Johnson & Johnson announced that it would engage to pay Aragon Pharmaceuticals and its experimental drugs for prostate cancer at US$1 billion. This is to strengthen J&J's role in the industry after acquiring another prostate-cancer treatment. The leading brand made the acquisition four years ago.

On Monday, J&J said that the lead product of Aragon called ARN-509 has potential to aid patients with prostate cancer that has not yet spread to other parts of the body. The drug can also help those whose cancer has already spread.

By contrast, J&J's blockbuster Zytiga treatment was approved in 2011 only for patients whose cancer has already spread. The treatment was acquired through a US$1 billion deal of Cougar Biotechnology in 2009.

Moreover, although Zytiga became a blockbuster two years after it was launched, it will face tough competition from cheaper generics by 2016 in the US. Unlike the ARN-509 that will have exclusive US marketing until 2028 stated in a research note by analyst Danielle Antalffy of Leerink Swann.