Demonstrating biosimilar and originator antidrug antibody binding comparability in antidrug antibody assays: a practical approach

Biosimilar drug developmenthas brought new challenges to bioanalytical ligand-binding assaysused to determine drug concentration, antidrug antibodies and neutralizing antibodies. One particular challenge is how to demonstrate that the antidrug antibody assay can adequately detect antibodies against both biosimilarand originator. In this paper, we review the current guidelines and literature for practical recommendations and present a gap analysis. Case examples of antibody binding comparability testing are presented, and the challenges and implications are discussed. Based on the lessons learned from our biosimilarassay applications, we recommend a bioanalytical comparability testing approach that is outlined and discussed.