The top after-market NASDAQ stock market gainers are: Novavax, Sonus Networks, SuperGen, Global Defense Technology & Systems, and SuperMedia. The top after-market NASDAQ stock market losers are: YRC Worldwide, Hickory Tech, Smith Micro Software, Exterran Partners, and VIVUS.

Gainers

Novavax, Inc. (NVAX) stock jumped 38.08 percent to $3.59 in the after-market trading, as it received a contract worth up to $97 million from the U.S. Department of Health and Human Services over three years to develop new flu vaccine technology. Novavax's contract can be extended for another two years, which would raise its total value by $82.1 million. Novavax has been asked to develop new technology to produce vaccines using insect cells to express influenza proteins and create virus-like particles that stimulate the immune system.

Separately, Novavax said it agreed to license its proprietary, recombinant virus-like-particle (VLP) vaccine technology to LG Life Sciences, Ltd. LG Life Sciences received an exclusive license to manufacture, develop and commercialize influenza vaccines using Novavax's recombinant VLP technology in South Korea. LG Life Sciences also received a non-exclusive license to manufacture, develop and commercialize influenza VLP vaccines in certain emerging market countries.

Sonus Networks, Inc. (SONS) stock climbed 29.37 percent to $3.92 in the after-hours trading, as it guided fiscal 2011 revenue above Street view. The company expects fiscal 2011 revenue of $265 million to $285 million, while Street predicts $257.44 million.

Sonus Networks posted fourth quarter earnings of $11.4 million or 4 cents a share, compared to $10.31 million or 4 cents a share last year. Results for the quarter include stock-based compensation of $2.87 million, compared to $2.92 million last year. Adjusted profit rose to $15 million from $13.3 million. Revenue rose to $82.98 million from $68.71 million. Analysts had expected a loss of 1 cent a share on revenue of $65.10 million.

SuperGen Inc. (SUPG) stock advanced 6.06 percent to $3.15 in the after-market trading, as its fourth quarter earnings and revenue exceeded Street view. Profit was $6.75 million or 11 cents a share, up from $2.34 million or 4 cents a share last year. Revenue rose to $15.28 million from $11.97 million. Analysts had expected profit of 4 cents a share on revenue of $14.10 million. SuperGen expects fiscal 2011 royalty revenue for Dacogen to increase up to 5 percent from last year to a range of $52 million to $55 million, and earnings of less than $14 million.

Global Defense Technology & Systems, Inc. (GTEC) stock gained 5.23 percent to $17.20 in the after-market trading.

SuperMedia Inc. (SPMD) stock increased 4.75 percent to $8.82 in the after-hours trading.

Losers

YRC Worldwide Inc. (YRCW) stock fell 8.96 percent to $2.44 in the after-market trading. During the intra-day trading the stock plunged 21.64 percent to $2.68, as it agreed in principle with certain of its lenders and other stakeholders to restructure the company. The company said the move could result in a very substantial dilution of existing equity holders.

YRC Worldwide said the agreement in the form of a non-binding term sheet involves conversion of some of the company's debt obligations into equity, which could significantly dilute the existing equity holders. The restructuring is envisaged to close by July 2011.

YRC said the agreement makes possible deferral of interest and fees under the company's credit agreement and ABS facility through the period that the restructuring is underway. YRC also said ts lenders waived the first quarter 2011 EBITDA covenant in view of the harsh winter and as part of an anticipated revision in forward covenants under the new restructuring plan.

Hickory Tech Corp. (HTCO) stock tumbled 4.51 percent to $9.75 in the after-hours trading. Fourth quarter earnings were $2.1 million or 16 cents a share, up from $1.4 million or 11 cents a share last year. Revenue rose 9 percent to $41.78 million. The company expects full year 2011 earnings of $7.4 million to $8.7 million and revenue of $158 million to $164 million.

Smith Micro Software Inc. (SMSI) stock slid 3.63 percent to $9.03 in the after-market trading.

Exterran Partners, L.P. (EXLP) stock declined 3.54 percent to $28.65 in the after-hours trading. Exterran Partners said it filed a preliminary prospectus supplement with the Securities and Exchange Commission relating to a proposed secondary offering of common units representing limited partner interests in Exterran Partners by Exterran Holdings Inc. (EXH).

Exterran Holdings intends to sell an aggregate of 5.25 million common units and grant the underwriters a 30-day option to purchase up to an aggregate of 787,500 additional common units to cover over-allotments, if any. Exterran Partners is not selling any common units in this offering and will not receive any proceeds from the sale of the common units by Exterran Holdings. Wells Fargo Securities, BofA Merrill Lynch, Barclays Capital, J.P. Morgan and RBC are acting as joint book-running managers.

VIVUS Inc. (VVUS) stock decreased 3.42 percent to $7.35 in the after-market trading. Loss from continuing operations for the fourth quarter widened to $19.12 million or 23 cents a share from $15.54 million or 19 cents a share last year. Net loss narrowed to $6.51 million or 8 cents a share from $13.21 million or 16 cents a share last year. Analysts had expected a loss of 22 cents a share.