INTRODUCTION
Relapsed/refractory paediatric T-cell acute lymphoblastic leukaemia (T-ALL) is an aggressive, often chemo-resistant, malignancy associated with survival rates of less than 25%.1 There are few options for salvage therapy with significant short and long-term toxicities.2 In striking contrast to B-cell malignancies, there are yet to be well-established immunotherapy agents developed for the treatment of T-ALL. The challenges of developing such targeted agents lie in the heterogeneity of T-ALL blast cells on a molecular level.3,4 First identified in 1980, the transmembrane glycoprotein CD38, expressed on the surface of thymocytes and activated T-cells, has more recently emerged as a promising target.5,6 The stability of this glycoprotein’s expression despite exposure to cytotoxic chemotherapy, favours its profile as a potential target in T-ALL.7 Here we describe our experience of a patient with refractory T-ALL who received daratumumab, an anti-CD38 antibody.