Background Infliximab (a human murine chimeric anti-tumour necrosis factor alpha monoclonal antibody) is known to decrease disease activity of juvenile idiopathic arthritis (JIA) but its effect on longitudinal growth in relation to puberty is not clear.
Objectives To assess efficacy of infliximab in patients with different forms of active JIA. To assess the dynamics of longitudinal growth in prepubertal and pubertal patient’s with JIA in response to infliximab.
Methods An open-label, non-randomised, observational study of infliximab efficacy in 25 children with juvenile idiopathic arthritis (JIA). 15 of all children (60%) had systemic JIA and 10 of all - (40%) had polyarticulare. All children had high degree (III) of disease activity.To assess the dynamics of longitudinal growthwas conducted in 13 children,8 of the prepubertal and 5 - the puberty. 9 of all 13 children (69,2%) had systemic JIA, 2 of all 13 children (15,4%) – poliarticular JIA, other 2 of 13 children (15,4%) – JIA, enthesitis - related arthritis. The study was subjected to information about forms and variants of JIA, sex, age, diagnosis, and therapy. Treatment efficacy was assessed according to the American College of Rheumatology (ACR) criteria for pediatric patients: ACR Pediatric 30 (Pedi 30), Pedi 50, Pedi 70. Growth was estimated by measuring and comparing patient’s height standard deviation score(SDS) in relation to the midparental height, the change of this value (ΔhSDS) from -1 to 0 and 0 to 1 year of treatment and the change between the ΔhSDS values to assess growth improvement. Treatment efficacy was assessed according to criteria ACR pedi. Infliximab was administered in connection with ineffectiveness of standard antirheumatic therapy (methotrexate, leflunamide, cyclosporine A, methotrexate + cyclosporine A combination).
Results In systemic JIA group at 12 mo endpoint 11 (73%) patients have demonstrated response in ACR Pedi 30; 8 (53,5%) – in ACR Pedi 50, and 6 (40%) – in ACR Pedi 70, and 2 (13,3%) patients have had low efficacy of infliximab therapy.In poliarticular JIA group at 12 mo endpoint all patients (100%) have demonstrated response in ACR Pedi 30; 8 (80%) – in ACR Pedi 50 and 5 (50%) – in ACR Pedi 70. In the prepubertal group the relation height SDS (mean ± standart error of the mean) was -1.53±1,-2.07±1 and 1.45±1.61 at -1, 0 and 1 year of infliximab treatment respectively. The ΔhSDS before infliximab was -0.54±0.27, over the first year with infliximab ΔhSDS was 0.62±0.9(p>0,05). In the pubertal group the SDS was-1, 39±2.36, -3.12±2.6, and -3.12±2.61 at -1, 0 and 1 year of treatment respectively. The ΔhSDS before infliximab was -0.73±0.43, over the first year with infliximab ΔhSDS was -0.004±0.47 (p>0,05). Individual analysis of each patient revealed that most children of the pubertal group (3/5) and the prepubertal group (6/8) showed improvement in longitudinal growth during treatment with infliximab.
Conclusions Infliximabtherapy is proven to be effective for the majority of patients with long standing history of the disease, high disease activity, and no/low efficacy of disease modifying anti-rheumatic drugs.Infliximab treatment in addition to a significant therapeutic effect also showed an increase of longitudinal growth in children suffering from idiopathic rheumatoid arthritis.
Disclosure of Interest None Declared