Reasons for Initiating Canakinumab among Patients with Systemic Juvenile Idiopathic Arthritis and Adult-Onset Still's Disease in the US 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.