51˶

FDA Approves Pfizer's COVID Vaccine

— "Milestone" in pandemic, acting FDA commissioner says

Last Updated August 24, 2021
MedpageToday
FDA Approves Pfizer's COVID Vaccine

The FDA , the first vaccine against the novel coronavirus to receive full approval.

The vaccine will be marketed as Comirnaty, and can be used for individuals ages 16 and older to prevent COVID-19. However, the vaccine is still under emergency use authorization (EUA) for adolescents ages 12-15, the agency said.

FDA Acting Commissioner, Janet Woodcock, MD, characterized the approval as a "milestone" in the pandemic.

"While this and other vaccines have met the FDA's rigorous, scientific standards for emergency use authorization, as the first FDA-approved COVID-19 vaccine, the public can be very confident that this vaccine meets the high standards for safety, effectiveness, and manufacturing quality the FDA requires of an approved product," she said in a statement.

At a media briefing, Peter Marks, MD, PhD, the director for the Center for Biologics Evaluation and Research at FDA, detailed the meticulous process used for conducting a review of a biologics license application for full approval. The agency inspected data down to the patient level, reviewing "tens of thousands" of patient data on adverse events, and even did their own analysis, and in record time, Marks added.

"It's been 97 days since Pfizer completed their role" and the FDA completed the process in "40% of the normal clock time for a submission of this magnitude," he said.

The vaccine has been under an EUA since Dec. 11, 2020 for individuals ages 16 and older. Evidence for the full approval comes from expanded phase III trial safety and efficacy data released by the manufacturer this April. An analysis of 927 confirmed cases in the trial of approximately 44,000 individuals -- who were randomized 1:1 to vaccine or placebo -- found that starting a week after the second dose, Comirnaty had a 91.3% efficacy against symptomatic COVID-19 through 6 months.

More than half of the participants had over 4 months of safety data, including 12,000 people who were followed up through 6 months. Injection site pain, fatigue, headache, muscle or joint pain, and fever were the most common adverse events. While the FDA noted an increased risk of myocarditis and pericarditis in the 7 days following the second dose, particularly among males younger than age 40 (with the highest risks among males ages 12-17), short-term follow-up data suggest most symptoms resolved completely.

The FDA noted that they are requiring Pfizer to conduct a post-marketing study about the risks of post-vaccination myocarditis and pericarditis, which will include following long-term outcomes of those with these conditions following vaccination with Comirnaty.

In addition, the FDA added that Pfizer will conduct additional post-marketing studies not required by the agency, including a pregnancy registry study in order to track post-vaccination pregnancy and infant outcomes.

Data from the trial was collected prior to the Delta variant becoming the dominant strain in the U.S. Marks noted, however, that "real-world data" from Israel suggest the vaccine is still effective, but that effectiveness wanes with time. He said the agency is following this closely, leading to consideration of boosters "as we move into the fall."

Naturally, with full approval, reporters asked about off-label use of the vaccine, specifically in pediatric patients younger than age 12, as well as booster doses for a population where they are not yet indicated.

During the briefing, Woodcock strongly discouraged off-label use of the vaccine, noting that it is available under a provider agreement with the U.S. government through the CDC.

"There would be many considerations that would pertain to off-label prescribing for the recipient," she said.

Woodcock said that Monday's announcement should give those who delayed getting vaccinated until full FDA approval "the confidence to go get vaccinated."

Marks even took a moment to refute some of the "overwhelming amount" of misinformation circulating about COVID-19 vaccines, including claims about infertility, microchips, and that the vaccines have caused thousands of deaths.

"Let me be clear: these claims are simply not true. Getting a COVID-19 vaccine can save your life," he said.

  • author['full_name']

    Molly Walker is deputy managing editor and covers infectious diseases for 51˶. She is a 2020 J2 Achievement Award winner for her COVID-19 coverage.