Pfizer To Test A Third Dose Of Its COVID Vaccine On Infants, Young Children

Pfizer announced that it will begin testing a third dose of its COVID-19 vaccine in infants and young children.

The pharmaceutical company said the children between the ages of two and five did not produce a strong immune response when given two doses of its mRNA vaccine. However, children under the age of two had a similar immune response to those between 16 and 25 years old.

"Therefore, we have decided to modify each of the pediatric studies to incorporate a third dose to the series and seek licensure for a three-dose series rather than a two-dose series as originally anticipated," Kathrin Jansen, Pfizer's head of vaccine research, told investors, according to NBC News.

The third, smaller dose will be administered two months after the second shot.

Jansen said that change in the clinical trials is not expected to impact the company's plans to seek an emergency use authorization from the Food and Drug Administration during the first half of 2022.

Pfizer is also testing a third dose in children ages 5 to 11 and a third, lower dose shot in people between the ages of 12 and 17. The company said that preliminary data suggests that a third dose provides protection against the Omicron variant.