JAK Inhibitors for Treatment of SAPHO Syndrome: A Systematic Review of 72 Cases

Abstract

Objective Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome usually involves bones, joints, and skin. Due to a lack of known pathogenesis and clinical trials, there is no standard treatment of SAPHO syndrome. Because none of the current treatments have a high efficacy and the risk of relapse is high, new treatment options for SAPHO syndrome are necessary. JAK inhibitors (JAK-I) are a group of small-molecule drugs with a wide range of effects on inflammatory and autoimmune pathways. Methods A systematic search was conducted using medical subject headings terms or keywords related to JAK-I and SAPHO syndrome through PubMed/Medline, Scopus, Web of Science, and Embase until September 8, 2024. The inclusion criteria included a patient diagnosed with SAPHO syndrome who received at least one JAK-I. We excluded reviews and animal studies. Results Of 287 initially researched articles, we included 34 articles. These 34 articles represent 72 patients with a mean age of 39.36 years. Of these, 56 (78) were female. All patients had bone or joint involvement, and 64 patients had skin involvement. Seventy patients (97.2) had received at least one treatment before using JAK-I. All patients received just one JAK-I. Of these, 54 (75) received tofacitinib, 15 (20.8) received baricitinib, and 3 (4.2) received upadacitinib. All patients except one (98.6) showed good to complete response. Ten patients (13.9) showed a clinical adverse effect. All were taking tofacitinib, with adverse effects leading to drug discontinuation in just one of these patients. Conclusion JAK-I seems to be a promising treatment of SAPHO syndrome, with manageable adverse effects.