Rational design of anti-dementia therapy

Abstract

Understanding the pharmacokinetic (PK) and pharmacodynamic (PD) characteristics of new drugs is essential. The application of this information facilitates the design of a rational clinical trial programme and optimizes the chances for rapid and successful clinical development. Upon completion of each development phase, the information obtained must be evaluated critically to maximize the design of subsequent studies. Phase I trials represent the first time the drug is administered in humans and their primary objective is to evaluate the drug's safety and tolerability in man. Phase II trials represent the first time that the drug is administered to the target patient population. The objectives of Phase II trials are to verify the safety and tolerability of the drug in patients, and also to evaluate for the first time the clinical efficacy of the drug. During these phases of development, the use of PK and PD measures is helpful for establishing the therapeutic dose range as well as the suitability of the chosen efficacy measures for use in the pivotal Phase III trials. Here, using several examples of PK and PD data obtained from the clinical development studies of donepezil HCl, the application of these measures on the development of a drug for the treatment of Alzheimer's disease is discussed.