Pfizer and partner BioNTech said Tuesday that they have begun testing their vaccine in children under 12 years old in a pivotal study. If the results prove positive, Pfizer said it would ask U.S. health regulators in September to expand use to some of the younger children.
In the meantime, Moderna Chief Executive Stephane Bancel said results of testing Moderna’s vaccine in children as young as five years could become available by the fall, which if positive could lead to regulatory authorization of its use in the younger age group.
The Pfizer-BioNTech vaccine is available for children as young as 12 years, while Moderna’s vaccine is authorized for use in people 18 years and older.
Moderna started a study of its vaccine in children under 12 years in March, and could have results in September or October, Mr. Bancel said at an event hosted by social-networking app Clubhouse.
Children are at lower risk of Covid-19 infection than adults, according to health experts, and when they are infected, they tend to experience milder symptoms.
Yet some can become seriously ill, and some can spread the virus. Health authorities are seeking vaccination of children to protect them and for the development of community wide, or herd, immunity that would allow for a return to a more normal life.
The companies said they have already begun enrolling children who are 5 to 11 years old in trials, and in a few weeks will begin enrolling children between 6 months and under 5 years.
Altogether, Pfizer plans to enroll up to 4,500 children at more than 90 locations in the U.S., Finland, Poland and Spain.
Pfizer expects data for children between the ages of 5 and 11 in September and, if positive, could potentially submit for an authorization later that month, a company spokesman said.
Data for children from 2 to 5 years could arrive soon after that, the spokesman said. For children between 6 months and 2 years, data could come in October or November, with an emergency use authorization to follow.