Lucy Nicholson | Reuters
The first study participants have already received their injections, which were developed in partnership with German drugmaker BioNTech, New York-based Pfizer announced Thursday. He intends to enroll 144 children in the first phase.
For the first phase of the trial, the company will identify the preferred dosage level for three age groups – between 6 months and 2 years, 2 and 5 years, and 5 to 11 years. Children will start with a 10 microgram dose of the vaccine before gradually moving to higher doses, Pfizer said. Participants also have the option of taking 3 microgram doses. The Covid vaccine for adults requires two injections containing 30 micrograms per dose.
The researchers will then assess the safety and effectiveness of the selected dose levels in the next phase of the trial, with participants randomly selected to receive the vaccine or a placebo, the company said. After a six-month follow-up, children who received a placebo will have the option of receiving the vaccine, he said.
Pfizer’s vaccine has previously been approved in the United States for Americans 16 years of age and older. Clinical trial studies testing the vaccine in children, whose immune systems may respond differently from adults, have yet to be completed.
Immunizing children is crucial to ending the pandemic, say public health officials and infectious disease experts. The United States is unlikely to achieve herd immunity – or when enough people in a given community have antibodies to a specific disease – until children can get vaccinated. Children make up about 20% of the U.S. population, according to government data.
At the end of January, Pfizer said it had fully enrolled its trial on the Covid-19 vaccine in children aged 12 to 15. The company said Thursday it was “encouraged” by the data from this cohort and said it hoped to share more details about the trial “soon. ”
Moderna, which also has an approved vaccine in the United States, said on March 16 that it had started testing its injection in children under 12.
Johnson & Johnson plans to test its single-injection vaccine in infants and even newborns, having first tested it in older children, according to the New York Times.
White House chief medical adviser Dr Anthony Fauci told a House committee earlier this month that the United States may start vaccinating older children against Covid-19 this fall, while that elementary-aged children could start getting vaccinated early next year.
Pfizer’s announcement comes two days after announcing the start of an early clinical trial of an experimental oral antiviral that could be used at the first sign of Covid infection.
Health experts say the world will still need a range of drugs and vaccines to end the pandemic, which has infected more than 30 million Americans and killed at least 545,282 in just over one year, according to data compiled by Johns Hopkins University.