Eli Lilly’s breast cancer drug Verzenio (abemaciclib) has achieved a significant milestone, with new study results showing it helps people with a common form of early-stage breast cancer live longer. These findings, announced August 27, 2025 and reported by BioPharma Dive, come from the long-running monarchE trial, which began in 2017 and enrolled more than 5,600 adults with high-risk, hormone receptor-positive, HER2-negative (HR+, HER2-) breast cancer.
Verzenio, a CDK4/6 inhibitor, was tested in combination with standard hormone therapy and compared to hormone therapy alone. According to Lilly, the addition of Verzenio resulted in a “statistically significant and clinically meaningful” improvement in overall survival—a secondary endpoint of the trial. While specific survival data have not yet been released, the company will present full results at an upcoming medical meeting and submit the findings to regulators and for publication.
The monarchE study had previously demonstrated that Verzenio, when used alongside hormone therapy, reduced the risk of invasive breast cancer recurrence compared to hormone therapy alone. Those results were pivotal in securing Verzenio’s 2021 approval for use in early-stage, high-risk HR+, HER2- breast cancer, making it the first drug in its class to be approved for this setting.
This latest survival benefit strengthens Verzenio’s role as a standard-of-care treatment for patients with node-positive, high-risk disease. “These data validate Verzenio as the standard-of-care… and increase the urgency to ensure all eligible patients are treated,” said Jacob van Naarden, head of Lilly Oncology.
Safety results from the extended follow-up were in line with what was previously observed, suggesting no new or unexpected side effects. Verzenio has been on the market since 2017, originally approved for advanced or metastatic breast cancer, and has since become one of Lilly’s top-selling drugs, with $5.3 billion in sales last year.
Rival CDK4/6 inhibitors from Pfizer and Novartis have also shown benefits in early breast cancer, but the monarchE trial is distinct in its focus on patients whose cancer had already spread to the lymph nodes—a group at particularly high risk of recurrence and death. Novartis’ Kisqali has also demonstrated strong results in a broader patient population, but monarchE’s findings reinforce the unique benefit of Verzenio in those with node-positive disease.
