Pharmacokinetic study of orally administered RU 486 in non-pregnant women

• Published in: Contraception (Stoneham) Vol. 40; no. 4; pp. 449 - 460
• Main Authors: He, Chang-hai, Shi, Yong-en, Ye, Zhi-hou, Zhang, Guo-qing, Jiang, Nai-xiong, Van Look, P.F.A., Fotherby, K.
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01.10.1989; Elsevier Science
• Subjects: Administration, Oral; Adult; Biological and medical sciences; China; Female; Genital system. Reproduction; Humans; Medical sciences; Mifepristone - administration & dosage; Mifepristone - blood; Mifepristone - pharmacokinetics; Pharmacology. Drug treatments; Population; China; Human; Steroid hormone; Abortifacient; Single dose; Oral administration; HPLC chromatography; Antagonist; Pharmacokinetics; Biology; Hormones; Research Methodology; Endocrine System; Clinical Research; Ru-486 > pharmacodynamics; Time Factors; Asia; China; Population; Developing Countries; Physiology; Eastern Asia; Hormone Antagonists; Demographic Factors; Population Dynamics
• ISSN: 0010-7824; 1879-0518
• DOI: 10.1016/0010-7824(89)90052-8

A method based on HPLC was devised for the estimation of RU 486 in blood and utilised to study the pharmacokinetics of a single dose of 50 mg RU 486 administered orally to 12 women on day 7 of the cycle. The dose was rapidly absorbed with peak plasma concentration between 1 and 2 hours. Distribution was also rapid (mean t 1 2 α: 1.4h), whereas elimination was slow (mean t 1 2 β: 28.3 h). RU 486 was still detectable in some women at 72 h after administration. The plasma concentrations fitted the equation for a two-compartment open model from which the pharmacokinetic parameters were calculated. The mean total plasma clearance was 3.0 1/h, and the comparison of our data with those published studies suggests that the pharmacokinetics of RU 486 in Chinese women are similar to those of other populations.