Anti-idiotypic antibodies (anti-IDs) are used in preclinical and clinical research of therapeutic antibodies and biosimilars as well as in antibody drug development studies. Anti-IDs allow the reliable monitoring and quantitation of antibody drugs in clinical samples and the detection of antibody drugs that closely resemble circulating human immunoglobulins.
Monoclonal anti-IDs are routinely used as capture and detecting reagents in pharmacokinetic (PK) and pharmacodynamic (PD) assays. They are highly specific and have the advantage that time-consuming IgG depletion is not necessary. In addition, monoclonal anti-IDs provide reproducible results (lot-to-lot consistency), and can be produced endlessly.
Polyclonal anti-IDs are typically used as positive controls in immunogenicity assays. Sometimes polyclonal antibodies may also have utility as detecting reagent in PK assays and as a control in PD assays, respectively. When considering polyclonal anti-IDs, it should be taken into account that human serum contains big quantities of IgG which must first be depleted so that no anti-human-IgG antibodies are detectable.
Pharmacokinetic (PK) studies:
Anti-idiotypic antibodies are used to detect and quantify antibody drugs, antibody drug conjugates (ADCs) or biosimilars in serum.
Anti-idiotypic antibodies are used as positive control in anti-drug antibody assays (ADA assays)
Neutralization assays and blocking assays:
Anti-idiotypic antibodies are screened for their ability to neutralize or block specific ligand binding of an antibody/receptor.
We have successfully generated anti-idiotypic antibodies against different types of antibodies, e.g. human, humanized and chimeric antibodies. The development of anti-IDs is particularly challenging if the CDR region of the drug antibody is not very immunogenic, or if the serum concentration of the anti-ID is low. Another obstacle is the selection of the optimal clone. Our scientists have various solutions at hand to overcome these challenges.