Pfizer begins trial on infants and young children

Pfizer said it has begun a clinical trial to test its Covid-19 vaccine in healthy children ages 6 months to 11 years, a crucial step in obtaining federal regulatory authorization to begin vaccinating young children and controlling the pandemic.

The first participants in the study have already obtained their features, which have been developed in collaboration with the German pharmacist BioNTech, announced on Thursday Pfizer, based in New York. It 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: 6 months to 2 years, 2 to 5, and 5 to 11 years. Children will start receiving a 10-microgram dose of the vaccine before progressively moving to higher doses, Pfizer said. Participants also have the option to take doses of 3 micrograms. The Covid vaccine for adults requires two shots containing 30 micrograms per dose.

Researchers will evaluate the safety and efficacy of selected dose levels in the next phase of the trial, and participants will be 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 opportunity to receive the vaccine.

“Pfizer has extensive experience in advancing vaccine clinical trials in children and infants and is committed to improving the health and well-being of children through carefully designed clinical trials,” the company said in a statement.

The Pfizer vaccine is already licensed for use in the U.S. to Americans over the age of 16. Clinical trial studies testing the vaccine in children, whose immune systems may respond differently than adults, still need to be completed.

Vaccination of children is crucial to ending the pandemic, public health officials and infectious disease experts say. The United States is unlikely to achieve herd immunity, or when there are enough people in a given community with antibodies to a specific disease, until children can be vaccinated. According to government data, children make up about 20% of the American population.

In late January, Pfizer said it had fully enrolled its trial of the Covid-19 vaccine in children ages 12 to 15. The company said Thursday it is “excited” by the data from this cohort and said it hopes to share additional details about the trial “soon.”

Moderna, who also has an authorized vaccine in the U.S., said March 16 she had begun testing her shot in children under 12. Moderna began a study in December to test children ages 12 to 17.

Johnson & Johnson plans to test its unique vaccine in infants and even infants, after testing it first on 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 could begin vaccinating older children against Covid-19 this fall, while elementary-aged children could start receiving shots early next year.

Pfizer’s announcement comes two days after an early-stage clinical trial of an experimental oral antiviral drug that could be used at the first sign of Covid infection began.

Health experts say the world will still need a series 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 a year, according to data collected by Johns Hopkins University.