ADCs including the PBD-conjugated loncastuximab, have prominent activity in hematologic malignancies (8, 9, 22, 23), but the currently available ADCs such as the anti-CD33 ADC gemtuzumab, show limited activity in high-risk MDS/AML and TP53-mutated disease (10). The gene discussed is CD33; the disease is acute myeloid leukemia.