Biotech stocks were battered this week with the iShares Nasdaq Biotechnology ETF tumbling 1.8% on Friday for a weekly decline of 11%, its worst one-week performance since the end of September. Even with the Dow Jones Industrial Average and the S&P 500 both posting steep losses, biotech shares underperformed the broader market significantly. The sector, which had been one of the best performers during the bull market, has come under pressure after peaking in July, particularly after Hillary Clinton criticized drug companies on how they price specialty drugs.
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