OSE Immunotherapeutics Receives Second Positive IDMC Recommendation for Phase 3 ARTEMIA Trial Evaluating Tedopi® in Non-Small Cell Lung Cancer

26 Feb 2026 18:00 CET

NANTES, France, February 26, 2026 – 6pm CET - OSE Immunotherapeutics SA (ISIN: FR0012127173; Mnemo: OSE), today announced that the Independent Data Monitoring Committee (IDMC) has issued a second positive recommendation for the ongoing pivotal Phase 3 ARTEMIA trial evaluating Tedopi® in advanced non-small cell lung cancer (NSCLC). The IDMC advised that the study should continue as planned, with no protocol changes.

In line with the predefined study oversight plan, the IDMC, composed of independent clinical and statistical experts, conducted a comprehensive assessment of patient safety, trial conduct and key efficacy indicators. Based on this review, the IDMC recommended that the study continue without modifications, confirming the robustness of the trial’s conduct to date.

Dr. Silvia Comis, Chief Clinical and Medical Research Officer at OSE Immunotherapeutics, commented: “We welcome this new positive assessment from the IDMC. A total of 163 patients had been randomized at the time of the meeting, with 152 included in the analysis reviewed by the IDMC. These figures are fully consistent with our recruitment objectives.”

Initiated in 2024, ARTEMIA compares Tedopi® monotherapy with standard docetaxel in HLA-A2–positive patients with metastatic NSCLC who have developed secondary resistance to immune checkpoint inhibitors. The trial is enrolling across sites in Europe, the UK, the US and Canada and is designed to generate confirmatory data to support potential regulatory filings.

The next IDMC review is scheduled for October 2026. Study enrollment is expected to conclude by year-end 2026. Tedopi® NSCLC Pivotal Phase 3 interim futility analysis is expected in Q3 2026, with overall survival primary endpoint results anticipated in Q1 2028.

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.

Contacts

OSE Immunotherapeutics: investors@ose-immuno.com

FP2Com: Florence Portejoie: fportejoie@fp2com.fr I +33 6 07 768 283

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 April 30, 2025, including the annual financial report for the fiscal year 2024, 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.

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