IDEAYA Biosciences, Inc. announced that the U.S. Food and Drug Administration (FDA) has granted Fast Track designation to IDEAYA's development program investigating IDE161, a potent and selective inhibitor of poly (ADP-ribose) glycohydrolase (PARG), for the treatment of adult patients having advanced or metastatic ovarian cancer with germline oromatic BRCA 1/2 mutations who are platinum resistant and have received prior antiangiogenic and poly (ADP-ribosing) polymerase (PARP) inhibitor therapies. Fast Track is a U.S. FDA process designed to facilitate the development and expedite the review of drugs to treat serious conditions and fill an unmet medical need. Under the Fast Track designation, the IDE161 development program in BRCA1/2m ovarian cancer, as specified in the Fast Track designation, is eligible for various expedited regulatory review processes, including generally more frequent FDA interactions (e.g., meetings, written communications), potential eligibility for rolling review of a New Drug Application (NDA) and potential accelerated approval and priority review of an NDA.

IDEAYA's Phase 1 first-in-human clinical trial is evaluating the safety, tolerability, pharmacokinetic and pharmacodynamic properties and preliminary efficacy of IDE161 in patients having solid tumors with homologous combination deficiency (HRD). Early clinical data from the dose escalation cohorts showed preliminary tumor shrinkage in multiple patients having solid tumors with HRD, including a BRCA 1/2m endometrial cancer subject. These data supported expansion into priority tumor indications in parallel with continuing evaluation of the optimal move-forward dose for Phase 2 expansion.

The expansion portion of the Phase 1 trial will include patients having HRD+ associated breast cancer and ovarian cancer, as well as a basket of other selected solid tumors. The breast cancer focus is on estrogen receptor positive (ER+), human epidermal growth factor receptor 2 negative (Her2-) tumors with HRD, which represent approximately 10% to 14% of breast cancer patients. IDEAYA owns or controls all commercial rights in IDE161, subject to certain economic obligations under its exclusive, worldwide license with Cancer Research UK and University of Manchester.