Determinants of Drug ADME -- Enzymatic Basis of Phase I and Phase II Drug Metabolism -- Transporters: Importance in Drug Absorption, Distribution, and Removal -- ADME Pharmacogenetics and Its Impact on Drug-Drug Interactions -- Impact of Nuclear Receptors CAR, PXR, FXR, and VDR, and Their Ligands On Enzymes and Transporters -- Impact of Physiological Determinants: Flow, Binding, Transporters and Enzymes on Organ and Total Body Clearances -- Methods For The Study Of Drug-Drug Interactions -- In Silico Approaches to Predict DDIs -- In Vitro Techniques to Study Drug-Drug Interactions of Drug Metabolism: Cytochrome P450 -- The In Vitro Characterization of Inhibitory Drug-Drug Interactions Involving UDP-Glucuronosyltransferase -- In Vitro Techniques to Study Transporter-Based DDI -- In Vitro Techniques to Study Drug-Drug Interactions Involving Transport: Caco-2 Model for Study of P-Glycoprotein and Other Transporters -- Use of In Vivo Animal Models to Assess Drug-Drug Interactions -- Extrapolation of In Vitro Metabolic and P-Glycoprotein-Mediated Transport Data to In Vivo by Modeling and Simulations -- Translation of In Vitro Metabolic Data to Predict In Vivo Drug-Drug Interactions: IVIVE and Modeling and Simulations -- Absorption Models to Examine Bioavailability and Drug-Drug Interactions in Humans -- Management of Drug Interactions of New Drugs in Multicenter Trials Using the Metabolism and Transport Drug Interaction Database© -- Web-Based Database as a Tool to Examine Drug-Drug Interactions Involving Transporters -- Impact Of Drug-Drug Interactions -- Drug Disposition and Drug-Drug Interactions: Importance of First-Pass Metabolism in Gut and Liver -- Transporter-Based Drug-Drug Interactions and Their Effect on Distribution Volumes -- Inactivation of Human Cytochrome P450 Enzymes and Drug-Drug Interactions -- Allosteric Enzyme- and Transporter-Based Interactions -- The Impact and In Vitro to In Vivo Prediction of Transporter-Based Drug-Drug Interactions in Humans -- Herbal Supplement-Based Interactions -- Anticipating and Minimizing Drug Interactions in a Drug Discovery and Development Setting: An Industrial Perspective -- Clinical Studies of Drug-Drug Interactions: Design and Interpretation -- Toxicological Consequences of Drug-Drug Interactions -- Regulatory Aspects And Future Developments Involving DDI -- Complex Drug Interactions: Significance and Evaluation -- Drug-Drug Interactions: Communicating Post-market Drug Safety Information in the USA -- Drug-Drug Interactions: What Have We Learned and Where Are We Going?. This volume is authored by esteemed experts in the field, and provides state-of-the art knowledge related to enzyme- and transporter-based DDIs that impact the absorption and disposition of drugs. It examines the types of DDIs, methodological approaches to evaluate and view DDIs mechanistically, bioinformatics, clinical and toxicological outcomes, and regulatory recommendations. As much as possible, the future challenges and opportunities that lie ahead are presented and discussed. Special emphases are placed on the quantitative assessment of the roles of different transporters, need for more specific probes and inhibitors, and recognition of extrahepatic eliminating organs. Future approaches should integrate transporters and enzymes to accelerate the development of physiological based-pharmacokinetic models (PBPK-DDI) and information related to inter-subject variability. In addition, the authors look beyond small molecules and consider DDIs involving biologic agents, such as therapeutic antibodies, that can bring about pharmacologically significant drug-cytokine or drug-endocrine interactions.