An independent panel that reviewed the safety of cox-2 painkillers for Health Canada is calling for the return of the controversial drug Vioxx -- and sounding an unexpected alarm about the heart risks of an old and popular pain reliever, ibuprofen.
The panel, a 13-member team of doctors, specialists and rheumatoid arthritis patients, confirmed that cox-2 drugs, including Vioxx, increase the risk of cardiovascular problems such as heart attacks and strokes. But in a report released yesterday it concluded those risks are similar to dangers posed by other anti-inflammatory agents, such as ibuprofen, which have been on the market for 50 years.
The panel recommends the continued sale of Celebrex, and the return of Vioxx, provided that all anti-inflammatory drugs carry explicit warnings of their heart risks.
Those risks are greatest for people who already have heart problems, the panel said, and when the drugs are taken at higher doses for longer periods of time.
Most notably, the panel calls for the over-the-counter pain reliever ibuprofen -- which is sold under names such as Motrin and Advil -- to be moved behind the counter so pharmacists can discuss with customers the risk of cardiovascular side effects before they buy it.
"There's no drug that I know of that's beneficial that doesn't have some harms as well," said panel chairman Andreas Laupacis, chief executive officer of the Institute for Clinical Evaluative Sciences in Toronto.
Cox-2 drugs were developed with great fanfare in the 1990s, heralded as compounds that could offer pain relief, particularly for arthritis sufferers, without harming the stomach, a known effect of traditional non-steroidal anti-inflammatory drugs (NSAIDS), such as ASA. But cox-2 drugs quickly became one of the biggest controversies in medicine, as reports emerged that Vioxx was linked to thousands of deaths in North America and pulled from the market last fall. The fallout led Health Canada to create the review panel.
The panel's report says that because cox-2 drugs carry heart risks similar to traditional painkillers, yet seem to have a lesser chance of causing stomach problems, patients could "benefit from having a variety of drugs to choose from for pain relief."
Still, the panel recommended that Bextra, which Pfizer voluntarily pulled from the market in April, not return after finding there was insufficient safety information about the drug.
Health Canada officials say they will immediately implement many of the panel's recommendations, but noted that federal officials do not have the power to force a non-prescription drug such as ibuprofen to be moved behind the counter.
Marc Berthiaume, Health Canada's director of the marketed pharmaceuticals, said only provincial health authorities can make that change. He said Health Canada will pass on the panel's recommendation regarding ibuprofen to the provinces, but the department has not yet decided whether it endorses that suggestion.
Dr. Berthiaume said Health Canada will also ask all manufacturers of anti-inflammatory drugs to update the safety information of their products.
He stressed, however, that Vioxx-maker Merck Frosst Canada will have to request the drug be sold again before it could return to Canadian pharmacies.
Merck Frosst spokeswoman Marlene Gauthier said that while the company "respected" the panel's recommendations, it has not yet decided whether it will reapply for the drug's return.
The panel's recommendations flow from a two-day forum Health Canada held last month, at which a range of views from drug makers, medical experts, patients and the public were presented. The overwhelming message at the forum, Dr. Laupacis said, was that patients want to be able to make informed decisions for themselves.
Based on a review, compiled by University of Oxford epidemiologist Colin Baigent, of 138 randomized trials involving 144,296 patients, the panel found that cox-2 drugs can increase high blood pressure, cause limb swelling and kidney malfunction. But the report also noted that "randomized trials have consistently shown that NSAIDS also increase the risk of hypertension and edema (swelling) compared to a placebo."
At a glance
Highlights from report of the expert advisory panel, struck by Health Canada to review the safety of cox-2 inhibitor drugs:
The panel voted unanimously to allow the continued sale of Celebrex, made by Pfizer Inc.
The panel voted 12-1 to allow Vioxx, made by Merck Frosst Canada Inc., back on the market.
The panel voted 8-5 that Bextra, which Pfizer suspended in April, not be allowed back on the market because there is not enough information about its cardiovascular safety and there are concerns about it raising the risk of a rare but serious skin disorder.
The panel found all anti-inflammatory drugs carry an increased risk of cardiovascular disease, with the possible exception of naproxen. (Naproxen is available by prescription in Canada, but is sold over the counter in the United States.)
The panel felt that no additional Vioxx trials should be ordered before its return to market, but recommended a number of studies to look in detail at the outcome of use of all anti-inflammatory drugs in the real world.
The panel also called for all trials and information that a drug company submits to Health Canada to be made publicly available. Health Minister Ujjal Dosanjh has said he is working toward that goal.