Sample size and statistical analysis
Sample size was determined based on the intrasubject variability of
Cmax,ss and AUCτ,ss of evogliptin and
glimepiride from previous studies in healthy subjects. The sample size
of 32 was calculated in order to detect 20% differences in PK
parameters ensuring a statistical power of 80%, with a significance
level of 5% under the assumptions that the maximum of intra-subject
coefficient of variation for PK parameters of evogliptin or glimepiride
was 33%. Considering possible dropouts, 36 subjects were chosen as the
final sample size.
To evaluate the PK interactions between evogliptin and glimepiride, the
geometric mean ratios (GMRs) and 90% confidence intervals (90% CIs)
for the Cmax,ss and AUCτ,ss of the
combination therapy to the monotherapy (EVO+GLI/GLI or EVO+GLI/EVO) were
calculated from the analyses of variance (ANOVA) model, with sequence,
period and treatment as fixed effects.