An Open Comprative Study of the Prophylactic Efficacy and a Non-comparative Study of the Immunogenicity and Safety of the Inactivated Whole-virion Concentrated Purified Coronavirus Vaccine (CoviVac)

The study group is planned to screen a maximum of 32,000 volunteers inclusive, of which it is planned to include 3,500 men and women aged 18 to 60 years who meet the criteria for inclusion in the study and do not have non-inclusion criteria. The study group consisted of 3,500 volunteers who received the CoviVac vaccine Subgroup 1 - 2100 volunteers who will be vaccinated with the Nobivac vaccine twice with an interval of 21 days intramuscularly at a dose of 0.5 ml and revaccinated at 6 months with one dose of the KoviVac vaccine (0.5 ml). Cohorts: 1. The data of the first 1000 volunteers of subgroup 1 will be used to assess the efficacy + safety + immunogenicity of the vaccine under study. 2. The data of the next 1100 volunteers of subgroup 1 will be used to analyze the efficacy + safety of the vaccine under study. Subgroup 2 - 1400 volunteers who will be vaccinated with CoviVac vaccine three times at intervals of 21 days intramuscularly at a dose of 0.5 ml. The data of 1400 volunteers vaccinated three times with an interval of 21 days will be used to assess the effectiveness + safety + immunogenicity of the vaccine under study Control group - official data on the number of Covid-19 cases during the study period among 3,500 unvaccinated individuals. The data of the control group volunteers will be used to evaluate the effectiveness of the vaccine under study.