSE: OSTX)는 개 골육종 치료제 OST-HER2에 대한 긍정적인 데이터를 발표하며, 인간 응용 가능성에 대한 유망한 결과를 보여주었습니다. 연구에 따르면, 수술이 불가능한 골육종을 가진 개에서 OST-HER2와 완화 방사선을 결합하면 종양이 정지되고 15마리 중 5마리에서 500일 이상의 생존 기간이 연장된 것으로 나타났습니다.
Molecular Therapy에 발표된 새로운 연구에서는 OST-HER2가 첫 번째 투여부터 강력한 면역 반응을 유도하여, 수술이 가능한 골육종을 가진 개에서 전이 예방 및 장기 생존과 관련이 있음을 밝혔습니다. 이 치료는 두 연구 모두에서 잘 견디었으며, 이는 진행 없는 생존의 잠재력과 전이성 질병 예방 가능성을 시사합니다.
회사는 새로운 제조 공정에 대한 조건부 승인을 위해 USDA에 데이터를 제출할 계획이며, 2025년부터 판매를 시작할 목표를 가지고 있으며, 2026년에는 완전 승인을 목표로 하고 있습니다. OS Therapies는 2025년 말까지 인간 골육종에 대한 OST-HER2의 가속 승인을 추진하고 있습니다.
OS Therapies (NYSE: OSTX) a annoncé des données positives pour leur traitement OST-HER2 dans l'ostéosarcome canin, montrant des résultats prometteurs pour des applications humaines potentielles. L'étude a démontré que la combinaison d'OST-HER2 avec une radiothérapie palliative chez des chiens atteints d'ostéosarcome non résécable a conduit à l'arrêt de la tumeur et à une survie prolongée de plus de 500 jours chez 5 des 15 chiens.
Une nouvelle publication dans Molecular Therapy a révélé qu'OST-HER2 induit de fortes réponses immunitaires dès la première dose, corrélant avec la prévention des métastases et la survie à long terme chez les chiens ayant subi une résection de l'ostéosarcome. Le traitement a été bien toléré dans les deux études, suggérant un potentiel pour la survie sans progression de l'ostéosarcome primaire et la prévention de la maladie métastatique.
L'entreprise prévoit de soumettre des données à l'USDA pour une approbation conditionnelle de son nouveau processus de fabrication, visant à commencer les ventes en 2025, avec une approbation complète prévue pour 2026. OS Therapies cherche à obtenir une approbation accélérée pour OST-HER2 dans l'ostéosarcome humain d'ici la fin de 2025.
OS Therapies (NYSE: OSTX) gab positive Daten zu ihrer OST-HER2-Behandlung bei canine Osteosarkomen bekannt, die vielversprechende Ergebnisse für potenzielle Anwendungen beim Menschen zeigen. Die Studie zeigte, dass die Kombination von OST-HER2 mit palliativer Strahlentherapie bei Hunden mit nicht resezierbarem Osteosarkom zu einem Tumorstillstand und einer verlängerten Überlebensdauer von über 500 Tagen bei 5 von 15 Hunden führte.
Eine neue Veröffentlichung in Molecular Therapy zeigte, dass OST-HER2 bereits ab der ersten Dosis starke Immunantworten induziert, die mit der Metastasenprävention und der langfristigen Überlebensfähigkeit bei Hunden mit reseziertem Osteosarkom korrelieren. Die Behandlung wurde in beiden Studien gut vertragen, was auf ein Potenzial für progressionsfreies Überleben des primären Osteosarkoms und die Prävention von metastatischer Erkrankung hinweist.
Das Unternehmen plant, Daten beim USDA zur bedingten Genehmigung ihres neuen Herstellungsprozesses einzureichen, mit dem Ziel, 2025 mit dem Verkauf zu beginnen, während die vollständige Genehmigung für 2026 angestrebt wird. OS Therapies strebt bis Ende 2025 eine beschleunigte Genehmigung für OST-HER2 bei menschlichem Osteosarkom an.
- Strong efficacy data with 33% of dogs showing extended survival over 500 days
- Treatment demonstrates potential to reduce/delay need for amputation and chemotherapy
- Well-tolerated safety profile in multiple studies
- New patented manufacturing process developed
- Potential for multiple revenue streams (veterinary and human applications)
- Full approval not expected until 2026 for veterinary use
- Human treatment approval still pending and uncertain
- sample size in dog study (15 subjects)
- Current manufacturing process described as suboptimal for widespread veterinary use
Insights
The OST-HER2 data represents a potentially significant advancement in osteosarcoma treatment. The combined approach with palliative radiation showed tumor arrest and prolonged survival of >500 days in 33% of dogs with unresected osteosarcoma, without requiring surgery or chemotherapy. This is remarkable since osteosarcoma typically necessitates amputation with a poor prognosis otherwise.
