Background Juvenile idiopathic arthritis (JIA) is a severe disease of paediatric population leading to there disability. 524 children with JIA are monitored in Chelyabinsk region.
Approximately 15% of patients with inadequate response to methotrexate require treatment with biologics. Among them often Abatacept, an inhibitor of co-stimulation of T-lymphocytes Abatacept, which is registered for use in Russia in children from 6 years, occurs to be the drug of choice.
Objectives 21 JIA patients (age 6-17 years, mean age 13.4 years, 3 M, 18 F) were included. Disease duration: from 2 to 14 years (mean 6 years). JIA was diagnosed according to ILAR criteria. 6 f with arthritis were RF-positive, RF-negative polyarthritis was reported in 11 children, oligo-arthritis - in 3 children, systemic (without active systemic manifestations) in 1 patient. 6 children had bilateral uveitis. 16 patients had high disease activity. 14 children had III-IV stage of disease on radiographs. All patients II or III class of functional disability.
Methods All patients were administered 10 mg/kg of Abatacept intravenously according to the scheme: 0-2-4 week and then every 4 weeks. ACR Pedi criteria were used to evaluate the disease activity and treatment efficacy. Statistical evaluation was performed using STATISTICA 6.0 software. Non-parametric methods were used: descriptive statistics, (median, 25-th and 75-th percentiles). Wilcoxon's criterion was used for assessment of difference in two dependent variables.
Results All patients had high disease activity before Abatacept initiation. Mean number of joints affected by severe arthritis was 11,8 [4, 20] ([25; 75%]), joints with limited motion - 12,6 [4, 18], mean ESR (as measured by Panchenkov's method) was 22,8 [15, 28] mm/h, C-RP level - 15,2 [7, 18] g/l. Functional activity index (CHAQ) was 1,3 [0.75; 2.0], disease activity assessed by investigator (VAS) was 65 [50, 70] mm, patient/parents assessment of disease activity (VAS) - 65 [50, 80] mm. Prior to Abatacept treatment, including methotrexate (15 mg/m2) for at least 3 months failed to be effective in all children. However, we usually started Abatacept in patients with long-term disease. In two patients Abatacept was the second biological drug after TNF-inhibitors failure, others received Abatacept as the first biological drug. All parents signed informed consent prior to treatment initiation.
Treatment with Abatacept occurred to be effective in 19 patients (90%). Clinical remission (ACR pedi criteria ≥90%) was reported in 6 patients within 6-12 months of treatment. Disease activity decreased in 13 patients (ACR pedi criteria 30% in 2 pts, 50% - in 4 and 70% - in 6 pts). We observed improvement of the following signs: mean number of joints affected by severe arthritis decreased to 4,9 [0, 10, joints with limited motion to 7,7 [1, 12], and lowering of mean ESR (9,3 [3, 6] mm/h) and C-RP (5,5 [0, 6.0] g/l) counts. Functional activity index (CHAQ) decreased to 0,625 [0.125; 0,5], disease activity assessed by investigator (VAS) – to 30 [20, 30].
Conclusions Treatment of patients with JIA, including uveitis manifestation, Abatacept appeared to be very effective and safe biological treatment. 1/3 of children achieved clinical remission. Disease activity decreased in 90% of patients. Serious adverse event developed only in 1 patient.
Disclosure of Interest None declared