A federal drug safety adviser said Friday the government rescinded his invitation to participate in a February meeting on the risk of Vioxx (search) and other arthritis drugs because he had already publicly expressed doubts about the medications.
"The reason was that I had expressed my views publicly," said Dr. Curt Furberg, a Wake Forest University School of Medicine professor of public health sciences.
This week, Furberg's analysis showing a doubling of risk of heart and stroke among heart disease patients taking Bextra (search) was discussed at the American Heart Association's annual meeting. Furberg was quoted as saying, "Basically, we showed that Bextra is no different than Vioxx, and Pfizer is trying to suppress that information."
On Thursday morning, when the agency was closed for the holiday, an FDA official called Furberg, a federal adviser on drug safety and risk management, to say he was no longer welcome at the February meeting.
The FDA did not immediately respond to a reporter's request for comment.
The remaining government advisers will discuss the safety of arthritis drugs in the same class as Vioxx after reviewing an avalanche of paper, including confidential unpublished trials and a first glimpse at long-term safety studies.
The FDA's arthritis advisory committee (search) members, other federal advisers and some the nation's leading rheumatologists have been asked to block out Feb. 16-17 for the session.
On Friday, Furberg said he did not protest the agency's action.
"I didn't ask why. I didn't ask who was behind it. I did nothing. I just accept it," he said. "I will say that I am probably more qualified than anyone else to comment on the study that I did. I think this study is very relevant. It has created a dark cloud over Bextra."
His removal from the panel was first reported by The Wall Street Journal.
The joint panel will be asked to answer a key question raised by doctors and patients: Do the same heart safety concerns that pushed Vioxx off the market apply to related painkillers?
"I don't know whether there is enough data available to say there is a class effect that would be appropriate to generalize to all cox-2 inhibitors about coronary artery disease. But that is what we are all concerned about," said Dr. Gary Stuart Hoffman, a member of the FDA arthritis advisory panel.
"It's possible that the committee will decide there isn't adequate data and additional studies or ongoing studies need to be continued," said Hoffman, chairman of rheumatic and immunologic diseases at the Cleveland Clinic Foundation.
The crucial issue, say leading cox-2 inhibitor researchers, is whether the new painkillers cause blood clots, which trigger heart attacks and strokes. Or do the drugs simply fail to prevent blood clots in people otherwise at risk for heart woes?
"I tell people often that in building a better ... nonsteroidal anti-inflammatory drug, we lost something in the mix. What we lost was the ability to thin the blood, which is what aspirin and like drugs used to do," said Dr. John Cush, another arthritis advisory committee member and chief of rheumatology and clinical immunology at Presbyterian Hospital in Dallas.
The panel also is expected to discuss whether it's ethical to give dummy pills to patients in pain. Placebo-controlled trials are the gold standard. An advisory panel considering a trial looking at a cox-2 inhibitor to treat gout in June dismissed placebos as unethical, even for a few weeks.
According to a presentation this week by the FDA's Office of New Drugs deputy director, government arthritis experts will review all available data about cox-2 inhibitors (search), including Vioxx, Bextra and Celebrex.
The data includes a placebo-controlled trial involving 3,600 patients that ponders whether Celebrex prevents colon polyps and another that tests the popular painkiller as a possible Alzheimer's treatment, according to Dr. Sandra Kweder's presentation.
Independent safety and monitoring boards for those two Celebrex studies are closely watching for any spike in heart attacks or strokes in the monthly data updates. So far, there has been no repeat of the doubling of risk of such cardiovascular woes that led Merck & Co. to withdraw Vioxx from the market.
In light of Furberg's preliminary study, submitted for publication, the federal advisers will also consider additional studies of that painkiller.
In a press release, Pfizer dismissed Furberg's study as "unsubstantiated conclusions" that had not been subjected to independent scientific review.
"With the information on Bextra, you really have to ask, 'Does this apply to all of them'?" Furberg said.