Tocilizumab in VEXAS relapsing polychondritis: a single-center pilot study in Japan.

Recently, a rare severe autoinflammatory disease vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic (VEXAS) syndrome caused by somatic variants in the UBA1 gene was discovered.1 We reported the clinical features of eight relapsing polychondritis (RP) patients with UBA1 variants, six of which were accompanied by myelodysplastic syndrome (MDS).2 The clinical features of VEXAS syndrome are heterogeneous, including high-grade fever, polychondritis, large vessel vasculitis, skin eruptions, arthritis, thrombosis, scleritis and serositis, which require intensive immunosuppressive agents. Most of our patients before this study had received high doses of prednisolone (PSL) and cytotoxic immunosuppressants including methotrexate, cyclophosphamide and azathioprine.1 2 However, even with concomitant immunosuppressant treatment, PSL tapering often led to a relapse of high-grade fever and skin rash in these patients; therefore, ≥20 mg oral PSL was required in most cases, resulting in frequent hospitalisation and death due to opportunistic infections. In addition, many cases of VEXAS syndrome already have MDS at the time of diagnosis, and cytotoxic immunosuppressive agents should be avoided or reduced in dose because they might cause further cytopenia. Tocilizumab (TCZ), an anti-interleukin (IL)-6 receptor antagonist approved for the treatment of inflammatory diseases, such as rheumatoid arthritis and giant cell arteritis, may be useful in managing severe inflammation in VEXAS–RP and preserving the cumulative dose of PSL, which …