The U.S. Food and Drug Administration has accepted a filing for expanded approval and granted priority review to an application for Pfizer Inc. and Astellas Pharma Inc.'s Xtandi, or enzalutamide.
If the application is approved, Xtandi's indication will expand to treat castration-resistant prostate cancer in patients who have not seen the disease spread to other parts of the body, based on data from a phase 3 study.
The FDA grants priority review designation to applications for drugs that, if approved, may offer significant improvements in the safety and effectiveness of the treatment of serious conditions when compared to standard applications.
Castration-resistant prostate cancer refers to the subset of men whose prostate cancer progresses despite castration levels of testosterone.
In the study, Xtandi and a standard hormone therapy, known as androgen deprivation therapy, reduced the risk of disease progression or death by 71% in men with the early form of prostate cancer.
The FDA approved Xtandi in 2012 to treat castration-resistant prostate cancer where the disease has spread to other parts of the patient's body and the patients had previously received chemotherapy medication docetaxel. In 2014, Xtandi was approved to treat castration-resistant prostate cancer in patients who have seen the cancer spread to other parts of the body.
Under a 2009 agreement, Pfizer and Astellas jointly commercialize Xtandi in the U.S. and Astellas has responsibility for manufacturing and all additional regulatory filings globally, as well as commercializing the drug outside the U.S.