FDA expands label for Pfizer, Astellas' Xtandi to include non-metastatic castration-resistant prostate cancer

Pfizer and Astellas announced Friday that the FDA has approved their application to expand the indication for Xtandi (enzalutamide) to include the treatment of men with non-metastatic castration-resistant prostate cancer (CRPC). The decision makes the once-daily androgen receptor inhibitor the first oral treatment approved in the US for both non-metastatic and metastatic CRPC, the companies noted. 

Andy Schmeltz, global president at Pfizer's oncology division, said "this approval delivers on the potential for Xtandi to help men at an earlier stage of the disease." He added "we are continuing to evaluate the medicine in an extensive development programme across additional prostate cancer populations." 

FirstWord reports in this therapy area - KOL Insight Prostate Cancer: Find out how KOLs expect the market to evolve, which pipeline treatments are most promising, and which clinical trials will shape treatment decisions. Learn more. 

The approval was based on data from the 1401-patient Phase III PROSPER trial, recently published in the NEJM, which demonstrated that Xtandi plus androgen deprivation therapy (ADT) significantly cut the risk of metastasis or death compared to ADT alone in men with non-metastatic CRPC. Specifically, the median duration of metastasis-free survival (MFS), the study's primary endpoint, was 36.6 months for Xtandi-treated patients, compared with 14.7 months for those on ADT alone. 

Pfizer and Astellas noted that the primary outcome was also "supported by a statistically significant delay in the time to first use of new antineoplastic therapy for patients who received Xtandi plus ADT compared to those who received ADT alone," at 39.6 months versus 17.7 months, respectively. Overall survival data were not mature at the time of final MFS analysis, the companies said. 

Xtandi was first cleared in the US in 2012 for patients with metastatic CRPC previously treated with docetaxel, and was later expanded to include treatment of metastatic CRPC in chemotherapy-naïve men. 

To read more Top Story articles, click here.