Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of Medivation (NASDAQ:MDVN), a biopharmaceutical company primarily focused on developing cancer therapies, surged by as much as 11% after reporting its first-quarter results after the closing bell last night.

So what: For the quarter, Medivation and marketing partner Astellas Pharma (NASDAQOTH:ALPMY) reported sales growth for prostate cancer drug Xtandi of 65% in the U.S. to $124.5 million and astronomical ex-U.S. growth to $47.8 million from just $0.3 million in the prior year period. Collaboration revenue as it relates to Medivation soared 89% to $87.2 million. Net loss, on the heels of higher Xtandi sales, shrank 50% to $13.7 million or $0.18 per share, from $27.2 million, or $0.36 per share in the year-ago quarter. By comparison, both figures actually missed the Street's forecast of a $0.09 per share loss and $98.4 million in revenue. For the remainder of the year Medivation projected U.S. Xtandi sales would reach $540 million-$575 million.

Now what: Normally a company wouldn't be launching higher after missing Wall Street's top- and bottom-line estimates, but the consensus from analysts seems to be that Medivation was being pretty conservative with its growth guidance for Xtandi for the remainder of the year. In addition, it's not as is Medivation is standing still -- collaborative revenue did jump 89% during the quarter and it halved its net loss. Medivation looks well on its way to becoming profitable and is successfully taking on, and taking down, some fierce competition in the late-stage prostate cancer space. Assuming Xtandi receives the thumbs up from the Food and Drug Administration in a prechemo setting we could really see sales of the therapy take off. In other words, you may want to add Medivation to your watchlist after its recent dip.

Sean Williams has no material interest in any companies mentioned in this article. You can follow him on CAPS under the screen name TMFUltraLong, track every pick he makes under the screen name TrackUltraLong, and check him out on Twitter, where he goes by the handle @TMFUltraLong.

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