Retrospective Cohort Study of the Effectiveness of the Sputnik V and EpiVacCorona Vaccines against the SARS-CoV-2 Delta Variant in Moscow (June–July 2021)

Abstract

The goal of this study was to evaluate the epidemiological effectiveness of the Sputnik V and EpiVacCorona vaccines against COVID-19. This work is a retrospective cohort study of COVID-19 patients. The cohort created by the Moscow Health Department included more than 300,000 infected people who sought medical care in June and July 2021. Analysis of data revealed a tendency for the increase in the Sputnik V vaccine effectiveness (VE) as the severity of the disease increased. Protection was the lowest for mild disease, and it was more pronounced for severe disease. We also observed a decrease in VE with increasing age. For the youngest group (18–50 years old), the estimated VE in preventing death in June 2021 was 95% (95% CI 64–100), and for the older group (50+ years old), it was 74% (95% CI 67–87). The estimated protection against a severe form of the disease in the 18–50-year-old group was above 81% (CI 95% 72–93), and in the 50+ years-old group, it was above 68% (CI 95% 65–82). According to our analysis, EpiVacCorona proved to be an ineffective vaccine and therefore cannot protect against COVID-19.

COVID-19 Vaccinating Russian Medical Students—Challenges and Solutions: A Cross-Sectional Study

“…In May 2021 the first component of the “Sputnik V” vaccine was registered as “Sputnik Light”, which was intended for revaccination or vaccination of young people (18–30 years old), whose immunity is well formed, and one injection is enough. Later, “EpiVacCorona” was optimized into “EpiVacCorona H”, in which two of the three peptides were combined into one [ 9 , 10 , 19 , 20 , 21 , 22 , 23 , 24 , 25 ]. In Moscow, COVID-19 vaccination began on 5 December 2020; in other Russian regions, this was on 10 December, according to the unified COVID-19 immunization program.…”

Animal Cell Lines as Expression Platforms in Viral Vaccine Production: A Post Covid-19 Perspective

“…The biggest drawback of this approach is that the synthesized peptides have low immunogenicity because they are very pure and small molecules. ,, Therefore, synthetic peptides must be used together with immunomodulators like adjuvants. In addition, since these peptides are unstable and rapidly degraded in in vivo systems due to their own structure, they require conjugation with other molecules or appropriate carrier systems. , In addition, synthetic peptide vaccines has advantages such as can be synthesized in a completely chemically defined manner, are water-soluble, maintain a stable structure under storage conditions, do not require any live expression system, , can be produced on a large scale easily, have minimal side effects (like allergy) with carrier system optimization, and when they compared with conventional systems production can be done at a very low cost. ,, EpiVacCorona synthetic peptide vaccine developed against Covid-19, which has received emergency use approval for use only in Russia and a few countries, and its effectiveness has been demonstrated by comparison with other vaccine types. , In addition, synthetic peptide vaccines are also being developed against viral agents such as influenza, HIV (human immunodeficiency virus), hepatitis B, and HPV. , …”

An overview of the vaccine platforms to combat COVID-19 with a focus on the subunit vaccines

“…B. Ryzhikov et al, 2021 ). However, based on recent analyses, EpiVacCorona has proven to be an ineffective vaccine and cannot protect against COVID-19 ( Matveeva and Ershov, 2022 ).…”