Pfizer’s COVID-19 Vaccine Receives Emergency Authorization

On December 11, 2020, the FDA issued the first emergency use authorization (EUA) for a vaccine for the prevention of COVID-19 in individuals 16 years of age and older. The EUA allows the Pfizer-BioNTech COVID-19 Vaccine to be distributed in the U.S.

“Today’s action follows an open and transparent review process that included input from independent scientific and public health experts and a thorough evaluation by the agency’s career scientists to ensure this vaccine met FDA’s rigorous, scientific standards for safety, effectiveness, and manufacturing quality needed to support emergency use authorization,” said FDA Commissioner Stephen M. Hahn, MD. “The tireless work to develop a new vaccine to prevent this novel, serious, and life-threatening disease in an expedited timeframe after its emergence is a true testament to scientific innovation and public-private collaboration worldwide.”

The vaccine, which is administered as a series of two doses, 3 weeks apart, contains a small piece of the SARS-CoV-2 virus’s mRNA that instructs cells in the body to make the virus’s distinctive “spike” protein. Moderna’s COVID-19 vaccine, which is under review for emergency use authorization, also uses mRNA.

The decision follows a review of the available safety and effectiveness data from 37,586 of the participants enrolled in an ongoing randomized, placebo-controlled international study, the majority of whom are U.S. participants. Participants received either the vaccine (n=18,801) or saline placebo (n=18,785) and were followed for a median of 2 months after receiving the second dose.

The most commonly reported adverse events (AEs), which typically lasted several days, were pain at the injection site, tiredness, headache, muscle pain, chills, joint pain, and fever. These side effects appeared to occur more frequently after the second dose than the first.

Effectiveness data were available for 36,523 participants (18,198 in the vaccine group and 18,325 in the placebo group). The vaccine was 95% effective in preventing COVID-19 disease among these clinical trial participants; eight COVID-19 cases occurred in the vaccine group and 162 in the placebo group. Of these 170 COVID-19 cases, one in the vaccine group and three in the placebo group were classified as severe.

Data are not yet available to determine how long the vaccine will provide protection or if it prevents transmission of SARS-CoV-2 from person to person.

As a condition of this authorization, Pfizer and vaccination providers must report the following events to the Vaccine Adverse Event Reporting System: all vaccine administration errors, serious AEs, cases of Multisystem Inflammatory Syndrome, and cases of COVID-19 that result in hospitalization or death.

Following the authorization, Pfizer, private shipping companies, state and local health officials, the military, hospitals, and pharmacy chains coordinated efforts to deliver the first batches of the vaccine to health care workers and nursing home residents. Approximately 3 million people will receive the vaccine in the first week of distribution, including health care workers and nursing home residents. Pfizer entered a deal to supply the U.S. government with 100 million doses of the vaccine, enough for 50 million persons, by March 2021. The agreement also stipulates that the shots will be free to the public.

Sources: FDA press release, December 11, 2020; The New York Times, December 11, 2020.