Mar. 16 at 11:14 AM
$RLAY Relay Therapeutics announces data from Phase 1/2 ReDiscover trial
Relay Therapeutics announced data from the Phase 1/2 ReDiscover trial of zovegalisib + fulvestrant at the recommended Phase 3 dose of 400mg twice daily taken with food in patients with PI3Kalpha-mutated, HR+/HER2- metastatic breast cancer. The data are being presented at the European Society for Medical Oncology Targeted Anticancer Therapies Congress 2026 in Paris, France. Phase 1/2 ReDiscover Trial - Zovegalisib 400mg Fed Cohort Data Consistent with 600mg Fasted Data: Zovegalisib is currently being evaluated in ReDiscover, an ongoing first-in-human study designed to evaluate the safety, tolerability, pharmacokinetics, pharmacodynamics and preliminary antitumor activity of zovegalisib in combination with fulvestrant and in combination with fulvestrant and CDK inhibitors in patients with PI3Kalpha-mutated, HR+/HER2- metastatic breast cancer.
As of the January 13, 2026 data cut-off date, 60 patients had received the 400mg BID fed regimen. The efficacy population consisted of 57 patients who did not have a PTEN or AKT co-mutation, consistent with the planned pivotal population. All patients had previously received a CDK4/6 inhibitor and at least one prior endocrine therapy in the advanced setting. Pharmacokinetic analyses demonstrate that the 400mg BID fed regimen achieves exposures comparable to the previously evaluated 600mg BID fasted dose, with mean concentrations approaching IC90 in majority of patients and nearly all patients maintaining exposure above the IC80 throughout the dosing interval. As of the January 13, 2026 data cut-off date, among the 57 efficacy-evaluable patients at the 400mg BID fed dose, which is the recommended Phase 3 dose: Median follow-up was 12.0 months; Median progression-free survival was 11.1 months; Median PFS was 11.2 months in patients with kinase mutations and 11.0 months in patients with non-kinase mutations;
Among 35 patients with measurable disease, confirmed objective response rate was 43% and in second line only patients the ORR was 52%; Zovegalisib + fulvestrant at the 400mg BID fed dose was generally well tolerated in the 60 treated patients as of the January 13, 2026 data cut-off. The overall tolerability profile consisted primarily of low-grade, manageable and reversible treatment-related adverse events; Safety profile consistent with previously disclosed 600mg BID fasted data; Majority of hyperglycemia events were Grade 1; no Grade 4-5 hyperglycemia observed; In the limited cases of Grade 2/3 hyperglycemia, the vast majority occurred in patients that were pre-diabetic at baseline; Only four patients discontinued due to TRAEs.
