Genentech announces lidERA Breast Cancer study meets primary endpoint

Genentech, a member of Roche (RHHBY), announced Phase III results from the lidERA Breast Cancer study evaluating investigational giredestrant as an adjuvant endocrine treatment for people with estrogen receptor-positive, human epidermal growth factor receptor 2-negative, early-stage breast cancer. The study met its primary endpoint at a pre-planned interim analysis, showing a statistically significant and clinically meaningful improvement in invasive disease-free survival with giredestrant versus standard-of-care endocrine therapy. lidERA is the first Phase III trial of a selective estrogen receptor degrader to demonstrate a significant benefit in the adjuvant setting. The majority of breast cancer cases are diagnosed at an early stage. Overall survival data were immature at the time of interim analysis, but a clear positive trend was observed. Giredestrant was well tolerated and adverse events were consistent with its known safety profile, with no unexpected safety findings observed. Data from lidERA will be presented at an upcoming medical meeting and shared with health authorities with the aim of bringing this potential treatment option to patients around the world. lidERA is the second positive Phase III readout for giredestrant following evERA Breast Cancer, which was presented at the European Society for Medical Oncology Congress 2025. The scientific rationale for lidERA was supported by prior results in the neoadjuvant setting, including the coopERA trial showing that giredestrant was superior to an aromatase inhibitor in reducing malignant cell division (Ki67 levels). This growing body of evidence supports the potential of giredestrant to meaningfully improve outcomes compared with standard-of-care endocrine therapy across ER-positive early-stage and advanced breast cancer.