CDC advisers voted Saturday to recommend Covid vaccines for the youngest children Source: Ron Harris/Associated Press
Scientific advisers from the Centers for Disease Control and Prevention began a meeting Saturday to decide whether the benefits of Covid vaccines outweigh the risks for children under the age of 5, one of the last groups of Americans to campaign for the shots have qualified.
The meeting, which will be streamed live here, began at 10 a.m. Eastern Time. Advisors are expected to vote yes, despite reservations over the lack of data, particularly regarding the efficacy of Pfizer-BioNTech’s vaccine.
Earlier this week, another panel of experts advising the Food and Drug Administration unanimously backed the vaccines. The FDA on Friday approved the Moderna vaccine for children ages 6 months to 5 years and the Pfizer vaccine for children ages 6 months to 4 years. (Pfizer-BioNTech’s vaccine has been available for children ages 5 and older since November.)
On Friday, CDC advisers heard evidence of the vaccines’ effectiveness in the youngest children. But the committee repeatedly pressed Pfizer for its estimates, noting that three doses of that vaccine would be needed to protect children, compared to two doses of the Moderna vaccine.
Both vaccines are safe and both produced levels of antibodies similar to those found in young adults. When the committee’s approval was quickly given the green light by the agency’s director, Dr. Rochelle Walensky, follows, States are preparing to start vaccinating children next week.
Among the challenges facing the CDC panel Saturday is the difficulty of recommending two very different vaccines for the same population.
“Executing these two rollouts will be incredibly challenging,” said Katelyn Jetelina, a public health expert and author of the widely read newsletter Your Local Epidemiologist.
“There’s going to have to be a lot of proactive communication about the difference between the two and the implications of emphasizing one over the other,” she said.
In its clinical trials, Moderna found that two injections of its vaccine, each at a quarter of the adult dose, produced antibody levels at least as high as those seen in young adults.
The company estimated the vaccine’s effectiveness against symptomatic infections at about 51 percent in children aged 6 to 24 months and 37 percent in children aged 2 to 5 years. Side effects were few, although about one in five children had a fever.
Based on this data, the FDA approved two doses of the Moderna vaccine four weeks apart.
The Pfizer-BioNTech vaccine also generated a strong immune response, but only after three doses, company officials told scientific advisers on Friday.
Two doses of the vaccine were insufficient, they said, justifying the FDA’s decision in February to delay approval of the vaccine until regulators had data on three doses. Two doses may not have been enough, as the company only gave children a tenth of the adult dose with each injection, some advisers said.
The vaccine has an overall effectiveness of 80 percent in children under the age of 5, Pfizer scientists claimed on Friday. However, that calculation was based on only three children in the vaccination group and seven receiving a placebo, making it an unreliable metric, CDC consultants noted.
“We should just assume that we don’t have efficacy data,” said Dr. Sarah Long, an infectious disease expert at Drexel University College of Medicine. But dr Long said she was “comfortable enough” with other data showing the vaccine’s effectiveness.
Three doses of the Pfizer vaccine produced antibody levels comparable to those seen in young adults, suggesting it’s probably just as effective.
“The Pfizer is a three-dose series, but as a three-dose series it’s quite effective,” said Dr. William Towner, who led vaccine trials for Moderna and Pfizer at Kaiser Permanente in Southern California.
Any vaccine would be better than none, added Dr. Towner added. He predicted that some parents might choose Moderna because it’s easier to take kids to a pediatrician for two shots than making sure they get three doses.
The Pfizer vaccine was approved in November for children ages 5 to 11, but less than 30 percent in that age group have received two shots. Parents of the youngest children may be more willing to choose a Covid vaccine if it can be offered alongside other routine vaccinations, said Dr. towner
“That’s the area that a lot of people are unsure about right now,” he said. “I hope there will be a guide to that.”