OSE Immunotherapeutics Announces Presentation of Combi-TED Phase 2 Topline Results of Tedopi® in Non-Small Cell Lung Cancer at the ESMO 2026 Meeting

OSE Immunotherapeutics Announces Presentation of Combi-TED Phase 2 Topline Results of Tedopi® in Non-Small Cell Lung Cancer at the ESMO 2026 Meeting

Nantes, France, September 23, 2026 – 7:30am CET – OSE Immunotherapeutics SA (ISIN: FR0012127173; Mnemo: OSE), a clinical-stage biotech company dedicated to developing first-in-class therapies in immuno-oncology and immuno-inflammation, today announced that topline results from the Combi-TED Phase 2 international clinical trial of Tedopi® in metastatic Non-Small Cell Lung Cancer sponsored by FoRT have been selected for an oral presentation at the 2026 Annual Meeting of the European Society for Medical Oncology (ESMO) in Madrid, Spain (October 23-27, 2026).

Federico Cappuzzo, MD, PhD, Director of Medical Oncology at the National Cancer Institute Regina Elena (Rome, Italy) and Lead Investigator of the trial, will present topline results from the Combi-TED trial evaluating Tedopi® in second-line treatment in combination with anti-PD1 or chemotherapy in patients with metastatic Non-Small Cell Lung Cancer (NSCLC).

“Results of a multicenter, phase II, open-label, randomized trial evaluating OSE2101 plus docetaxel or OSE2101 plus nivolumab as second-line therapy in metastatic non-small-cell lung cancer (NSCLC) progressing after first-line chemo-immunotherapy”

• Rapid Oral Presentation
• Session: Non-Small Cell Lung Cancer, Metastatic
• Abstract 2661RO
• Room: Barcelona Auditorium, Hall 9
• October 25, 2026, 8:30-10:00am CET

Combi-TED is an open label, randomized, three-arm Phase 2 study evaluating Tedopi® in combination with the anti-PD1 immune checkpoint inhibitor Opdivo® (nivolumab), with docetaxel or docetaxel alone (reference arm) as second-line treatment in 105 HLA-A2 positive patients with metastatic NSCLC and no evidence of EGFR mutations or ALK or ROS1 rearrangement, after first-line chemo-immunotherapy. The primary endpoint is 1-year survival rate. The trial is conducted in 23 sites in France, Italy and Spain. (NCT04884282).

ABOUT OSE IMMUNOTHERAPEUTICS

OSE Immunotherapeutics is a biotech company dedicated to developing first-in-class assets in immuno-oncology (IO) and immuno-inflammation (I&I) that address the unmet patient needs of today and tomorrow. We partner with leading academic institutions and biopharmaceutical companies in our efforts to develop and bring to the market transformative medicines for people with serious diseases. OSE Immunotherapeutics is based between Nantes and Paris and is listed on Euronext. Additional information about OSE Immunotherapeutics assets is available on the Company’s website: www.ose-immuno.com. Follow us on LinkedIn.

ABOUT FORT

FoRT (Fondazione Ricerca Traslazionale) aims to support oncology research by optimizing available treatments and striving to improve patient life expectancy. Numerous anti-cancer drugs are available in oncology; unfortunately, only a few patients benefit from these treatments, while many experience their side effects. Translational research makes it possible to identify which patients will benefit from a treatment and which will not. Translational research also helps determine the prognostic value of various biological factors, allowing physicians to better predict the progression of the disease. FoRT’s activities include promoting clinical and preclinical studies, supporting scientific initiatives, and disseminating and publishing the resulting scientific data. Furthermore, FoRT seeks to provide concrete assistance to patients in navigating the management of their disease and accessing the best available therapeutic options. More information on www.fondazionefort.org.

Contacts

OSE Immunotherapeutics: investors@ose-immuno.com

FP2COM (Media Relations): Florence Portejoie: fportejoie@fp2com.fr I +33 6 07 768 283

Astr Partners (Investor Relations): Guillaume Cabon: guillaume.cabon@astrpartners.com I +33 6 95 06 92 06

Forward-looking statements

This press release contains express or implied information and statements that might be deemed forward-looking information and statements in respect of OSE Immunotherapeutics. They do not constitute historical facts. These information and statements include financial projections that are based upon certain assumptions and assessments made by OSE Immunotherapeutics’ management considering its experience and its perception of historical trends, current economic and industry conditions, expected future developments and other factors they believe to be appropriate.

These forward-looking statements include statements typically using conditional and containing verbs such as “expect”, “anticipate”, “believe”, “target”, “plan”, or “estimate”, their declensions and conjugations and words of similar import. Although the OSE Immunotherapeutics management believes that the forward-looking statements and information are reasonable, the OSE Immunotherapeutics’ shareholders and other investors are cautioned that the completion of such expectations is by nature subject to various risks, known or not, and uncertainties which are difficult to predict and generally beyond the control of OSE Immunotherapeutics. These risks could cause actual results and developments to differ materially from those expressed in or implied or projected by the forward-looking statements. These risks include those discussed or identified in the public filings made by OSE Immunotherapeutics with the AMF. Such forward-looking statements are not guarantees of future performance. This press release includes only summary information and should be read with the OSE Immunotherapeutics Universal Registration Document filed with the AMF on June 4, 2026, including the annual financial report for the fiscal year 2025, available on the OSE Immunotherapeutics’ website. Other than as required by applicable law, OSE Immunotherapeutics issues this press release at the date hereof and does not undertake any obligation to update or revise the forward-looking information or statements.