Why Achillion Pharmaceuticals' Shares Popped

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 hepatitis-C focused company Achillion Pharmaceuticals (NAS: ACHN) is up 13% today, following the release of positive proof-of-concept data on drug hopeful, ACH-3102.

So what: Early-stage data released today suggests Achillion's ACH-3102, a non-nucleotide, protease-based inhibitor, showed statistically significant mean reduction in hepatitis-C virus levels in patients studied. The data was encouraging enough for the company to move forward with a stage 2a trial for patients with the difficult-to-treat genotype 1b form of the hepatitis-C virus.

Now what: I don't want to sound like a broken record, but betting on Achillion here is like leaving the baseball game in the third inning because your team is up four to one. There's still a lot of game left to be played. Achillion still has genotype 1b efficacy and safety issues to overcome, as well as myriad competitors. At the moment, Gilead Sciences (NAS: GILD) GS7977 is in line to garner the lion's share of the non-interferon based HCV treatment market, assuming its safety profile remains pristine. Bristol-Myers Squibb (NYS: BMY) and Idenix Pharmaceuticals (NAS: IDIX) haven't been nearly as lucky, with Bristol's BMS-986094 being completely discontinued due to safety issues, and Idenix having two trials halted indefinitely by the FDA while it investigates drug safety. I stand by my assessment of not being sold on Achillion's pipeline.

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The article Why Achillion Pharmaceuticals' Shares Popped originally appeared on Fool.com.

Fool contributorSean Williamshas no material interest in any companies mentioned in this article. You can follow him on CAPS under the screen nameTMFUltraLong, track every pick he makes under the screen nameTrackUltraLong, and check him out on Twitter, where he goes by the handle@TMFUltraLong.Motley Fool newsletter serviceshave recommended buying shares of Gilead Sciences. Try any of our Foolish newsletter servicesfree for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has adisclosure policy.

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