Symptom assessment in hypereosinophilic syndrome: Toward development of a patient-reported outcomes tool

A patient-reported outcomes (PROs) instrument measuring symptoms of HES would provide valuable information for use in clinical practice as well as inform end-point selection and assessment of treatment effects in clinical trials.3,4 Although PROs have been developed in a wide variety of disorders, including both organ-restricted eosinophilic disorders5 and disorders with heterogeneous, multisystem involvement, such as systemic lupus erythematosus,6 no PRO questionnaires developed specifically to measure the symptoms, disease impacts, or health-related quality of life of patients with HES have been created because of the rarity of HES, the heterogeneity of clinical presentations, and confounding by the wide array of medications used to treat HES.1,2,7 Understanding the patient experience of disease is essential to support qualitative research and the development of PROs specific to HES. [...]the main objective of the current study was to understand the symptoms of patients with HES, and disease experience for end-point selection and PRO development for use in clinical care and clinical trials of novel therapies in accordance with the Food and Drug Administration PRO guidance.3,4 Literature review and concept elicitation interviews of 26 patients with HES (see Figure E1 and Table E1-E3 in this article's Online Repository at www.jaci-inpractice.org) were used to understand important symptom concepts and impacts on health-related quality of life. Patients recruited from an institutional review board–approved study for evaluation of patients with eosinophilic disease had standard assessments and were interviewed (for assessments, demographic characteristics, and interview methods, see this article's Online Repository at www.jaci-inpractice.org). Information from the literature review (Table E2), 3 clinical studies of mepolizumab in HES (NCT00086658; NCT00097370; NCT00244686; Table E2), and expert feedback (including from authors P.K. and A.K.) was used to create a draft conceptual model of key concepts related to HES disease activity (Figure E2).Patient selection Patients were recruited from an institutional review board–approved study of eosinophilia (NCT00001406).