Adenosine deaminase deficiency: current treatments and emerging therapeutics

ABSTRACTIntroduction: Adenosine deaminase (ADA) deficiency is a systemic metabolic disorder characterized by severe immune and non-immune abnormalities and is often fatal in infancy. ADA deficiency can be treated by allogeneic hematopoietic stem cell transplantation (HSCT), ADA enzyme replacement therapy (ERT) or ex vivo gene therapy (GT).Areas covered: This article discusses the different treatment options currently available for ADA deficiency, remaining challenges and expected developments.Expert opinion: Experts in ADA deficiency should manage this complex disease, as a patient’s individual factors often determine treatment course. Unconditioned HSCT from an HLA identical sibling is the preferred option. ERT can provide short-term benefits for patients without such donors, or until other definitive treatments are established. Commercial gamma-retrovirus GT, currently available only in Italy, or investigational lentivirus GT have, to date, been shown to be safe, although long-term follow up is needed t...