Hi Asma,
Do you mean you have a positive control for your ADA assay, but it isn't neutralizing, or do you mean you have no PC at all?
If you have an ADA assay and a free PK or PD assay that would be sensitive to neutralizing antibodies you can consider not developing a specific assay to measure NAb but rather integrate the data sets of PK, PD and ADA. This approach is supported by regulatory agencies and is described in the 2019 FDA immunogenicity guidance1. You said your drug is a MAb, it would be important to assess the potential risks of immunogenicity to determine what approaches to characterizing NAb could work for you.
1. Immunogenicity Testing of Therapeutic Protein Products - Developing and Validating Assays for Anti-Drug Antibody Detection. 2019
"In selected cases, where there is a highly sensitive PD marker or an appropriately designed PK assay or both that generate data that inform clinical activity, it may be possible to use these in lieu of a NAb assay. This determination should be done in consultation with the Agency."
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Christopher Stebbins PhD
Scientific Director
Immunologix Labs
Tampa FL
[email protected]Disclaimer: Opinions expressed are solely my own and do not express the views or opinions of my employer.
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Original Message:
Sent: 12-13-2023 19:28
From: Asma Ejaz
Subject: Neutralizing antibody Assay for mAb
Hi All,
I need some help to develop a neutralizing antibody assay for mAb in the absence of real positive control. Any reference would be great.
Thank you in advance.
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Asma Ejaz, Ph.D.
Associate Director
Celldex Therapeutics
[email protected]
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