Temporal Increase in Neutralization Potency and Reduced Escape of Viral Variants to SARS-CoV-2 Antibodies after Sputnik V Vaccination

Recent studies have shown temporal increase of neutralizing antibody potency and breadth to SARS-CoV-2 variants in convalescent individuals. Here, we found a similar process after Sputnik V vaccination. We examined longitudinal antibody responses and viral neutralizing capacity to variants of concern (VOC: Alpha, Beta, Gamma and Delta) and a broadly spread variant of interest (VOI: Lambda) in volunteers up to 6 months of receiving Sputnik V vaccine in Argentina. A collection of 1800 serum samples obtained between January and August 2021 were used. The analysis indicates that while anti-spike IgG levels significantly wane over time, neutralizing potency against the original SARS-CoV-2 and VOC increase within four months of vaccination, suggesting antibody maturation. This increase was more evident for Beta and Gamma variants, which showed the highest ability for neutralization escape. Our observations suggest that protection increases over time after Sputnik V vaccination as a consequence of antibody maturation, resulting in improved potency of antibodies to viral escape mutations.