20 Stocks Moving In Wednesday's Pre-Market Session

Gainers

• Tetraphase Pharmaceuticals Inc TTPH shares rose 36.2 percent to $9.40 in pre-market trading as the company reported 'positive' topline Phase 3 IGNITE4 results. Stifel Nicolaus upgraded Tetraphase Pharma from Hold to Buy.
• EnteroMedics Inc ETRM shares rose 20.7 percent to $5.25 in pre-market trading as the company disclosed that it has entered into a collaboration agreement with Galvani Bioelectronics.
• iRobot Corporation IRBT rose 20.3 percent to $105.75 in pre-market trading after the company posted upbeat results for its second quarter and issued a strong FY17 forecast. iRobot also agreed to acquire privately-held Robopolis SAS.
• Ophthotech Corp OPHT rose 11.4 percent to $2.94 in pre-market trading after the company reported a narrower-than-expected Q2 loss. Ophthotech also disclosed that it has expanded its focus with development for ophthalmic orphan diseases.
• Tantech Holdings Ltd TANH rose 10.4 percent to $3.39 in pre-market trading as the company reported that it has obtained official approval for two updated EV models.
• Advanced Micro Devices, Inc. AMD rose 9.3 percent to $15.42 in pre-market trading after the company reported stronger-than-expected earnings for its second quarter.
• Smart & Final Stores Inc SFS rose 7.4 percent to $8.70 in pre-market trading. Smart & Final Stores posted Q2 adjusted earnings of $0.14 per share on revenue of 1.08 billion.
• EXACT Sciences Corporation EXAS rose 7.2 percent to $40.00 in pre-market trading after the company posted strong Q2 results and raised its FY17 guidance.
• United States Steel Corporation X shares rose 6.6 percent to $26.05 in pre-market trading on upbeat quarterly earnings.
• Sino-Global Shipping America, Ltd. SINO shares rose 6.6 percent to $3.30 in the pre-market trading session after declining 0.79 percent on Tuesday.
• LG Display Co Ltd. (ADR) LPL rose 4.2 percent to $15.09 in pre-market trading after declining 3.91 percent on Tuesday.

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Losers

• USANA Health Sciences, Inc. USNA fell 17.2 percent to $53.65 in pre-market trading after the company posted downbeat Q2 earnings and lowered its FY17 guidance.
• Compugen Ltd. (USA) CGEN shares fell 11.2 percent to $3.60 in pre-market trading after climbing 19.12 percent on Tuesday. Compugen issued an update for collaborative efforts with Bayer in immuno-oncology.
• Internet Gold Golden Lines Ltd IGLD fell 8.2 percent to $6.15 in pre-market trading after slipping 3.81 percent on Tuesday.
• Akamai Technologies, Inc. AKAM fell 7.5 percent to $49.31 in pre-market trading. Akamai posted upbeat results for its second quarter, but issued a weak forecast for the current quarter.
• Orion Engineered Carbons SA OEC fell 7.4 percent to $21.90 in pre-market trading. Orion Engineered reported a 10 million secondary offering.
• Moelis & Co MC fell 4.7 percent to $41.75 in pre-market trading. Moelis priced 6 million share offering at $42.00 per share.
• Wynn Resorts, Limited WYNN shares fell 4.3 percent to $133.00. Wynn Resorts reported Q2 adjusted earnings of $1.18 per share on sales of $1.53 billion. Telsey Advisory Group downgraded Wynn Resorts from Outperform to Market Perform.
• Chegg Inc CHGG shares rose 4.2 percent to $13.65 in pre-market trading. Chegg reported a Q2 loss of $6 million.
• BiondVax Pharmaceuticals Ltd (ADR) BVXV fell 3.6 percent to $9.88 in pre-market trading after dropping 1.63 percent on Tuesday.