- In phase III trials, Astellas Pharma and Medivation's Xtandi (enzalutamide) improved overall survival (OS) by 29% and radiographic, progression-free survival (PFS) by 81% in men with chemotherapy-naïve metastatic castration-resistant prostate cancer (mCRPC).
- Xtandi’s original approval was for treatment of men with mCRPC after they had received chemotherapy.
- Overall, the estimated median OS was 32.4 months in Xtandi-treated men, versus 30.2 months in placebo-treated men. Note that all participants has already undergone surgery and/or received radiation therapy and hormone therapy.
Available data show that men with mCRPC who have received chemotherapy, as well as those who have not received chemotherapy, can benefit from treatment with Xtandi. The ability to delay chemotherapy and significantly extend OS, as well as PFS, suggests that Xtandi represents a value-based treatment for a broad range of men with prostate cancer.
The added indication is sure to fuel even grander sales projections by analysts and industry observers. Some analysts believe that Xtandi will cross $2.7 billion in sales by 2018, overtaking J&J's popular Zytiga -- and that was before Xtandi's label expansion.