Study include three parts. During the first part the two vaccine components will be administered separately to a small number of seronegative participants in low dose and then high dose to evaluate each component's safety. During the second part vaccine components would be administered one after another with 21 days interval to evaluate safety of the complete vaccine regimen (low dose and high dose). During the third part of the study the high dose vaccine will be administered to participants to evaluate vaccine immunogenicity. The whole study will include 200 participants. Duration of the study for each participant is about 6.5 months (no more than 194 days).
The aim of the study is to investigate the safety and immunogenicity of a two-component intranasal vaccine for the prevention of COVID-19 in healthy volunteers 18-60 years old