GlaxoSmithKline

Shares of Human Genome Sciences surged on Thursday, nearly doubling after the company rejected an unsolicited buyout bid worth $2.6 billion in cash from GlaxoSmithKline .

On the news, the NYSE Arca Biotech Index is having its best day since December 2010.

Among the best performing stocks in the index, Gilead Sciences stock rose after one of its drugs showed positive results from a key hepatitis-C study.

NYSE Arca Biotech Index

TICKERCOMPANYPRICECHANGE%CHANGE
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GILDGilead Sciences Inc67.72-0.14-0.21%
INCYIncyte Corp57.10+0.24+0.42%
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