Related to the increasing number of biological/biotechnology-derived proteins used as therapeutic agents, these proteins and the immunogenicity increasingly got into the focus of scientists and regulators, as shown with the news on the "Immunogenicity Assessment for Therapeutic Protein Products" and "Draft guideline on immunogenicity assessment of biotechnology-derived therapeutic proteins 2016".
If therapeutic protein products were applied to a patient, possible immune responses can influence the product safety and efficacy. The clinical effects of patient immune responses are highly variable, ranging from no effect at all to extremely harmful effects to patient health. Therefore, the detection and analysis of anti-drug antibodies can be an important tool to understand such immune responses. This understanding is basic and crucial for any therapeutic protein product development program.
In April, the FDA issued a Draft Guidance for Industry "Assay Development and Validation for Immunogenicity Testing of Therapeutic Protein Products". They defined in their introduction:
"This guidance provides recommendations to facilitate industry's development and validation of immune assays for assessment of the immunogenicity of therapeutic protein products during clinical trials. Specifically, this document includes guidance regarding the development and validation of screening assays, confirmatory assays, titering assays, and neutralization assays. For the purposes of this guidance, immunogenicity is defined as the propensity of the therapeutic protein product to generate immune responses to itself and to related proteins or to induce immunologically related adverse clinical events. The recommendations for assay development and validation provided in this document apply to assays for detection of anti-drug antibody(ies). This guidance may also apply to some combination products on a case-by-case basis.
This document does not discuss the product and patient risk factors that may contribute to immunogenicity. This guidance, including any discussions of terminology used in this guidance, does not apply to in vitro diagnostic products.This guidance revises the draft guidance for industry Assay Development for Immunogenicity Testing of Therapeutic Proteins issued in December 2009. The information in this guidance has been reorganized for clarity and includes new information on titering and confirmatory assays."
For more details please read the complete document "Assay Development and Validation for Immunogenicity Testing of Therapeutic Protein Products"