Immunogenicity testing in biosimilars Posted 24/01/2014

During a presentation given by Dr Kelly Colletti (Laboratory Sciences, USA) at an international conference on biowaivers and biosimilars, held in the US in September 2012, it was discussed whether one or two assays should be employed in order to measure anti-drug antibodies to both the biosimilar and reference biological in a comparative manner [1].
One topic highlighted during the presentation was how the strategy used for immunogenicity testing may have an impact on the immunogenicity rates observed and, therefore, impact the ability to correlate the anti-drug antibody results with the pharmacokinetic results. The potential impact was highlighted by the example of an immunogenicity assay designed to detect antibodies to the biosimilar and the reference biological using the biosimilar coated on the plate. However, using this approach, antibodies unique to the reference biological may not be detected by the assay. Although this risk of missing some immunogenicity may be acceptable based upon the existing patient safety data for the reference biological in the population tested it may cause correlation with the pharmacokinetic data to be distorted. In addition, this analysis design may not adequately characterize a decreased immunogenicity rate for the biosimilar in comparison with the reference biological, which could potentially indicate that the biosimilar is superior to the reference biological. Although one might think that is not a problem – when trying to prove ‘similarity’ proving ‘superiority’ is a problem. Related articles Protein aggregation and the generation of immune responses Bioanalytical challenges in the development of biosimilars Analysis of carbohydrate containing biosimilars Reference 1. Colletti KS. Conference Report: Bioanalysis-related topics presented at the International Conference and Exhibition on Biowaivers and Biosimilars. Bioanalysis. 2013;5(5):529-31. Permission granted to reproduce for personal and non-commercial use only. All other reproduction, copy or reprinting of all or part of any ‘Content’ found on this website is strictly prohibited without the prior consent of the publisher. Contact the publisher to obtain permission before redistributing. Copyright – Unless otherwise stated all contents of this website are © 2014 Pro Pharma Communications International. All Rights Reserved.