The Food and Drug Administration on Monday granted full approval to Pfizer and BioNTech's coronavirus vaccine, a long-awaited decision that government officials hope could help convince people who have so far waited or refused to get their shot.
The approval, a landmark in the public health response to the pandemic, could also clear the way for more employers and institutions to impose vaccine mandates as a wave of COVID-19 cases driven by the delta variant forces many states to pause or roll back steps toward a reopening.
The FDA's approval of the companies' application comes 108 days after they formally submitted to the agency and an incredible 16 months after the vaccine was first given to a volunteer in a clinical trial, a historic sprint that gave the world a safe and highly effective vaccine.
The decision by the agency converts the emergency authorization FDA officials signed on Dec. 11. Since then, more than half of the U.S. population — nearly 171 million people — have been vaccinated with Pfizer and BioNTech's vaccine and the two others that followed from Moderna and Johnson & Johnson.
In recent months, however, vaccinations have slowed amid persistent hesitancy of the vaccines and lingering skepticism among some of the threat posed by COVID-19 to healthy adults. Scientists and public health officials believe at least 70% to 80% of the population will need to be vaccinated in order to achieve some level of herd immunity sufficient to curb the pandemic. According to data tracked by Bloomberg, it will take another four months to reach those levels at current vaccination rates.
“We know the vaccine approval holds the promise of altering the course of the pandemic in the United States," acting FDA Commissioner Janet Woodcock said in a call with reporters. "And of course for some an FDA-approved COVID vaccine may instill in them the confidence to go and get vaccinated."
The FDA's approval of the vaccine, which will be marketed under the name Comirnaty, was based on a longer follow-up of patients and further analysis of safety and efficacy data since the Dec. 11 authorization. When Pfizer and BioNTech asked the FDA for the authorization last year, the companies relied on results from a clinical trial of 44,000 volunteers that showed an efficacy against symptomatic COVID-19 of 95%, as well as two months' worth of side effect reporting following participants' second dose.
Their application for full approval, by comparison, included side effect data through at least six months from 12,000 trial participants. The FDA reaffirmed the vaccine's safety, although the agency called attention in its announcement to the recently identified risk of inflammation of heart muscles and tissues surrounding the heart. According to the agency, the risk is greater in men under age 40 and highest in men aged 12-17. Symptoms go away for most, although the FDA cautioned that some individuals have required intensive care support. "Information is not yet available about potential long-term health outcomes," the agency said.
Data released in July also showed efficacy remained high, at about 91%, through six months, although those results were from before the more infectious delta variant was widely prevalent in the U.S. The vaccine makers expected early on that efficacy would fall as the immune response decline over time and recipients are exposed to more infected people. Still, that level of protection is greater than what's reported for many commonly used vaccines like those for seasonal influenza.
As a fully FDA approved product, Pfizer and BioNTech's vaccine may now be more attractive to some of the people who were waiting until this decision before rolling up their sleeves. A recent poll from the Kaiser Family Foundation found that 31% of unvaccinated people would be more likely to get their shots based on approval, although that same survey suggested some misunderstanding about the vaccines' approval status.
Likewise, some employers were unwilling to mandate that their workers get immunized until the FDA issued the approval. A survey conducted by the law firm Fisher Phillips found that 10% of employers that had not required vaccination of their employees were waiting until the FDA had issued an approval.
The approval comes as the delta variant propels a new wave of disease across the country — particularly in places that have low vaccination rates or have lifted mask mandates and forbidden local governments from re-instituting them.
The surge in cases was one factor that led U.S. health officials to call for all Americans to receive a booster shot eight months after their original two-dose regimen, beginning in late September. The FDA has not yet authorized an additional dose for broad use, although the agency did grant authorization of a booster for people who have received an organ transplant or whose immune systems are similarly weakened.
Meanwhile, the FDA will likely be asked soon whether to authorize Pfizer and BioNTech's vaccine in children younger than 12. Anticipation for that potential clearance has grown considerably as infections and hospitalizations from COVID-19 have reportedly hit record highs this month.
But senior officials on Monday warned against "off-label" use now that the vaccine has full approval, saying trials are still underway. The doses tested in adults and children are different, and the agency recently asked Pfizer and Moderna to expand the size of those studies to better detect the prevalence of a rare, heart-related side effect that’s been observed in younger vaccine recipients.
"That would be a great concern, that people would vaccinate children," Woodcock said, arguing the agency doesn't yet have the "proper dose," or safety and efficacy data to support use in kids under 12.
In addition, the agency will eventually need to make decisions on whether to grant similar approvals to vaccines from Moderna and J&J. Moderna began its application process on June 1, less than a month after Pfizer, while J&J has not yet applied.