Adalimumab, an injectable anti-TNF therapy that has FDA approval for treating rheumatoid arthritis in adults, has proven effective in children with juvenile rheumatoid arthritis, according to research presented this week at the American College of Rheumatology Annual Scientific Meeting in Washington, DC.
The immunosuppressant adalimumab, currently used to treat adults with moderate to severe rheumatoid arthritis, targets inflammation by blocking TNF (tumor necrosis factor) proteins in the body. Following studies that demonstrated safety and effectiveness in adults with rheumatoid arthritis, this study in children with juvenile rheumatoid arthritis was performed. Juvenile rheumatoid arthritis affects an estimated 285,000 children in the U.S. The disease, which starts before they reach age 16, can cause joint stiffness, reluctance or refusal to use arms or legs, reduced activity levels, persistent pain and joint swelling. If not effectively treated, it can result in joint damage, growth delay and decreased bone mineralization.
To assess the long-term effectiveness and safety of adalimumab in a younger population, researchers conducted a 48-week randomized study on 171 children, ages 4 to 17, with five or more swollen joints and three or more joints with limited range of motion at the outset of the study. The subjects were categorized as those taking and not taking methotrexate at the beginning of the study. The dose of methotrexate and all other arthritis medications remained stable throughout the trial. Adalimumab doses were based on the child's size, with participants receiving 24 mg/M2 BSA, maximum of 40 mg, given as a subcutaneous injection every 2 weeks over a 16-week period. At the end of the 16 weeks, the 83% (142) of the subjects who met the definition of "responder" for this study were randomized into a double-blind study and assigned to either continue adalimumab or switch to a placebo for the next 32 weeks or until disease flare-up.
Results demonstrated that participants receiving adalimumab had significantly fewer disease flares than those on placebo. Of those not already taking methotrexate, 43% randomized to adalimumab and 71% to placebo flared; of those already on methotrexate, 37% and 65%, respectively flared. The most common problems were mild upper respiratory infections. No tuberculosis or opportunistic infections were reported.
"Based on this data, adalimumab taken with or without methotrexate provided rapid, substantial and sustainable improvement for children with very active juvenile rheumatoid arthritis," explains Daniel J. Lovell, MD, MPH, Chairman, Pediatric Rheumatology Collaborative Study Group, Cincinnati, Ohio and an investigator in the study. "Given that the medication was generally well tolerated, adalimumab has emerged as an excellent treatment option for children with juvenile rheumatoid arthritis."