Children's Hospital Colorado

Pfizer and BioNTech COVID-19 Vaccine in Children Study

April 22, 2021
Healthy children who have not had COVID-19
5 to 11 years
COMIRB number
Reimbursement for expenses and time related to completing the e-diary

A Phase 1, Open-Label Dose-Finding Study to Evaluate Safety, Tolerability, and Immunogenicity and Phase 2/3 Placebo-Controlled, Observer-Blinded Safety, Tolerability, and Immunogenicity Study of a SARS-CoV-2 RNA Vaccine Candidate Against COVID-19 in Healthy Children <12 Years of Age

An important part of the fight against COVID-19 is developing potential vaccines to prevent this disease in children. While fewer children have been sick with COVID-19 compared to adults, children can be infected with the virus that causes COVID-19, can get sick from COVID-19, and can spread the virus to others, even if they have no symptoms (are “asymptomatic”). Although most children with COVID-19 have mild symptoms or have no symptoms at all, some children can get severely ill. 

Every modern vaccine and medicine we have today was first tested in clinical trials involving hundreds to thousands of people before becoming available to the public. Currently, there are no approved COVID-19 vaccines available for children. Before they can be approved by the United States Food and Drug Administration (FDA), COVID-19 vaccines need to be studied in a clinical trial that involves children.

Purpose of the pediatric COVID-19 vaccine study

Our team of medical experts is now conducting a clinical research study evaluating the Pfizer and BioNTech COVID-19 investigational (study) vaccine in children ages 5 to 11 years old. The purpose of this study is to learn if the vaccine can produce an immune response against COVID-19, and if it is safe, in this age group. All participants will have the opportunity to receive the COVID-19 study vaccine during their time in the trial.

Joining a clinical trial is an important and personal decision for you and your family. We hope it is one you and your child will consider.

Coronavirus vaccine study to look at vaccine safety and immune response

Who can participate

  • Children who are 5 to 11 years old
  • Children who have not been previously diagnosed with COVID-19

What to expect

  • Two-thirds (2 out of 3) of the participants will receive the COVID-19 study vaccine, and one-third (1 out of 3) will receive the placebo (injection with no active ingredient).
  • If enrolled, your child will receive 2 injections about 3 weeks apart.
  • You and your child will learn if they received the placebo approximately 6 months after the 2nd injection. If they received the placebo, participants will be given the opportunity to receive the COVID-19 vaccine.
  • Over the course of the next 2 years, your child will have between 6 and 11 planned visits as part of this research study.

Next steps

We believe developing vaccines is key to defeating this pandemic and helping to provide protection from this devastating disease. It is especially important that this trial includes children from the communities most significantly impacted by COVID-19. Involving children from all backgrounds will improve the development of this investigational vaccine for everyone. Our outreach efforts will be as inclusive as possible for these reasons.

To learn more and enroll in this vaccine study at Children’s Hospital Colorado, visit


Principal Investigator: Eric Simoes, MD, Children’s Colorado