The 10 biotech and drug stocks with the largest short interest as percentage of float, according to S&P CapitalIQ:

10. Spectrum Pharmaceuticals (SPPI) - Get Report (26.8% shares short)



^NBI data by YCharts

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9. Dendreon (DNDN) (29.6% shares short)


DNDN data by YCharts

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8. Achillion Pharma (ACHN) - Get Report (29.7% shares short)


^NBI data by YCharts

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7. Arena Pharmaceuticals (ARNA) - Get Report (29.9% shares short)


ARNA data by YCharts

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6. Ziopharm (ZIOP) - Get Report (30.9% shares short)


ZIOP data by YCharts

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5. Intrexon (XON) - Get Report (32.8% shares short)


XON data by YCharts

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4. Idenix Pharma (IDIX) (33.3% shares short)


IDIX data by YCharts

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3. Synta Pharma (SNTA) (36.4% shares short)


SNTA data by YCharts

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2. Sarepta Therapeutics (SRPT) - Get Report (39% shares short)


SRPT data by YCharts

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1. Myriad Genetics (MYGN) - Get Report (52.4% shares short)


MYGN data by YCharts

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