Is Public Pressure Impacting the FDA’s Vaccine Review Strategy?

Parents of young children are frustrated and mad.  While adults have been able to get third and even fourth COVID-19 vaccines doses for some time now, children under six years are still unable to get their shots while the rest of society reverts to a pre-pandemic normal.

Anger among parents hit a boiling point last week when White House Chief Medical Advisor Dr. Anthony Fauci confirmed reports that the Food and Drug Administration (FDA) will not approve vaccines for kids under 6 until it can simultaneously review and approve vaccines from both Pfizer and Moderna.

However, less than a week later, FDA officials seemingly changed course when they announced that they may move forward on reviewing Moderna’s vaccine without waiting for Pfizer’s application – meaning that young children could get vaccinated as soon as June.  What caused the FDA to take an about face on its vaccine review strategy?

At the time of Fauci’s comment on April 21, Moderna was poised to begin applying for an emergency use authorization (EUA) within the next week or two, as initial data showed its vaccine generated strong protection in kids.  News that the FDA could soon begin reviewing Moderna’s EUA application set off a sign of relief among parents, who have had to contend with constant delays in the race to get young kids vaccinated.

However, Pfizer’s vaccine for children under 5 is still undergoing clinical trials for a three-dose regimen after results from a two-dose regimen did not yet provide strong protection against the virus, and it’s not clear when Pfizer will be ready to submit its data.  By waiting to review vaccines from both companies, the timeline for getting shots into kids’ arms faced a decent chance of getting extended once again.

What was the FDA thinking?  According to reports,  FDA officials wanted to review vaccines from Moderna and Pfizer simultaneously because approving both at the same time would be less confusing for parents than approving each at different times.  Additionally, FDA officials were worried about a possible backlash from parents if the agency approved Moderna’s vaccine first and Pfizer’s several week later when Pfizer’s vaccine demonstrated stronger efficacy. 

Despite the FDA’s rationale, reports that federal officials were delaying the review process once again elicited a strong backlash from concerned parents and lawmakers.  In the days following Fauci’s comments, lawmakers wrote to the FDA requesting an explanation as to why vaccines for young children were being delayed again, and parents and pediatricians launched an advocacy campaign to urge the FDA to review each vaccine application “at the earliest opportunity.”

Did Public Pressure Make a Difference?

The FDA finally changed its tune on April 29, when a top official announced the agency will consider vaccine applications as soon as they are ready.  While it is not clear if the FDA shifted its strategy purely in response to political and public pressures, it wouldn’t be first time public pressure might have made a difference. 

In mid-2021, the FDA appeared to be on track to approve the vaccine for children aged 5-11 by early fall, just in time for the start of school.  However, in July, the FDA asked Pfizer and Moderna to expand the size of their clinical trials for children to make sure they could detect potentially rare side effects, namely myocarditis, or heart inflammation – effectively pushing the timeline for vaccine approval out to winter 2021 or early 2022.  This drew sharp criticism from parents and pediatricians, who argued that complications from COVID-19 posed a greater threat to kids than myocarditis.

The strongest sign of pressure on the FDA came in the form of an August 2021 letter from the American Academy of Pediatrics (AAP) that called on agency to stick to its original timeline for collecting data and authorize vaccines for children under 12 as soon as possible.  A month after the pediatricians weighed in, the FDA issued an unprecedented statement saying that it would no longer wait for additional follow-up data from expanded clinical trials to made a decision on an EUA and stick to its original timeline. 

Like many things with the pandemic, nothing is certain as the FDA determines how it will review vaccines for younger children.  Moderna only began to submit data for its EUA on April 28, and the FDA has laid out a tentative schedule that leaves open the possibility that kids under 6 could get their shots sometimes this June.  However, things could still change. An FDA official say the agency could still review EUA applications from Moderna and Pfizer simultaneously if both are filed less than a week apart, and many parents and pediatricians say June is still too long of a wait for young kids to get vaccinated, especially considering that the review process for other age groups took less time. 

However, actions undertaken by the FDA last fall and last week suggest that the agency isn’t immune to public pressure.  This sets up a precedent where advocacy could sway the FDA review process in the future – for better or for worse.

When Can Kids Under 5 Get Vaccinated?

An average 672 children per day last week were admitted to the hospital with COVID-19 last week, the highest number since the COVID-19 public health emergency began.  Surging case numbers are also causing schools to close and temporarily revert to virtual learning.  While children ages 5-17 can be vaccinated for protection against COVID-19, this currently isn’t an option for children under 5 years of age.  Even though pharmaceutical companies have been working on vaccines for younger children, some bumps in the road means the timeline for getting this cohort vaccinated hasn’t exactly been static.

Pfizer’s Swing and a Miss

Pfizer was the first COVID-19 vaccine developer to begin testing vaccine in children under five.  For its late-stage clinical trial, Pfizer administered two 3-microgram doses three weeks apart, which is less than one-third of the dose given to older children. 

Pfizer initially hoped to submit data on the efficacy of its vaccine in children in the first quarter of 2022, but an announcement from the company on December 17, 2021 signaled a delay in the timeline young children can get vaccinated.  According to Pfizer, its 3-microgram dose yielded high level of protection in children ages 6- to 24-months-old but did not generate a sufficient level of protection in children ages 2 to 5. 

Now, Pfizer is amending its clinical trial to add a third 3-microgram dose for children 6 months to 5 years of age.  If the updated trials are successful, Pfizer says it will submit data to the Food and Drug Administration (FDA) in April, which pushes the timeline for young children to get the company’s vaccine back by a few months. 

What about Moderna?

News that Pfizer is extending its trial left parents of younger kids understandably upset.  Fortunately, Pfizer is not the only company developing vaccines for children.  Moderna is currently conducting trials in children ages 6-months to 5-years-old, and the company expects to have results available by the end of January, which means the FDA could provide emergency approval as soon as late February or early March 2022.  Moderna is also testing younger children with a higher-microgram dosage than Pfizer, which presumably increases the likelihood that Moderna’s vaccine will yield an adequate immune response.

Children’s Risk Still Very Low

Even though it will probably be a few more months until younger children can get their shot, parents should feel some assurance that young children’s risk of complications from COVID-19 is extremely low.  The COVID-19 death rate for children ages 0-17 in the US is 0.1%, by far the lowest for any age group (in comparison, the death rate for US adults ages 50-64 is 1.39%). 

While pediatric hospitalizations related to COVID-19 are at a record-high, many of these hospitalizations are incidental, meaning children are being hospitalized with, but not for COVID.  An example of an incidental pediatric hospitalization could be for a child who falls on the playground, is admitted to the hospital for a broken bone, and only tests positive as a part of routine screening.

Additionally, young children who are infected with COVID-19 overwhelmingly exhibit mild symptoms or are asymptomatic, with hospital stays rare.  And while it is possible that young children can become COVID-19 long-haulers, studies are increasingly showing that long-COVID in kids is also rare

News of Pfizer’s clinical trial results was certainly disappointing for parents.  But with the possibility of better clinical trial results in the future plus strong data on the low level of risk for young children, parents should have a somewhat optimistic outlook heading into the third year of the pandemic.