Pfizer/BioNTech report "robust" antibody response to COVID-19 vaccine in children aged 5 to 11 years with safety profile comparable to that seen in persons aged 16 to 25 years.
Pfizer and COVID-19 vaccine development partner BioNTech reported Monday positive topline results from a pivotal trial of the vaccine in children aged 5 to 11 years. The vaccine was determined to be safe and well tolerated in the youngest age group yet to receive the 2-shot series, according to a Pfizer press statement.
Results of the phase 2/3 trial showed a robust neutralizing antibody response to the 2-dose regimen of 10 µg administered 21 days apart—a dose smaller than the 30-µg given to people aged ≥12 years. The antibody responses among the younger volunteers were comparable to that seen in trials of the vaccine in those aged 16 to 25 years, according to the company. Side effects, too, were comparable to those seen in the older cohort.
“Over the past nine months, hundreds of millions of people ages 12 and older from around the world have received our COVID-19 vaccine. We are eager to extend the protection afforded by the vaccine to this younger population, subject to regulatory authorization, especially as we track the spread of the Delta variant and the substantial threat it poses to children,” said Albert Bourla, Pfizer chairman and chief executive officer, in the press statement.
“Since July, pediatric cases of COVID-19 have risen by about 240 percent in the U.S. – underscoring the public health need for vaccination. These trial results provide a strong foundation for seeking authorization of our vaccine for children 5 to 11 years-old, and we plan to submit them to the FDA and other regulators with urgency.”
This phase 2/3 study is enrolling children aged 6 months to 11 years; the current data summary was for 2,268 participants aged 5 to 11 years who received a 10-µg dose level in a 2-dose regimen. One month after the second dose was administered, immune response was strong, reflected in a SARS-CoV-2–neutralizing antibody geometric mean titer (GMT) of 1,197.6 (95% confidence interval [CI, 1106.1, 1296.6]). The finding is non-inferior to the GMT of 1146.5 (95% CI: 1045.5, 1257.2) from participants aged 16 to 25 years who served as the control group and who received a 2-dose series of 30 µg. Specific side effects in the younger children, such as fevers and chills, also were seen at a rate similar to those observed in the control group.
“We are pleased to be able to submit data to regulatory authorities for this group of school-aged children before the start of the winter season,” said Ugur Sahin, MD, PhD, CEO and co-founder of BioNTech. “The safety profile and immunogenicity data in children aged 5 to 11 years vaccinated at a lower dose are consistent with those we have observed with our vaccine in other older populations at a higher dose.”
The companies plan to share the new data with the US Food and Drug Administration (FDA) as soon as possible and are expected to include the findings in a forthcoming submission for Emergency Use Authorization. Accumulation of safety and efficacy data will continue as required to file for full FDA approval in this age group. Submission to the European Medicines Agency and other international regulators is also expected.
The Pfizer/BioNTech vaccine, called Comirnaty, is currently authorized for use in children as young as 12 in the US and many other countries. It received FDA emergency use authorization for persons aged 16 years and older in December 2020.