Clinical Laboratory Reference Values for Caucasian Studies in Japan

Abstract

BackgroundClinical laboratory values are critical indicators for clinical trials from beginning of enrolments for rightful subjects to monitoring the subject's safety. However, actual values may vary significantly due to differences in assay methodologies and standardization even within a country. Therefore, when conducting clinical trials with Caucasian subjects in non-Caucasian native countries such as Japan, it is even more important to understand and consider the ethnicity differences in laboratory values to minimize bias and obtain the best results. In this study, to define the reference ranges for Caucasian healthy subjects for clinical trials in Japan, we reviewed and analyzed clinical laboratory data from our healthy Caucasian studies. The characteristics of clinical laboratory reference intervals were evaluated and compared between Caucasian and Japanese volunteers. Methods Clinical laboratory data for Caucasian volunteers (524 Males, 29 Females) from the screening tests for clinical trials at SOUSEIKAI Sumida Hospital from Jan 2017 to Dec 2017 and assessed hematological and clinical chemistry data with a focus on Hepatic and Lipid Panels. The clinical laboratory reference intervals were compared to the values for same age and gender group of Japanese volunteers. Also, we evaluated the values in different age groups to investigate the impact of age factors over ethnicity factors. Results A total data of 524 healthy Caucasian volunteers aged 20 to 45 years for 11 parameters were reviewed and analyzed; AST, ALT, ALP, T-Bil, LDH, gamma-GT, TG, LDL-C. HDL-C, Creatine, TCh, There were statistically significant differences between Japanese and Caucasian data in CK and LDL-C for male volunteers whereas other indicators showed similar ranges. The laboratory values for ALT, ALP, in Caucasian males were somewhat higher than those from Japanese males and TG was higher in Japanese males compare to Caucasian males. Also, our reference ranges for Caucasian volunteers were consistent with established intervals from the US (Massachusetts General Hospital, MGH-USA) ConclusionBy defining and understanding the right clinical laboratory reference intervals for Caucasian healthy subjects, it is possible to assess participant's eligibility and safety for clinical trials, avoiding unnecessary exclusion of eligible participants and over-reporting of adverse events (AEs) for Caucasian studies in Japan.