Genentech announces persevERA Breast Cancer study did not meet primary endpoint

Genentech, a member of Roche (RHHBY), announced results from the Phase III persevERA Breast Cancer study evaluating investigational giredestrant in combination with palbociclib for people with estrogen receptor-positive, human epidermal growth factor receptor 2-negative, locally advanced or metastatic breast cancer. The study did not meet its primary objective of a statistically significant improvement in progression-free survival in the intent-to-treat population versus letrozole plus palbociclib, but a numerical improvement was observed. The adverse events for the giredestrant combination were manageable and consistent with the known safety profiles of each individual treatment. evERA was the first positive Phase III readout for giredestrant, followed by lidERA in the early-stage setting. The scientific rationale for lidERA was supported by prior results in the neoadjuvant setting, including the Phase II coopERA trial showing that giredestrant was superior to an aromatase inhibitor in reducing malignant cell division. This growing body of evidence underscores the potential of giredestrant to become a new standard-of-care endocrine therapy across ER-positive early-stage and advanced breast cancer. persevERA is the first of two distinct Phase III studies in the first-line setting; the pionERA study of giredestrant in combination with physician’s choice of cyclin-dependent kinase 4/6 inhibitor in endocrine-resistant ER-positive, HER2-negative breast cancer is expected to readout in 2027. The FDA recently accepted the new drug application based on the evERA data. In the coming weeks, Genentech will submit the giredestrant Phase III lidERA data in early-stage breast cancer to the FDA. The full results from persevERA will be presented at an upcoming medical meeting.