In late-stage lead optimization, before CD selection, a smaller set of compounds are further investigated. The aim here is to ensure that the CD (or CDs) ultimately selected is safe for clinical testing as well as suitable for formulation and that other pre-clinical drug development demands are met. This requires additional tests, such as rigorous solubility and stability analyses and safety assessments. In vivo efficacy models are used to examine the pharmacokinetic and pharmacodynamic (PK/PD) properties of the compounds for dose predictions as well as strengthening the translation and therapeutic hypothesis. The CETSA® Navigate format is particularly useful in translational studies due to the ease of transferring the assay between different cell and tissue samples. Further, the fact that this format easily allows for individual optimization and customization per compound or condition, makes it particularly useful in this stage as the projects will typically focus on a few candidate compounds.