Pfizer and BioNTech have said trial results show their COVID-19 vaccine is safe and produces a robust immune response in children aged five to 11, adding that they would seek regulatory approval shortly.
The vaccine would be administered at a lower dosage than for people aged above 12, US pharma giant Pfizer and its German partner said in a joint statement.
“In participants five to 11 years of age, the vaccine was safe, well tolerated and showed robust neutralising antibody responses,” the statement said.
It added they plan to submit their data to regulatory bodies in the European Union, the US and around the world “as soon as possible”.
The trial results are the first of their kind for children below 12 for widely used vaccines, with a Moderna trial for six- to 11-year-olds still ongoing.
Last week, Cuba announced that it had begun vaccinating children as young as two with its homegrown vaccines, which its health officials said had been found to be safe for younger people.
Both the Pfizer and Moderna vaccines are already being administered to adolescents above 12 and adults in countries around the globe.
The update comes as countries continue to grapple with the highly contagious Delta variant and vaccine hesitancy in some adults, which continue to prolong the pandemic. It also comes as health authorities weigh whether booster shots of the available vaccines are needed for adults.
Although children are considered less at risk of severe COVID-19, there are concerns that the Delta variant could lead to more serious cases.
Inoculating children is also seen as fundamental to keeping schools open and helping end the pandemic.
“We are eager to extend the protection afforded by the vaccine to this younger population,” said Pfizer CEO Albert Bourla, noting that “since July, paediatric cases of COVID-19 have risen by about 240 percent in the US”.
Kids in the five to 11 age trial group received a two-dose regimen of 10 microgrammes in the trial, compared with 30mg for older age groups, the companies said. The shots were given 21 days apart.
The 10mg dose was “carefully selected as the preferred dose for safety, tolerability and immunogenicity” for that age group, the statement said.
The side effects were “generally comparable to those observed in participants 16 to 25 years of age”, it added.
Among the most commonly reported side effects in the past have been pain and swelling at the injection site as well as headache, chills and fever.
Israel has already given special authorisation to vaccinate children aged five to 11 who are “at significant risk of serious illness or death” from COVID-19, using the Pfizer jab at the lower dosage.
Pfizer and BioNTech are also trialling their vaccine on infants aged six months to two years, and on children aged two to five.
The main results for those trials are expected “as soon as” the fourth quarter of this year, the companies said.
Altogether, up to 4,500 children aged six months to 11 years have enrolled in the Pfizer-BioNTech trials in the US, Finland, Poland and Spain.
Like its Moderna rival, the Pfizer jab is based on mRNA technology that delivers genetic instructions to cells to build the coronavirus spike protein to evoke antibodies when bodies encounter the real virus.