Therapeutic efficacy of humanized recombinant anti–interleukin-6 receptor antibody in children with systemic-onset juvenile idiopathic arthritis
Article first published online: 4 MAR 2005
Copyright © 2005 by the American College of Rheumatology
Arthritis & Rheumatism
Volume 52, Issue 3, pages 818–825, March 2005
How to Cite
Yokota, S., Miyamae, T., Imagawa, T., Iwata, N., Katakura, S., Mori, M., Woo, P., Nishimoto, N., Yoshizaki, K. and Kishimoto, T. (2005), Therapeutic efficacy of humanized recombinant anti–interleukin-6 receptor antibody in children with systemic-onset juvenile idiopathic arthritis. Arthritis & Rheumatism, 52: 818–825. doi: 10.1002/art.20944
- Issue published online: 4 MAR 2005
- Article first published online: 4 MAR 2005
- Manuscript Accepted: 2 DEC 2004
- Manuscript Received: 19 MAR 2004
To investigate the safety and efficacy of a recombinant human anti–interleukin-6 (anti–IL-6) receptor monoclonal antibody (MRA) that indirectly inhibits the effects of IL-6 in children with systemic-onset juvenile idiopathic arthritis (JIA) refractory to high-dose, long-term corticosteroids.
An individual escalating-dose trial was conducted in 11 children with active systemic-onset JIA who met the inclusion criteria. All were first administered an intravenous dose of 2 mg/kg MRA. Each child without active inflammation was given a second identical dose 2 weeks later and a third identical dose 2 weeks after the second dose. Children with disease flares according to laboratory marker values received a 4-mg/kg dose. Those without disease flares at this dose received a second 4-mg/kg dose 2 weeks later and a third 4-mg/kg dose 2 weeks after the second dose, while those with active inflammation received an additional 3 doses of 8 mg/kg MRA. Efficacy was evaluated every 2 weeks according to responses on the JIA core set of improvement criteria and the results of laboratory tests.
MRA abruptly reduced disease activity in 10 of the 11 children, as assessed by the occurrence of febrile episodes, active arthritis, scores on the Childhood Health Assessment Questionnaire, and levels of acute-phase reactants. However, levels of inflammatory reactants fluctuated until the proper MRA dose for each child was reached. Two weeks after the third fixed dose of MRA, 90.9% of all patients had a 30% improvement response, 90.9% had a 50% improvement response, and 63.6% had a 70% improvement response.
MRA treatment of children with active systemic disease results in clinical improvement and in normalized levels of acute-phase reactants. MRA was safe and well tolerated and provided greater clinical benefit than conventional corticosteroids, considering the ill effects of IL-6 and adverse events.