Associate Professor Sean O'Neill serves in the Northern Clinical School, Faculty of Medicine and Health at the University of Sydney, holding the position of Associate Professor in Rheumatology. He earned a Bachelor of Medicine (BMed), a PhD through research conducted in London and at Royal North Shore Hospital, and Fellowship of the Royal Australasian College of Physicians (FRACP). His career trajectory includes an earlier role as Research Fellow in the Department of Rheumatology and Back Pain Research Group at Royal North Shore Hospital, University of Sydney. Currently, he is affiliated with the Institute of Bone and Joint Research at the Kolling Institute of Medical Research and contributes to Sydney Musculoskeletal Health as a researcher in the clinical research, health services, and population health theme, as well as a member of its advisory group. O'Neill practices as a consultant rheumatologist at Liverpool Hospital, Royal North Shore Hospital, and Concord Repatriation General Hospital.

O'Neill's academic interests center on rheumatology, with extensive research on systemic lupus erythematosus (SLE), including risk of flare and damage accrual after tapering glucocorticoids, prevalence, determinants, and outcomes of low disease activity states, predictors of damage accrual by organ domain, sex differences, telehealth-supervised exercise interventions, and treatment patterns with treat-to-target goals. His work also addresses rheumatoid arthritis, such as cardiovascular disease risks, low back pain through social media content analysis, and endothelial protein C receptor impacts on rheumatic diseases. He has authored or co-authored 121 publications, accumulating over 2,357 citations. Notable contributions include the article 'Risk of flare and damage accrual after tapering glucocorticoids in systemic lupus erythematosus: an international post-hoc analysis from the Asia-Pacific Lupus Collaboration cohort' (Annals of the Rheumatic Diseases, 2024), 'Prevalence, Determinants, and Outcomes of Low Disease Activity States in Systemic Lupus Erythematosus: An International Inception Cohort Study' (Arthritis Care & Research, 2025), 'Predictors of damage accrual by organ domain in systemic lupus erythematosus: an international cohort study' (Rheumatology, 2025), 'Telehealth-supervised exercise in systemic lupus erythematosus: a randomised controlled trial' (Lupus, 2023), and editorship of 'The Musculoskeletal System - Edition 3' (Elsevier, 2022). He co-authored the position statement on low-dose methotrexate use for Australian rheumatology practice (2020).

Professional Email: sean.oneill@sydney.edu.au