Reply to Correspondence on “Synergy and Antagonism between Allosteric and Active-Site Inhibitors of Abl Tyrosine Kinase”

Manley and co-workers provide data demonstrating that, at super-pharmacological concentrations (300 μM), a ternary complex between Abl, asciminib, and ATP-competitive inhibitors is possible. The work in our manuscript concerns the interplay of asciminib (and GNF-2) with ATP-competitive inhibitors at pharmacologically relevant concentrations (Cmax=1.6–3.7 μM for asciminib). Manley and co-workers do not question any of the studies that we reported, nor do they provide explanations for how our work fits into their preferred model. Herein, we consider the data presented by Manley and co-workers. In addition, we provide new data supporting the findings in our Communication. Asciminib and ATP-competitive inhibitors do not simultaneously bind Abl at pharmacologically relevant concentrations unless the conformation selectivity for both ligands is matched.At pharmacologically relevant concentrations, asciminib and clinical adenosine triphosphate (ATP) kinase inhibitors cannot simultaneously bind to Abl kinase. Manley and co-workers correspond that at saturating concentrations (i.e., concentrations that are not achievable in a human), asciminib and dasatinib can simultaneously bind to Abl kinase.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/175174/1/ange202209518-sup-0001-misc_information.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/175174/2/ange202209518.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/175174/3/ange202209518_am.pd

Synergy and Antagonism between Allosteric and Active‐Site Inhibitors of Abl Tyrosine Kinase

Allosteric inhibitors of Abl kinase are being explored in the clinic, often in combination with ATP‐site inhibitors of Abl kinase. However, there are conflicting data on whether both ATP‐competitive inhibitors and myristoyl‐site allosteric inhibitors can simultaneously bind Abl kinase. Here, we determine whether there is synergy or antagonism between ATP‐competitive inhibitors and allosteric inhibitors of Abl. We observe that clinical ATP‐competitive inhibitors are not synergistic with allosteric ABL inhibitors, however, conformation‐selective ATP‐site inhibitors that modulate the global conformation of Abl can afford synergy. We demonstrate that kinase conformation is the key driver to simultaneously bind two compounds to Abl kinase. Finally, we explore the interaction of allosteric and conformation selective ATP‐competitive inhibitors in a series of biochemical and cellular assays.We describe a better understanding of the interaction between allosteric and ATP‐competitive inhibitors of Abl. Using a protease accessibility assay we developed, we determined the global conformation of Abl when bound to Abl inhibitors. We found that synergy between ATP‐competitive and allosteric inhibitors of Abl required a „matched“ kinase conformation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/169317/1/ange202105351_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/169317/2/ange202105351.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/169317/3/ange202105351-sup-0001-misc_information.pd

Reply to Correspondence on “Synergy and Antagonism between Allosteric and Active-Site Inhibitors of Abl Tyrosine Kinase”

Manley and co-workers provide data demonstrating that, at super-pharmacological concentrations (300 μM), a ternary complex between Abl, asciminib, and ATP-competitive inhibitors is possible. The work in our manuscript concerns the interplay of asciminib (and GNF-2) with ATP-competitive inhibitors at pharmacologically relevant concentrations (Cmax=1.6–3.7 μM for asciminib). Manley and co-workers do not question any of the studies that we reported, nor do they provide explanations for how our work fits into their preferred model. Herein, we consider the data presented by Manley and co-workers. In addition, we provide new data supporting the findings in our Communication. Asciminib and ATP-competitive inhibitors do not simultaneously bind Abl at pharmacologically relevant concentrations unless the conformation selectivity for both ligands is matched.At pharmacologically relevant concentrations, asciminib and clinical adenosine triphosphate (ATP) kinase inhibitors cannot simultaneously bind to Abl kinase. Manley and co-workers correspond that at saturating concentrations (i.e., concentrations that are not achievable in a human), asciminib and dasatinib can simultaneously bind to Abl kinase.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/175245/1/anie202209518_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/175245/2/anie202209518-sup-0001-misc_information.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/175245/3/anie202209518.pd