Outcomes of Biologic Agent Switching Studied in Juvenile Idiopathic Arthritis

Switching between biologic agents is common among patients with juvenile idiopathic arthritis (JIA), with inadequate response being the most reason for the switch, according to study results published in Journal of Clinical Rheumatology.

Participants were aged 18 years and younger and were diagnosed with JIA before the age of 16 years. The diagnosis was consistent with the International League of Rheumatology Societies criteria. In addition, eligible participants received treatment with more than 1 biologic agent between January 2009 and 2022.

Researchers used electronic medical records to collect data on age, sex, and JIA subtype. Data were also collected on the presence of uveitis, the use of conventional treatments before biologic agents, first and second biologic drugs used, reasons for biologic agent switching, and laboratory findings. In addition, the researchers noted Juvenile Arthritis Disease Activity Score-10 (JADAS-10) values at the time of diagnosis, when biologic therapy was started, at month 3, and at month 6 after biologic agent switching.

A total of 128 patients (60.9% girls; median age of starting biologic therapy, 10 years) receiving biologic therapy were included in the study. Participants with the most frequent biologic agent switching had systemic JIA (40.6%), followed by those who had rheumatoid factor (RF)-negative polyarticular JIA and persistent oligoarticular JIA (15.6%), extended oligoarticular JIA and enthesitis-related JIA (9.3%), RF-positive polyarticular JIA (6.2%), and undifferentiated JIA (3.1%).

Among participants, 25% had their biologic agent switched once and 3.9% had theirs switched twice.

The most frequently used biologic agent was etanercept (59.3%). The most frequently observed biologic agent switches were from 1 antitumor necrosis factor (anti-TNF) agent to another anti-TNF agent (40.6%).

Reasons for biologics switching included unresponsiveness (68.8%), adverse effects (18.7%), drug intolerance (3.1%), and other reasons (9.3%).

Study limitations included the small sample size; the single center design; the lack of assessing patients who did not switch agents; and overall, the lack of generalizability of the results.

The study authors concluded that clinicians and researchers should be alert to the need for patients undergoing JIA treatment to change protocols. They noted, “[A total of 25%] of patients undergoing biological drug treatment may require biological agent switching.”