The improved vaccine was developed against the Delta and Omicron COVID-19 variants. The overall design of this clinical trial was as follows: A total of 300 patients aged 18 and above who completed the basic immunization of recombinant novel coronavirus protein vaccine (CHO cell) for more than 4 months were randomly divided into the experimental group and the control group in a blind way, and were inoculated with the experimental vaccine and the control vaccine respectively. In addition, 100 patients over 4 months after the completion of basic immunization with COVID-19 mRNA vaccine were selected as the open observation group, all of whom received 1 dose of experimental vaccine. The main objective was to evaluate the immunogenicity and safety of Omicron-Delta recombinant novel coronavirus protein vaccine (CHO cells) against Omicron variants of novel coronavirus in people aged 18 years and above.
The study was designed as a randomized, blind and controlled trial. A total of 300 patients aged 18 and above who were immunized with recombinant novel coronavirus protein vaccine (CHO cell) for more than 4 months (60 patients aged 60 and above) were randomly and blind divided into the experimental group and the control group, and received the experimental vaccine and the control vaccine, respectively.~In addition, 100 patients over 4 months after the completion of basic immunization with COVID-19 mRNA vaccine were selected as the open observation group, all of whom received 1 dose of experimental vaccine.