Single-dose pharmacokinetic study comparing the pharmacokinetics of recombinant human chorionic gonadotropin in healthy Japanese and Caucasian women and recombinant human chorionic gonadotropin and urinary human chorionic gonadotropin in healthy Japanese women

PurposeRecombinant hCG (r-hCG) was approved in Japan in 2016. As a prerequisite for a Phase III study in Japan related to this approval, the pharmacokinetic (PK) profile of r-hCG was investigated. MethodsAn open-label, partly randomized, single-center, single-dose, group-comparison, Phase I PK-bridging study was done that compared a single 250g dose of r-hCG with a single 5000IU dose of urinary hCG (u-hCG) in healthy Japanese women, as well as comparing a single 250g dose of r-hCG in Japanese and Caucasian women. The Japanese participants were randomized 1:1 to receive either r-hCG or u-hCG, while the Caucasian participants were weight-matched to the Japanese participants who were receiving r-hCG in a 1:1 fashion. The primary PK parameters were the area under the serum concentration-time curve from time 0 extrapolated to infinity (AUC(0-)) and the maximum serum concentration (C-max). ResultsThe mean serum hCG concentration-time profiles of r-hCG in the Japanese and Caucasian participants were a similar shape, but the level of overall exposure was similar to 20% lower in the Japanese participants. For the Japanese participants, r-hCG resulted in an 11% lower C-max but a 19% higher AUC(0-) compared with u-hCG. No new safety signal was identified. ConclusionThis study cannot exclude a potential difference in the PK profile of r-hCG between Japanese and Caucasian participants. However, this study does not indicate that there are clinically relevant differences in the serum PK of r-hCG and u-hCG in the Japanese participants.