An advisory panel of U.S. experts voted on Wednesday to approve Moderna's COVID-19 vaccine for children ages 6 months to 5 years, paving the way for near approval certain in the United States, with first injections possible as early as next week.
“I know that many very relieved parents are certainly listening to us today,” commented Jay Portnoy, one of the members of this advisory committee.
After the long months of waiting to drive clinical trials, the two companies had filed an application for authorization in children from six months to 4 years old for Pfizer, and from six months to 5 years old for Moderna.
As in many countries, this is the last age group not yet to have access to this protection.
The dosage has been adapted: it represents a quarter of that of adults for Moderna (25 micrograms, compared to 100 for adults), and a tenth for Pfizer (3 micrograms, compared to 30).
Even though the youngest are less vulnerable to COVID-19, some 480 older children under the age of 4 have died from it in the United States. Hospitalization rates also increased sharply for this age group during the wave linked to the Omicron variant.
The authorization process is done in several stages. Independent experts on Wednesday reviewed all the available data, during discussions broadcast live on the internet.
During a vote, the 21 members of the committee unanimously estimated that the benefits of the vaccinating toddlers with Moderna outweighed the risks. A similar vote was expected later in the afternoon for Pfizer.
Based on these opinions, the FDA, whose decisions are a reference in the world, will then be responsible for giving its official authorization.
Some 10 million doses will then be immediately sent to the four corners of the country, ahead of millions more in the following weeks, the US government said.
Injections could begin as early as next Tuesday, once the Centers for Disease Control and Prevention (CDC) also gives the go-ahead. CDC experts will meet them this Friday and Saturday.
Pfizer in three doses
The main difference between the two products is the number of injections required : Moderna's vaccine will still be given in two doses a month apart.
That of Pfizer will be done immediately in three injections, two doses having not provoked a sufficient immune response due to the low dosage. Pfizer's first two injections will be given three weeks apart, with the third given eight weeks after the second.
Moderna representative Jacqueline Miller, however, said Wednesday that studies were also already underway. planned on the administration of a third dose. But “starting the series of injections now is vital to start protecting children this summer,” she said.
Both vaccines are safe and effective, according to the FDA, which released its own analysis of clinical trials late last week to provide a basis for discussion for experts.
According to a preliminary estimate, the vaccine from the Pfizer-BioNTech alliance was found to be 80% effective against symptomatic forms of the disease. But this figure is based on a very small number of positive cases, qualified the FDA.
Moderna's vaccine has been shown to be 51% effective in babies 6 months to less than 2 years old, and 37% in children 2 to 5 years old. These figures are consistent with the efficacy observed in adults against the Omicron variant, according to the American agency. However, the vaccine continues to protect them well against severe cases of COVID-19.
Impatience or skepticism
Regarding side effects, approximately one quarter of young children given Moderna developed fever, especially after the second dose. It usually subsided after a day.
At Pifzer, the fever rate observed was comparable between the children who received the vaccine and those who received a placebo.
While some parents are eagerly awaiting the opportunity to vaccinate their young offspring, others will no doubt be skeptical.
According to a survey by the Kaiser Family Foundation in early May, only one parent of a child of less than 5 years old in five (18%) wanted to vaccinate them as soon as possible.
Like adults, children infected with Covid-19 can suffer from long-term symptoms (Covid long). In rare cases, they may also develop severe cases of pediatric multisystem inflammatory syndrome.