A booster dose of Pfizer’s COVID-19 vaccine has proven effective in children ages 5 through 11, raising a massive increase in antibodies that fight the Omicron variant, the company announced Thursday.

In addition to a significant increase in protection against the now-dominant Omicron variant, the booster — administered six months after a two-dose primary vaccine — also increases protection against the original strain, the drugmaker said.

The ongoing clinical trial has shown a 36-fold increase in protection from Omicron over an unboosted, two-dose vaccination.

The 10-microgram booster dose was tested in 140 healthy children ages 5 through 11 years.

The company said in a statement that it would be submitting its data to the US Food and Drug Administration within days.

Children between the ages of 5 and 11 have been eligible for the Pfizer shot since November of last year, meaning the first round of vaccinated children could potentially receive a booster as early as May, if authorized.

The data comes after an independent February study, conducted at the height of the New Year’s Omicron peak, showed a significant drop in protection among children who received a two-dose course.

COVID-19 infection rates among New York City’s unvaccinated residents have shown a slight uptick in recent weeks, according to health department data.