Selection of a Ligand-Binding Neutralizing Antibody Assay for Benralizumab: Comparison with an Antibody-Dependent Cell-Mediated Cytotoxicity (ADCC) Cell-Based Assay

Abstract

Assessment of anti-drug antibodies (ADAs) for neutralizing activity is important for the clinical development of biopharmaceuticals. Two types of neutralizing antibody (NAb) assays (competitive ligand-binding assay [CLBA] and cell-based assay [CBA]) are commonly used to characterize neutralizing activities. To support the clinical development of benralizumab, a humanized, anti-interleukin-5 receptor α, anti-eosinophil monoclonal antibody, we developed and validated a CLBA and a CBA. The CLBA and CBA were compared for sensitivity, drug tolerance, and precision to detect NAbs in serum samples from clinical trials. The CLBA was more sensitive (27.1 and 37.5 ng/mL) than the CBA (1.02 and 1.10 μg/mL) in detecting NAbs to benralizumab for the polyclonal and monoclonal ADA controls, respectively. With the same polyclonal ADA control, the CLBA detected 250 ng/mL of ADA in the presence of 100 ng/mL of benralizumab, whereas the CBA detected 1.25 μg/mL of ADA in the presence of 780 ng/mL of benralizumab. In 195 ADA-positive samples from 5 studies, 63.59% (124/195) and 16.9% (33/195) were positive for NAb as measured by the CLBA and the CBA, respectively. ADA titers were strongly correlated (Pearson's correlation coefficient r = 0.91; n = 195) with CLBA titers. Moreover, the CLBA titer correlated with CBA percentage inhibition in the CBA-positive samples (Spearman's coefficient r = 0.50; n = 33). Our data demonstrated advantages of the CLBA in various aspects and supported the choice of the CLBA as a NAb assay for the phase III trials.

Effectiveness of benralizumab for allergic and eosinophilic predominant asthma following negative initial results with omalizumab

“…In our case, benralizumab immediately improved the asthma symptom control and sinusitis after a negative initial response to omalizumab. Benralizumab strongly induces antibody‐dependent cell‐mediated cytotoxicity (ADCC) of eosinophils and basophils , and is effective for not only asthma symptom control but also sinusitis. In this overlapping patient population, there is no objective, evidence‐based answer to the question “Is anti‐IgE or anti‐IL‐5 the first choice?” A prospective large‐scale randomized study comparing these drugs might be of interest.…”

2020 White Paper on Recent Issues in Bioanalysis: Vaccine Assay Validation, qPCR Assay Validation, QC for CAR-T Flow Cytometry, NAb Assay Harmonization and ELISpot Validation ( Part 3 –Recommendations on Immunogenicity Assay Strategies, NAb Assays, Biosimilars and FDA/EMA Immunogenicity Guidance/Guideline, Gene & Cell Therapy and Vaccine Assays)

“…In addition, CBAs can be adversely impacted by sample pre-treatment procedures such as those aiming to improve drug tolerance. Consequently, CBAs can have poorer drug tolerance than CLBAs [61,62]. EMA and FDA immunogenicity guidelines [26,57] present the current regulatory views on NAb assay format.…”

Severe Asthma and Biologics: Managing Complex Patients

“…Several reasons of a no response to a biological treatment can be identified: i) no correct phenotype assessment at baseline; ii) clinical impact of concomitant comorbidities; iii) incomplete capacity of the biological drug to abrogate the airway process; iv) long-term history of asthma diseases with irreversible histological and functional consequences (airways remodeling; fixed airflow obstruction); v) no adherence to biological treatment (patient in home therapy); vi) development of neutralizing anti-drug antibodies (Table 1) [121][122][123][124][125]. In fact, biologicals, including mAbs, are structurally immunogenic, and the formation of antibodies [anti-drug antibodies (ADA)].…”