The FDA's Arthritis Advisory Committee voted 20-1 against recommending approval of Merck's Arcoxia, a potential successor to Vioxx as a treatment for arthritis pain.

The committee's opposition to the drug was due mainly to concern over cardiovascular risks and lack of proof that it offers a significant benefit over other, similar drugs.

Studies of Arcoxia (etoricoxib) show the drug may increase the risk of high blood pressure and congestive heart failure, but is as effective as diclofenac in treating arthritis pain, the FDA said. The drug has been approved for sale in more than 60 countries.

The committee's overall concern about the cardiovascular safety of Arcoxia potentially extends to "the entire class" of Cox-2 inhibitors and even to all nonsteroidal anti-inflammatory drugs, "with the possible exception of naproxen," Robert Meyer, director of the FDA's Office of Drug Evaluation II, said in a conference call announcing the vote.

While not required to, the FDA typically follows committee recommendations.