RSV Neutralizing Antibodies in Dried Blood

Area of Science:

• Virology
• Immunology
• Clinical Trials

Background:

• Respiratory syncytial virus (RSV) neutralization is key for vaccine and monoclonal antibody (mAb) efficacy.
• Traditional serology requires venipuncture, complicating sample acquisition, processing, storage, and transport in clinical trials.
• Dried blood spot (DBS) sampling offers a simplified, cost-effective alternative.

Purpose of the Study:

• To validate an assay for measuring RSV neutralization using dried capillary blood.
• To assess the feasibility of DBS sampling as a patient-centered solution in clinical trials.

Main Methods:

• Comparison of functional antibodies in matched serum and DBS samples from a Phase 1 trial of an anti-RSV prefusion F mAb (RSM01).
• Quantification of half-maximal inhibitory concentration (IC50) using RSV-A2-mKate and Hep-2 cells.
• Evaluation of DBS sample stability over time and under temperature stress.

Main Results:

• High correlation (R2 = 0.98, P < .0001) between functional antibodies in DBS and serum.
• Assay precision for DBS was comparable to serum.
• mAb function remained stable in DBS for 9 months at room temperature and when frozen.

Conclusions:

• Feasibility demonstrated for measuring RSV neutralization via DBS.
• DBS testing presents a patient-centered alternative to serology for RSV and potentially other viral infections (influenza, SARS-CoV-2).
• This method can streamline clinical trials and reduce associated costs.