Brierley et al. reported a decline in Hb levels in all patients (median Hb change, −1.0 g/dL; range, 0.4–1.6) and increased transfusion requirements with the administration of anti-CD47 Hu5F9-G4 in a phase 1 study of nineteen patients with relapsed/refractory AML (NCT02678338). This evidence concerns the gene CD47 and acute myeloid leukemia.