Variability in susceptibility - how big, how often, for what responses to what agents?

This paper surveys some recent available observations in humans on interindividual variability in exposure-related parameters, pharmacokinetics, and pharmacodynamics. Overall, I think two inferences are warranted. First, the drug and epidemiological literatures do contain information that can shed new light on the extent of variability in the doses associated with different non-cancer responses. These data are waiting to be systematically extracted and analyzed. Second, I think it is likely that with more systematic measurement and analysis of interindividual variability we are likely to find that there are systematic tendencies for some kinds of responses to some categories of agents to occur at more variable exposures/doses than others. If we gather and analyze additional data of this type, we may be able to recommend adaptive modifications to the ten-fold safety factor tuned to these differences.