ABL1 and chronic myelogenous leukemia, BCR-ABL1 positive: Breakpoint Cluster Region–Abelson Murine Leukemia Viral Oncogene Fusion Protein (BCR-ABL) inhibitors, such as imatinib, nilotinib, and related compounds, were originally developed for the treatment of chronic myeloid leukemia (CML) and other cancers expressing the BCR-ABL fusion oncogene [1].