Lierman et al. found that the drug has antiproliferative activity on Ba/F3 cells expressing the imatinib-resistant FIP1L1-PDGFRαT674I or the pan-resistant FIP1L1-PDGFRα-D842V, which have been detected in a number of patients affected by CEL. This evidence concerns the gene FIP1L1 and Chronic Eosinophilic Leukemia, Not Otherwise Specified.