The immunological mechanism demonstrated in the Molecular Therapy publication is particularly compelling - OST-HER2 induces both innate and cytotoxic immune responses from the very first dose. The correlation between these immune responses and prevention of metastasis is crucial, as metastatic disease is the primary cause of mortality in osteosarcoma patients. The observation that short-term survivors had defective immune responses that improved with subsequent doses suggests a recurrent dosing regimen could significantly alter clinical outcomes.
From a translational perspective, the 96% genetic homology between canine and human osteosarcoma strengthens the potential application to human patients. If these results translate to humans, OST-HER2 could revolutionize the standard of care by potentially reducing the need for aggressive interventions like amputation and toxic chemotherapy regimens. The data supports OST-HER2's potential across multiple treatment stages – from primary disease to metastatic prevention and management – representing a comprehensive therapeutic approach for this challenging malignancy.
OS Therapies' announcement represents a substantial pipeline expansion opportunity that significantly enhances OSTX's market potential. The new data effectively positions OST-HER2 across the entire osteosarcoma treatment paradigm rather than just in the recurrent metastatic setting, substantially enlarging its addressable market.
The dual-market strategy is particularly noteworthy. The company aims to secure USDA conditional approval for veterinary use in 2025, followed by full approval in 2026, creating a near-term revenue stream. Simultaneously, they're pursuing Accelerated Approval for human use by year-end 2025, potentially generating a Priority Review Voucher (PRV) that could be sold for
This strategic approach allows OSTX to fund expanded human clinical trials using PRV sale proceeds, without dilutive financing. The company's timeline appears ambitious but achievable given the strong data package and the FDA's openness to accelerated pathways for rare pediatric diseases. The proven safety profile and efficacy signals across multiple canine studies further de-risk the regulatory pathway.
For a company with a market cap of approximately
Yet to be published data from clinical study combining OST-HER2 with palliative radiation in dogs with unresected, primary osteosarcoma shows clinical and radiographic arrest of the primary tumor, delayed pulmonary metastases and prolonged overall survival of greater than 500 days in 5 out of 15 dogs.
Data from new publication in the journal "Molecular Therapy" show OST-HER2 induces strong innate and cytotoxic immune responses beginning at the 1st dose of 3 dose regimen, that correlate with prevention of metastasis and long-term survival in dogs with resected primary osteosarcoma.
Data from the same study show that short-term survivors have defective immune responses to OST-HER2 that improve with the second and third administration, supporting a proposed regimen of recurrent dosing to potentially alter clinical course and repeated use after treatment failure
New York, New York--(Newsfile Corp. - April 10, 2025) - OS Therapies (NYSE American: OSTX) ("OS Therapies" or "the Company"), a clinical-stage immunotherapy and Antibody Drug Conjugate (ADC) biopharmaceutical company, today announced positive data in the prevention or delay of amputation during the treatment of primary osteosarcoma for OST-HER2 combined palliative radiation in dogs with unresected appendicular osteosarcoma. The treatment led to clinical and radiographic arrest of the primary tumor and prolonged time to metastasis in dogs without surgery or chemotherapy. The data open the potential for OST-HER2 to be used in frontline therapy in human osteosarcoma prior to initiation of chemotherapy, and potentially reduce the need for chemotherapy altogether, for the purposes of preventing or delaying limb amputation or primary tumor resection surgeries, in addition to the prevention, delay and/or control of lung metastasis.
Additionally, the Company announced the publication of positive data in the journal "Molecular Therapy" entitled "Immunological responses and clinical outcomes in dogs with osteosarcoma receiving standard therapy and a Listeria vaccine expressing HER2" demonstrated the correlation of innate and adaptive immune responses to OST-HER2, with prevention of metastasis and long term survival benefit when used in the adjuvant setting, following standard of care amputation and chemotherapy.
Treatment with OST-HER2 was found to be safe and well tolerated in both studies.
Taken together, the data support the potential of OST-HER2 to achieve progression free survival (PFS) of primary osteosarcoma, prevent or delay or metastatic disease, prolong progression free survival (PFS) in metastatic disease, and significantly improve long term survival in patients with osteosarcoma. The data on the use of OST-HER2 in unresected primary osteosarcoma in dogs is being prepared for peer-reviewed publication.
"We first published strong clinical data on the benefit of OST-HER2 in canine osteosarcoma in 2016, and that led to an initial conditional approval based on a prior manufacturing process that was suboptimal for widespread veterinary use," said Dr. Nicola Mason, the Paul A. James and Charles A. Gilmore Endowed Professor at the University of Pennsylvania, School of Veterinary Medical. "Based upon this initial research, OS Therapies conducted a successful translational Phase 2b clinical trial in the rare pediatric indication of prevention of recurrence of fully resected, osteosarcoma lung metastases. Our newly published canine data and unpublished radation combination canine data expands the potential use of OST-HER2 into delay/prevention of metastasis and PFS following resected primary osteosarcoma and raises the intriguing possibility of combination radiation therapy and OST-HER2 in the treatment of unresectable osteosarcoma."
