After the US Food and Drug Administration (FDA) fully authorized the Pfizer-BioNTech mRNA vaccine, series-completing second doses increased substantially. However, first vaccine doses were actually administered at lower rates after the approval.
When the COVID-19 vaccines were first issued Emergency Use Authorization and rolled out to Americans, public opinions diverged. Most people eagerly received at least 1 vaccine dose, excited to protect themselves and others against COVID-19; current data suggests about 70% of eligible Americans are vaccinated.
However, some people were skeptical of the vaccine and the rapidity with which it was developed. A Kaiser Family Foundation survey found that 3 in 10 unvaccinated adults said they would be more inclined to receive a COVID-19 vaccine if it received full US Food and Drug Administration (FDA) approval.
On August 23, 2021, the FDA fully approved the Pfizer-BioNTech COVID-19 vaccine. One study, published today in JAMA, sought to determine whether the full approval of the mRNA Pfizer-BioNTech vaccine increased COVID-19 vaccinations in the US.
Using the US Center for Disease Control and Prevention (CDC) COVID-19 Data Tracker, the investigators obtained daily US vaccination data. As a comparison, the investigators also examined vaccination trends in the United Kingdom. The analysis period began on July 25, 2021, 30 days prior to the full FDA approval of Pfizer-BioNTech’s vaccine, and ended on September 9, 2021, the day before the Biden Administration announced a vaccine mandate.
By analyzing daily dose-agnostic vaccinations, the investigators found that FDA approval was correlated with a cumulative increase of 3.51 million vaccinations, up by 36%. However, the full FDA approval of Pfizer-BioNTech was also associated with 16% fewer first-dose vaccinations, while series-completing vaccinations were up by 77% after the approval.
Though COVID-19 vaccinations did noticeably increase after the Pfizer-BioNTech mRNA vaccine received full FDA approval, this increase was primarily seen in series-completing second doses. The investigators postulated the approval may have actually decreased the number of first vaccine doses, when compared to expected rates without the approval.
The investigators noted that a large portion of the unvaccinated population indicated they did not trust the government, and thus FDA approval would not have swayed them to receive a COVID-19 vaccine. Another explanation of the results could be that the FDA approval reminded people who had received 1 vaccine dose that they were due for a second, and could feel confident in their decision to receive another dose.