Merck's cox-2 inhibitor, Etoricoxib (Arcoxia), which is under review by the FDA to be approved for use in treatment of ankylosing spondylitis, has been shown to be more effective than Naproxen (Aleve, Naprosyn) for AS, a new study from the Netherlands finds.

The study, "Evaluation of the efficacy of etoricoxib in ankylosing spondylitis: results of a fifty-two-week, randomized, controlled study," found that etoricoxib, "is generally safe, well-tolerated, and efficacious for the treatment of AS." It also found that the drug was more effective than naproxen "over one year."

The pending, possible approvial of Arcoxia comes after the FDA has placed a black box warning on another cox-2, Celebrex, and after the FDA had Pfizer pull Bextra from the marketplace. Merck's application to the FDA seeks indications for the medication for the treatment of osteoarthritis, rheumatoid arthritis, chronic low back pain, gout and ankylosing spondylitis.