Comparison of the NIDS® rapid assay with ELISA methods in immunogenicity testing of two biotherapeutics.
BACKGROUND
Rapid lateral flow immunogenicity assays for the detection of anti-drug antibodies (ADAs) to two biotherapeutic antibodies, an anti-HER2 antibody and an anti-TNF-α antibody, were developed using ANP Technologies, Inc.'s proprietary Nano-Intelligent Detection System (NIDS®) and compared to their ELISA counterparts.


METHODS
Biotin and hapten-labeled drugs are incubated with the patient serum sample to allow ADA to form a bridge complex with each drug conjugate. The reaction mixture is then added to a test strip with an anti-hapten capture zone which captures the mixed bridge complex. The bridge-complexed biotinylated drug then reacts with streptavidin-labeled gold particles in situ. The signal developed at the capture zone, which is directly proportional to ADA in the sample, is then quantitatively measured with a handheld reader. The counterpart ELISAs were run using the same reagents. Dose-response, specificity/free drug depletion, and screening cut-point assays were performed using both methods.


RESULTS
The rapid assays' performance compare very closely to their ELISA counterparts'. Both types of assays identified the same positive samples in screening a limited population of 50 normal serum samples for the anti-HER2 antibody. In the case of anti-TNF-α, both assays identified the same positive samples out of 50 normal and 20 rheumatoid arthritis patient serum samples but differed in the assessment of two others. The rapid assay correctly identified as negative an ELISA false positive sample, and correctly tested as positive an ELISA false negative sample. Positive results were verified with a specificity/free drug depletion assay.


CONCLUSIONS
The NIDS® rapid immunogenicity assay offers distinct advantages over current methods in simplicity, low cost, and short time to result. More importantly, the method requires no sample dilution and no washing steps which can perturb fragile complexes formed by low-affinity ADAs. Thus, the assay can potentially detect ADAs with various affinities.
Pan
Jing
J
ANP Technologies, Inc. 824 Interchange Blvd., Newark, DE 19711, USA.
Small
Thomas
T
Qin
Dujie
D
Li
Shawn
S
Wang
Li
L
Chen
Dave
D
Pauley
Cindy
C
Verch
Thorsten
T
Kaplanski
Catherine
C
Bakhtiar
Ray
R
Vallejo
Yli Remo
YR
Yin
Ray
R
D000906:Antibodies / Q000276:immunology; D000917:Antibody Formation / Q000276:immunology; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000276:immunology; D004306:Dose-Response Relationship, Immunologic; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D006801:Humans; D007125:Immunogenetics / Q000379:methods*; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology
D000906:Antibodies; D018719:Erb-b2 Receptor Tyrosine Kinases; D014409:Tumor Necrosis Factor-alpha; C508053:ERBB2 protein, human