Key takeaways:

• The FDA approved imlunestrant plus abemaciclib for hormone therapy-resistant ER-positive, HER2-negative advanced breast cancer.
• Approval was based on the results of the phase 3 EMBER-3 trial.

The FDA approved combination imlunestrant plus abemaciclib for adults with hormone therapy-resistant estrogen receptor-positive, HER2-negative, ESR1-mutated advanced or metastatic breast cancer.

The combination therapy (Inluriyo and Verzenio, Eli Lilly & Co.) was approved with the indication for certain patients with endocrine therapy-resistant advanced breast cancer as detected by a companion diagnostic assay (Guardant360 CDx, Eli Lilly & Co.), which also received approval, according to an FDA press release.

The FDA approved combination imlunestrant plus abemaciclib for adults with hormone therapy-resistant estrogen receptor-positive, HER2-negative, ESR1-mutated advanced or metastatic breast cancer.

“We have an urgent need for effective and safe treatment options for patients with disease progression on adjuvant or first-line therapy,” Komal Jhaveri, MD, FACP, FASCO, clinical director of the early drug development service and section head of the endocrine therapy research program at Memorial Sloan Kettering Cancer Center, said in a company press release. “Combining therapies that work on two distinct drivers of tumor growth — the estrogen receptor and CDK4/6 — is an important strategy to help address treatment resistance.”

Approval of the combination therapy was based on the results of the phase 3 EMBER-3 trial, which included 874 patients with ER-positive, HER2-negative advanced breast cancer who were randomly assigned to either imlunestrant 400 mg daily; standard endocrine therapy with fulvestrant or exemestane alone; or imlunestrant 400 mg daily plus abemaciclib.

As Healio previously reported, imlunestrant alone or in combination with abemaciclib extended PFS in this patient population, and in 2025, imlunestrant alone was approved for adults with hormone therapy-resistant ER-positive, HER2-negative advanced breast cancer.

“In EMBER-3, switching both the endocrine therapy and CDK 4/6 inhibitor, for the majority of patients, to imlunestrant plus abemaciclib at disease progression achieved a median progression-free survival of 11.1 months and a safety profile consistent with that of each medicine individually, establishing a meaningful new treatment option,” Jhaveri said in the release.