Vioxx Risks Could Have Been Detected Earlier: Study

CHICAGO (Reuters) - Heart risks from taking Merck & Co Inc's painkiller Vioxx could have been detected more than three years before the company withdrew the drug from the market in September 2004, had the data been openly available, U.S. researchers said on Monday.

They said their analysis illustrates the need for quick, public disclosure of drug safety data.

"You could have known there were marked safety problems with Vioxx as early as 2000 and the signal only grew stronger," said Dr. Harlan Krumholz of Yale University School of Medicine, who worked on the study published in the Archives of Internal Medicine.

Merck voluntarily withdrew Vioxx from the market in September 2004 after a clinical trial found the blockbuster drug increased the risk of heart attacks and strokes in long-term users of the medicine.

In November 2007, Merck signed a $4.85 billion deal to settle thousands of claims for heart attacks, strokes and deaths allegedly caused by the drug.

The study draws on company data from more than 30 clinical trials conducted by Merck between 1996 and 2004 comparing Vioxx, or rofecoxib, to a placebo or dummy pill.

Krumholz gained access to the data through his role as a paid witness for plaintiffs in lawsuits involving heart attacks or strokes that occurred after taking the drug.

"Most of the information we are using in this study was never published, or if it was published, they never included the key safety data," he said.

Of the 30 studies, 18 were published before September 2004, when the drug was withdrawn, six were published after that, and six were never published.

"We're suggesting this has to change," Krumholz said.

The team pooled data from randomized clinical trials that compared Vioxx to a placebo.

They pooled the trials in the order the studies were done, and after each one, they analyzed the data to see if they could detect any signal that would suggest the drug was raising the risk of heart attacks and strokes.