Pfizer on Monday asked the Food and Drug Administration to authorize its new Covid booster shots that target the omicron BA.5 subvariant for children ages 5 to 11.
Pfizer’s application to the FDA comes before clinical trial results of the new vaccines have been published. The company, in a statement, said its request is based on human data from a similar vaccine that targets the omicron BA.1 subvariant and data from animal studies on the BA.5 shots.
Pfizer’s main competitor on Covid shots, Moderna, asked the FDA to authorize its omicron shots for kids ages 6 through 17 on Friday. The Centers for Disease Control and Prevention cleared Pfizer’s omicron boosters for people ages 12 and older and Moderna’s new shots for adults earlier this month.
The CDC, in a document published earlier this month, said the shots will likely become available for kids as young as 5 years old in October. The health agency’s vaccine advisory committee has meetings scheduled for Oct. 19 and 20, where it is expected to review the available data on the boosters for that pediatric age group.
Officials at the FDA and CDC expect the omicron BA.5 shots will provide significantly better protection against infection and disease this fall and winter. But U.S. health officials have acknowledged that in the absence of human data, it’s unclear how much more protection the new vaccines will provide compared with the old ones.
Dr. Peter Marks, who heads the FDA’s vaccine review division, has said the U.S. is using the same process to switch the Covid vaccines to target a new strain that it uses to update flu shots every year. Flu shots are also often cleared for use without human data.
The new boosters target the dominant omicron BA.5 subvariant as well as the original strain of Covid that first emerged in Wuhan, China, in 2019. The old shots, which were developed against the original strain of Covid, are no longer providing meaningful protection against infection and mild illness because the virus has mutated so much over the course of the pandemic.
The original vaccines are still preventing severe illness, though their effectiveness against hospitalization is also declining.