Long-term efficacy and safety of subcutaneous tocilizumab in clinical trials of polyarticular or systemic juvenile idiopathic arthritis.

OBJECTIVE: To investigate the safety and efficacy of subcutaneous tocilizumab (SC-TCZ) treatment in a long-term extension (LTE) of clinical trials in polyarticular or systemic juvenile idiopathic arthritis (pJIA, sJIA). METHODS: Patients with pJIA or sJIA from two open-label, 52-week phase 1 b core trials of SC-TCZ who had adequate response per investigator assessment entered the LTE and continued SC-TCZ treatment according to body weight-based dosing regimens until commercial availability or up to 5 years. Pharmacokinetics, pharmacodynamics, and efficacy were assessed for up to 3 years and safety for up to 5 years in the LTE. RESULTS: Forty-four patients with pJIA and 38 patients with sJIA entered the LTE. Tocilizumab trough concentrations were maintained within the range expected to provide clinical benefit (mean values: pJIA, ∼10 µg/ml; sJIA, ∼75 µg/ml over 3 years). Pharmacodynamic parameters (interleukin-6, soluble interleukin-6 receptor, erythrocyte sedimentation rate, C-reactive protein) were maintained throughout the LTE at levels achieved in the core trials. Inactive disease per American College of Rheumatology provisional criteria was reported for 90% (17/19) and 53% (8/15) of patients with pJIA and 91% (10/11) and 92% (12/13) of patients with sJIA in the <30 kg and ≥30 kg body weight groups, respectively. Serious adverse events in the LTE were reported in six patients with pJIA (13.6%; five serious infections) and five patients with sJIA (13.2%; one serious infection). CONCLUSION: Patients with pJIA or sJIA experienced long-term disease control with SC-TCZ treatment. Long-term safety was consistent with the known tocilizumab safety profile.

Overlap of International League of Associations for Rheumatology and Preliminary Pediatric Rheumatology International Trials Organization Classification Criteria for Nonsystemic Juvenile Idiopathic Arthritis in an Established UK Multicentre Inception Cohort.

OBJECTIVE: The goal was to assess the degree of overlap between existing International League of Associations for Rheumatology (ILAR) and preliminary Paediatric Rheumatology International Trials Organisation (PRINTO) classification criteria for juvenile idiopathic arthritis (JIA). METHODS: Participants from the Childhood Arthritis Prospective Study, a multicenter UK JIA inception cohort, were classified using the PRINTO and ILAR classification criteria into distinct categories. Systemic JIA was excluded because several classification items were not collected in this cohort. Adaptations to PRINTO criteria were required to apply to a UK health care setting, including limiting the number of blood biomarker tests required. The overlap between categories under the two systems was determined, and any differences in characteristics between groups were described. RESULTS: A total of 1,223 children and young people with a physician's diagnosis of JIA were included. Using PRINTO criteria, the majority of the patients had "other JIA" (69.5%). There was a high degree of overlap (91%) between the PRINTO enthesitis/spondylitis- and ILAR enthesitis-related JIA categories. The PRINTO rheumatoid factor (RF)-positive category was composed of 48% ILAR RF-positive polyarthritis and 52% undifferentiated JIA. The early-onset antinuclear antibodies-positive PRINTO category was largely composed of ILAR oligoarthritis (50%), RF-negative polyarthritis (24%), and undifferentiated JIA (23%). A few patients were unclassified under PRINTO (n = 3) and would previously have been classified as enthesitis-related JIA (n = 1) and undifferentiated JIA (n = 2) under ILAR. CONCLUSION: Under the preliminary PRINTO classification criteria for childhood arthritis, most children are not yet classified into a named category. These data can help support further delineation of the PRINTO criteria to ensure homogenous groups of children can be identified.