) -- Shares of



tumbled in late trades on Friday after the Federal Trade Commission said it's suing to block the hostile takeover of the company by




In a

statement on its Web site

, the FTC said its complaint against the deal alleges "the combination of the two largest U.S. long-term care pharmacies would harm competition and enable Omnicare to raise the price of drugs for Medicare Part D consumers and others."

Shares of PharMerica were last quoted at $12.25, down 14.3%, on volume of more than 215,000, according to

. Based on Friday's regular-session close at $14.30, the stock was up nearly 30% in the past year, hitting a 52-week high of $16.15 on Nov. 8.

Earlier Friday, Omnicare, whose stock was off 1.4% in the extended session, announced it had extended its tender offer to purchase all outstanding shares of PharMerica for $15 each until Feb. 17. PharMerica has said in the past that Omnicare's bid undervalues the company and advised shareholders not to tender their holdings to the tender offer. Omnicare said that as of Thursday, roughly 4.7 million PharMerica shares had been tendered to the offer, roughly 16% of the company's outstanding stock.

Omnicare first revealed its offer to buy PharMerica for $15 per share in late August, In a press release at that time, Omnicare said the all-cash bid was worth a total of $716 million, including assumption of debt, and that the consideration represented a premium of more than 35% to the previous session's closing price.

"If Omnicare is allowed to purchase its biggest and only national competitor, it will diminish competition and raise health care costs -- leaving taxpayers and patients to foot the bill," said Richard Feinstein, Director of the FTC's Bureau of Competition, in a statement. "The Bureau will continue to be vigilant in our efforts to prevent these sorts of anticompetitive deals."

Amylin Pharmaceuticals

Amylin Pharmaceuticals

( AMLN) was a big mover to the upside in the extended session on Friday after the company

received U.S. regulatory approval for its diabetes drug


The stock was last quoted at $14.20, up 17%, on volume of 4.22 million, according to

. Based on Friday's regular-session close at $12.14, the shares were down nearly 30% in the past year, scraping a 52-week low of $8.03 on Oct. 4.

The company said Bydureon received approval as a once-a-week treatment for type 2 diabetes from the

Food and Drug Administration

, and it expects the drug to be available in pharmacies in February.

The news also gave a lift to shares of


(ALKS) - Get Report

, which will receive a royalty on sales of the drug since Bydureon uses its injection technology. Alkermes' shares were last quoted at $19.99, up 4.7%, on volume of less than 200,000.


Written by Michael Baron in New York.

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Michael Baron


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