Merck & Co. (search) forced one of its researchers to remove her name from a study linking Vioxx (search) to heart attacks, then criticized the findings before ultimately pulling the arthritis drug from the market last fall, two of the scientist's colleagues said.

"Even after funding and agreeing with the design of the study, Merck publicly discredited our findings," Drs. Daniel Solomon and Jerry Avorn of Boston's Brigham and Women's Hospital wrote in this week's Archives of Internal Medicine.

Merck spokeswoman Anita Larsen confirmed the company's action, saying Merck believed the study's conclusions "were not supported by the data." The incident came about six months before another study prompted the drugmaker to withdraw Vioxx.

The journal contains several studies about Vioxx and Celebrex (search), the once popular and heavily promoted painkillers advertised as stomach-friendly alternatives to aspirin. They are under congressional and regulatory scrutiny.

One new report echoes previous data suggesting that in some older patients the drugs might not offer as much protection as thought against gastrointestinal problems. A separate study suggests they have been over-prescribed, frequently to patients at low risk for GI problems. And other research supports evidence that Vioxx increases some patients' blood pressure.

Vioxx was withdrawn Sept. 30 because of a study suggesting it doubled the risk of heart attack and stroke. Celebrex maker Pfizer Inc. halted its ads last month after a study linked high doses with increased heart and stroke risks.

Both drugs are in a class called Cox-2 inhibitors (search). The Archives reports, published Monday, come just weeks before a Feb. 16-18 Food and Drug Administration meeting on the safety of all Cox-2 drugs. Also Monday, the watchdog group Public Citizen petitioned the FDA to immediately remove from the market Celebrex and a related drug, Bextra, because of the potential heart risks.

Critics contend Merck attempted for years to suppress Vioxx risks found in numerous studies. The company maintains it has acted responsibly.

The author-removal incident, mentioned in previous news reports, involved a Merck study of more than 50,000 patients age 65 and older taking Vioxx, Celebrex, traditional painkillers or none of the drugs. The results, published last year in the journal Circulation, showed Vioxx patients faced a higher heart attack risk than the other groups.

When the results came in, "Merck required a co-author who was an employee of the company to remove her name from the article immediately prior to publication," Solomon and Avorn said in an Archives editorial.

Solomon identified the co-author as Merck epidemiologist Carolyn Cannuscio. She did not respond to e-mail and telephone requests for comment.

Larsen said publication policies at Circulation and Merck allowed the drugmaker to remove the employee's name "if the authors draw conclusions that are not supported by the data." She said Cannuscio agreed with Merck's decision.

Meanwhile, the British medical journal is releasing a study on the heart dangers of Vioxx after withholding the report because the researcher said he had been threatened by his superiors at the FDA.

The study links Vioxx to between 88,000 and 140,000 excess cases of heart disease in the United States — a conclusion that has previously been disclosed.

Dr. David Graham, who works in the FDA's office of drug safety, claimed he was threatened with dismissal and said he asked the Lancet to withdraw the paper from publication in November. Earlier this month, the FDA agreed the study could be published.