Merck agrees to pay $4.85 billion in Vioxx settlement

"We believe that it provides a reasonable and responsible resolution of the litigation that provides us with a significant degree of certainly," Frazier said.

"I believe this global resolution is the best and fairest way to resolve this litigation," said Christopher Seeger, co-lead counsel for the plaintiffs in the federal litigation. "I will confidently recommend this settlement to my clients because it eliminates the risk attendant in litigation."

The drugmaker - whose shares rose 2.1 percent Friday despite a falling stock market - said it would take a charge of $4.85 billion to cover costs of the agreement.

Two of the key judges overseeing thousands of cases also expressed support for the settlement.

Mark Lanier, a plaintiff's lawyer who won the first Vioxx case to trial, told Reuters in an e-mail: "Merck needed to do this now because next year, litigation would explode. There would likely be upwards of 50 plaintiffs tried next year."

Since the withdrawal of Vioxx, Merck has won 11 court cases concerning the drug and lost five. The company has yet to pay any of the victorious plaintiffs while the cases go through appeals.