PDA Letter Article

Know Your Numbers for Analytical Similarity

by Emanuela Lacana, PhD, U.S. FDA

Ampules

Despite an increase in the approval of biosimilars in the United States, the development of biosimilar products continues to be challenging. Some questions about them have been partially resolved, such as the number of lots needed for the analytical similarity exercise, while others are still under discussion.

Many questions remain regarding statistical analysis. To assist manufacturers, the U.S. FDA issued a draft guidance on statistical approaches to evaluating analytical similarity that clarifies several aspects of the statistical analysis; however, challenges remain when it comes to the use of statistical tools. For example, what does it mean for analytical similarity when an attribute does not meet statistical analysis criteria?

Members can read the full article in the April 2018 PDA Letter (PDF)