On December 11, Pfizer-BioNTech’s COVID-19 vaccine was granted Emergency Use Authorization (EUA) by the US Food and Drug Administration (FDA). This is the first COVID-19 vaccine to be granted an EUA in the United States. A vaccine by Moderna is also awaiting EUA. At present the EUA has been granted to offer the vaccine to individuals who are aged 16 years or more.

FDA Commissioner Stephen M. Hahn, M.D., said, “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.” He added, “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.”  

In a statement released, the FDA explained, “The Pfizer-BioNTech COVID-19 Vaccine contains messenger RNA (mRNA), which is genetic material. The vaccine 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. When a person receives this vaccine, their body produces copies of the spike protein, which does not cause disease, but triggers the immune system to learn to react defensively, producing an immune response against SARS-CoV-2.”

Peter Marks, M.D., Ph.D., Director of the FDA’s Center for Biologics Evaluation and Research, allayed fears about the vaccine’s efficacy saying, “With science guiding our decision-making, the available safety and effectiveness data support the authorization of the Pfizer-BioNTech COVID-19 Vaccine because the vaccine’s known and potential benefits clearly outweigh its known and potential risks. The data provided by the sponsor have met the FDA’s expectations as conveyed in our June and October guidance documents.” He reiterated, “Efforts to speed vaccine development have not sacrificed scientific standards or the integrity of our vaccine evaluation process.”

Process of Evaluation and Available Data on Safety and Efficacy

The FDA explained, “Pfizer BioNTech COVID-19 Vaccine is administered as a series of two doses, three weeks apart. The available safety data to support the EUA include 37,586 of the participants enrolled in an ongoing randomized, placebo-controlled international study, the majority of whom are U.S. participants. These participants, 18,801 of whom received the vaccine and 18,785 of whom received saline placebo, were followed for a median of two months after receiving the second dose.”

On the subject of side effects, the FDA said, “The most commonly reported side effects, which typically lasted several days, were pain at the injection site, tiredness, headache, muscle pain, chills, joint pain, and fever. Of note, more people experienced these side effects after the second dose than after the first dose, so it is important for vaccination providers and recipients to expect that there may be some side effects after either dose, but even more so after the second dose.”

With respect to efficacy of the vaccine, the FDA said, “The effectiveness data to support the EUA include an analysis of 36,523 participants in the ongoing randomized, placebo-controlled international study, the majority of whom are U.S. participants, who did not have evidence of SARS-CoV-2 infection through seven days after the second dose. Among these participants, 18,198 received the vaccine and 18,325 received placebo. The vaccine was 95% effective in preventing COVID-19 disease among these clinical trial participants with eight COVID-19 cases in the vaccine group and 162 in the placebo group.”

*Feature image: U.S. Air Force photo by Senior Airman Areca T. via Wikimedia Commons.