Strong Antibody Response With Moderna COVID-19 Vaccine in Pediatric Trial

The phase 2/3 KidCOVE study is evaluating the mRNA-1273 vaccine in healthy children aged 6 months to less than 12 years.

Robust neutralizing antibody responses were observed in a phase 2/3 study evaluating the Moderna COVID-19 vaccine, mRNA-1273, in children 6 to less than 12 years of age.

The randomized, observer-blind, placebo-controlled KidCOVE study ( Identifier: NCT04796896) is currently evaluating the effectiveness, reactogenicity, and safety of the mRNA-1273 vaccine in healthy children. The study population includes 3 cohorts: children 6 months to less than 2 years old; children 2 to less than 6 years old; and children 6 to less than 12 years old. Participants receive either two 50mcg doses of mRNA-1273 or placebo, separated by 28 days.

An interim analysis showed that the SARS-CoV-2-neutralizing antibody geometric mean ratio comparing the response in children 6 to less than 12 years of age (N=4753) to the response in young adults from the phase 3 COVE study ( Identifier: NCT04470427) was 1.5 (95% Cl, 1.3-1.8), with a seroresponse rate of 99.3%, representing a difference of 0.6% (95% CI, -2.8%, 2.8%) to the phase 3 benchmark.

As for safety, the vaccine was generally well tolerated with a safety profile consistent with that observed in the phase 3 COVE study in adolescents and adults. The most common solicited adverse events were fatigue, headache, fever, and injection site pain.

To assess continued protection and safety, all participants will be monitored for 12 months after the second dose. The study continues to enroll children 6 months to less than 6 years of age.

“We are encouraged by the immunogenicity and safety profile of mRNA-1273 in children aged 6 to under 12 years and are pleased that the study met its primary immunogenicity endpoints,” said Stéphane Bancel, CEO of Moderna. “We look forward to filing with regulators globally and remain committed to doing our part to help end the COVID-19 pandemic with a vaccine for adults and children of all ages.”


Moderna announces positive top line data from phase 2/3 study of COVID-19 vaccine in children 6 to 11 years of age. News release. Moderna Inc. Accessed October 25, 2021.