Abstract The Pharmacokinetics/Pharmacodynamics Core (Core D) will provide analytic resources to each of the Projects in this application to measure concentrations of drugs and relevant biomarkers within various sample types. This will primarily be accomplished using a mass spectrometric approach, with which the principal investigator has significant expertise. Methods to detect drug and drug metabolites have already been developed for both the lead (P2176) and backup (P2114) compounds and successfully utilized to assess the pharmacokinetics of these drugs when applied to the airways. Similarly, methods to measure relevant biomarkers have been developed and yield biologically plausible results in preliminary experiments. Furthermore, the Core has the capability of adding new biomarkers as the need arises.