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* AstraZeneca paying $12.70/share plus CVR worth up to $4.70
* Deal at 88 percent premium; Omthera shares at $12.80 inpremarket
* Fish oil-based drug builds up AstraZeneca's heart business
* AZ shares up 3.2 pct, helped by generic asthma drug delay
By Ben Hirschler
LONDON, May 28 (Reuters) - AstraZeneca is to buyOmthera Pharmaceuticals for as much as $443 million tobuild up its cardiovascular drug business, a priority area forBritain's second-biggest drugmaker.
The acquisition of the U.S.-based specialist in fishoil-derived medicine underscores a drive by new Chief ExecutivePascal Soriot to revive AstraZeneca's fortunes through a seriesof bolt-on deals.
It is his second purchase in the cardiovascular field,following the acquisition last month of AlphaCore Pharma, asmall early-stage U.S. biotechnology company.
The latest transaction pitches AstraZeneca into competitionwith rivals including GlaxoSmithKline that already sellheart-friendly fish oil drugs.
Omthera's leading drug has already completed final-stageclinical tests and has the potential to be combined withAstraZeneca's blockbuster cholesterol fighter Crestor. Helveaanalyst Odile Rundquist said the deal was "a good move as itperfectly complements AstraZeneca's cardiovascular portfolio".
AstraZeneca's sales and profits are falling as oldermedicines lose patent protection and the company badly needs newproducts to replace former big sellers like the antipsychoticSeroquel, which lost exclusivity last year.
AstraZeneca said on Tuesday it had entered into a definitiveagreement to buy Omthera for $12.70 per share, or approximately$323 million, a premium of 88 percent to Omthera's closing priceon Friday.
In addition, Omthera shareholders will get "contingent valuerights" (CVRs) of up to approximately $4.70 per share, or $120million in total, depending on the success of Omthera'sexperimental drug Epanova, for treating patients with very hightriglycerides, a type of blood fat that is bad for the heart.
CVRs are being used increasingly in deals in thepharmaceutical and biotechnology market to bridge differingexpectations surrounding new drugs whose final sales areuncertain.
Shares in Omthera leapt 90 percent to $12.80 in premarketdealings on Nasdaq.
SEEKING U.S. APPROVAL
Epanova is an ultra-pure mixture of the free fatty acidforms of eicosapentaenoic acid (EPA) and docosahexaenoic acid(DHA), derived from fish oil. It has already completedfinal-stage Phase III clinical trials and is set to be submittedfor U.S. regulatory approval around the middle of this year.
The new drug will compete with other fish oil-basedmedicines such as GlaxoSmithKline's Lovaza and Amarin's recently approved Vascepa. AstraZeneca had, at one stage, beentipped as a possible buyer of Amarin.
Lovaza last year generated sales of 607 million pounds ($917million) for GSK in the United States and Puerto Rico, where thecompany has marketing rights to the product.
Cardiovascular medicine is a key area for AstraZeneca, whosetop-selling drug is Crestor. The British-based group said itintended to conduct a series of clinical studies testing afixed-dose combination of Crestor and Epanova. The newcombination, if successful, would extend the Crestor franchisebeyond 2016, when the drug's U.S. patent ends.
AstraZeneca is also banking on another heart drug, Brilinta,to drive sales as older products go off patent.
Shares in AstraZeneca were up 3.2 percent at 3536.5 pence ina strong London stock market by 1054 GMT. In addition to news ofthe Omthera deal the stock was buoyed by news of a temporaryblockage on U.S. sales of rival generic versions of its asthmadrug Pulmicort Repsules, which was announced late on Friday.
The deal to buy Omthera has the backing of investorsrepresenting 60 percent of the Princeton, New Jersey-basedcompany's shares. It is expected to close in the third quarterof 2013.
