Sputnik Light booster after Sputnik V vaccination induces robust neutralizing antibody response to B.1.1.529 (Omicron) SARS-CoV-2 variant

Abstract

COVID-19 vaccination campaign has been launched around the world. More than 8 billion vaccines doses have been administered, according to the WHO. Published studies shows that vaccination reduces the number of COVID-19 cases and dramatically reduces COVID-19-associated hospitalizations and deaths worldwide. In turn, the emergence of SARS-CoV-2 variants of concern (VOC) with mutations in the receptor-binding domain (RBD) of S glycoprotein poses risks of diminishing the effectiveness of the vaccination campaign. In November 2021, the first information appeared about a new variant of the SARS-CoV-2 virus, which was named Omicron. The Omicron variant is of concern because it contains a large number of mutations, especially in the S glycoprotein (16 mutation in RBD), which could be associated with resistance to neutralizing antibodies (NtAB) and significantly reduce the effectiveness of COVID-19 vaccines. Neutralizing antibodies are one of the important parameters characterizing the protective properties of a vaccine. We conducted a study of neutralizing antibodies in the blood serum of people vaccinated with Sputnik V, as well as those revaccinated with Sputnik Light after Sputnik V. Results showed that a decrease in the level of neutralizing antibodies was observed against SARS-CoV-2 Omicron (B.1.1.529) variant in comparison to B.1.1.1 variant. Analysis of the sera of individuals vaccinated with Sputnik V 6-12 months ago showed that there was a decrease in the level of neutralizing antibodies by 11.76 folds. While no direct comparison with other vaccines declines has been done in this study, we note their reported decline in antibody neutralization at a much more significant level of 40-84 times. At the same time, the analysis of sera of individuals who were vaccinated with Sputnik V, and then revaccinated Sputnik Light, showed that 2-3 months after revaccination the decrease in the level of neutralizing antibodies against the Omicron variant was 7.13 folds. Despite the decrease in NtAb, we showed that all revaccinated individuals had NtAb to Omicron variant. Moreover, the NtAb level to Omicron variant in revaccinated sera are slightly higher than NtAb to B.1.1.1 in vaccinated sera.

Analysis of anti-Omicron neutralizing antibody titers in different vaccinated and unvaccinated convalescent plasma sources

“…Given the urgency to assess efficacy against the upcoming VOC Omicron, most studies (with a few exceptions [21,30]) relied over Omicron pseudovirus development and neutralization assays, which, as opposed to live authentic virus, are scalable, do not require BSL-3 facilities, and provide results in less than 1 week.…”

“…This may be a false premise for recipients of inactivated whole-virus vaccines (e.g., BBIBP-CorV or VLA2001): for BBIBP-CorV, the efficacy against Omicron is largely reduced [40,41], but the impact of boost doses is still unreported at the time of writing. For CoronaVac® (SinoVac), three doses led to 5.1 fold-reduction in nAb titer [41], while for Sputnik V nAb titer moved from a 12-fold reduction at 6-12 months up to a 7-fold reduction at 2-3 months after a boost with Sputnik Light [30].…”

Single-domain antibodies efficiently neutralize SARS-CoV-2 variants of concern, including Omicron variant

“…It was shown that the virus-neutralization activity of sera samples obtained from individuals vaccinated with Pfizer/BNT162b2, Moderna/mRNA-1273 or Sputnik V decreased in the case of the B.1.351, B.1.1.28/P.1 and B.1.617.2 variants compared to wild-type virus (29)(30)(31)(32). The most pronounced decrease in the virus-neutralization activity of sera is observed in the case of the B.1.1.529 (Omicron) variant (33)(34)(35). Escape mutations are also a challenge for antibody-based therapy development.…”

Single-Domain Antibodies Efficiently Neutralize SARS-CoV-2 Variants of Concern

“…It was shown that the virus-neutralization activity of sera samples obtained from individuals vaccinated with Pfizer/BNT162b2, Moderna/mRNA-1273 or Sputnik V decreased in the case of the B.1.351, B.1.1.28/P.1 and B.1.617.2 variants compared to wild-type virus ( 30 – 33 ). The most pronounced decrease of the virus-neutralization activity of sera observed in case of the B.1.1.529 (Omicron) variant ( 34 – 36 ). Escape mutations are also a challenge for antibody-based therapy development.…”