ABCB1 and chronic myelogenous leukemia, BCR-ABL1 positive: While there were also reports that combinations of genetic variants in ABCB1 with other drug transporters, mainly OCT1 and ABCG2 occurred in high frequency and lead to the reduced response of CML patients to imatinib (Galeotti et al., 2017; Yin et al., 2016).