You should be safe as the news may very well not hit until right after option expiration. Even if it does hit early though, $45 could be it on the upside, and you'll get all the capital appreciation as well. If I had to forecast, options will expire worthless and then the announcement will hit & you'll get the best of both worlds.
Personally, I think that was a risky move. If the FDA encourages SRPT to file for AA, the stock will almost certainly hit $45. Whether or not that comes before April opex remains to be seen. Close call.