Dear Editor,
With the Pfizer-BioNTech COVID-19 pediatric vaccine being granted Emergency Use Authorization (EUA) for kids 5-11 years old by the US Food and Drug Administration (FDA) on Oct. 29, the Centres for Disease Control (CDC) signing off on this decision on Nov. 2 and, local health authorities announcing their pending decision on vaccinating children in this age group, I’ve been asked many questions by parents who require more information hence this letter is to inform.
The Approval Process for the Pediatric Vaccine:
This is no different from the process that the adult vaccine went through. The FDA granted EUA following a recommendation from the Vaccines and Related Biological Products Advisory Committee who voted (17 to 0, 1 abstention) in favour of vaccinating 5-11 year-old (a non-binding vote). Note, this is an independent committee of top experts which advises the FDA. This recommendation was based on an ongoing clinical trial with kids in this age range. From this trial the FDA notes the following on their website:
1. Effectiveness: Immune responses of children 5 through 11 years of age were comparable to those of individuals 16 through 25 years of age. In addition, the vaccine was found to be 90.7% effective in preventing COVID-19 in children 5 through 11.
2. Safety: The vaccine’s safety was studied in approximately 3,100 children age 5 through 11 who received the vaccine and no serious side effects have been detected in the ongoing study.
After the FDA’s decision, another set of leading experts advising the CDC made their recommendations (Nov 2). They voted 14 to 0 in favour of vaccinating kids 5-11 (also a non-binding decision). The CDC then endorsed this decision just hours after the recommendation was made. CDC guidance carries great weight and is usually followed by individual states and health institutions/practitioners. So, the approval process for the pediatric vaccine is no different from the adult approval process or that of any other vaccine; multiple independent expert bodies scrutinize clinical trials data available to them before making recommendations. It’s not one lone organization involved in the decision-making process.
How is the pediatric vaccine different from the adult/adolescent version?
The pediatric vaccine comes with a different label, is a lower dosage than the adult/adolescent vaccine, has different dilution requirements, has a different formulation buffer and comes in a vial with an orange cap (adult/adolescent vaccine vial – purple cap). One dose of the adult Pfizer vaccine delivers 30 ug (3/100 000 kg) of genetic material in the form of messenger ribonucleic acid (mRNA) to our cells; mRNA is the only active ingredient in the vaccine. A single dose for children (5-11) comprises 10 ug of mRNA (1/3 the adult dosage). The vaccine components/formulation are quite simple – mRNA wrapped up in lipid/fat (the lipid keeps the mRNA stable and carries it to our cells) in a buffer comprising salts and sugar (sucrose), yes regular table sugar which keeps the vaccine stable during freezing; the buffer is also for stability and to maintain pH (how acidic or alkaline something is).
This other formulation buffer (called Tris) in the kids’ vaccine keeps it more stable in the fridge for a longer period of time. We all know that one of the challenges of vaccination programs using the Pfizer vaccine is that long term storage requires super low temperatures (-70°C for 9 months). This is a particular problem in hot countries where they have to be transported for long distances to vaccination centres. Now with the kids’ version of the vaccine, the Tris buffer offers greater long-term storage at higher temperatures – they can be stored in the standard fridge (4-8 °C) for up to 10 weeks – Note, Tris buffer is a common component of many other pharmaceutical products. The decision in the US to approve this vaccine for kids took months (although millions were already vaccinated with the adult version) because a new clinical trial needed to be done for kids in the 5-11 age group; the kids vaccine had to go through the same process on its path to emergency-use authorization as the adult or any other vaccine; kids 5-11 years-old were recruited (via parents of course and this is voluntary), the trials were performed and are ongoing, the data collected and sent to regulatory authorities for scrutiny.
So far, most COVID infections in young kids have been mild however vaccinating kids not only offers them protection but helps reduce the spread in the general population since kids are part of the transmission chain even if they don’t show symptoms; they can pass it along. In addition, to get out of the pandemic we need high levels of immunity in our community which together will extend to population levels. To achieve population level immunity most people need to be immunized including children; the more aggressive Delta variant changed the threshold level (minimum amount) required for population level immunity originally estimated to be around 70-80% (now higher). In addition, there are rising infection rates in children in some parts of world like the UK. The UK recently saw infection numbers as high as 50,000 cases/day. While this is attributed to multiple reasons including the relaxation of control measures too soon such as the removal of mask mandates, high infection numbers in children and adolescents who passed on infections to the older population are thought to be a major cause by some experts. Note, to date, the UK has not approved vaccinating children under 12. On the other hand, other countries like China and Cuba (who were experiencing infection surges) have already started vaccinating young children with their own vaccines; children as young as 3 and 2 are getting vaccinated in China and Cuba respectively.
Finally, to quote Dr. Rochelle Walensky (Director of the CDC), “Data on the Pfizer-BioNTech pediatric COVID19 vaccine showed no cases of severe side effects in children ages 5-11. It is safe and over 90% effective at preventing COVID-19. Getting our younger kids vaccinated is crucial to preventing spread of the virus.”
Sincerely,
Jacquelyn Jhingree, PhD
