Enobosarm inhibits breast cancer development: Study

[Courtesy of Park Systems]

Enobosarm, a new experimental drug, stimulates the androgen receptor on cancer cells, which functions as a tumor suppressor, according to a clinical trial result.

Enobosarm is a selective androgen receptor targeting agonist developed by Veru Inc. The U.S. Food and Drug Administration has granted a fast-track designation to the experimental drug for the treatment of patients with androgen receptor (AR)–positive, estrogen receptor (ER)–positive, HER2-negative metastatic breast cancer.

The Phase 2, multi-site international study led by Dr Beth Overmoyer of the Dana-Farber Cancer Institute of Boston, the United States, evaluated the efficacy and safety of enobosarm in 136 postmenopausal women with locally advanced or metastatic ER-positive, HER2-negative breast cancer.

Enobosarm was found to have anti-tumor effects and was well tolerated with no significant impact on quality of life, according to reports of HealthDay News on Thursday.

This is the first approach that involves a non-estrogen receptor hormonal therapy to show clinical improvements in ER-positive breast cancer.

In the clinical study, patients were randomized to 9 mg or 18 mg of oral enobosarm daily over an average of seven and a half months. The primary endpoint was the clinical benefit rate at six months.

The drug was found to show significant clinical benefits, including anti-cancer activity.

The clinical benefit rate was 32 percent in the 9-mg group compared with 29 percent in the 18-mg group.

Average progression-free survival (PFS) was 5.6 months in the 9mg-dose group and 4.2 months in the higher-dose group.

Eight percent of the 9-mg group had drug-related adverse events, such as liver damage and fatigue, with 16 percent in the 18-mg group.