A crucial test begins this week for regulators in the United States and their efforts to calm concerns over drug safety as a panel begins hearing Merck's application for the painkiller Arcoxia.
A Food and Drug Administration panel of outside experts meets on Thursday to consider whether to approve Arcoxia, whose application has been on hold for nearly three years. The painkiller, in a class called cox-2 inhibitors, is the heir to Vioxx, a drug which Merck withdrew from the market in September 2004 after finding that it had increased the risk of heart attacks and strokes.
The withdrawal of Vioxx - a global blockbuster with $2.5 billion in annual sales - ignited controversy among regulators, government, doctors and large pharmaceutical companies.
It prompted recriminations and re-examination of US drug safety regulations and drug marketing and pushed all cox-2 drugs but one - Celebrex, made by Pfizer - off the market.
Merck faces almost 30,000 lawsuits over Vioxx.
Arcoxia has been delayed since then while the FDA sought more long-term data on its safety and efficacy. The backbone of Merck's presentation for approval is a four-year clinical trial programme, called Medal, which researched Arcoxia in 34,000 people over three studies.
Medal showed that users of Arcoxia had similarly low rates of heart attacks and strokes compared with users of diclofenac, an arthritis drug widely used around the world but not in the US.
But the drug had significantly higher rates of heart-related side-effects, such as high blood pressure and fluid retention.
These findings have not dispelled the spectre of Vioxx. Some in the medical profession claim that Arcoxia has not been shown to be safe enough to be approved and say that diclofenac is the wrong drug to use in comparison.
Dr Steven Nissen, a cardiologist at the Cleveland Clinic and a cox-2 expert, has repeatedly said that Arcoxia should not be approved: "This is a genie I don't want to see let out of the bottle."
This public scepticism once again makes the FDA's review of a cox-2 drug a proxy for its safety policies and systems.
Since the withdrawal of Vioxx the FDA has been under heavy bipartisan scrutiny from Congress. Legislators have introduced bills to overhaul the FDA and its drug safety processes, while the agency has attempted to improve communication and responsive safety vigilance.
The FDA has acknowledged that Arcoxia is sensitive, thereby warranting the advisory committee hearing. It said that new cox-2 drugs could be approved, but only if the data was similar to other drugs in its class.
Merck is so confident of Arcoxia that it has included projected US sales in its profit forecast for this year. - ( Financial Times Service)
