Haematopoietic stem cell transplantation (HSCT) was an effective and definitive treatment in 14 patients with deficiency of adenosine deaminase 2 (DADA2), a monogenic autoinflammatory vasculopathy. All patients reported resolution of immunological and haematological phenotype, with no new vascular events at an average of 18 months follow-up, and adenosine deaminase 2 activity normalized as early as 14 days post-HSCT in those patients tested (n = 7). Adverse events were reported in 11 of the 14 patients (four incidents of cytopenia and seven incidents of moderate or acute graft-versus-host disease).