Ursodeoxycholic acid complexation with 2-hydroxypropyl-β-cyclodextrin increases ursodeoxycholic acid biliary excretion after single oral administration in rats

Complexation of ursodeoxycholic acid (UDCA) with 2-hydroxypropyl-beta -cyclodextrin (HP beta CD) improves the water solubility and the dissolution rate of UDCA and may therefore increase its bioavailability. We compared the amount and the rate of biliary excretion of UDCA and biliary lipid secretion after a single oral administration of UDCA in 3 different pharmaceutical formulations [UDCA-HP beta CD ('urso-beta -cyclodextrin'), UDCA suspension and UDCA capsule] at 3 different dosages each, in 11 groups (2 control groups) of bile fistula rats. UDCA excretion increased with an increase in dose, biliary UDCA recovery and peak secretion were significantly higher after administration of UDCA-HP beta CD than after UDCA in suspension or capsule. This enhancement of biliary excretion may achieve greater UDCA enrichment in the bile acid pool than conventional pharmaceutical UDCA formulations, this giving to UDCA-HP beta CD a considerable therapeutical potential, Copyright (C) 2001 S. Karger AG, Basel.