Zytiga, first approved in 2011, is on sale in more than 60 countries, including the U.S.
Cancer of the prostate, the gland surrounding the urethra that produces part of the seminal fluid, can progress so slowly that treatment isn't needed, or it can grow and spread to other body parts very quickly, depending on the individual patient and characteristics of his tumor.
Each year, prostate cancer kills roughly 90,000 men in Europe and about 28,000 in the U.S.
Shares of Johnson & Johnson rose 20 cents to $72.39 in afternoon trading Friday. They are near the high end of their 52-week range of $61.71 to $72.74.