Relay Therapeutics’ Zovegalisib Granted FDA Breakthrough Therapy Status for PIK3CA-Mutant Breast Cancer
Relay Therapeutics, Inc. has announced that the U.S. Food and Drug Administration (FDA) has granted Breakthrough Therapy Designation (BTD) to zovegalisib (RLY-2608) in combination with fulvestrant for adults with PIK3CA-mutant, hormone receptor-positive, HER2-negative (HR+/HER2-) locally advanced or metastatic breast cancer.
The designation applies to patients whose disease has recurred or progressed after treatment with a CDK4/6 inhibitor.
Approximately 40% of patients with HR+/HER2- advanced breast cancer carry PIK3CA mutations, and options are limited once disease progresses on standard therapies.
Zovegalisib is a selective, allosteric PI3Kα inhibitor designed to target mutant forms while minimising effects on wild-type PI3Kα and other isoforms, addressing a key limitation of previous therapies.
The BTD is supported by early clinical data from the Phase 1/2 ReDiscover trial, which evaluated safety, tolerability, pharmacokinetics, and preliminary anti-tumour activity of zovegalisib in combination with fulvestrant.
Data from these studies suggest promising efficacy and a manageable safety profile, supporting further development.
The FDA’s Breakthrough Therapy designation provides eligibility for expedited review and enhanced guidance, reflecting the potential of zovegalisib to improve outcomes for patients with this common and challenging form of advanced breast cancer. Phase 3 studies are ongoing to confirm these findings.
