Pfizer Inc and German partner BioNTech SE began testing their COVID-19 vaccine in children under 12, with hopes of expanding vaccination to that age range by early 2022, the US drugmaker said on Thursday.
The first volunteers in the early-stage trial were given their first injections on Wednesday, Pfizer spokesperson Sharon Castillo said.
The Pfizer/BioNTech vaccine was authorized by US regulators in late December for people age 16 and older. Nearly 66 million doses of the vaccine had been administered in the United States as of Wednesday morning, according to data from the US Centers for Disease Control and Prevention.
The pediatric trial, which will include children as young as 6 months, follows a similar one launched by Moderna Inc last week.
Frequently Asked Questions
A vaccine works by mimicking a natural infection. A vaccine not only induces immune response to protect people from any future COVID-19 infection, but also helps quickly build herd immunity to put an end to the pandemic. Herd immunity occurs when a sufficient percentage of a population becomes immune to a disease, making the spread of disease from person to person unlikely. The good news is that SARS-CoV-2 virus has been fairly stable, which increases the viability of a vaccine.
There are broadly four types of vaccine — one, a vaccine based on the whole virus (this could be either inactivated, or an attenuated [weakened] virus vaccine); two, a non-replicating viral vector vaccine that uses a benign virus as vector that carries the antigen of SARS-CoV; three, nucleic-acid vaccines that have genetic material like DNA and RNA of antigens like spike protein given to a person, helping human cells decode genetic material and produce the vaccine; and four, protein subunit vaccine wherein the recombinant proteins of SARS-COV-2 along with an adjuvant (booster) is given as a vaccine.
Vaccine development is a long, complex process. Unlike drugs that are given to people with a diseased, vaccines are given to healthy people and also vulnerable sections such as children, pregnant women and the elderly. So rigorous tests are compulsory. History says that the fastest time it took to develop a vaccine is five years, but it usually takes double or sometimes triple that time.
Only the Pfizer/BioNTech vaccine is being used in 16- and 17-year-olds in the United States. Moderna’s shot was cleared for those age 18 and older, and no COVID-19 vaccine has been authorized in younger kids yet.
Pfizer and BioNTech plan to initially test the safety of their two-shot vaccine at three different dosages – 10, 20 and 30 micrograms – in a 144-participant Phase I/II trial.
They plan to later expand to a 4,500-participant late-stage trial in which they will test the safety, tolerability and immune response generated by the vaccine, likely by measuring antibody levels in the young subjects.
Castillo said the companies hope to have data from the trial in the second half of 2021.Meanwhile, Pfizer has been testing the vaccine in children from age 12 to 15. The company expects to have data from that trial in the coming weeks, Castillo said.