UPDATE 2-Alpharma reports positive Embeda pain drug data

(adds background on King bid)

By Toni Clarke

BOSTON, Sept. 9 (Reuters) - Alpharma Inc ALO.N, which is fighting off a $1.4 billion takeover bid from King Pharmaceuticals Inc (KG.N) said on Tuesday that its experimental pain drug Embeda significantly reduced pain due to osteoarthritis of the hip or knee.

Data presented at the annual meeting of the American Academy of pain management, showed that patients who took Embeda capsules reported significantly more pain relief, as measured by a change in a standard pain measure, than those who took a placebo over a 12-week period.

The results are being closely watched as they could affect Alpharma's value and negotiating power with King.

Alpharma, which makes the pain drug Kadian and pain patch Flector, as well as products to treat animals, last month rejected King's offer, but said it would seriously consider any "bona fide proposal that reflected the fair value of the company."

Alpharma said results of the Embeda trial showed that 72.5 percent of patients reported taking Embeda experienced pain relief of at least 30 percent from where they started, compared with 57.8 percent of patients given a placebo.

Earlier this month, Alpharma said that the U.S. Food and Drug Administration had agreed to give the drug a priority review, meaning a decision on whether to approve the product will be made within six months of application. The application was submitted on June 30, 2008.

Embeda is an extended-release opioid painkiller designed to treat moderate to severe chronic pain. It also is designed to deter the kind of abuse seen with other opioid drugs such as oxycodone.

King is eager to expand its presence in the pain drug market as sales of its blood pressure drug Altace reel from the impact of generic rivals. King is hoping to cut costs by combining the companies' sales forces, which would mean King would not have to hire more representatives to launch its experimental pain drug Remoxy.

Alpharma's shares closed down 76 cents, or 2 percent, at $34.26 on the New York Stock Exchange. (Editing by Andre Grenon and Carol Bishopric)