The top after-market NASDAQ Stock Market gainers are: Amylin Pharmaceuticals, Alkermes, China Auto Logistic, Optimer Pharmaceuticals, and Vitacost.com. The top after-market NASDAQ Stock Market losers are: Ixia, SemiLEDs, Life Partners Holdings, Multi-Fineline Electronix, and DragonWave.

Gainers

Amylin Pharmaceuticals, Inc. (AMLN) stock jumped 11.67 percent to $15.31 in the after-market trading. The company and Alkermes Inc. (ALKS) announced positive results from a FDA-requested study regarding the new drug application for Bydureon, an investigational medication for type 2 diabetes. Amylin is in partnership with Eli Lilly and Co. (LLY) to develop and market Bydureon (exenatide extended-release for injectable suspension), based on a proprietary technology developed by Alkermes. Bydureon is currently approved in the European Union. Amylin said the results from the thorough QT (tQT) study assessed the potential of exenatide to increase the QT interval across a wide range of plasma concentrations. The study was in accordance with a FDA requirement for the Bydureon New Drug Application.

The QT interval refers to the time the heart's system takes to recharge after each beat. As prolongation of the QT interval may increase the risk for cardiac arrhythmias, the FDA requires a tQT study for most new drugs in development. According to Amylin, the QT study met its primary endpoint, with data showing that exenatide did not prolong the corrected QT (QTc) interval in healthy individuals. Further, the study found no relationship between QTc interval and plasma exenatide concentrations. Amylin, along with Eli Lilly and Alkermes, intends to submit results of the tQT study with the FDA in the third quarter of 2011. Bydureon is an investigational medication for type 2 diabetes designed to deliver continuous therapeutic levels of exenatide in a single weekly dose. The drug is a once-weekly formulation of exenatide, the active ingredient in Byetta (exenatide) injection available in the U.S. since June 2005 and used in more than 70 countries worldwide to treat type 2 diabetes.

Alkermes, Inc. (ALKS) stock grew 6.08 percent to $20.40 in the after-market trading. Shares of Amylin and Alkermes grew in the after-hours as diabetic drug Bydureon study meets endpoints.

China Auto Logistic Inc. (CALI) stock gained 3.86 percent to $2.15 in the after-market trading.

Optimer Pharmaceuticals, Inc. (OPTR) stock increased 3.23 percent to $12.45 in the after-market trading.

Vitacost.com, Inc. (VITC) stock rose 2.51 percent to $5.13 in the after-market trading. The company said it received a letter from the NASDAQ Stock Market indicating that the company has met the requirements for continued listing of the company’s securities on the NASDAQ Stock Market. We are pleased to announce that Vitacost.com is now in compliance with NASDAQ’s listing requirements. We worked closely with NASDAQ during the time of the trading suspension and with the conclusion of our Annual Meeting, held July 5th, we have now fulfilled the requirements to remain listed, said Jeffrey Horowitz, Vitacost.com’s Chief Executive Officer.

Losers

Ixia (XXIA) stock plunged 15.30 percent to $11.02 in the after-market trading. The company lowered its second quarter adjusted earnings guidance to range of $0.07 to $0.08 per share from previous forecast of $0.14 to $0.17 per share. The company also reduced revenue outlook to range of $67 million to $69 million from previous range of $78 million to $82 million. Street analysts predict profit of $0.16 per share on revenue of $80.54 million. The company said its second quarter revenue was impacted by several factors, including lower than expected revenue from Asia Pacific and from certain large equipment makers, as well as orders received late in the quarter that could not be fulfilled in the second quarter.

SemiLEDs Corp. (LEDS) stock plummeted 13.87 percent to $5.34 in the after-market trading. Adjusted loss for the third quarter was $4.3 million or $0.16 per share, compared to a profit of $3.3 million to $0.09 per share last year. Revenue fell 43 percent to $5.6 million. Analysts had expected a loss of $0.06 per share on revenue of $6.25 million. Looking ahead, the company expects fourth quarter loss of $0.23 to $0.25 per share and revenue of $5.5 million to $6.5 million, while Street predicts a loss of $0.02 per share on revenue of $9.02 million.

Life Partners Holdings, Inc. (LPHI) stock tumbled 10.45 percent to $3.60 in the after-market trading.

Multi-Fineline Electronix Inc. (MFLX) stock fell 9.80 percent to $19.60 in the after-market trading. The company lowered its third quarter sales guidance to about $191 million from previous forecast of $200 million to $220 million, while Street predicts $209.96 million. The company now projects gross margin of about 12 percent, compared to previous outlook of 12 percent to 13 percent.

DragonWave Inc. (DRWI) stock slid 5.38 percent to $5.45 in the after-market trading.