Simultaneous confidence interval methods for analytical similarity assessment.

In analytical similarity assessment of a biosimilar product, key quality attributes of the test and reference products need to be shown statistically similar. When there were multiple references, similarity among the reference products is also required. We proposed a simultaneous confidence approach based on the fiducial inference theory as an alternative to the pairwise comparison method. Three versions with two types of simultaneous confidence intervals for each version were proposed based on different assumptions of the population variance. We conducted extensive simulation studies to compare the performance of our proposed method and the pairwise method, and provided examples to illustrate the concern of using pairwise method.