Data from Pfizer's coronavirus vaccine trials in children aged 2 years and older could be available as early as this fall, Pfizer's Senior Vice President of Vaccine Clinical Research and Development Dr. William Gruber said, possibly paving the way for use before the end of 2022.

The drugmaker is also conducting clinical trials on their vaccine for babies aged 6 months and older. Gruber anticipates data from those trials will likely be available "late at the end of the year or beginning of 2022."

Speaking on "CBS This Morning" just a day after the Food and Drug Administration granted Pfizer emergency use authorization for its COVID-19 vaccine in children aged 12 to 15, Gruber called the move a "major step" toward herd immunity in the United States. 

"This affords an opportunity to protect the adolescent against COVID-19 — although they less commonly have severe disease, they can end up in the hospital," he said. "And importantly, it allows adolescents to get back to being adolescents, to be able to to engage in sporting activities, to be able to go back to school, to be able to engage in drama club or gather in groups."

He said it presented "an opportunity to get back to normal life."

Pfizer's method for testing the vaccine on children involves gradually reducing the dosage from adults to teens to children, to find what Gruber calls "that Goldilocks spot — just right, providing the right amount of protection and being well-tolerated."

"We obviously are very attentive to being deliberate and careful, as we move down in age," he said.

In addition to kids, Americans everywhere may know whether they themselves will need another Pfizer shot before the end of 2021.

"I think we'll have some information as early the end of the summer, or early fall, in time to make decisions about the potential for offering up a booster," Gruber said.

However, he said Pfizer has data that indicates a fully-vaccinated person's current dosage could be highly effective "at least up to 6 months," and possibly more.

"It may well be the case that the vaccine provides more durable protection, and a booster might not be needed for up to a year," he said.

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