Onxeo Enters Clinical Research Agreement with Gustave Roussy to Conduct Clinical Trial of AsiDNA for Treatment of Relapsed Ovarian Cancer

Regulatory News:

Onxeo S.A. (Euronext Paris, NASDAQ Copenhagen: ONXEO), (“Onxeo” or “the Company”), a clinical-stage biotechnology company specializing in the development of innovative drugs targeting tumor DNA Damage Response (DDR), in particular against rare or resistant cancers, today announces that the Company has entered into a Clinical Research Agreement with Gustave Roussy (“Gustave Roussy”), the leading European cancer center, to conduct the REVOCAN¹ phase 1b/2 study designed to evaluate the effect of AsiDNA, Onxeo’s first-in-class DDR inhibitor, on the acquired resistance to PARP inhibitor (PARPi) niraparib in its approved indication for 2^nd line maintenance treatment of relapsed ovarian cancer.

“This is a major clinical milestone for Onxeo as we embark in this key study aiming to demonstrate that the addition of AsiDNA abrogates the tumor resistance to PARP inhibitors, which would in turn improve patients’ progression-free survival,” said Olivier de Beaumont, Chief Medical Officer of Onxeo. “We are excited and honored to be collaborating with Gustave Roussy, one of the world’s leading academic institutions, in a study that would open the way to AsiDNA becoming a must-have treatment to prevent or abrogate resistance to targeted therapies in cancer treatment.”

"Gustave Roussy and Onxeo will conduct an original proof-of-concept study of the reversion of the mechanism of resistance to a major therapeutic class. If positive, this first study, labeled by the GINECO² group, may pave the way for further combination studies with this therapeutic class, in ovarian cancer but also in other pathologies, and offer patients who benefit from these treatments an additional opportunity to control their disease," said Patricia Pautier, MD, oncologist, head of the Gynecological Cancers Committee at Gustave Roussy and principal investigator of the study.

While niraparib significantly delayed cancer progression in both patients with and without a BRCA mutation³, treatment efficacy diminishes overtime as tumors establish new repair pathways and resist to treatment. In preclinical studies, AsiDNA has consistently demonstrated its capacity to prevent or abrogate the acquired resistance of the tumors to PARP inhibitors, regardless of tumor mutations.

Gustave Roussy and Onxeo have collaborated on REVOCAN multi-center trial design that Gustave Roussy will submit, as study sponsor, to the French health authority (ANSM) and Ethics Committee in the coming weeks, with the aim to start enrolling patients in the first semester of 2020 and obtain preliminary results before year-end.