Vioxx (rofecoxib), Merck & Co. Inc.'s once-daily arthritis and pain medicine, has been approved by the US FDA for the relief of the signs and symptoms of the most common forms of JRA (pauciarticular or polyarticular) in children two years and older and who weigh at least 22 pounds.

Vioxx is now the first and only COX-2 specific inhibitor approved for the treatment of JRA, based on clinical research that established safety and effectiveness in children as young as 2 years of age and who weigh at least 22 pounds, Merck said in a release.

The FDA approval of Vioxx for JRA was based on the JRA study, which included 310 paediatric and adolescent patients aged 2 to 17 with active pauciarticular or polyarticular JRA. Results from the pivotal 12-week multi-national, double-blind study showed once-daily Vioxx provided measurable improvement in reducing joint symptoms. Improvement was evaluated based on JRA DOI 30 criterion, a core set of standardized criteria to measure arthritis impact. A one-year open-label extension to the pivotal study also was conducted to evaluate the long-term safety of Vioxx.

Clinical investigator Elizabeth Candell Chalom, director of Paediatric Rheumatology, Saint Barnabas Paediatric Subspecialty Centre in Livingston, said, "With the approval of Vioxx for JRA, we now have a new treatment option that has been shown to be effective in relieving joint symptoms. It offers the convenience of once-daily dosing and is available in a tablet and a strawberry-flavoured liquid formulation."

The approval of Vioxx for the relief of the signs and symptoms of JRA follows the recent approval of Vioxx in March for the acute treatment of migraine in adults. Vioxx now has more approved indications than any other COX-2 specific inhibitor. The new indication for JRA further expands the eligible patient population for Vioxx; in addition to the newer indications to treat JRA and migraine pain, Vioxx also is approved for the relief of the signs and symptoms of osteoarthritis and rheumatoid arthritis in adults, management of acute pain in adults and the treatment of primary dysmenorrhea. Since the introduction of Vioxx, over 100 million prescriptions have been written in the United States, the release added.

Juvenile rheumatoid arthritis, the most common form of arthritis in children, can occur in children of any age, but girls are more likely to be affected than boys. In March, Merck was granted orphan drug designation for Vioxx for the treatment of JRA, which is known to cause persistent joint inflammation and stiffness that can affect any joint in the body.