Positive results from a major phase III trial provide new hope for those suffering from a prevalent type of advanced breast cancer. Roche announced that its experimental drug, giredestrant, combined with everolimus, significantly slowed cancer growth in patients with ER-positive, HER2-negative breast cancer who had not improved after standard

ER-positive breast cancer is the most common subtype, accounting for approximately 70% of all cases globally. It is a particularly severe burden in South Asia and other parts of the Global South, where late-stage diagnosis is widespread and access to innovative medicines is limited. While existing treatments are initially beneficial, cancer frequently develops resistance, particularly after using a family of medications known as CDK4/6 inhibitors, giving patients fewer options. 

Trial results

The evERA trial met its key objectives, demonstrating that the giredestrant-everolimus combination outperformed the existing standard-of-care combo in terms of progression-free survival (PFS)—the amount of time a patient may go without their cancer worsening. This advantage was evident both in the general trial population and, more interestingly, in individuals whose tumours contained ESR1 mutations, a typical cause of treatment resistance. The all-oral regimen was well tolerated, and no new safety concerns emerged. 

According to Levi Garraway, Chief Medical Officer at Roche, "These results show that the giredestrant combination provided a meaningful benefit for ER-positive breast cancer patients whose disease has progressed following treatment with a CDK inhibitor." The company intends to exhibit the entire dataset at an upcoming medical conference and will shortly begin conversations with global health authorities, particularly those in key regions in the Global South, to seek regulatory approval. 

Impact on Patients and Access

For patients, an effective all-oral regimen could be life-changing. It eliminates the need for frequent hospital trips for intravenous infusions, significantly increasing quality of life and potentially expanding access in resource-constrained countries where clinic infrastructure is overburdened. 

While the PFS results are encouraging, overall survival data are not yet complete. A longer follow-up is required to confirm the entire efficacy of the treatment. Patients and oncologists throughout the world will be watching for these developments and regulatory decisions in the coming months, hoping for a new, more comfortable choice to join the fight against this relentless disease.