The Vaccine Is Here. Now for the Hard Part.

An FDA-advisory-committee vote has marked the beginning of the end of the pandemic. But there’s still a long road ahead.

A photo of two hands filling a syringe with a vaccine
Joe Raedle / Getty

In a historic moment during the darkest days of the COVID-19 pandemic, an FDA advisory committee voted today in favor of authorizing the first vaccine against COVID-19. The formal implementation of this recommendation, which would allow the vaccine to be given to anyone 16 or older, is expected to follow imminently.

This marks the beginning of a new and hopeful phase in a crisis that has killed nearly 300,000 Americans and caused widespread economic collapse. Having endured more deaths than any other country, the U.S. has manufactured hundreds of thousands of doses in anticipation of this moment. Vaccines should be available for some Americans next week, with doses going to health-care workers and older adults at the highest risk of serious complications from COVID-19.

The vaccine is the product of a collaboration between the pharmaceutical companies Pfizer and BioNTech, which have been coordinating with regulators since development began months ago. In a video meeting today of independent experts who were tasked with evaluating the safety and efficacy of the vaccine, complete with numerous instances of accidental self-muting, the panel expressed overwhelming confidence, with some members dissenting or abstaining over the precise age cutoff.

FDA officials present offered similar support. “FDA has been conducting ongoing review of manufacturing quality, consistency, and control,” said the agency’s deputy director in the office of vaccines research and review, Doran Fink. “We have found this adequate to support emergency use authorization of the vaccine.”

The vaccine will be distributed under an emergency-use authorization, which fast-tracks drugs still under investigation because of extenuating circumstances—in this case, a pandemic that is now claiming the lives of more than 2,000 Americans each day. The agency’s criteria for such authorizations require “reasonable” evidence that the vaccine is effective, and that the “known and potential benefits … outweigh its known and potential risks.”

“Today’s vote was a significant step in bringing another weapon to the COVID fight,” Stephen Thomas, the chair of infectious diseases at the State University of New York Upstate, who also served as lead principal investigator for the clinical trial, told me. “That being said, we still have the task of bringing this vaccine to the people and earning the trust of the people so they participate in the vaccination process. Vaccines don’t save lives; vaccination saves lives.”

The new authorization does not necessarily mean that the vaccine will ultimately become approved and licensed by the FDA indefinitely. Pfizer will continue to run a phase-three randomized clinical trial with 43,448 participants to evaluate the vaccine’s safety and efficacy. So far, the results—which were published in The New England Journal of Medicine today—have shown that the vaccine is 95 percent efficacious at protecting adults. This greatly exceeded expectations; over the summer, Anthony Fauci, the leading U.S. infectious-disease doctor, said that 50 or 60 percent would be acceptable.

Because the vaccine is still technically an experimental product, the emergency authorization could be revoked if complications arise. Nancy Messonnier, the director of the CDC’s National Center for Immunization and Respiratory Diseases, told the panel that safety monitoring would be a top priority for the agency. “Information that we get will be shared quickly with the FDA and independent safety-review experts,” she said. Everyone who is vaccinated will be encouraged to download an app called V-SAFE to report their experiences after vaccination.

So far, the vaccine has shown very few serious side effects. Many people experience mild flu-like symptoms that last a day or two. In conversations with patients during the clinical trial, Thomas said, many told him the side effects would be well worth it if they led to lasting protection. It remains to be seen how long this immunity will last: Because Pfizer’s clinical trial began relatively recently, at this point it can show only that the effect lasts two months. But it is widely expected that immunity will last significantly longer. Pfizer will continue to monitor participants to see if and when the protection begins to wane.

Assuming that the vaccine remains safe and immunity lasts, today can be seen as the start of a long ending to the pandemic. Exactly how long this ending will last depends on overcoming some enormous hurdles and open questions. Jason Schwartz, who studies vaccine development at Yale School of Public Health, told me that the progress so far is “as close to a best-case scenario as we could have hoped for when vaccine research began earlier this year.” Even so, he says, “the challenges of the vaccination program that will begin in the next few days are every bit as significant as the scientific challenges that had to be overcome to develop vaccines so quickly. It’s likely to be a very bumpy road in the months ahead.”

The central goal of public-health officials in that period will be to carefully and transparently earn the public’s trust. The vaccine’s effectiveness ultimately depends on how many Americans use it, and skepticism has been widespread. In September, a poll found that 62 percent of Americans were concerned that the Trump administration was hurrying the FDA to approve a vaccine. Certain fears about politics undermining science have been justified during the pandemic, as when the FDA issued an emergency-use authorization for the drug hydroxychloroquine as a treatment for COVID-19, then subsequently revoked it because of lack of evidence. Vaccine anxieties could be assuaged gradually as doctors and nurses demonstrate their confidence by getting vaccinated, along with prominent public figures such as, ideally, Joe Biden and Donald Trump. (Trump has taken credit for the Pfizer vaccine, but it was developed outside his Operation Warp Speed program. The company opted to remain independent, with the stated goal of minimizing any potential for distrust due to politicization.)

Still, many legitimate questions do remain unanswered. One key unknown is whether the vaccine prevents infection or simply prevents symptoms of infection; in other words, it’s possible that people can still be contagious despite having been vaccinated. Other questions include any potential effect of age, pregnancy, chronic conditions, or prior infection on the vaccine’s safety and efficacy. The FDA and Pfizer will evaluate these questions on an ongoing basis, and additional studies are planned to test the vaccine in children and pregnant women.

Meanwhile, it’s unclear how Pfizer’s ongoing clinical trial—which involved giving some participants a placebo instead of the vaccine—can ethically continue once a treatment has been deemed effective. Continuing the placebo-controlled clinical trials benefits the population, but may mean creating risk for individuals involved. Already experts are grappling with whether people who received the placebo should be given the vaccine. “It’s a moral dilemma,” Steven Goodman, an epidemiology professor at Stanford University, told the panel, “a choice between two right actions.”

Ultimately, no single authorization will create public confidence; trust must consistently be earned through transparency, as well as equitable distribution of the vaccine. Nor, for that matter, will any single vaccine end the pandemic. Despite months of preparation to develop a cold chain to deliver the vaccine, Pfizer said this week that additional vaccine doses beyond the first 100 million may not be available in the U.S. until the summer. That would mean 50 million Americans—only 15 percent of the population—could be vaccinated with the Pfizer vaccine in the next six months, not nearly enough to end the pandemic.

But viewed as one tool in an arsenal to beat this virus, vaccines have the power to effectively help end the pandemic within a year. Next week, the same FDA process will evaluate—and likely authorize—a vaccine from the pharmaceutical company Moderna. The cumulative effect of these and other vaccines, in addition to the vital behavioral measures and social supports that are proven to prevent the spread of the virus, will save hundreds of thousands of lives. With enough effort and cooperation, the holidays next year could feel almost like normal. The exact timeline—and how much hardship we endure in the interim—is up to us.