What does full approval of Pfizer’s COVID-19 vaccine mean?

It means Pfizer’s shot for people 16 and older has now undergone the same rigorous testing and regulatory review as dozens of other long-established vaccines.

COVID-19 vaccines in the U.S. were initially rolled out under the Food and Drug Administration’s emergency use authorization, which allows the agency to speed the availability of medical products during public health emergencies.

Under the process, the FDA waived some of its normal data requirements and procedures to make the COVID-19 vaccines available months earlier than would have been possible under normal circumstances.

Pfizer’s vaccine — along with those from Moderna and Johnson & Johnson — still underwent testing in tens of thousands of people to establish safety and effectiveness against COVID-19. But the FDA initially required the companies to submit about only two months of safety monitoring data on study participants, the period when side effects are most likely to occur.

For full approval, the FDA required six months of follow-up data. FDA inspectors also visited the plants where the vaccines are made and reviewed each step of the production process for extra assurance that the shots are made under safe, sterile conditions.