The FDA and CDC say the booster isn’t currently necessary.
Pfizer and BioNTech announced that their tests on a COVID-19 vaccine booster have been going well and they intend to submit the data for approval.
According to a news release, a third dose of the current BNT162b2 vaccine given six months after the second dose has a consistent tolerability profile and elicits high neutralization titers five or 10 times higher than the primary doses. The data will be submitted in the next few weeks.
When it comes to the Delta variant, the two-dose regimen have strong neutralization titers, but the companies believe those protections would increase with a third dose. They are conducting pre-clinical and clinical tests to prove this hypothesis, according to the release.
The companies say they are also developing an updated version of the vaccine that targets the full spike protein of the Delta variant. The first batch of mRNA for a trial has already been manufactured and clinical studies are expected to begin in August with regulatory approvals, the release says.
U.S. agencies have expressed skepticism that these steps are necessary. A joint statement from the Centers for Disease Control and Prevention and the Food and Drug Administration touts the protections offered by the available two-dose regimen and urging the unvaccinated to get the shots.
“Americans who have been fully vaccinated do not need a booster shot at this time. FDA, CDC, and NIH are engaged in a science-based, rigorous process to consider whether or when a booster might be necessary,” the statement says. “This process takes into account laboratory data, clinical trial data, and cohort data – which can include data from specific pharmaceutical companies, but does not rely on those data exclusively. We continue to review any new data as it becomes available and will keep the public informed. We are prepared for booster doses if and when the science demonstrates that they are needed.”