Around 40% of systemic juvenile idiopathic arthritis (SJIA) in Thailand is steroid dependent or fails to respond to conventional therapy; therefore, tocilizumab (TCZ), a humanized anti-IL-6 receptor antibody, was indicated in these patients. Due to financial problems, some patients cannot receive TCZ treatment immediately following failure of the conventional treatment occurs, leading to disability and poor quality of life. Therefore, this study focused on the outcomes between early and late TCZ treatment in SJIA patients. This was an observational study. Baseline characteristics and disease severity were collected. Patients were divided into the early TCZ treatment group and the late TCZ treatment group. The outcomes of this study were the remission rates by the end of the study and treatment response using the American College of Rheumatology Pediatric (ACR Pedi) 30, 50, 70 criteria at 3, 6, 9, and 12 months after TCZ initiation. Descriptive analyses were conducted to determine the outcomes. Twenty-three SJIA patients were included in this study. At the end of this study, patients in the early TCZ treatment had a remission rate of 54.5%, whereas none in the late TCZ treatment achieved remission. At the 12-month follow-up, 10 patients (91%) in the early TCZ treatment group and 6 patients (50%) in the late TCZ achieved ACR Pedi 70. The outcomes of TCZ treatment in SJIA patients depend on the time to start TCZ treatment. In the early TCZ treatment, SJIA patients had a higher remission rate and better treatment response than patients who received TCZ treatment late.
Keywords: Disease outcome; Remission rate; Systemic juvenile idiopathic arthritis; Tocilizumab; Treatment response.