Shares of biotech Incyte came down hard today, after news that the company’s drug Jakafi may have weakened the immune system of one patient in the U.K. enough to allow a rare type of viral brain disease to take hold, which proved fatal. Will this be fatal for the stock as well? In this video, Motley Fool health-care analyst David Williamson gives investors some advice that may temper their panic a bit.

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The article Should Incyte Investors Be Panicked? originally appeared on Fool.com.

David Williamson has no position in any stocks mentioned. The Motley Fool recommends Gilead Sciences and Quest Diagnostics. Try any of our Foolish newsletter services free 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 a disclosure policy.

Copyright © 1995 – 2013 The Motley Fool, LLC. All rights reserved. The Motley Fool has a disclosure policy.

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