The top after-market Nasdaq gainers Tuesday were AeroVironment Inc, Anthera Pharmaceuticals Inc, Zogenix Inc, United Therapeutics Corporation and Orexigen Therapeutics Inc.

The top after-market Nasdaq losers were: Omeros Corporation, O'Reilly Automotive Inc, Medivation Inc, IAC/InterActiveCorp and Alexza Pharmaceuticals Inc.

Gainers

AeroVironment Inc (AVAV) shares climbed 9.08 percent to $27.75 in after-hours trading. Company announced that it expects to generate revenue of $348-$370 million and earnings per share (EPS) of $1.41-$1.51 better than analysts' expectation $349 million and EPS of $1.44 for fiscal 2013.

Shares of Anthera Pharmaceuticals Inc. (ANTH) rose 5.08 percent in post-market session to close at $3.10. Anthera Pharmaceuticals is a development-stage biopharmaceutical company. The company shares have a 52-week low of $1.44, a 52-week high of $8.78 and $121.19 million in market capitalization.

Zogenix Inc (ZGNX) shares advanced 3.66 percent to $2.55 in post-market trading. Its shares have a 52-week low of $1.31, a 52-week high of $5.11 and $160.82 million in market capitalization.

United Therapeutics Corporation (UTHR) shares surged 2.72 percent to $49.42 in after-hours trading Tuesday. The biotechnology company's shares have a 52-week low of $36.55, a 52-week high of $59.40 and $2.58 billion in market capitalization.

Orexigen Therapeutics Inc (OREX) shares gained 2.69 percent and reached $4.20 in after-hours trading.

Losers

Omeros Corporation (OMER) slumped 14.34 percent to $11.35 in post-market session Tuesday. The clinical-stage biopharmaceutical company on Tuesday announced its plans to offer shares of its common stock in a registered underwritten public offering.

O'Reilly Automotive Inc (ORLY) shares plunged 8.75 percent to $88.00 in post-market session. The company on late Tuesday cut its second quarter same-store sales outlook and said its earnings per share for the second quarter would be in the lower end of the previously announced range of $1.13 to $1.17.

Medivation Inc (MDVN) shares lost 2.32 percent in after-hours trading to reach $84.55. Its shares gained 2.38 percent in regular market trading.

IAC/InterActiveCorp (IACI) stocks dropped 2.27 percent to $44.39 in after-hours trading. The Internet business company stocks have a 52-week low of $34.12, a 52-week high of $52.78 and $3.71 billion in market capitalization.

Alexza Pharmaceuticals Inc. (ALXA) shares declined 2.10 percent to $4.20 in after-hours trading, company shares lost 7.14 percent in regular trading session. The pharmaceutical company has a 52-week low of $0.34, a 52-week high of $19.10 and a market capitalization of 50.87 million.

California