Novel assay format for totalanti-adeno-associated virus antibodydetection with low capsid consumption andbuilt-in specificity control: supplementary data

Aim: To develop an assay format for detection of total anti-adeno–associated virus 2 (AAV2) antibodies
with low capsid material consumption. Methods: An immune complex (IC) assay format was developed.
The format is based on the formation of ICs in solution and their subsequent detection using an anti-AAV2
antibody for capture and an antibody against the study species IgG for detection. Results: The feasibility of
the IC assay for detection of preexisting and treatment-emergent anti-AAV2 antibodies was demonstrated
in cynomolgus monkey and human serum samples, including samples from a preclinical study with AAV2-
based therapies. Conclusion: The presented IC assay is an easy-to-perform total anti-AAV2 antibody assay
that requires a small amount of unlabeled capsid material and provides an intrinsic specificity control.