Method for measuring anti-drug antibody

A method for detecting anti-drug antibodies (ADAs) to a drug in an analyte, the method comprising:

• (1) providing a sample comprising an analyte to be measured for ADAs by adding the drug to the analyte to be measured for ADAs to yield a sample comprising drug-ADAs immune complexes;
• (2) after (1), contacting the sample with a carrier coated with complement Clq, anti-C3d antibody, or anti-Clq antibody to capture the drug-ADAs immune complexes;
• (3) after (2), washing the coated carrier to exclude free-form drug;
• (4) after (3), contacting a labeled or non-labeled antibody specific to the drug with the drug-ADAs immune complexes captured with the coated carrier;
• (5) after (4), washing the coated carrier to exclude unbound labeled or non-labeled antibody specific to the drug;
• and
• (6) after (5) detecting the drug-ADAs immune complexes binding to the complement Clq, anti-C3d antibody, or anti-Clq antibody with the labeled or non-labeled antibody specific to the drug by at least one immunoassay selected from the group consisting of enzyme immunoassay, chemiluminescence method, immunochromatography, plasmon resonance, fluorescence method, radioimmunoassay, immunoradiometric assay, fluorescence polarization immunoassay, immunonephelometry, latex agglutination turbidimetru, latex agglutination inhibition immunoassay, and time-resolved fluorescence immunoassay.