BIOAVAILABILITY OF ESCIN AFTER ADMINISTRATION OF 2 ORAL FORMULATIONS CONTAINING AESCULUS EXTRACT

In a steady-state cross-over study in 18 healthy volunteers, the relat ive bioavailability of beta-escin (CAS 11072-93-8) after oral administ ration of a new immediate-release enteric-coated test formulation cont aining aesculus extract was evaluated in comparison with a prolonged-r elease reference preparation. The subjects received the test and the r eference preparation in randomised sequence for 7 days each with no wa shout period in between. The daily dose was 50 mg escin b.i.d. Blood s amples for pharmacokinetic profiling were taken on the 7th treatment d ay of each period over a full 24-h cycle of two successive dosing inte rvals. For the determination of beta-escin serum concentrations, a hig hly specific radioimmunoassay (RIA) was used. Generally, escin serum c oncentrations were lower during the second dosing interval (night) tha n during the first interval, probably indicating a drug by food intera ction. (The morning dose was given after overnight fasting whereas the evening dose was given between meals). Test and reference demonstrate d bioequivalence with regard to the extent of absorption; for the AUC (0-24 h p.a.), the 90% confidence interval ranged from 84% to 114% (po int estimate: 98%). The differences observed for rate parameters can b e disregarded due to the generally slow elimination and the wide thera peutic concentration range of escin.