In this study, we aimed to test the antiproliferative effect of an antidiabetic drug and oxidative phosphorylation inhibitor, metformin, in combination with first-line chemotherapy agents (cytarabine, idarubicin) or with venetoclax, a BCL2 inhibitor, and S63845—an experimental MCL1 inhibitor—on the primitive and undifferentiated CD34+ AML cell line, KG1a. Here, CD34 is linked to acute myeloid leukemia.