Pharmacokinetics and safety of transdermal and oral granisetron in healthy Chinese subjects: An open-label, randomized, crossover study

To examine the pharmacokinetics and safety of granisetron during transdermal delivery and oral administration to healthy Chinese male subjects.A single 34.3 mg/52 cm2 transdermal delivery patch of granisetron and the 1-mg tablet of granisetron were dosed to subjects in an open-label, randomized, crossover study. Two dosing schemes were established: scheme 1, in which the 5-day oral administration phase of the tablet (the OA phase) (twice daily every 12 hours) was conducted, followed by the 6-day transdermal delivery phase of the patch (the TD phase); and scheme 2, in which these two phases were conducted in reverse order. Plasma concentrations of granisetron were measured according to high-performance liquid chromatography, and the following pharmacokinetic parameters were determined: Cavg [AUC0-24,ss (day 5)/24 for OA and AUC24-144/120 for TD], Cmax, tmax, AUC, and T1/2.All of the subjects completed the TD phase, and 1 subject withdrew from the study due to increased alanine aminotransferase. The Cavg values for OA and TD were 2.95 ± 1.60 ng/mL and 2.83 ± 1.43 ng/mL, respectively. The Cmax values at steady state for OA and TD were 5.98 ± 2.27 ng/mL and 3.91 ± 2.23 ng/mL, respectively. The incidences of adverse events (AEs) possibly or definitely related to OA and TD were 45.83% and 37.5%, respectively. No serious AEs were found in the two dosing schemes.The Cavg values determined through TD and OA were equivalent, indicating similar drug exposures. Therefore, the granisetron patch may be an alternative formulation for oral granisetron in Chinese individuals. .