The U.S. drugmaker pleaded guilty in recent months to having illegally promoted Vioxx for treatment of rheumatoid arthritis before it was approved for that use in 2002. The pill, approved in 1999 as a painkiller, was withdrawn from the market in 2004 after it was linked to risk of heart attack and stroke.

Federal prosecutors in Boston said Merck illegally promoted Vioxx for rheumatoid arthritis for three years, continuing to do so after being reprimanded in September 2001 by the U.S. Food and Drug Administration.

In a related settlement reached in November, Merck agreed to pay more than $600 million to the federal government, 43 states and the District of Columbia for a wider range of alleged improprieties. But it did not acknowledge any wrongdoing in the civil settlement.

The Department of Justice on Thursday said the settlement involved allegations that Merck made misleading statements about Vioxx's heart safety to boost sales of the medicine, and that it prematurely promoted the drug for rheumatoid arthritis.

(Reporting By Ransdell Pierson; Editing by Steve Orlosky)

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