Most of the studies showing that OCT1 is important for imatinib uptake and molecular response in CML patients used prazosin and amantadine as OCT1 inhibitors.5, 28 However, in accordance with recently published data,10 prazosin and amantadine are not specific inhibitors for OCT1 but have similar or even higher affinities to MATE1 than to OCT1 (Supplementary Table 1). The gene discussed is SLC47A1; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.