3.2 Differences in Response Doses
There is mismatch between administration of doses and levels of
phytochemicals / chemopreventive agents in circulating tissue in animal
vs. human. Doses delivered to animals/kg of their body weight are
especially high in contrast with doses given to human in clinical
trials.
For example Curcuminoid’s at high doses [around 6 g/day fractionate
into 3 doses] for 12 days was found to be more effective in arbitrary
placebo controlled study while lower doses [2g/day of turmeric
extract, fractionate in 2 doses] for 7 weeks were found to be
ineffective in HNC (Chainani-Wu et al. , 2012). This
pharmacokinetic profile is peculiar to the dose range tested in the
experimental species (strain of animal used). The known interspecies
differences and metabolic differences between species must be
accommodated. For integrated pharmacokinetic, studies allometric scaling
between species is needed for accurate detailed differences in plasma
protein binding and metabolic stability.