LY2784544 potently inhibited the JAK2 V617F-STAT5 signaling with IC50 of 55 nM, but the IC50 for inhibiting wild type JAK2 is 2.26 uM. LY2784544 selectively inhibit the JAK2 V617F-driven cell proliferation with IC50 of 68 nM.In Ba/F3 cell model, LY2784544 can inhibit JAK2 V617F signaling and induce apoptosis with EC50 of 113 nM.