The results of a clinical trial published in the New England Journal of Medicine show that two 10-μg doses of the BNT162b2 vaccine administered 21 days apart in children aged five to 11 years produced a robust virus-neutralising response, being 90.7 per cent effective against COVID-19.
The analysis included 48 children in phase 1 of the study who received 10 µg, 20 µg, or 30 µg of the BNT162b2 vaccine. Based on the reactogenicity and immunogenicity, the 10 µg dose was selected for further study. In the phase 2-3 trial, 2268 children were randomly assigned to receive the BNT162b2 vaccine (n=1517) or placebo (n=751).
After a median follow-up of 2.3 months, the results show that the vaccine had a favourable safety profile in the 5-to-11-year age group, similar to that described in other age groups. No vaccine-related serious adverse events were noted. One month after the second dose, the geometric mean ratio of SARS-CoV-2 titres met the immunobridging criterion in relation to values observed in the 16-to-25-year age group.
Regarding efficacy, three BNT162b2 recipients and 16 placebo recipients reported COVID-19 with onset seven days or more after the second dose, giving a vaccine efficacy of 90.7 per cent.