Medivation (MDVN) sees an afternoon spike, now up $1.60 to $12, on 4X average daily volume. 6860 calls and 650 puts traded. Sep 10 calls are the most actives, with 2700 traded and 96 percent at the ask. Sep 12.5, Oct 11 and Oct 12 calls are seeing interest as well. Top trade is 500 of the Sep 10s at the 80 cent ask price about 25 minutes ago. It’s now bid at $1.84. Not clear what is driving the action.