Kainova Therapeutics Announces Positive Phase I Results for DT-9081, an Oral EP4 Receptor Antagonist, in Advanced Solid Tumors

• Phase I results demonstrate favorable safety, sustained target engagement, and early signs of anti-tumor activity
• Reinforce EP4 receptor antagonism as a validated, high-value strategy to overcome immunotherapy resistance 

Montreal, Canada – Strasbourg, France – Boston, United States, March 10, 2026: Kainova Therapeutics (“the Company”), a key player for breakthrough treatments in immuno-oncology and inflammation, today announced positive topline results from its Phase I EPRAD study evaluating DT-9081, a proprietary, oral small molecule EP4 receptor (EP4R) antagonist in patients with advanced, recurrent, and metastatic solid tumors.

The study, conducted across four sites in France and Belgium, met all primary objectives. Results demonstrated a favorable safety profile, robust pharmacokinetic (PK) and pharmacodynamic (PD) characteristics with dose-proportional exposure, and sustained EP4 receptor engagement across all tested doses, with early signs of anti-tumor activity.

No dose-limiting toxicities were reported at any dose level, confirming DT-9081’s clinical tolerability and validating its mechanism of action. The Phase I findings further support DT-9081’s potential to improve responses to immune checkpoint inhibitors (ICIs). Full Phase I study details are available on clinicaltrials.gov under identifier NCT05582850.

Professor Jean-Pascal Machiels, Principal Investigator of the EPRAD study, commented: “The results of the study not only validate EP4 receptor antagonism as a powerful mechanism to counteract PGE2-driven immune suppression, but also demonstrate the clinical potential of DT-9081 across a range of tumor types. Since chemotherapy and other standard treatments often trigger PGE2 production by cancer cells, restoring competence through selective EP4 inhibition offers a rational and versatile strategy to overcome resistance. It was my honor to contribute to the advancement of DT-9081 through the clinic.”

Dr Jean-Marie Cuillerot, Chief Medical Officer of Kainova Therapeutics, said: “The Phase I EPRAD study generated a clear and coherent dataset that precisely characterizes DT-9081’s clinical profile. Across all dose levels, we observed consistent safety findings together with robust PK/PD readouts. The high-quality clinical and translational data obtained in this study are essential for understanding how EP4 antagonism behaves in patients with advanced solid tumors in a clinical setting.”

Sean A. MacDonald, Chief Executive Officer of Kainova Therapeutics, added: “The successful completion of this Phase I study represents an important step for Kainova Therapeutics, highlighting the strength of our innovative approach to targeting the EP4 receptor to overcome tumor-induced immunosuppression. The favorable safety and early efficacy signals observed with DT-9081 provide meaningful insight into EP4 biology and its role in immuno-oncology. These findings reflect the depth of expertise within our team and reinforce the relevance of GPCR-modulating strategies in addressing complex immune pathways.”