Efficacy of Two Vaccine Platforms against SARS-CoV-2

Several vaccine platforms have been designed to elicit an effective immune response against SARS-CoV-2. This study was aimed to evaluate the humoral immune response in Iranian people vaccinated with both inactivated virus vaccines and vector vaccine platforms.

The study enrolled 360 vaccinated individuals with inactivated virus vaccines (BBIBP-CorV and Covaxin) and vector vaccine platforms (AstraZeneca and Sputnik V). Serum samples were collected for each volunteer on days 14 to 21 after vaccination, and anti–SARS-CoV-2 spike receptor-binding domain (RBD) IgG concentrations were analyzed by ELISA.

Higher antibody titers were observed in participants vaccinated with vector vaccines compared with those immunized with inactivated virus, especially in subjects who received two doses of AstraZeneca. (AstraZeneca: 204.19 U/mL [95% CI, 175.5-232.2] vs. Sputnik V :114.67 U/mL [95% CI, 99.54-129.8]; P = 0.007). It was also observed that antibody titers were not significantly different between the two groups receiving inactivated vaccines (P = 0.86). Our results indicated that 28% of the population vaccinated with Covaxin and 32% of people vaccinated with BBIBP-CorV showed no response to the vaccine. There was also a statistically insignificant difference between age, BMI, and gender with antibody level in each group of vaccines (P > 0.05).

Based on a limited population data , our study showed that the viral vector-based vaccines produced higher levels of neutralized antibodies than the inactivated vaccines, and their rate of non-response was lesser.