Blinatumomab Plus HLA-Mismatched Cellular Therapy for Relapsed/Refractory CD19+ ALL

Single center Phase 1 dose escalation trial of the combination of standard-of-care blinatumomab plus Haplo-Mismatched Cellular Therapy (HMCT). HMCT refers to the infusion of donor peripheral blood mononuclear cells collected via pheresis from a haploidentical family member - the procedure is analogous to giving a donor lymphocyte infusion outside of the setting of an allogeneic stem cell transplant; also known as 'microtransplantation'. The HMCT is an unselected mix of lymphocytes and leukocytes, but the product dose escalation will be done based on the T cell content. Ten recipients are planned. Each subject will be administered one infusion of HMCT during the first cycle of blinatumomab and two infusions during cycle two of blinatumomab; the CD3+ cell dose of the HMCT infusion is governed by dose escalation / de-escalation following a Bayesian method.