CAMBRIDGE, UK and MONTREAL, CANADA, 9 November 2026 – Epitopea, a clinical-stage, biotech company developing off-the-shelf, durable RNA-based cancer vaccines, announced today that the first patient has been successfully dosed in OVACT, its first-in-human Phase 1/1b clinical trial evaluating its lead program, CryptiVax™-1001, targeting advanced high-grade serous ovarian cancer (HGSOC).

OVACT is a Phase 1/1b dose escalation trial designed to evaluate the safety, tolerability, immunogenicity, and early clinical activity of CryptiVax™-1001 in HRP+/BRCA-wildtype advanced HGSOC patients. Up to 30 women will be enrolled into the trial across up to 10 leading clinical centres in the UK.

HGSOC remains one of the most difficult-to-treat solid tumors, with around 80% of patients presenting with advanced or metastatic disease. While most women respond to first-line platinum chemotherapy, nearly all ultimately relapse and progress to platinum-resistant disease. Existing maintenance options are only effective in half of the ovarian cancer population and leave a major therapeutic gap among HRP+/BRCA-wildtype patients.

Dr. Klaus Edvardsen, MD, PhD, Chief Medical Officer of Epitopea, commented, “HGSOC is the most common and aggressive subtype of ovarian cancer. Treating the first patient with CryptiVax™-1001 in our OVACT Phase 1/1b trial for HGSOC is a major milestone for Epitopea. Epitopea’s approach targets a novel repertoire of tumor-specific antigens that have been selected to provide broader patient benefit. We are motivated by the potential to provide meaningful durable treatment options for this underserved patient population.”

Professor Susana Banerjee (MBBS MA PhD FRCP), the Chief Investigator of Epitopea’s OVACT trial, Consultant Medical Oncologist and Research Lead for the Gynaecology Unit at The Royal Marsden NHS Foundation Trust and Professor in Women’s Cancers at The Institute of Cancer Research, London, said, “It is exciting to offer patients the option of the OVACT trial and I am delighted that we are underway with the first patient treated. The CryptiVax™-1001 vaccine has the potential to meaningfully extend remission for women where currently available maintenance therapies deliver limited durable benefit.”