Benzinga's Top Pre-Market NASDAQ Gainers (RVBD, GTXI, USAT, SLGN)

Riverbed Technology Inc RVBD added 13.36% to $35.05 in the pre-market session. RVBD issued upbeat projections for the first quarter. GTx Inc GTXI moved up 8.36% to $2.98 in the pre-market session. Analysts at Citigroup upgraded GTXI from "hold" to "buy." USA Technologies Inc USAT rose 8.29% to $2.22 in the pre-market session. the USAT reported a 93% year-over-year surge in number of transactions processed for the month of March 2011. Silgan Holdings Inc SLGN soared 5.89% to $39 in the pre-market trading. SLGN agreed to purchase Graham Packaging GRM for about $4.1 billion, including debt. Read more from Benzinga's Markets.