Fit-for-purpose validation of a drug-tolerant immunogenicity assay for a human mAb drug in animal safety studies.

A modified biotin-drug extraction and acid dissociation (BEAD) immunogenicity assay was developed to detect anti-drug-antibodies (ADA) against the human anti-FXIIa monoclonal antibody (mAb) drug, Garadacimab (previously called CSL312). Multiple strategies were tested to optimize the signal-to-background (S/B) ratio, assay sensitivity and the drug tolerance. The modified BEAD assay was found to be highly drug tolerant (>500 μg/ml) with a sensitivity of 100 ng/ml, in line with current FDA regulatory guidelines.

Airway inflammation and dysbiosis in antibody deficiency despite the presence of IgG.

Background: Patients with antibody deficiency suffer chronic respiratory symptoms, recurrent exacerbations, and progressive airways disease despite systemic replacement of IgG. Little is known about the respiratory tract biology of these patients.

Objective: We sought to measure immunoglobulin levels, inflammatory cytokines, and mediators of tissue damage in serum and sputum from patients with antibody deficiency and healthy controls; to analyze the respiratory microbiome in the same cohorts.