A Phase I trial of a second-generation agent, moxetumomab pasudotox (HA22, CAT-8015), with higher CD22 binding affinity and increased pre-clinical activity (Mussai et al., 2010) is in progress (NCT00659425) with early results demonstrating CRs in children with chemotherapy refractory ALL (Wayne et al., 2011). The gene discussed is CD22; the disease is acute lymphoblastic leukemia.