Medivation has not yet decided whether it should engage with Pfizer in negotiations and is in discussions with its financial and legal advisers, Reuters reported, citing sources.
The news comes about a week after French drugmaker Sanofi made its own takeover bid for $52.50 a share in cash.
Sanofi and Pfizer did not immediately respond to CNBC's request for comment. Medivation declined to comment.
Shares of Medivation are up more than 20 percent year to date, but are down more than 5 percent in the past year.