Why PhosphoSens for AKT3 [G171R]?

A principal challenge in AKT3 drug discovery is distinguishing isoform-selective inhibition from pan-AKT activity in biochemical assays. Traditional endpoint methods such as ADP-Glo and HTRF measure single time-point signals that obscure mechanistic details and are highly sensitive to assay timing artifacts and compound interference. Radiometric assays offer sensitivity but introduce radioactive handling burdens and poor throughput. PhosphoSens continuous kinase assays overcome these limitations by generating real-time fluorescent progress curves using a sox-based peptide substrate at physiological ATP concentrations. This enables accurate Km, Vmax, and Ki determination, direct measurement of covalent kinact/KI parameters for irreversible or covalent-warhead inhibitors, and detection of slow-binding kinetics often missed at endpoint. The continuous format is fully compatible with AKT3 isoform selectivity profiling, reducing false positives and delivering mechanistically richer SAR data earlier in the discovery pipeline.