The American Association of Pharmaceutical Scientists (AAPS) biosimilar focus group on nonclinical and clinical assays released a recent white paper entitled “Recommendations for the Development and Validation of Neutralizing Antibody Assays in Support of Biosimilar Assessment”. There are different approaches when it comes to the development and validation of neutralizing antibody (NAb) assays for biosimilar programs, and the manuscript is aimed at providing comprehensive recommendations to help scientists with the selection and requirements.

Immunogenicity assessments are a critical component to determining the comparability of an originator drug and a biosimilar. It must be demonstrated that there is no clinically meaningful difference in the incidence and severity of human immune response between the proposed and originator products. Immune responses may affect patient safety and/or product efficacy, and/or neutralize their biological activities with adverse effects. That is why it is necessary to determine both neutralizing and non-neutralizing antibody incidence for an originator drug and a biosimilar, and understand the immunogenicity’s impact on PK results as well as its association with adverse events.

Described below is one of example of approaches discussed in the white paper that can be used for NAb assessment as part of a biosimilar program.

One-Assay vs. Multiple Assay Approach: Which is Preferred?
Different opinions still exist in our industry with regard to whether a one-assay approach or two-assay approach is more appropriate for biosimilar immunogenicity assays. In our paper, the AAPS biosimilar focus group recommends using one assay for biosimilar NAb evaluation, which aligns with how the industry trend is now leaning.

A Future with Harmonized Biosimilar Bioanalytical Assessment Practices
The objective of the AAPS biosimilars focus group in developing the recent “Recommendations for the Development and Validation of Neutralizing Antibody Assays in Support of Biosimilar Assessment” paper is to contribute to the growing set of industry resources that promote the harmonization of biosimilar bioanalytical assessment practices, and to detail best practices for developing and testing NAb assays for biosimilar programs.

You can openly access the complete white paper at this link, and feel free to reach out to me if you have any questions or would like to continue this discussion.