Johnson & Johnson's acquisition of Aragon Pharmaceuticals Inc. is reminiscent of its deal for Cougar Biotechnology Inc.: roughly $1 billion for an androgen deprivation therapy for castration-resistant prostate cancer based on promising PSA reductions but pending survival benefit. The deal gives the pharma a second-generation androgen receptor antagonist that could have the edge in efficacy over Xtandi enzalutamide from Astellas Pharma Inc. and Medivation Inc.

The acquisition also gives J&J a compound to potentially combine with its Zytiga abiraterone, which faces U.S. patent expiration in 2016.