Adoption of new treatment options in non-systemic juvenile idiopathic arthritis (JIA) in clinical practice

BACKGROUND: The recent development of biological disease-modifying antirheumatic drugs (bDMARDs) and targeted synthetic DMARDs (tsDMARDs) have expanded the possibilities of pharmacological treatment for patients with juvenile idiopathic arthritis (JIA). The objective of this study is to evaluate trends in initial prescriptions for these targeted therapies in patients aged 0-18 years with non-systemic JIA in clinical practice. We also identified the approval dates and key regulatory changes for each medication.

METHODS: A retrospective cohort study was conducted using prescription records from the Wilhelmina Children's Hospital, the largest pediatric rheumatology center in the Netherlands, analyzing data from January 2012 to December 2023. The market introduction of targeted therapies for JIA were extracted from the European Medicines Agency (EMA) database.

RESULTS: Over an 11-year period, first prescriptions dates of 11 bDMARDs and tsDMARDs (N = 672) and 3 conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) (N = 720) were analysed among 696 patients. TNF-alpha inhibitors accounted for the largest proportion of bDMARDs and tsDMARDs, comprising 79.3%. The prescription of bDMARDs and tsDMARDs increased, from a relative proportion of 32.2% in 2012 to 62.7% in 2023, while the prescription of csDMARDs declined from 67.8% in 2012 to 34.3% in 2023. The prescription of JAK inhibitors rose from 1.6% in 2020 to 5.9% in 2023.

CONCLUSIONS: This study provides a comprehensive overview of the implementation of targeted therapies (bDMARDs and tsDMARDs) in non-systemic JIA over the past decade, showing a rise in targeted therapies alongside a decrease in csDMARD prescriptions. While TNF-alpha inhibitors remain the most commonly prescribed, there has been a significant rise in the prescription of JAK inhibitors and other new therapies. Factors such as route of administration, patient comfort, costs and treatment efficacy may influence the adoption of these DMARDs. The findings highlight the need for continued research to identify factors for successful implementation of these therapies in clinical practice.