Abstract: Objective: To evaluate the safety and efficacy of upadacitinib in patients with SAPHO syndrome. Methods: The clinical data of five patients with SAPHO syndrome treated effectively with upadacitinib from January 2021 to June 2023 were retrospectively analyzed. Results: All five patients reported in this paper suffered from palmoplantar pustulosis with arthritic involvement with two presenting with nail loss. All had previously been ineffectively treated with NSAIDs, DMARDs, bisphosphonates, biologics or baricitinib. After switching to treatment with upadacitinib, patients experienced relief of skin lesions and bone pain, and no data of adverse events were found. Conclusions: Upatinib may be an option for the treatment of SAPHO syndrome, especially in cases where treatment with multiple biologics has failed.

Key words: SAPHO syndrome, upadacitinib, JAK inhibitor, palmoplantar pustulosis