Since CML drug resistance is usually acquired by overexpression of or mutation in tyrosine kinase BCR-ABL, 293T-derived IL3R-expressing exosomes were encapsulated with BCR-ABL inhibitor imatinib or BCR-ABL siRNAs, and they were shown to inhibit CML growth and drug-resistance in vivo. Here, ABL1 is linked to chronic myelogenous leukemia, BCR-ABL1 positive.