Focusing on four common hematologic malignancies (acute myeloid leukemia, multiple myeloma, chronic myeloid leukemia, and myelodysplastic syndrome), we report that GLP-1 receptor agonist use was associated with a reduced risk of multiple myeloma, whereas neither drug class was associated with significantly altered risk for hematologic malignancy in other comparisons. The gene discussed is GLP1R; the disease is plasma cell myeloma.