Benzinga's Top #PreMarket Gainers

J. C. Penney Company, Inc.JCP shares jumped 20.88% to $7.93 in pre-market trading on strong holiday sales. J. C. Penney reported a 3.7% y/y rise in its holiday comparable store sales. The company also announced that it now projects to report Q4 comparable store sales at the upper end of its prior outlook range of 2% to 4%. The Greenbrier Companies, Inc.GBX shares rose 9.51% to $54.00 in pre-market trading after the company reported better-than-expected earnings for its first fiscal quarter and raised its earnings forecast for FY 2015. Sonic Corp. SONC shares surged 7.53% to $29.13 in pre-market trading after the company announced upbeat results for its first fiscal quarter. Alkermes plc ALKS shares jumped 5.86% to $64.50 in pre-market trading after the company announced positive topline results from Phase 2 study. Arena Pharmaceuticals, Inc.ARNA shares gained 5.42% to $3.50 in the pre-market trading session after the company reported positive results from Phase 1b clinical trial evaluating APD334.