View our latest publication, “A High-Throughput Method for Measuring Drug Residence Time Using the Transcreener® ADP2 Assay” in SLAS Discovery.
Inhibitor residence times are increasingly being used to prioritize molecules early in lead discovery programs. Current methods for determining residence time are low-throughput or require the synthesis of labeled ligands. Our goal was to create an HTS compatible assay method that was broadly applicable to protein kinases. Senior Application Scientist, Meera Kumar, used the “jump dilution” kinetic approach with the Transcreener® ADP Kinase Assay to estimate residence times by continuously monitoring kinase enzymatic activity as inhibitors dissociated. The ability to determine residence times in an HTS format opens the door to characterizing more compounds earlier in discovery.
Residence time, the time that an inhibitor is bound to a target, is the reciprocal of the dissociation rate (1/koff). Here, we demonstrated residence time measurements for a number of known inhibitors for EGFR, ABLI, and Aurora kinases. In the study, the rank order of koff values correlated well with published values, but some absolute values were quite different, most likely due to differences inherent in the methods. We also showed similar results between the three fluorescent detection readouts (FP, FI, and TR-FRET) available with the Transcreener® ADP2 Kinase Assay. The data validates the assay method as a universal approach for estimating drug residence times with the ability to use a variety of fluorescent readouts in an HTS format.
To learn more, please read the full publication.