The top after-market NASDAQ stock market gainers are: OmniVision Technologies, United Online, BioCryst Pharmaceuticals, True Religion Apparel, and Questcor Pharmaceuticals. The top after-market NASDAQ stock market losers are: NutriSystem, MedAssets, Novatel Wireless, ViroPharma, and Metabolix.

Gainers

OmniVision Technologies Inc. (OVTI) stock jumped 14.68 percent to $27.35 in the after-market trading, as it guided fourth quarter earnings and revenue above Street view. The company expects fourth quarter adjusted earnings of 57 cents to 70 cents a share and revenue of $240 million to $260 million, while Street predicts profit of 44 cents a share on revenue of $217.18 million.

OmniVision reported third quarter adjusted profit of $50.99 million or 84 cents a share, up from $10.84 million or 20 cents a share last year. Revenue rose to $265.7 million from $156.9 million. Analysts had expected profit of 58 cents a share on revenue of $241.74 million.

Shares of United Online, Inc. (UNTD) climbed 11 percent to $6.76 in the after-hours trading.

BioCryst Pharmaceuticals, Inc. (BCRX) stock advanced 10.28 percent to $4.40 in the after-market session, as it received additional $55 million from the U.S. Department of Health & Human Services (HHS) to complete Phase 3 development of its neuraminidase inhibitor, intravenous peramivir, for the treatment of patients hospitalized with influenza.

This contract modification brings the total award from HHS to $234.8 million, providing funding through completion of Phase 3 development and the filing of a new drug application for intravenous peramivir in the U.S. It also extends the contract term by 24 months through December 31, 2013.

Shares of True Religion Apparel Inc. (TRLG) grew 8.02 percent to $22.75 in the after-hours session, as its fourth quarter earnings exceeded Street view. Profit was $15.8 million or 63 cents a share, up from $14.6 million or 59 cents a share last year. Sales rose 19.5 percent to $110.9 million. Analysts had expected profit of 61 cents a share on revenue of $103.4 million. The company expects full year 2011 earnings of $1.80 a share and sales of $405 million, while Street predicts profit of $2.02 a share on revenue of $406.83 million.

Questcor Pharmaceuticals, Inc. (QCOR) stock gained 7.45 percent to $13.42 in the after-market trading.

Losers

Shares of NutriSystem Inc. (NTRI) plunged 27.72 percent to $14.60 in the after-hours trading, as it posted weak fourth quarter revenue and said its results will continue to be hit by competitive pressures through 2011. The disappointing results in January and continued expected competitive challenges have caused the company to forecast 2011 revenues and profitability below 2010 levels.

NutriSystem still expects a profitable year in 2011, with earnings of 40 cents to 50 cents a share and positive adjusted EBITDA. In the first quarter, the company said reduced revenues, margin pressure, and one-time charges, including severance, will result in a forecasted first quarter loss of 30 cents to 35 cents a share. Street analysts predict profit of 30 cents a share for the first quarter and $1.32 a share for fiscal 2011.

NutriSystem posted fourth quarter earnings from continuing operations of $7.08 million or 25 cents a share, up from $5.79 million or 19 cents a share last year. Revenue declined to $87.86 million from $105.45 million. Analysts had expected profit of 25 cents a share on revenue of $100.64 million.

MedAssets, Inc. (MDAS) stock plummeted 13.23 percent to $18.50 in the after-market session, as it guided fiscal 2011 earnings and revenue below Street view. The company expects fiscal 2011 adjusted cash earnings of $0.94 to $1.04 a share and adjusted acquisition-affected revenue of $588 million to $602 million, while Street predicts profit of $1.14 a share on revenue of $626.20 million.

MedAssets reported fourth quarter loss of $49.4 million or or $0.87 a share, compared to a profit of $10.0 million or $0.17 a share last year. Adjusted cash earnings were $0.18 a share, down from $0.28 a share. Revenue rose to $107.0 million from $95.7 million, while adjusted revenue grew to $120.4 million from $95.7 million. Analysts had expected profit of 22 cents a share on revenue of $122.17 million.

Shares of Novatel Wireless Inc. (NVTL) fell 12.76 percent to $5.88 in the after-hours session, as it guided first quarter loss wider than Street view. The company expects first quarter adjusted loss of 36 cents to 48 cents a share and revenue of $60 million to $80 million, while Street predicts loss of 3 cents a share on revenue of $101.90 million.

Novatel posted fourth quarter adjusted earnings of $32,000 or breakeven a share, down from $2.3 million or 7 cents a share last year. Revenue rose to $119.27 million from $88.63 million. Analysts had expected profit of 1 cent a share on revenue of $114.68 million.

ViroPharma Inc. (VPHM) stock tumbled 11.63 percent to $14.52 in the after-market trading. Profit for the fourth quarter was $37.47 million or 43 cents a share, up from $12.01 million or 15 cents a share last year. Adjusted earnings grew to $45.62 million from $20.81 million. Product sales rose to $121.62 million from $87.84 million. Analysts had expected profit of 31 cents a share on revenue of $114.22 million.

ViroPharma reiterated its fiscal 2011 guidance, expecting net Cinryze sales to be $235 million to $260 million. In addition, research and development and selling, general and administrative expenses are expected to be $170 million to $190 million.

Shares of Metabolix, Inc. (MBLX) slid 8.86 percent to $8.43 in the after-hours trading.