Biologic Switching among Non-Systemic Juvenile Idiopathic Arthritis Patients: A Cohort Study in the Childhood Arthritis and Rheumatology Research Alliance Registry

Objective: Biologic medications have significantly improved disease control and outcomes of patients with juvenile idiopathic arthritis (JIA). Current treatment recommendations suggest escalating therapy; including changing biologics if needed, when inactive or low disease activity is not attained. The patterns and reasons for switching biologics in clinical practice in North America are not well described.

Methods: We used the Childhood Arthritis and Rheumatology Research Alliance Registry and included individuals with JIA if they newly started a biologic after January 1, 2008 and had at least 12 months of subsequent observable time. Subjects with systemic JIA were excluded. We compared characteristics of switchers and non-switchers using chi-square for categorical variables and Wilcoxon rank sum testing for continuous variables and used linear regression for time analysis.

Results: 1361 eligible children with JIA in the registry started a biologic (94% tumor necrosis factor TNF inhibitors [TNFi]). Median follow-up time was 30 months, and 349 (26%) switched biologics. Among biologic switchers, ineffectiveness/disease flare was the most common reason for switch (202, 58%). The most common documented switch was from etanercept to another TNFi (221, 63%). The median time to switch to a second biologic decreased substantially from 55.2 months in 2008 to 7.2 months in 2016.

Conclusion: In a multicenter cohort of patients with JIA starting a biologic, one-quarter switched to a second biologic, and the time to switching decreased in recent years. Additional studies should evaluate the outcomes and optimal timing of switching and preferred sequence of biologic use.