Interleukin-1 blockade in patients with Wiskott-Aldrich Syndrome: a retrospective multinational case series.

Up to 70% of patients with Wiskott-Aldrich Syndrome (WAS) develop autoimmune and inflammatory manifestations. Dysregulation of interleukin (IL)-1 may be involved in their pathogenesis, yet there is little evidence on treatment with anti-IL-1 agents in these patients. We conducted a multicenter retrospective analysis of nine patients with WAS treated with anti-IL-1 agents (anakinra or canakinumab). All patients had prominent inflammatory manifestations, including systemic, cutaneous, articular, and intestinal symptoms; three patients presented with a severe systemic inflammatory syndrome since the first months of life. Corticosteroid therapy was associated with partial or no response, while treatment with anakinra or canakinumab resulted in prompt, often dramatic, responses in all patients, allowing bridging to gene therapy (four patients) or hematopoietic stem cell transplantation (HSCT, five patients). Treatment was overall well tolerated. Low donor myeloid chimerism developed in four patients after HSCT and was associated with the appearance or the recurrence of inflammatory manifestations. A second HSCT was performed in two patients, achieving full-donor chimerism and resolution of inflammatory manifestation, while the other two patients were treated with prolonged therapy with anti-IL-1 agents. Our experience demonstrates that some inflammatory manifestations of WAS are dependent on IL-1 and respond very well to its pharmacologic blockade.