The dosage of Pfizer's COVID-19 vaccine varies between age groups, with those 12 and older getting 30 micrograms and those under 12 getting 10 micrograms. But pediatricians say parents should not wait to get their child vaccinated with a larger dose if they're close to turning 12, The Wall Street Journal reported.
Paul Offit, MD, an infectious disease specialist on the FDA's vaccine advisory panel who is also the director of the Vaccine Education Center at the Children’s Hospital of Philadelphia, told the Journal Nov. 11 that a lower dose of the vaccine doesn't mean the vaccine is less effective.
The goal of any vaccine is to create a protective immune response with the lowest dose possible, as lower doses minimize side effects, the Journal reported.
Pediatric and infectious disease experts told the Journal that dosing is different for vaccines than with other types of drugs because they work in a different way. With antibiotics, for example, a patient's weight matters because a specific level of medication needs to be maintained in the bloodstream. But that doesn't apply to vaccines, which work by stimulating the immune system, the Journal reported.
In clinical trials, Pfizer tested 10-microgram, 20-microgram and 30-microgram doses of its COVID-19 vaccine in young children. The immune responses were the same for each, Stanley Perlman, MD, PhD, a pediatric infectious disease specialist who also serves on the FDA's advisory committee and is a professor of microbiology and immunology at the University of Iowa in Iowa City, told the Journal. The lowest dosage is ideal as it carries the least risk of side effects.
Pfizer said participants who got 10-microgram doses had comparable antibody responses to those ages 16 to 25 who got the larger 30 microgram doses.
The emergency use authorization for Pfizer's vaccine allows children who turn 12 between their first and second doses to get either the 10 microgram dose or the 30 microgram dose, according to the Journal. The CDC advises that children receive the dosage based on their age on the day of vaccination.
Read the Journal's full article here.