While drug discovery programs are traditionally focused on equilibrium-based parameters such as affinity values, drug candidates often fail in clinical trials due to on and/or off target... Show moreWhile drug discovery programs are traditionally focused on equilibrium-based parameters such as affinity values, drug candidates often fail in clinical trials due to on and/or off target toxicity and/or lack of in vivo efficacy. Receptor binding kinetics, i.e. association and dissociation rate constants, are increasingly acknowledged as better predictive parameters of in vivo drug action and it is proposed to incorporate these parameters to decrease drug attrition rates. In this thesis, the kinetic binding parameters of endogenous neuropeptides and drug candidates and their effect on signal transduction are examined to provide a better understanding of drug-target interactions. To investigate the role of binding kinetics in ligand-receptor interactions I have used two G protein-coupled receptors (GPCRs) as model systems. I have expanded the toolbox of kinetic assays which allows more accessible and high-throughput measurements of binding kinetics. Secondly, these kinetic assays enabled me to assess the kinetic binding parameters of endogenous neuropeptides and drug candidates. Lastly, I examined the role of binding kinetics in receptor activation allowing a translation into functional effects in vitro. My ambition is to transform binding kinetics into traditional, indispensable, drug discovery parameters and thereby improve the success rate of drug discovery in the future. Show less
