IL-23/Th17 targeted therapies in SAPHO syndrome. A case series.

SAPHO syndrome is a rare entity with skin and rheumatologic inflammatory presentation. The treatment is not standardized, and in case of inadequate response to anti-inflammatory drugs, the use of anti-TNF or anti-IL-1 biologic treatments has been reported. The IL-23/Th17 axis may be involved in SAPHO syndrome. We report the results of six courses of IL-23 and IL-17 targeted therapies (3 ustekinumab and 3 secukinumab) in patients with SAPHO syndrome unresponsive to previous treatments (csDMARDs and bDMARDs). With a mean treatment duration of 5.5 months, improvement of skin symptoms was noticed in three cases, one improvement with secukinumab and two remissions (one with secukinumab, one with ustekinumab). Regarding the rheumatic symptoms, no major improvement was obvious under any of the six treatment courses. No particular safety concerns were reported, except cases of paradoxical psoriasis flare in one under ustekinumab and the other case under secukinumab.