Adalimumab versus adalimumab and methotrexate for the treatment of juvenile idiopathic arthritis: long-term data from the German BIKER registry.

OBJECTIVE

Adalimumab (ADA) has become a valuable treatment option for juvenile idiopathic arthritis (JIA). The importance of combination with methotrexate (MTX) is unclear.

METHOD: Data from the German Biologics in Paediatric Rheumatology (BIKER) registry are reported. Response to treatment was analysed using JIA American College of Rheumatology (ACR) scores, 10-joint Juvenile Arthritis Disease Activity Score (JADAS10), and improvement of functional status and ACR inactive disease criteria. Compa-risons between rates of adverse events (AEs) and serious adverse events (SAEs) provided data for the safety assessment.

RESULTS

Overall, 584 patients with non-systemic JIA started ADA therapy, 61% of whom received concomitant MTX treatment at baseline. The latter patients were younger (p < 0.001), with shorter disease duration (p = 0.001), more frequently had antinuclear antibodies (p = 0.04), and had higher baseline JADAS10 scores (p = 0.03). In patients with ADA monotherapy, enthesitis-related arthritis (p = 0.004) and presence of human leucocyte antigen-B27 (p = 0.008) were documented more often. Mean treatment duration in both cohorts was 15 months. Comparable last follow-up rates for JIA ACR 30/50/70/90% response, JADAS minimal disease activity, JADAS remission, and ACR inactive disease were, respectively, 75/72/64/49%, 66%, 46%, and 58% for ADA monotherapy, and 77/72/61/45%, 64%, 48%, and 55%, for ADA + MTX. During 1082 patient-years (PY) of ADA exposure, 725 AEs (67/100 PY), including 57 SAEs (5.3/100 PY), were reported. Serious infections were reported in 10 patients (0.9/100 PY) and 11 (1.0/100 PY) had varicella infections/zoster reactivation. Rates of AEs, SAEs, infectious events, and serious infections did not differ between the cohorts. Elevated transaminases (p = 0.005) and gastrointestinal events (p < 0.0001) were reported more often in the combination cohort. Two pregnancies and no deaths were reported.

CONCLUSION

ADA demonstrated an acceptable risk profile and high percentages of patients in both cohorts showed sufficient treatment response. No differences in treatment response or adherence to treatment were found.