IDEAYA Biosciences, Inc. announced it has entered into a clinical study collaboration and supply agreement with Gilead Sciences, Inc. (Gilead) to evaluate the efficacy and safety of IDE397, its investigational, potential first-in-class, small molecule MAT2A inhibitor, in combination with Gilead's sacituzumab-govitecan-hziy, a Trop-2 directed antibody-drug conjugate (ADC), in a Phase 1 clinical trial. IDEAYA is a potent and selective small molecule inhibitor targeting methionine adenosyltransferase 2a (MAT2A), in patients having solid tumors with methylthioadenosine phosphorylase (MTAP) deletion. The MTAP deletion patient population is estimated to represent approximately 15% of solid tumors, including approximately 19% of squamous NSCLC and 26% of bladder cancer.

Sacituzumab govitecan, commercialized under the brand name Trodelvy, is a Trop-2 directed antibody -drug conjugate currently approved in the U.S. for the treatment of HR+/HER2-metastatic breast cancer, metastatic triple-negative breast cancer and metastatic urothelial cancer. IDEAYA is evaluating IDE397 in an ongoing Phase 1/2 clinical trial. The company has initiated and is actively enrolling patients into monotherapy expansion in squamous NSCLC and bladder cancer and collaborating with Amgen in a Phase 1 combination study with AMG 193, Amgen's MTA-Cooperative PRMT5 inhibitor.

Under the clinical study collaboration and supply agreement, Gilead will provide drug supply to IDEAYA, which will be the sponsor of the Phase 1 clinical combination trial. IDEAYA and Gilead each retain all commercial rights to their respective compounds, including as monotherapy or as combination therapies.