Physiologically based pharmacokinetic modeling of SNU-0039, an anti-Alzheimer's agent, in rats

The objective of this study was to characterize the systemic and tissue kinetics of 2-(3,4-dimethoxyphenyl)-5-(3-methoxypropyl) benzofuran (SNU-0039), an inhibitor of β-amyloid protein aggregation, in rats. Simultaneous fitting of the data to polyexponential equations indicated that the systemic clearance and steady state volume of distribution were estimated to be 0.0220 l/min/kg and 2.33 l/kg. The clearance and volume of distribution were not dependent on the intravenous dose, in the range from 5 to 20 mg/kg. The tissue (i.e., the brain, liver, kidneys, heart, spleen, lungs, gut, muscle and adipose tissue) to plasma partition coefficients (K(p)) for SNU-0039 in rats ranged from a low of 0.779 ± 0.314 (muscle) to a high of 5.71 ± 1.66 (liver). The recoveries of DMB were less than 1% of the dose for the renal and biliary excretion, indicative of minor involvements of these pathways in overall elimination. The fraction of bound SNU-0039 to plasma protein was approximately 95.9% and the fraction of SNU-0039 distributed to blood cells was approximately 45.3%. Assuming a flow-limited distribution, the simulated concentration profiles for SNU-0039 in the physiologically based pharmacokinetic model were in reasonable agreement with the observed concentrations in plasma and nine tissues in rats.