Current Issues In Analytical Similarity Assessment

In 2017, Food and Drug Administration (FDA) circulated a draft guidance on analytical similarity assessment to assist the sponsors for providing totality-of-the-evidence in support of the demonstration of biosimilarity between a proposed biosimilar product and an innovative biological product. The guidance was subsequently withdrawn by the FDA due to some major criticisms received from general public. These major criticisms include, but are not limited to, (i) the use of 90% confidence interval (CI) versus 95% CI, (ii) tiered approach for analytical similarity evaluation, and (iii) current practical issues related to analytical similarity assessment. In this article, these major criticisms and issues are discussed. In addition, some recommendations regarding alternative thinking or methods for analytical similarity evaluation are provided.