Application of a Plug-and-Play Immunogenicity Assay in Cynomolgus Monkey Serum for ADCs at Early Stages of Drug Development

Table 2

Estimation of within monkey variability across biotherapeutics. Four types of biotherapeutics were spiked in two baseline samples taken 1 week apart from 15 cynomolgus monkeys and tested in the assay. The background data from the biotherapeutic spiked samples showed that within monkey signal variability was similar. Therefore, the overall variability obtained with these four molecules could be used to estimate a generic cut point factor.

Biotherapeutic	Type of molecule	Estimated within monkey SD
ADC C	ADC	0.095
mAb 1	One-arm mAb	0.086
mAb 2	IgG1 mAb	0.096
mAb 4	IgG4 mAb	0.087
Overall		0.091

SD = estimate of within monkey signal variability.