A lawyer said a New Jersey appeals court granted class-action status for certain plaintiffs in their claims against Merck ( MRK) over its arthritis drug Vioxx.

Chris Seeger, the lead attorney for a union health plan that's suing Merck, said Friday in a prepared statement that the decision enables certain plaintiffs' nationwide to join in litigation against the Whitehouse Station, N.J., drugmaker.

His firm, Seeger Weiss LLP, represents the International Union of Operating Engineers Local #68 Welfare Fund.

By midafternoon, Merck's stock lost 43 cents, or 1.2%, to $35.18.

Seeger said the appellate court decision, upholding a previous trial court ruling, would enable all nongovernmental health plans -- insurers, unions and large employers -- to consolidate their claims against Merck. Plaintiffs, he said, want to be reimbursed for their expenditures to make Vioxx available to their health-plan members. If they win the case, they could be entitled to triple damages under New Jersey law.

Merck had appealed the earlier trial court ruling, saying the "class was improperly certified." Merck says it will now appeal the ruling from the appeals court.

The company withdrew Vioxx from the market in September 2004 after clinical trials showed an increased cardiovascular risk among people who took the drug for more than 18 months.

As of Dec. 31, Merck was cited as a defendant in roughly 190 class-action claims alleging Vioxx caused personal injury or economic damage. The company has been named in 9,650 individual personal-injury lawsuits in the U.S.

Merck has lost one personal-injury case, which it's appealing, and it has won two. Next week, closing arguments will begin in a New Jersey case involving two men who say Vioxx caused their heart attacks. The case is being closely watched because this is the first personal-injury trial involving plaintiffs who say they took Vioxx for more than 18 months.

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