Merck & Co Inc. has announced that the US Food and Drug Administration (FDA) issued a non-approvable letter in response to the company's New Drug Application (NDA) for Arcoxia (etoricoxib) for the symptomatic treatment of osteoarthritis (OA).

Arcoxia has been under review by the FDA as an investigational selective COX-2 inhibitor since the NDA was submitted in December 2003 for a 60 mg once-daily dose along with review of a separate related NDA for a 30 mg once-daily dose submitted in April 2004.

In the non-approvable letter, the FDA indicated that Merck would need to provide additional data in support of the benefit-to-risk profile for the proposed doses of Arcoxia in order to gain approval.

"We are disappointed with today's decision," said, Peter S Kim, PhD, president, Merck Research Laboratories. "We pursued FDA approval of Arcoxia because we believe strongly that new medicines are needed for patients whose osteoarthritis pain is inadequately managed with currently available therapies. In addition, there is more long-term safety data from controlled clinical trials, in terms of patient-years on treatment, for Arcoxia than for any other NSAID, including traditional NSAIDs and Cox-2 selective inhibitors."

Arcoxia is available in 63 countries in Europe, Latin America, the Asia-Pacific region and Middle East/Northern Africa. Merck will continue to market Arcoxia outside the United States, where it has been approved for a broad range of indications, including OA.