Disease burden among patients with Arginase 1 deficiency and their caregivers: A multinational, cross-sectional survey.

Arginase 1 deficiency (ARG1-D) is an ultrarare, metabolic disease which may cause spastic paraplegia, cognitive deficiency, seizures, and ultimately severe disability. The aim of this study was to assess disease burden in ARG1-D by performing a cross-sectional survey of patients with ARG1-D and their caregivers in four European countries (France, Portugal, Spain, and the United Kingdom). Patients were enrolled at participating clinics and data were collected using a web-based questionnaire. The findings indicate that there is a significant share of patients who experience severe cognitive and mobility impairment but also that there is a considerable variance in symptom severity among patients. Disease management was mostly in line with treatment guidelines and self-reported adherence to treatment was reported to be high among a majority although following diet restrictions was perceived as difficult. However, despite this, since a large share of patients experienced severe cognitive and mobility impairment an unmet need among this patient population is suggested. The introduction of disease-modifying therapies and early identification and diagnosis may help alleviate the disease burden associated with ARG1-D in the future.