Giant Cell Arteritis Refractory to Interleukin-6 and Interleukin-17 Inhibition Treated With Upadacitinib.

Giant cell arteritis (GCA) is a granulomatous vasculitis that can involve both cranial and extracranial vessels. Although interleukin-6 (IL-6) receptor blockade is an established therapy, treatment options for medically refractory disease remain limited. We report a unique case of extracranial GCA refractory to glucocorticoids, azathioprine, tocilizumab (IL-6 inhibitor), and secukinumab (IL-17A inhibitor) that responded robustly to upadacitinib, a selective JAK1 inhibitor. To our knowledge, this is the first reported case of GCA demonstrating resistance to both IL-6 and IL-17 inhibition but clinical and imaging remission with JAK inhibition, highlighting the role of upadacitinib as a therapy for patients with GCA.