On Mar. 23, 2022, Moderna announced positive interim data from the Phase 2/3 KidCOVE study of the Moderna COVID-19 vaccine (mRNA-1273) in children 6 months to under 2 years and 2 years to under 6 years of age. This interim analysis showed a robust neutralizing antibody response in both age groups after a 25 ﾵg two-dose primary series of mRNA-1273 along with a favorable safety profile.

KidCOVE was a randomized, observer-blind, placebo-controlled study to evaluate the safety, tolerability, and immunogenicity of two doses of mRNA-1273 given to healthy children 28 days apart. The study population was divided into three age groups (6 to <12 years, 2 to <6 years, and 6 months to <2 years). In the study, efficacy could be evaluated if enough cases accrued. Overall, the Company enrolled approximately 11,700 pediatric participants in the U.S. and Canada into the trial including approximately 4,200 children ages 2 to under 6 years and approximately 2,500 children ages 6 months to under 2 years.

In both age groups, the tolerability profile was generally consistent with that observed in children age 6 to under 12, in adolescents age 12 to 17, and in adults. The majority of adverse events were mild or moderate and were more frequently reported after dose two. Rates of fever greater than 38°C among vaccine recipients were consistent with other commonly used and recommended pediatric vaccines and were 17.0% and 14.6% in the 6 months to under two years and the two to under six years age groups, compared to 23.9% in the six to under 12 years age group, which received a 50 µg two-dose primary series. Fever greater than 40°C was seen in only a few children (0.2% in each age group). No study pause rules were met, and no new safety concerns were identified in either age group. No deaths, no myocarditis or pericarditis, and no multisystem inflammatory syndrome in children (MIS-C) were reported