Relay Therapeutics Reports Q4/FY 2025 Results, Outlines 2026 Milestones for Zovegalisib

Relay Therapeutics reported fourth quarter and full year 2025 financial results and outlined anticipated 2026 milestones, including initial data from its lead asset zovegalisib in PIK3CA-driven vascular anomalies and breast cancer triplet data. The company ended Q4 2025 with approximately $555 million in cash, cash equivalents and investments.

Zovegalisib, the first pan-mutant selective PI3Kα inhibitor to enter clinical development, recently received Breakthrough Therapy designation from the FDA. Initial Phase 1 data of zovegalisib in PIK3CA-driven vascular anomalies are expected to be announced in the first half of 2026. The pediatric cohort in the Phase 1 ReInspire trial recently opened ahead of schedule due to faster than expected enrollment, and the company anticipates reporting on approximately 20 patients at the time of disclosure. Breast cancer triplet data and frontline Phase 3 plans are expected in 2026.

Initial Phase 1/2 data of zovegalisib plus fulvestrant at the 400 mg twice-daily fed dose (the Phase 3 dose) in CDK4/6-experienced patients will be presented at the ESMO TAT Congress on March 16, 2026, in Paris. The accepted abstract focuses on 57 patients with HR+/HER2-, PI3Kα-mutated metastatic breast cancer previously treated with a CDK4/6 inhibitor. The company also presented data from the Phase 1/2 ReDiscover trial at ASCO 2025 and the 2025 San Antonio Breast Cancer Symposium. In the SABCS summary with an October 15, 2025 data cut-off, median progression-free survival was 10.3 months for all patients (n=52); among 31 patients with measurable disease, the objective response rate was 39%. For second-line patients, median PFS was 11.4 months and ORR was 47%, with a median follow-up of 20.2 months. For patients who received a prior SERD, median PFS was 11.4 months and ORR was 44% (7/16), and for patients with a detectable ESR1 mutation at baseline, median PFS was 8.8 months and ORR was 60% (6/10). The tolerability profile remained consistent with mutant-selective PI3Kα inhibition, with treatment-related adverse events that were mostly low-grade, manageable and reversible.

Triplet cohorts of zovegalisib in combination with atirmociclib, ribociclib, or palbociclib are ongoing to inform the preferred frontline Phase 3 regimen. The company continues execution of the Phase 3 ReDiscover-2 trial of zovegalisib plus fulvestrant in PI3Kα-mutated, CDK4/6 pre-treated, HR+/HER2- advanced breast cancer.

Relay Therapeutics also announced that it will report first quarter 2026 financial results after the U.S. financial markets close on Tuesday, May 5, 2026, and second quarter 2026 results after market close on Thursday, August 6, 2026.