(AP) - TRENTON, N.J.-Vioxx users in the study that led to the painkiller being pulled from the market weren't at increased risk of heart attack or stroke in the year after stopping the drug, Merck & Co. said Thursday.

Merck said data from a "preliminary safety analysis" of an additional year of patient follow-up, part of the study's original plan, did not show a statistically significant difference in the rate of heart attacks and strokes among patients who had been on Vioxx and those who had taken a dummy pill. That means the differences over that year could have been due to chance.

However, the new data shows that in the 12 months after the study's three-year treatment phase, 28 patients who had been on Vioxx had heart attacks or strokes caused by blood clots, compared with 16 of the patients who had taken placebos. The difference was mainly because seven patients who had been on Vioxx suffered a stroke compared to none in the placebo group.

Merck general counsel Kenneth Frazier said the results will not change Merck's strategy of fighting, one by one, the many lawsuits filed by former Vioxx users and their families alleging the one-time blockbuster arthritis drug caused heart attacks, strokes and deaths.

"We believe that the data don't provide for a claim for a patient who had an event after they stopped taking their medicine," Frazier told reporters and analysts in a late-afternoon conference call.

Peter S. Kim, president of Merck Research Laboratories, said the findings were the same in the follow-up year whether patients took the Vioxx the entire three years of the study or stopped taking it early.

"These preliminary analyses have been shared with regulatory authorities" and Merck plans to publish them in a peer-reviewed medical journal, Kim said.

Kim said the death rates over the four years were similar for the Vioxx and placebo groups, but said he didn't have the figures available.

The Whitehouse Station-based pharmaceutical company released the information after the stock market closed Thursday. Shares closed at $34.51 on the New York Stock Exchange, down 16 cents and more than 25 percent lower than when Merck pulled Vioxx from the market in September 2004. That was after data from the first three years of the study showed Vioxx doubled risk of heart attack and stroke after 18 months' use.

Merck faces about 10,000 lawsuits over Vioxx, including numerous potential class-action suits, and has lost half of the six cases to come to trial so far.

In related news, a Vioxx case that was slated to begin July 31 in Tampa, Fla. was postponed on Wednesday at the request of both the plaintiff and Merck.

But sides said the necessary depositions wouldn't be done by the trial's start date.

The case centers around Refic Kuzic, a retired professional soccer player, who suffered a nonfatal heart in 2001 after taking Vioxx for about two and a half months.

The next Vioxx case is set to be heard in New Jersey on June 5. It initially involved two plaintiffs but last month Judge Carol Higbee ordered that the trial of John Klug be postponed because of concerns arising from his prescriber records.

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AP Business Writer Theresa Agovino in New York contributed to this story.

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