Allometric issues in drug development

The concept of correlating pharmacokinetic parameters with body weight from different animal species has become a useful tool in drug development. The allometric approach is based on the power function, where the body weight of the species is plotted against the pharmacokinetic parameter(s) of inter est. Clearance, volume of distribution, and elimination half-life are the t hree most frequently extrapolated pharmacokinetic parameters. Over the year s, many approaches have been suggested to improve the prediction of these p harmacokinetic parameters in humans from animal data. A literature review i ndicates that there are different degrees of success with different methods for different drugs. Overall, though interspecies scaling requires refinem ent and better understanding, the approach has lot of potential during the drug development process.