FDA Approves New Therapy for Advanced Breast Cancer

The Food and Drug Administration on Sept. 25 approved a new therapy for advanced breast cancer, based on data from a phase 3 clinical trial.

Regulators said in a statement that they approved imlunestrant, also known as Inluriyo, from Eli Lilly.

The therapy, an estrogen receptor antagonist, is cleared for adults who have advanced or metastatic breast cancer with estrogen receptor-1 mutations.

Inluriyo is designed to target these overactive receptors by binding to the estrogen receptor, blocking its activity, and breaking it down to help slow the spread of the disease.

A phase 3 randomized, open-label trial with 874 patients that compared imlunestrant to a different investigational regimen, found that participants who received the therapy were more likely to survive and not have any cancer progression.

Among participants with estrogen receptor-1 mutation, median progression-free survival was 5.5 months in the therapy arm, compared to 3.8 months in the other arm, according to results posted to clinicaltrials.gov.

Adverse events among imlunestrant participants included abdominal pain and cardiac arrest. The label for the drug warns that it can cause fetal harm when taken by pregnant women, based on findings in animal studies and the drug’s mechanism of action.