IDEAYA Biosciences, Inc. (NASDAQ: IDYA), a California-based precision medicine oncology company, announced on Wednesday that it has received fast track designation from the US Food and Drug Administration (FDA) for its development program investigating IDE161, a potent and selective inhibitor of poly (ADP-ribose) glycohydrolase (PARG).

IDE161 is intended for the treatment of adult patients having advanced or metastatic hormone receptor positive (HR+), Her2- breast cancer with germline or somatic BRCA 1/2 mutations who have progressed subsequent to treatment with at least one line of a hormonal therapy, a CDK4/6 inhibitor therapy and a poly (ADP-ribose) polymerase (PARP) inhibitor therapy.

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 tumours with homologous recombination deficiency (HRD). Early clinical data from the dose escalation cohorts showed preliminary tumour shrinkage in multiple patients having solid tumours with HRD, including in subjects with BRCA 1/2m endometrial cancer and colon cancer. These data supported expansion into priority tumour indications in parallel with continuing evaluation of the optimal move-forward dose for Phase 2 expansion.

IDEAYA is targeting program updates for IDE161 in the fourth quarter of 2023. 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.