In a phase IV trial (Re:Mission Trial, NCT01347996, http://www.clinicaltrials.gov) 84 patients (age 18–79) with acute myeloid leukemia (AML) in first complete remission (CR) received ten consecutive 3-week cycles of immunotherapy with histamine dihydrochloride (HDC) and low-dose interleukin-2 (IL-2) to prevent relapse of leukemia in the post-consolidation phase. This evidence concerns the gene IL2 and leukemia.