Intravenous Golimumab in Children With Polyarticular-Course Juvenile Idiopathic Arthritis: Long-Term Extension of an Open-Label Phase III Study

OBJECTIVE: To report pharmacokinetics (PK), immunogenicity, clinical effect, and safety of intravenous (IV) golimumab in children with active polyarticular-course juvenile idiopathic arthritis (pcJIA) who participated in A Study to Evaluate the Pharmacokinetics, Efficacy and Safety of Intravenous Golimumab in Pediatric Participants With Active Polyarticular Course Juvenile Idiopathic Arthritis Despite Methotrexate Therapy (GO-VIVA)'s open-label, long-term extension (LTE) through week 252. METHODS: GO-VIVA participants who continued IV golimumab (80 mg/m2 every 8 weeks) after week 52 were included. PK and safety were assessed through week 244 (last dose) and week 252, respectively, and clinical response through week 116. Clinical outcomes included JIA-American College of Rheumatology (ACR) responses and clinical Juvenile Arthritis Disease Activity Score in 10 joints (cJADAS10). Binary outcomes used nonresponder imputation, and other descriptive analyses used observed data. RESULTS: Of 112/127 (88.2%) participants entering the LTE, 69 completed the week 252 visit. Median steady-state trough golimumab concentrations were generally maintained from week 52 through week 244 (range 0.3-0.6 μg/mL). Antigolimumab antibody rates were consistent through week 52 (39.2% [49/125]) and week 244 (44.8% [56/125]). Week 52 JIA-ACR 30/50/70/90 response rates (75.6% [96/127], 74% [94/127], 65.4% [83/127], and 48.8% [62/127], respectively) were generally maintained through week 116 (72.4% [92/127], 71.7% [91/127], 63.8% [81/127], and 50.4% [64/127], respectively), when the median cJADAS10 was 1.6 and 56.7% (72/127) of participants achieved cJADAS10 ≤ 5 (minimal disease activity). Rates (per 100 patient-years) of serious adverse events and serious infections through week 252 were 7.7 and 3.9, respectively. CONCLUSION: GO-VIVA LTE participants experienced adequate PK exposure and stable safety and immunogenicity. The majority of participants experienced no more than minimal residual disease activity. Data suggest IV golimumab treatment provided durable clinical response through week 116, with an acceptable risk-benefit profile.