Moderna’s Covid-19 vaccine was shown to be effective in adolescents aged 12-17 and showed no new or major safety problems in a clinical trial, the developer said on Tuesday, potentially setting the stage for a second vaccine for school-aged children to be authorized in July.
Moderna Inc, whose vaccine is authorized for adults 18 and older, said it will submit the findings of its adolescent study to the U.S. Food and Drug Administration and other regulators for emergency use authorization in early June.
U.S. regulators took about a month to review a similar study from Pfizer/BioNtech, which was authorized for ages 12-15 on May 10. If Moderna gets the same treatment, its authorization would come in early July.
Most children with Covid-19 develop only mild symptoms or no symptoms. Yet children remain at risk of becoming seriously ill, and they can spread the virus. Widely vaccinating 12- to 18-year olds could allow U.S. schools and summer camps to relax masking and social distancing measures suggested by the CDC.
“We are encouraged that mRNA-1273 was highly effective at preventing COVID-19 in adolescents,” Stéphane Bancel, Moderna’s chief executive, said in a statement.
Moderna’s trial evaluated the vaccine in 3,732 adolescents aged 12 to 17, two thirds of whom got the vaccine and one third of whom got a placebo. The main goal was to produce an immune response on par with that seen in the company’s large, Phase 3 trial in adults, which was 94.1% effective at preventing Covid-19.
Two weeks after the second dose, researchers found no cases of Covid-19 in the vaccine group compared to 4 cases in the placebo group, resulting in a vaccine efficacy of 100%, based on case definitions from the company’s adult trial.