This followed Moderna’s earlier announcement about its two-dose vaccine being safe and producing a good immune response in young children.
The US Food and Drug Administration is considering Moderna’s application for emergency use authorization of its vaccine for this youngest age group and will also be considering Pfizer’s soon.
In the meantime, Covid-19 cases are rising across the country, driven by the very contagious subvariant of Omicron known as BA.2.12.1, according to new data from the US Centers for Disease Control and Prevention.
What should parents and caregivers know about the data thus far from Pfizer and Moderna? What is the expected timeline for when young children can get vaccinated? And what can parents and caregivers do in the meantime to reduce the risk of infection to their families?
To help answer these questions, I spoke with CNN Medical Analyst Dr. Leana Wen, an emergency physician and professor of health policy and management at the George Washington University Milken Institute School of Public Health. She is also author of “Lifelines: A Doctor’s Journey in the Fight for Public Health” and the mother of two young children.
CNN: A lot of parents have been eagerly awaiting the news of the vaccine for children under age 5. Are you optimistic based on what you’ve seen so far from the Pfizer studies?
Dr. Leana Wen: Yes, I am. To recap, Pfizer initially tested two shots of the 3-microgram dose in this youngest age group (6 months to 5 years old). This dose is one-tenth of the dose in adults (30 micrograms) and less than one-third of the dose in children 5 to 11 years old (10 micrograms).
Two shots of this lower dose were safe, the initial studies found, but they didn’t produce enough of an immune response. That’s why Pfizer started testing a three-dose version of the vaccine, since other age groups have needed at least three doses to boost protection. In fact, the FDA has authorized a third dose of the Pfizer vaccine for everyone 5 and over, and the US Centers for Disease Control and Prevention has recommended this course.
Pfizer has just announced top-line data from a study of nearly 1,700 children who received a third dose during the period when the Omicron variant was dominant. Antibody levels measured a month after the third dose were similar to the response seen in young adults 16 to 25 years old.
The company also reported that the vaccine was over 80% effective against symptomatic Covid-19 in kids 6 months to 5 years old. However, these numbers are considered to be midtrial results and not yet final.
Overall, I find these results to be promising. I’m eager to see the final trial results and to have Pfizer submit its data for regulatory review by the FDA.
CNN: How do the Pfizer results compare with Moderna’s?
Wen: It’s hard to compare them head-to-head, so let me explain what Moderna’s results showed. Moderna tested a two-dose version of its vaccine. That dosage was 25 micrograms, which is one-quarter of the dose of its adult version (100 micrograms). Researchers found that the effectiveness of the vaccine for children 6 months through 5 years old was similar to the effectiveness in older age groups: specifically, that the vaccine is 51% effective at preventing symptomatic infection in children ages 6 months to under 2 years and 37% effective at preventing symptoms in children ages 2 to 5.
Moderna’s studies also found, similar to what Pfizer announced, that its vaccine produced a robust antibody response in young children that was similar to that of older individuals. The research team also found that the vaccine was safe.
I am optimistic about these results. Moderna’s results have already been submitted to the FDA, and the agency is currently reviewing these data.
CNN: What’s the timeline at this point? When can parents expect to vaccinate their kids?
Wen: The FDA has just announced a meeting of its external advisory committee on June 15. Agency officials have said that they will discuss both Moderna’s and Pfizer’s applications for younger children on that day.
Depending on the outcome of the meetings, if advisers recommend the vaccines for authorization, the FDA could give emergency use authorization immediately after it convenes, and the CDC could meet and give its recommendation shortly after that. With this kind of schedule, it’s possible that parents could start getting their young kids vaccinated as early as the week of June 20. If both vaccines are authorized, then parents will have a choice of having their kids vaccinated with either the three-dose Pfizer vaccine or the two-dose Moderna vaccine.
CNN: Do you know yet which vaccine you’d give your children?
Wen: Either vaccine, if and when they are authorized, that’s available first. I trust the very thorough regulatory process and believe that both of these vaccines, if and when authorized by the FDA and recommended by the CDC, will be safe and effective. I am eager to give my little kids, who are ages 2 and 4, the excellent protection that everyone ages 5 and above are eligible for at this time.
CNN: With Covid-19 cases rising, what can parents do in the meantime to protect their young unvaccinated children?
Wen: Parents need to decide how important it is to them to continue avoiding the coronavirus. Some may decide that this is less important, especially if the entire family was recently infected with Covid-19. Others may decide that it’s crucial, for example, if a child is immunocompromised.
There are many methods that can help reduce risk. Outdoor gatherings are still much safer than indoor gatherings. Consider holding playdates, birthday parties and other get-togethers outdoors instead of indoors. If you are having an indoor event, consider asking everyone to do a home rapid test prior to arrival. Masking when in indoor public spaces can also reduce the chance of contracting the coronavirus.