FGF2 and chronic myelogenous leukemia, BCR-ABL1 positive: However, ponatinib, which has activity against FGF receptor and LYN kinase (12), has been shown to overcome FGF2-mediated resistance in CML patients without kinase domain mutations (16) and to be effective against many imatinib-resistant CML cell lines (19), highlighting the importance of using ponatinib as the TKI of choice for investigation of acquired BCR-ABL-independent resistance in CML.