The plug-and-play assay showed adequate sensitivity for cynomolgus monkey studies across molecules. Pooled cynomolgus monkey serum was spiked with 5 μg/mL of eight biotherapeutics (baseline sample) or with the biotherapeutics (5 μg/mL) and 500 ng/mL of ADAs (purified cynomolgus monkey anti-human IgG). Cut points were calculated for each biotherapeutic from the signal at baseline and the generic cut point factor for a 5% false positive rate (CPF = 1.16). With all the biotherapeutics, the sample containing 500 ng/mL of ADA was positive with signals above their corresponding cut points. ADA = anti-drug antibody; ADC = antibody-drug conjugate; mAb = monoclonal antibody.