GNF-5, an analogue of GNF-2 with improved pharmacokinetic properties, is a selective non-ATP competitive inhibitor of Bcr-Abl with an IC50 value of 0.22±0.1 uM (Wild type Abl).

GNF-5 is a cell-permeable GNF-2 N-hydroxyethyl carboxamide analog that exhibits in vivo efficacy in suppressing the proliferation of Bcr-abl-expressing Ba/F3 (93% and 83% of no-treatment control, respectively, on days 5 and 7 post treatment; 100 mg/kg b.i.d.) and bone marrow cells (~75% of no-treatment control in both WBC counts and spleen weight on day 7 post treatment; 50 mg/kg b.i.d.) in murine xenograft models of leukemia. Similar to GNF-2, GNF-5 exerts its effect via an allosteric mechanism (IC50 = 0.22 ?M against wild-type Abl) by targeting the myristate-binding pocket near the c-terminus of Abl kinase domain and thereby altering the conformational dynamics of the ATP-binding pocket. GNF-5 is ineffective toward the myristate-binding site mutant E505K and the ATP-binding site 'gatekeeper' mutant T315I.