The Company is preparing to submit this data to USDA, along with new data generated on its newly patented, commercially superior manufacturing process, with the aim of gaining conditional approval for the new manufacturing process for OST-HER2 in the United States to begin sales in 2025. Thereafter, the Company intends to conduct a pivotal clinical study with the aim of gaining full approval in 2026. A link to the publication is available here: https://www.cell.com/molecular-therapy-family/molecular-therapy/abstract/S1525-0016(25)00113-3.
"It has been my dream since founding the Company that OST-HER2 could potentially change the standard of care in osteosarcoma, potentially limiting the need for amputation or surgical resection of the primary tumor," said Paul Romness, CEO of OS Therapies. "With today's data, we believe we are taking the first steps towards this given that our Comparative Oncology approach, as a result of the
Mr. Romness continued, "We are laser focused on getting an Accelerated Approval for OST-HER2 in recurrent, fully-resected, lung metastatic human osteosarcoma via Accelerated Approval by year-end 2025 and then using funds obtained from the sale of our pending Priority Review Voucher to expand the potential clinical uses of OST-HER2 throughout the human osteosarcoma treatment paradigm. In parallel, we believe the data from these two studies support the use of OST-HER2 in all phases of canine osteosarcoma treatment and we are hopeful to obtain conditional approval with our newly improved, patented manufacturing for OST-HER2 later this year so that we can launch the product at specialized cancer centers and patients can begin getting treatment very soon."
OST-HER2 is being featured in the upcoming movie Shelter Me: The Cancer Pioneers. The movie offers a look into canine comparative oncology, a field that compares treatment of cancers in dogs to those in people and covers developing treatments for rare forms of cancer. A trailer for the movie is available here. The movie will be air live nationally on PBS and will available via streaming on PBS' website in early May 2025.
About OS Therapies
OS Therapies is a clinical stage oncology company focused on the identification, development, and commercialization of treatments for osteosarcoma and other solid tumors. OST-HER2, the Company's lead asset, is an immunotherapy leveraging the immune-stimulatory effects of Listeria bacteria to initiate a strong immune response targeting the HER2 protein. OST-HER2 has received Rare Pediatric Disease Designation (RPDD) from the US Food & Drug Administration and Fast-Track and Orphan Drug designations from the US FDA and European Medicines Agency. The Company has demonstrated positive data in its Phase 2b clinical trial of OST-HER2 in recurrent, fully resected, lung metastatic osteosarcoma demonstrating statistically significant benefit in the 12-month event free survival (EFS) primary endpoint of the study. The Company anticipates submitting a BLA to the US FDA for OST-HER2 in osteosarcoma in 2025 and, if approved, would become eligible to receive a Priority Review Voucher that it could then sell. OST-HER2 has completed a Phase 1 clinical study primarily in breast cancer patients, in addition to showing preclinical efficacy data in various models of breast cancer. OST-HER2 has been conditionally approved by the U.S. Department of Agriculture for the treatment of canines with osteosarcoma.
In addition, OS Therapies is advancing its next-generation Antibody Drug Conjugate (ADC) and Drug Conjugates (DC), known as tunable ADC (tADC), which features tunable, tailored antibody-linker-payload candidates. This platform leverages the Company's proprietary silicone Si-Linker and Conditionally Active Payload (CAP) technology, enabling the delivery of multiple payloads per linker. For more information, please visit www.ostherapies.com.
Forward-Looking Statements
Statements in this press release about future expectations, plans and prospects, as well as any other statements regarding matters that are not historical facts, may constitute forward-looking statements within the meaning of the federal securities laws. These forward-looking statements and terms such as "anticipate," "expect," "intend," "may," "will," "should" or other comparable terms involve risks and uncertainties because they relate to events and depend on circumstances that will occur in the future. Those statements include statements regarding the intent, belief or current expectations of OS Therapies and members of its management, as well as the assumptions on which such statements are based. OS Therapies cautions readers that forward-looking statements are based on management's expectations and assumptions as of the date of this news release and are subject to certain risks and uncertainties that could cause actual results to differ materially, including, but not limited to the approval of OST-HER2 by the US FDA and grant of a priority review voucher and other risks and uncertainties described in "Risk Factors" and "Management's Discussion and Analysis of Financial Condition and Results of Operations" in the Company's registration statement on Form S-1 filed with the Securities and Exchange Commission (the "SEC") on November 12, 2024, as amended on November 27, 2024, and other subsequent documents we file with the SEC, including but not limited to our Quarterly Reports on Form 10-Q. Any forward-looking statements contained in this press release speak only as of the date hereof, and, except as required by the federal securities laws, OS Therapies specifically disclaims any obligation to update any forward-looking statement, whether as a result of new information, future events or otherwise.
OS Therapies Contact Information:
Jack Doll
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Irpr@ostherapies.com
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To view the source version of this press release, please visit https://www.newsfilecorp.com/release/248054
FAQ
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