High-Throughput Screening for the Discovery of Enzyme Inhibitors

Enzymes
are common targets in high-throughput screening and related
campaigns. An analysis of papers published between 1990 and 2018 showed
that kinases were the most common enzymes investigated, fluorescence-based
assays were the most common readout method, and cancer and bacterial
infections were the most common therapeutic areas. High-throughput
screening and fragment-screening campaigns published between 2017
and 2019 were analyzed in more depth, giving 75 examples of hit to
lead development. Kinases, phosphatases, proteases, and peptidases
were the most common targets, fluorescent assays were the most commonly
used, and a wide variety of structural features were observed within
the derived drugs. Hit frequency was largely independent of library
size and positively correlated with Z′ value
for the assay. Binding of metal ions to library compounds and substrates
is an underappreciated source of false-positive results and unreproducible
behavior.