PDGFRA and Chronic Eosinophilic Leukemia, Not Otherwise Specified: 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.