The top pre-market NASDAQ Stock Market gainers are: Orchid Cellmark, Westport Innovations, Golar LNG, Hansen Medical, and Immunomedics. The top pre-market NASDAQ Stock Market losers are: American Superconductor, Randgold Resources, Optimer Pharmaceuticals, ASML Holding, and A-Power Energy Generation Systems.

Gainers

Orchid Cellmark Inc. (ORCH) stock jumped 39.30 percent to $2.80 in the pre-market trading. Laboratory Corp. of America Holdings (LH), or LabCorp, and Orchid Cellmark announced they have entered into a definitive agreement and plan of merger under which LabCorp will acquire all of the outstanding shares of Orchid Cellmark in a cash tender offer for $2.80 a share for a total purchase price to stockholders and optionholders of around $85.4 million.

As per the terms of the agreement and plan of merger, LabCorp has formed an acquisition subsidiary, OCM Acquisition Corp., that will commence a tender offer to buy all outstanding shares of Orchid Cellmark for $2.80 a share. The acquisition is expected to close in the second quarter of 2011.

Westport Innovations Inc. (WPRT) stock grew 5.78 percent to $27.08 in the pre-market trading. The company said Heckmann Corp. is teaming up with Encana Natural Gas Inc., a subsidiary of Encana Corp., Westport and Peterbilt Motors Co., a division of PACCAR Inc., to transition its truck fleet from traditional diesel vehicles to natural gas vehicles (NGVs).

Under the terms of the agreement, Encana will make fueling services available where Heckmann Water Resources (HWR) operates its fleet of water transportation vehicles. HWR will use the trucks to service its customer's natural gas wells and provide water handling services in conjunction with its system of pipelines and disposal wells.

HWR has issued a purchase order for 200 Peterbilt 367 liquefied natural gas (LNG) trucks incorporating Westport Heavy Duty Systems (Westport HD), from Westport. Although the purchase price of NGVs is higher than diesel trucks, the significantly reduced life cycle operating cost of NGVs is conducive to operating the heavy-duty trucks on natural gas. Additionally, because of cleaner combustion, the average operating life of NGVs is considerably longer.

Golar LNG Ltd. (GLNG) stock gained 4.56 percent to $29.59 in the pre-market trading. Samsung Heavy Industries Company Ltd has signed a preliminary deal worth $800 million to build four liquefied natural gas (LNG) carriers for Golar LNG , a Reuters report stated citing sources familiar with the matter.

Hansen Medical, Inc. (HNSN) stock increased 4.10 percent to $2.54 in the pre-market trading.

Immunomedics Inc. (IMMU) stock rose 3.79 percent to $4.11 in the pre-market trading. The company reported results that indicate immunoPET with TF2 and a gallium-68 (68Ga)-labeled peptide is a highly specific and sensitive imaging method for colon cancer. Results from this pretargeted study were presented at the 102nd annual meeting of the American Association for Cancer Research.

TF2 is a new generation of bispecific antibodies constructed using the Company's patented Dock-and-Lock (DNL) protein engineering platform technology. It specifically targets the carcinoembryonic antigen (CEA or CEACAM5) expressed in many human cancers, including colorectal cancer. Unlike conventional antibodies which can only attach to one receptor, TF2 has been modified to contain an additional binding site that recognizes a radioisotope-carrying peptide.

Losers

American Superconductor Corp. (AMSC) stock plunged 46.54 percent to $13.30 in the pre-market trading, as it guided fourth quarter loss due to refusal by Sinovel Wind Group Co. to accept contracted shipments. On March 31, Sinovel Wind Group refused to accept contracted shipments of 1.5 megawatt and 3 megawatt wind turbine core electrical components and spare parts that American Superconductor was prepared to deliver.

The company expects fourth quarter revenue to be less than $42 million and that it will generate a net loss on both a GAAP and non-GAAP basis. Street analysts predict profit of 33 cents a share on revenue of $119.13 million.

American Superconductor lowered its full year 2010 revenue guidance to less than $355 million from previous forecast of $430 million to $440 million. The company now expects earnings to be well below its previous guidance of $0.99 to $1.04 a share, and adjusted earnings to be well below its previous forecast of $1.33 to $1.38 a share. Analysts currently predict profit of $1.33 a share on revenue of $431.95 million.

AMSC continues to have active discussions with Sinovel to determine when Sinovel will accept further shipments and when it will pay for past shipments. In the meantime, AMSC has taken certain actions to reduce expenses, and the company is in the process of implementing plans to better align spending with near-term revenues while continuing to maintain a high level of service and support for its global Wind and Grid customers.

Randgold Resources Ltd. (GOLD) stock declined 1.53 percent to $86.50 in the pre-market trading. Spot gold posted a fresh record high of $1,457.85 a troy ounce, which was helping support the mining stocks in Europe. At 1005 GMT, gold was at $1,457.48, up from $1454.90 at the close in New York settlement Tuesday.

Optimer Pharmaceuticals, Inc. (OPTR) stock slid 1.09 percent to $13.65 in the pre-market trading. The company said the U.S. Food and Drug Administration's Anti-Infective Drugs Advisory Committee has recommended approval of the company's investigational antibiotic Dificid for the treatment of patients with Clostridium difficile infection, a bacterial infection in the lining of the gut that can cause severe diarrhea, colitis and in some cases death.

In a unanimous 13-0 decision, the Committee found that the clinical evidence submitted by Optimer showed the safety and effectiveness of Dificid for the treatment of Clostridium difficile infection. Optimer submitted its New Drug Application for Dificid on November 30, 2010. The FDA accepted the NDA filing and granted a six-month Priority Review in January, assigning a Prescription Drug User Fee Act goal date of May 30. The FDA is not bound by the committee's advice but takes it into consideration while approving a drug.

Separately, Optimer Pharmaceuticals said it has entered an exclusive two-year co-promotion agreement with Cubist Pharmaceuticals, Inc. (CBST) to market Dificid, in the U.S. Dificid, or fidaxomicin is a novel antibiotic currently being reviewed for market approval by the FDA for the treatment of Clostridium difficile infection, which is also known as Clostridium difficile-associated diarrhea.

Optimer and Cubist will co-promote Dificid to physicians, hospitals, long-term care facilities and other healthcare institutions in the US. The agreement expires two years from the first commercial sale of Dificid. Optimer is expected to be responsible for the manufacturing and distribution of Dificid in the US and for recording product revenue. Cubist will receive quarterly service fees of $3.75 million over the two years beginning with the first commercial sale of Dificid. Cubist is also eligible to receive an additional $5 million in the first year after first commercial sale and $12.5 million in the second year of the agreement.

ASML Holding NV (ASML) stock moved down 0.90 percent to $44.03 in the pre-market trading.

A-Power Energy Generation Systems, Ltd. (APWR) stock moved down 0.71 percent to $4.22 in the pre-market trading.

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