Shares of Cara Therapeutics Inc. plunged 27% in premarket trade Friday, after mixed results from a phase 2b trial of the biotechnology company's pain medication prompted a downgrade at Janney Montgomery Scott. Analyst Ken Trbovich cut his rating to neutral from buy, saying the results of the trial weren't strong enough to achieve statistical significance at the highest dose and did not show an effect at lower doses. The result of the trial "gives us less confidence in the outlook for a positive outcome for the phase 3 than we had previously," Trbovich wrote in a note to clients. The stock had nearly tripled year to date through Thursday, while the iShares Nasdaq Biotechnology ETF had rallied 18% and the S&P 500 had gained 8.1%.
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