Roche’s phase III evERA data showed giredestrant significantly improved progression-free survival in people with ER-positive advanced breast cancer

Core Insights - Roche announced positive results from the phase III evERA Breast Cancer study, showing that giredestrant combined with everolimus significantly reduced the risk of disease progression or death by 44% in the intention-to-treat (ITT) population and 62% in the ESR1-mutated population compared to standard-of-care endocrine therapy plus everolimus [1][6]. Study Details - The evERA study evaluates giredestrant in combination with everolimus for patients with ER-positive, HER2-negative, locally advanced or metastatic breast cancer who have previously been treated with CDK 4/6 inhibitors and endocrine therapy [1][8]. - This study is the first positive head-to-head phase III trial investigating a selective estrogen receptor degrader-containing regimen versus a standard-of-care combination [1]. Efficacy Results - In the ITT population, the median progression-free survival (PFS) was 8.77 months for the giredestrant group compared to 5.49 months for the comparator group (HR=0.56, p-value <0.0001) [3]. - In the ESR1-mutated population, the median PFS was 9.99 months for the giredestrant group versus 5.45 months for the comparator group (HR=0.38, p-value <0.0001) [3]. - Overall survival (OS) data were immature, but a positive trend was observed in both populations [3][6]. Safety Profile - The giredestrant-based combination was well tolerated, with manageable adverse events consistent with the known safety profiles of the individual medicines, and no new safety signals were observed [4][6]. Market Implications - If approved, giredestrant plus everolimus could become the first and only oral selective estrogen receptor degrader combination in the post-CDK inhibitor setting, addressing a significant unmet need for patients resistant to current therapies [2][6]. - Approximately 70% of breast cancer cases are ER-positive, and resistance to endocrine therapies is common, highlighting the potential market for giredestrant [5][12]. Clinical Development - Roche has an extensive clinical development program for giredestrant, which includes multiple phase III trials across various treatment settings to maximize its benefit for patients with ER-positive breast cancer [7][11].