Abstract

There is an increasing need to develop drugs against traditionally intractable targets such as non-functional proteins, novel targets with unknown function or complex proteins, as well as technically challenging targets such as when lacking a purified protein for biochemical and biophysical studies. Improvements to early screening systems and optimisation of high-quality disease-relevant starting points and translational assays to to meet modern drug discovery challenge are required to accelerate the discovery and minimise late-stage drug attrition. A significant portion of projects fail in the clinic, or even fail to reach the clinic, due to lack of efficacy or failure to show the drug or lead candidate is interacting with the intended target in a more complex environment. To link target engagement to the desired phenotypic effect is fundamental in every stage of the drug discovery process. The CETSA technology is a label-free method for target engagement studies. It is used to profile direct drug interactions as well as initial pathway related events in relevant disease models of choice, including cell lines, primary cells, tissues or in vivo. The targeted CETSA format is routinely used for primary screening, hit identification, lead optimization and translational studies. Examples where an unbiased proteome-wide CETSA can be used are target ID/target deconvolution following a phenotypic screen, selectivity profiling or assessment of pathways and mechanism of action. The talk will focus on a case study of CDK4 giving insight in how CETSA can be positioned among other technologies in drug discovery from primary screening, hit identification and confirmation to selectivity profiling as well as pathways and mechanism of action assessment. We will exemplify how CETSA may be applied in various stages of drug discovery to provide data that is both actionable and biologically relevant linking target engagement to the desired phenotypic effect during drug discovery programs.