Novel Therapeutic Approaches to Target PI3K Mutations in HR+/HER2– Breast Cancer

Komal Jhaveri, MD, FACP, discusses findings from the dose-escalation portion of the first-in-human phase 1 ReDiscover trial (NCT05216432) of the PI3Kα inhibitor RLY-2608 in patients with PIK3CA-mutant advanced breast cancer.

Julia E. McGuinness, MD, discusses combating gastrointestinal toxicities in PI3K-mutated breast cancer.

Erika P. Hamilton, MD, director, Breast and Gynecologic Cancer Research, Sarah Cannon Research Institute, discusses the potential of the PI3K inhibitor RLY-2608 in PI3K-mutated breast cancer.

RLY-2608 led to sustained target inhibition with minimal effect on glucose homeostasis, acceptable safety, and antitumor activity in patients with PIK3CA-mutant solid tumors, according to interim data from the dose-escalation portion of the first-in-human phase 1 ReDiscover trial.

Julia E. McGuinness, MD, discusses the rationale for combining this novel PI3K inhibitor with fulvestrant and emphasized the importance of developing increasingly mutant-specific PI3K inhibitors in hormone receptor–positive breast cancer.