RHEUMATOID ARTHRITIS: Edited by Joshua F. BakerTreatment of immune checkpoint inhibitor-induced inflammatory arthritisJeurling, Susanna; Cappelli, Laura C.Author Information Division of Rheumatology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA Correspondence to Laura C. Cappelli, Division of Rheumatology, Johns Hopkins University School of Medicine, 5501 Hopkins Bayview Circle, Suite 1B1, Baltimore, MD 21224, USA. Tel: +1 410 550 8089; e-mail: Lcappel1@jhmi.edu Current Opinion in Rheumatology: May 2020 - Volume 32 - Issue 3 - p 315-320 doi: 10.1097/BOR.0000000000000701 Buy Metrics Abstract Purpose of review This review summarizes the current evidence on treatment strategies for inflammatory arthritis because of cancer treatment with immune checkpoint inhibitors (ICI), prognosis of ICI-induced arthritis, and management of patients with preexisting inflammatory arthritis receiving ICI therapy. Recent findings Inflammatory arthritis is the most common rheumatic immune-related adverse event observed in patients receiving ICI therapy. Most patients can successfully be treated with low doses of corticosteroids or conventional synthetic disease modifying anti-rheumatic drugs (DMARDs). A small minority will develop severe symptoms requiring biologic therapy including TNF inhibitors and IL-6 receptor inhibitors. Many cases of inflammatory arthritis will resolve with cessation of ICI therapy. Some patients will develop persistent arthritis despite discontinuation. Patients with preexisting inflammatory arthritis (e.g. rheumatoid arthritis) commonly flare on ICI therapy, but can usually be managed with corticosteroids. Summary Inflammatory arthritis following ICI therapy for cancer is relatively common and the practicing rheumatologist should be able to recognize and manage it in conjunction with Oncology. The majority of patients respond to corticosteroids, but some will need treatment with conventional synthetic or biologic DMARDs. Additional studies should investigate the effects of immunosuppression on tumor response and the use of ICI therapy in patients with preexisting autoimmune disease. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.