Updated from 3:19 p.m. EST

Pfizer

(PFE) - Get Report

was hit by a lawsuit alleging its arthritis and pain reliever drug Bextra was responsible for the death of a 46-year-old New Jersey man who used the drug for nine months.

It's unclear if the lawsuit, filed in a New York state court, is the first of its kind against Bextra.

The suit claims that "Pfizer has not acted responsibly and has failed to adequately and timely warn consumers about the life-threatening side effects associated with Bextra," according to a statement by the two laws firms that filed the suit.

Bextra has recently drawn attention because of possible side effects, including a rare but potentially fatal skin rash, as well as some research that says Bextra patients undergoing cardiac bypass surgery had a higher risk of heart-related complications. However, Bextra is not approved in the U.S. in any surgery-related care.

Pfizer has released research showing that there are no increases in cardiovascular risks among patients who took Bextra for between six weeks and 52 weeks.

The press release issued by the two law firms did not describe the alleged victim's overall health or whether he had undergone surgery.

However, the attorneys cited a report last week by researchers at an American Heart Association conference in New Orleans that people taking Bextra had a 2.19 times greater risk of heart attacks and strokes compared with people who took placebos.

Pfizer has previously said that research "draws unsubstantiated conclusions about the cardiovascular safety" of Bextra and "is based on information that has not been published in a medical journal or subject to independent scientific review." The cardiologist who presented the study was quoted by

The New York Times

as saying Bextra "is a time bomb waiting to go off." The researcher said the "magnitude of the signal with Bextra is even higher than what we saw in Vioxx."

The lawsuit against Pfizer comes amid a wave product liability lawsuits filed against

Merck

(MRK) - Get Report

following its recall of its arthritis drug Vioxx on Sept. 30. Both Vioxx and Bextra belong to the same class of drugs called COX-2 inhibitors.

Pfizer reported on Oct. 15 that it would conduct long-term tests on Bextra's cardiovascular effects. Two clinical trials involving heart bypass-surgery patients show that Bextra was linked to a greater risk of heart-related side-effects. The studies showed the risk existed among patients who took Bextra alone or in conjunction with an experimental COX-2 drug. Pfizer has since said that the increased risk was not statistically significant for heart bypass patients receiving only Bextra.

Pfizer also is negotiating with the Food and Drug Administration for a tougher label on Bextra, which has been linked to the rare skin rash called Stevens-Johnson Syndrome. The company said in a recent filing with the

Securities and Exchange Commission

that a revised Bextra label "likely will include the addition of a black-box" warning about the skin disease. The black box warning is the FDA's strongest warning. The current Bextra label alerts doctors and patients to this side-effect. This warning was inserted in 2002, a year after Bextra was approved by the FDA.

Ever since Merck pulled Vioxx from the market, Pfizer has released several studies showing no cardiovascular risk for Celebrex, its best-selling COX-2 drug. Pfizer recently said it would conduct tests assessing the long-term cardiovascular impact of Celebrex.

Pfizer's stock lost 27 cents, or 1%, to $27.35, just above its 52-week low of $27.02