The New England Journal of Medicine said it found that data about three Vioxx patients who had heart attacks were excluded from a Merck-sponsored study it published, resulting in an underestimation of the drug's cardiovascular risk.
The medical journal publicized its revelation Dec. 8 in an editorial titled "Expression of Concern," stating that the three missing myocardial infarctions, as well as other adverse event data that were omitted, represent "inaccuracies and deletions" that "call into question the integrity of the data on adverse cardiovascular events."
The study authors, two of whom are Merck employees, were asked to submit a correction, the Journal said.
The study--Merck's VIGOR (Vioxx Gastrointestinal Outcomes Research)--appeared in the journal in 2000. The study has been a centerpiece of evidence for plaintiff's attorneys in Vioxx litigation.
The editorial came as the jury in the third Vioxx trial heard closing arguments yesterday. The plaintiff in the case, Evelyn Erwin Plunkett, asserts that Vioxx caused the fatal heart attack of her husband, Richard "Dicky" Irvin, in 2001 after he took the drug for less than a month.
In a statement, Merck said VIGOR "fairly and accurately described the results of the study" and that the three heart attacks did not appear in the published paper because they occurred after a "pre-specified cutoff" date for analysis.
The firm added that "these additional events did not materially change" any of the article conclusions and that the data were
disclosed to the FDA in 2000, presented publicly at the FDA's Advisory Committee in 2001 and included in numerous Merck press releases since.
"Merck only recently learned of this editorial," the company concluded, and has "not had an opportunity to formally respond" to NEJM.
In its editorial, the Journal said that it learned late last month that at least two VIGOR authors knew about the omitted heart attacks in July 2000, more than four months before the article appeared. It did not name them. And a diskette submitted with the article showed some data were deleted from the manuscript two days before it was initially submitted to the Journal in May 2000, it said.
Merck withdrew Vioxx in September 2004 after data showed the drug increased heart attack risk among those taking it for more than 18 months.