News Feature | May 15, 2014

FDA Accepts Astellas And Medivation sNDA For Xtandi In Prostrate Cancer

By Cyndi Root

The Food and Drug Administration (FDA) has accepted Astellas Pharma’s and Medivation’s supplemental New Drug Application (sNDA) for Xtandi (enzalutamide). The new application is for the treatment of metastatic castration-resistant prostate cancer (mCRPC) in men who have not received chemotherapy. The FDA granted Priority Review and will respond to the application by September 18, 2014.

Tomasz M. Beer of Oregon Health & Science University, Knight Cancer Institute, the lead investigator of the Xtandi PREVAIL trials, said, “As a consequence of the efficacy as well as the safety data, I think it’s safe to say that enzalutamide provided significant clinical benefit to patients with metastatic castration-resistant prostate cancer.”

Xtandi

Xtandi is already approved for men with mCRPC who have previously received docetaxel chemotherapy. Xtandi (enzalutamide) is an androgen receptor inhibitor and an inhibitor of androgen receptor nuclear translocation and interaction with DNA. In vitro, Xtandi decreased cell proliferation and caused cell death in prostate cancer cells. In mice, it decreased tumor volume.

Xtandi Trials

The FDA accepted the sNDA based on the PREVAIL trials, Phase III studies comparing Xtandi to a placebo. Over 1,700 patients who had never received chemotherapy participated. The multi-national trial was held at sites in the U.S., Europe, Canada, Australia, Russia, Israel, and Asian countries. Patients either took 160 mg of oral enzalutamide or a placebo. Results showed a statistically significant benefit of enzalutamide over placebo with a 30 percent reduction in the risk of death and an 81 percent reduction in risk of radiographic progression or death. Twenty-eight percent of enzalutamide patients died compared to 35 percent of placebo patients who died.  

Astellas and Medivation Collaboration

Astellas and Medivation agreed to develop enzalutamide in 2009. The development program aims to investigate Xtandi for all types of prostate cancer and calls for further studies in advanced breast cancer. The two companies market Xtandi jointly in the U.S. Astellas is charged with manufacturing the drug and completing regulatory requirements. Astellas is to market Xtandi globally. The FDA’s sNDA acceptance triggers a milestone payment from Astellas to Medivation.