Pharmacokinetics and bioavailability studies of generic ondansetron, and the innovator preparation, in healthy Thai male volunteers

• Main Authors: Rojanasthien N., Manorot M., Kumsorn B., Nawoot S., Teekachunhatean S., Sangdee C., Apisariyakul A.
• Format: Clinical Trial
• Language: English
• Published: 2014
• Online Access: http://www.ncbi.nlm.nih.gov/pubmed/3502482; http://cmuir.cmu.ac.th/handle/6653943832/3361
• Institution: Chiang Mai University

The pharmacokinetics and bioequivalence of two oral formulations of ondansetron were evaluated; Zetron (Biolab Pharmaceutical, Bangkok, Thailand), as the test formulation and Zofran (Glaxo Wellcome Operations, Greenford, UK), as the reference formulation. The two products were administered as a single oral dose of 8 mg according to a randomized two-way crossover design to 12 healthy Thai male volunteers. The washout period between treatment was 1 week. Ondansetron plasma concentrations were measured using HPLC. The oral bioavailability of ondansetron averaged 67 per cent and the elimination half-life after oral administration was 5.6 hours. The means and parametric 90 per cent CI of the ratios of Cmax and AUC 0-alpha [mu Zetron (Test)/mu Zofran (Reference)] were 0.95 (0.84-1.07) and 0.94 (0.80-1.10), respectively. These values were well within the bioequivalence range of 0.8-1.25 as established by the US-FDA. The mean difference of Tmax (Test-Reference) was approximately 20 per cent. Thus, our study demonstrated bioequivalence of the two products (Zetron and Zofran) regarding the rate and extent of absorption.