ABL1 and chronic myelogenous leukemia, BCR-ABL1 positive: Imatinib (Gleevec), which selectively targets the ATP binding site of the BCR-ABL protein, is a first generation BCR-ABL tyrosine kinase inhibitor (TKI) that was approved in 2001 by the FDA for treating CML (Gontarewicz et al., 2008; Wu et al., 2014).