(NEXSTAR) – Pfizer’s CEO says the company is close to submitting results of COVID-19 vaccine trials among children ages 5-11 in a bid to become the first vaccine maker to gain regulatory authorization.

“I think we are going to submit this data pretty soon. It’s a question of days, not weeks,” Albert Bourla told ABC’s “This Week” on Sunday.

Earlier this month, Dr. Peter Marks, the FDA’s vaccine chief, said he was “very, very hopeful” that children in that age range could receive vaccinations against COVID-19 by the end of of the year, or sooner.

Marks said he hoped the FDA would be able to analyze Pfizer’s study results “in a matter of weeks.”

As the delta variant continues to rip through unvaccinated populations, including school-aged children, many parents, teachers and public officials are anxiously awaiting expanded access to the vaccine. Nearly all COVID-19 deaths in the U.S. now are among people who weren’t vaccinated.

With more than 40 million doses of coronavirus vaccines available, U.S. health authorities said they’re confident there will be enough for both qualified older Americans seeking booster shots and the young children for whom initial vaccines are expected to be approved in the not-too-distant future.

The spike in demand — expected following last week’s federal recommendation on booster shots — would be the first significant jump in months. More than 70 million Americans remain unvaccinated despite the enticement of lottery prizes, free food or gifts and pleas from exhausted health care workers as the average number of deaths per day climbed to more than 1,900 in recent weeks.

Federal and state health authorities said current supply and steady production of more doses can easily accommodate those seeking boosters or initial vaccination, avoiding a repeat of the frustratingly slow rollout of COVID-19 vaccines across the country early this year.

The Associated Press contributed to this report.