Reasons for Initiating Canakinumab among Patients with Systemic Juvenile Idiopathic Arthritis and Adult-Onset Still’s Disease in the U.S. Real-World Settings

INTRODUCTION: The aim of this study was to understand the reasons for canakinumab initiation among patients with Still’s disease, including systemic juvenile idiopathic arthritis (SJIA) and adult-onset Still’s disease (AOSD), in US clinical practice. METHODS: Physicians retrospectively reviewed the medical charts of patients with Still’s disease (regardless of age at symptom onset) who were prescribed canakinumab from 2016 to 2018. Patients aged < 16 years at symptom onset were classified as having SJIA and those aged ≥ 16 years at symptom onset (calculated from case-record forms) were classified as having AOSD. Patient treatment history and physician reasons for canakinumab initiation were analyzed. Overall results were presented as SJIA/AOSD. Sensitivity analyses were performed for the robustness of the results. RESULTS: Forty-three physicians in the USA (rheumatologists/dermatologists/immunologists/allergists: 51.2/27.9/11.6/9.3%; subspecialty in adults/pediatrics: 67.4/32.6%) abstracted information for 72 patients with SJIA/AOSD (SJIA/AOSD/age unknown at symptom onset: 75.0/18.1/6.9%; mean age 19.4 years; children 61.1%; females 56.9%). Most patients (90.3%) received treatment directly preceding canakinumab initiation (etanercept 27.7%; anakinra 18.5%; adalimumab 16.9%); the respective treatment was discontinued due to lack of efficacy/effectiveness (43.1%) and availability of a new treatment (27.8%). Most common reasons for canakinumab initiation were physician perceived/experienced efficacy/effectiveness of canakinumab (77.8%; children/adults: 81.8/71.4%), lack-of-response to previous treatment (45.8%; children/adults: 36.4/60.7%), convenient administration/dosing (26.4%; children/adults: 29.5/21.4%) and ability to discontinue/spare steroids (25.0%; children/adults: 20.5/32.1%). The sensitivity analysis provided similar results. CONCLUSIONS: In US clinical practice, physician perceived/experienced efficacy/effectiveness of canakinumab and lack-of-response to previous treatment were the primary reasons for canakinumab initiation among patients with SJIA/AOSD. Physician perceived/experienced efficacy/effectiveness and convenient administration/dosing of canakinumab were the most common reasons for canakinumab initiation among children, whereas lack-of-response to previous treatment and ability to discontinue/spare steroids being the most frequent reasons among adults. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40744-021-00402-z.