ABSTRACT
As discussed in the previous chapters, the assessment of bioequivalence and/or biosimilarity is very sensitive to bioequivalence/biosimilarity criteria. The one-size-fits-all criterion for the assessment of bioequivalence for small-molecule drug products has been criticized and considered not to be appropriate for the assessment of biosimilarity. However, little or no information regarding what criteria are most appropriate for the assessment of biosimilarity is available in regulatory guidances. Without a well-defined and widely accepted biosimilarity criterion, it is difficult to demonstrate that the test product is highly similar to the reference product. To overcome this problem, Kang and Chow (2013) suggested considering the evaluation of relative distance between T-R and R-R and proposed useful statistical methods for the assessment of biosimilarity based on the defined relative distance as described in the previous section. The methods proposed by Kang and Chow, however, still depend upon the selection of biosimilarity criteria.
