FDA Panel Frowns on Vioxx Successor

Merck is seeking the FDA's approval to sell Arcoxia, also known as etoricoxib, to treat the signs and symptoms of osteoarthritis. Merck, based in Whitehouse Station, N.J., withdrew Vioxx in 2004 after the drug was linked to a higher risk of stroke and heart attack when compared with dummy pills.

The FDA is not required to follow the recommendations of its advisory committees, but the agency usually does. Merck expects the FDA will make a final decision by April 27.

''Merck's disappointed. We continue to believe Arcoxia has the potential to become a valuable treatment option for many Americans suffering from osteoarthritis,'' company spokeswoman Kyra Lindemann said.

Panel member Dr. Richard Cannon said the decision came down to whether patients needed another nonsteroidal anti-inflammatory drug, or NSAID. There are about 20 drugs in this class and they are common treatments for osteoarthritis, which affects an estimated 21 million people in the United States.

''We don't have strong data that there is a need for this drug, compared to what's already available,'' said Cannon, a cardiologist with the National Heart, Lung and Blood Institute.

Fellow panelist Dr. James Fries, a Stanford University rheumatologist, called it a ''weak argument'' that there was a ''crying need'' for more treatment options.

Arcoxia is the first drug of its class to go before the FDA for approval since Merck withdrew Vioxx.

''We continue to believe the overall risk-to-benefit profile is favorable to support approval of Arcoxia,'' Dr. Scott Korn, executive director of regulatory affairs for Merck's research laboratories, said after the meeting.

Merck has compiled more long-term safety data for the experimental drug than for any other NSAID, said Peter Kim, president of Merck's research laboratories.

Arcoxia and Vioxx are types of NSAIDs called Cox-2 inhibitors, developed to be gentler on the stomach.

The FDA said this week that new NSAIDs that increase the risk of stroke and heart attack should not win approval if safer alternatives are available.

''The idea should not be we need new drugs. The idea should be we need better drugs,'' said Martha Solonche, the advisory panel's patient representative.

In evaluating Arcoxia and all other drugs from that class, the FDA said it would focus on the risks to the cardiovascular system.

NSAIDs deserve approval only if they fill a need for a particular group of patients for whom there are no relatively safer options, the FDA said in a memorandum released this week. The FDA does not doubt Arcoxia works for osteoarthritis.

The only Cox-2 inhibitor still sold in the United States is Pfizer Inc.'s Celebrex. The New York company withdrew another of the drugs, Bextra, in 2005.

Merck said the cardiovascular risk of Arcoxia was comparable to another older NSAID, diclofenac, based on the results of a study that enrolled nearly 35,000 patients. Arcoxia causes more high blood pressure than the older drug.

Graham, the FDA drug safety expert, and other critics believe it would have been more fair to compare other NSAIDs, such as naproxen, sold as Aleve and under other names. They contend diclofenac raises heart risks; Merck disputes that.

Diclofenac is widely used worldwide. In the U.S., however, it accounts for just 5 percent of the market for prescription NSAIDs.

Based on smaller and shorter studies, Merck said the cardiovascular risk of Arcoxia was consistent with that posed by other NSAIDs, but greater than that posed by naproxen. The company sells Arcoxia in 63 other countries.

In the U.S., the safety of Cox-2 inhibitors has drawn scrutiny from regulators, drug companies, academics, lawmakers, advocacy groups and the media in the wake of Vioxx's withdrawal.

Merck has been swamped by more than 27,000 personal injury lawsuits alleging harm from Vioxx.