WASHINGTON (AFP) - Pfizer's Covid-19 vaccine is more than 90 per cent effective in preventing symptomatic forms of the disease in children aged five to 11, the company said in a document released on Friday (Oct 22).
The new data was published on the website of the Food and Drug Administration, which has called an advisory panel of independent experts to meet next Tuesday to decide whether to authorise the vaccine in this age group.
The analysis was based on around 2,250 trial participants, with data accruing until Oct 8, and most positive cases occurred when the Delta variant was dominant in the United States and globally.
"VE (Vaccine efficacy) against laboratory-confirmed symptomatic Covid-19 occurring at least seven days after dose two in evaluable participants without evidence of prior Sars-CoV-2 infection was 90.7 per cent," the document said.
There were no cases of severe Covid-19 and no cases of multisystem inflammatory syndrome in children (MIS-C), a rare but serious post-viral condition.
There were no cases of myocarditis or pericarditis (heart inflammation or inflammation around the heart) - but there were not enough study volunteers to be able to detect highly rare side effects, and male adolescents are thought to be a higher risk group.
This is the first time Pfizer has released an efficacy estimate for its Covid-19 vaccine in younger children.
Its earlier press statement said only that the shot produced a robust immune response. The vaccine was tested with a 10 microgram dose, while older age groups have received 30 micrograms.
The administration of President Joe Biden has said it stands ready to roll out shots for the country's 28 million five- to 11-year-olds as soon as the vaccine is authorised by science agencies.