Immune Response in Pfizer-BioNTech Covid Vaccines for ages 5-11 and Off-label Shots

The past two years and particularly the last couple of months have been eventful in terms of the COVID-19 vaccine. On August 23, 2021 the FDA granted full approval of the Pfizer-BioNTech vaccine, now marketed as ‘Corminaty’, for individuals 16 and up. While the full approval is for those 16 and older, individuals 12 to 15 years of age are eligible and encouraged to receive the vaccine under the FDAs Emergency Use Authorization. As of today, approximately 55% of the American population has been fully vaccinated. 

Even with these significant developments in Covid vaccines there has been a rise in cases in young children. As states relax their guidelines around COVID, schools have reopened. The rampant nature of the Delta variant has resulted in children accounting for nearly 29% of the cases reported in the United States. The AAP reported that as of September 16th, over 5.5 million children have tested positive for COVID-19 with nearly 226,000 cases during the week of September 13th. Due to the challenges the pediatric community has been facing regarding COVID vaccines, the president of the AAP, Dr Lee Savio Beers, has also expressed an urgent need for the authorization of the vaccine for younger children in the United States.  

As the need for the COVID vaccine in children has become apparent, on Monday September 20th, 2021 Pfizer announced that a Phase 2 trial showed that its COVID vaccine was safe and also generated a “robust” antibody response in children ages 5-11 years. The trial included over 2,000 participants using a two-dose regimen, 21 days apart. They used a 10 microgram dose which is one-third of the dose used for ages 12 and older. It is important to note that the trial did not measure the ability of the vaccine to prevent hospitalization or prevent COVID, instead it measured the immune response and levels of antibodies. The strong immune responses in the study population were comparable to the levels in a control group of 16-25 year olds who received a 2 dose regimen of 30 micrograms. While the Pfizer press release did not explicitly include data correlating to the extent that the immune response prevents severe disease, experts believe that the comparable antibody levels in both groups would mean similar levels of protection against the disease.

The company reported that children aged 5-11 years achieved an immune response comparable to their older counterparts in a third of the dosage. The investigation also revealed that higher doses resulted in more side effects such as headaches and fever. This has been a timely development and the FDA is under pressure to review data from the clinical trial as soon as possible. Former FDA commissioner and Pfizer Board member, Dr. Scott Gottlieb has predicted that the Pfizer vaccine for children aged 5-11 years will be made available by late October. 

In order to prepare for the onslaught of parents waiting eagerly to vaccinate their children under 12, some pediatricians have preemptively started scheduling appointments. Offices have opened up slots to accommodate vaccinations for 5-11 year olds so that they can hit the ground running the minute the FDA authorizes the vaccine. By opening up their schedules, the pediatric offices can get an estimate of how many parents in their community are ready to vaccinate their children, under 12, against Covid. This will allow them to anticipate and plan for the number of children they will be vaccinating once the Emergency Use Authorization comes through. 

The FDA is under a lot of pressure, especially by the AAP, to grant the EUA for the Pfizer vaccine in children aged 5-11 sooner rather than later, but they, along with the CDC and AAP have also strongly discouraged doctors from administering off-label vaccines to kids under 12. 

Even though vaccinations have made a significant difference in the number of hospitalizations and death, since the vaccine is authorized only for those aged 12 years and older, there has been a 10-fold increase in adolescent hospitalizations due to COVID in unvaccinated children compared to those who have been vaccinated. Additionally, Pediatric populations are severely affected in states that have low overall vaccination rates. 

Naturally, these statistics coupled with the reopening of schools and relaxed COVD guidelines are making parents anxious and eager to vaccinate their children. A US Pediatric trial site for COVID-19 vaccine, run by Dr. Bud Weiderman, currently has a 2,000 person waiting list to participate in the vaccine trial. With pressure from parents and predicted delays in authorization for younger children, some providers have been administering the vaccine to children younger than 12 years, off-label. The main concern for this is that the current authorized dose of the vaccine is much higher than the dose being tested in trials for children 11 and younger and a higher dose in younger children may cause more side effects. Another hidden drawback of administering off-label vaccines is that even though costs of administering COVID vaccine is free to all patients, insurers are not bound to reimburse providers for off-label shots. The Chair of the AAP committee on Infectious Diseases, Dr. Yvonne A. Moldonado has clearly stated that pediatricians should not be calculating doses and dosing schedules for each child below the age of 16, individually.

With the promising results of the Pfizer-BioNTech vaccine in 5-11 year olds and the urgency to authorize shown by the FDA we can anticipate a large volume of patients coming through for vaccinations by Halloween. Since the dosage requirement is different and children in that age group are more likely to get their shot at their pediatric clinic, pediatricians should expect a greater number of appointments being scheduled compared to what they saw with the authorization for ages 12 and up. To deal with this influx, Canid can help you with everything you need to hold successful vaccination clinics and to get your community vaccinated. At Canid, we have already helped pediatricians give thousands of Covid vaccines and have held multiple successful vaccination clinics. Contact us if you would like help with your COVID vaccine program.