IDEAYA Targets Major UC Subset with New Phase 1/2 Combo Study of IDE397 and Gilead’s Trodelvy

IDEAYA Biosciences (Nasdaq: IDYA), a precision oncology company focused on targeted therapeutics, has announced the initiation of a Phase 1/2 expansion in its ongoing clinical trial evaluating IDE397, a first-in-class investigational MAT2A inhibitor, in combination with Gilead’s Trodelvy® (sacituzumab govitecan-hziy) for patients with MTAP-deletion urothelial cancer (UC).

This next phase of the study follows encouraging early safety and efficacy data observed in the ongoing trial. IDE397 is a potent and highly selective small molecule that targets methionine adenosyltransferase 2A (MAT2A), specifically in tumors with MTAP-deletion—a genetic alteration found in approximately 26% of UC cases.

“We’re excited to move this potential first-in-class combination forward,” said Darrin Beaupre, M.D., Ph.D., Chief Medical Officer at IDEAYA Biosciences. “Given there are currently no approved therapies specifically for MTAP-deletion urothelial cancer, this represents a promising avenue to address a major unmet need.”

Trodelvy, already approved for various breast cancer indications, is being explored here in an investigational context. The use of this antibody-drug conjugate in MTAP-deletion UC is not yet approved, and its safety and efficacy for this indication remain under investigation.

Looking ahead, IDEAYA plans to:

• Share a clinical program update on the IDE397–Trodelvy combination in 2025.

• Continue monotherapy expansion studies in MTAP-deletion non-small cell lung cancer (NSCLC) and UC.

• Launch a new trial in late 2025, combining IDE397 with IDE892, its internally developed MTA-cooperative PRMT5 inhibitor.

Under the terms of their collaboration, IDEAYA retains full commercial rights to IDE397, and Gilead retains rights to Trodelvy, whether as standalone treatments or in combination. IDEAYA is leading the clinical trial and Gilead is supplying Trodelvy.