Merck & Co's board of directors said yesterday that a 20-month independent investigation - funded to the tune of $21 million by the company - found that its senior management acted responsibly in the development and marketing of its withdrawn painkiller Vioxx.

Merck pulled Vioxx (rofecoxib) off the market two years ago after data from the VIGOR study showed that it doubled the risk of heart attacks and strokes in patients taking the drug for 18 months or more.

John Martin, a former US judge who is now an attorney at law firm Debevoise & Plimpton and led the investigation, said in the just-published report that Merck had studied the drug adequately before launching it in 1999. It also said the firm did not mislead the US Food and Drug Administration about the findings of the VIGOR trial, which was published in the New England Journal of Medicine in 2000.

Last year, the journal’s editors criticised the study, saying that Merck had failed to include three cases of heart attack in its write-up, and had deleted other pertinent data shortly before submitting the manuscript for publication

The company now faces around 16,000 lawsuits from plaintiffs claiming injury from Vioxx and that Merck knew of the drug’s risks and recklessly sold it to the public. Merck, which has to date has won four lawsuits and lost four, has set aside a $1 billion warchest and has pledged to first each lawsuit individually, rather than enter into any form of group settlement.

But it is unclear what impact, if any, the new report will have on Merck’s legal footing in future Vioxx cases, particularly as it was paid for by the drugmaker.

Although largely supportive of Merck position, the report does run counter to the drugmaker's stance on some issues – particularly suggesting that data from another study – APPROVe – possibly indicates that use of Vioxx for less than 18 months could also increase the risk of heart attack. Unblinding of the APPROVe data in 2004 was the prompt for Merck to pull Vioxx from the market.

“Our investigation did find instances of poor judgement and errors, but it is important to note that they were not made with intent to deceive,” said Judge Martin.

The report is available here: