By Chris Adams
Aug. 13, 2020 – The U.S. Food and Drug Administration has been “roundly roasted” from two sides as it tries to negotiate the treacherous landscape of expediting a coronavirus vaccine through development while also maintaining rigorous safety standards, according to the official overseeing the process, Dr. Peter Marks, director of the FDA’s vaccines division.
Marks explained to National Press Foundation fellows how the agency decided on its approval thresholds, which declare a coronavirus vaccine should be 50% effective.
That means that during phase 3 safety and efficacy trials in which some people get the vaccine and others get a placebo, the vaccine needs to be 50% better than the placebo in preventing or lessening COVID-19, the disease caused by the virus formally know as SARS-CoV-2.
“That has been roundly roasted from both sides – some people saying, ‘Well, wouldn’t you accept a vaccine that has lower efficacy in some patients, because … it could at least help some people?’” said Marks. “And on the other hand, some people said, ‘Well, wait a second – 50%, do you really mean that? That probably wouldn’t give you herd immunity, even if you vaccinated 90% of the population.’”
Marks said the 50% standard was “a reasonable place to come out,” given that the annual flu vaccine in a good year is only 50% effective.
“It’s not perfect, but it’s something to start with,” he said. “I think what it also does is it puts a basement on things.” (The FDA’s full guidance is here.)
Marks is director of the Center for Biologics Evaluation and Research, one of six FDA centers. In normal years, the center’s oversight of vaccines, blood and other biological products is out of the public spotlight. Vaccines rarely create the kind of news generated by blockbuster pharmaceutical drugs overseen by a different center.
Not this year. Approval of a coronavirus vaccine will be among the most consequential actions in FDA history. The FDA – and Marks – will need to defend decisions that will sometimes differ from those of competing regulators in Europe or other nations. As of August 13, there were 29 candidate vaccines in clinical trials around the world, according to the World Health Organization. (A list of vaccine tracking sites is here.)
The decision comes as researchers experiment with multiple approaches to design a vaccine. Some – such as DNA and RNA vaccines – have never before been approved for human use.
Also weighing on Marks is the reality that Americans will be wary of whatever vaccine is developed and approved. In polls (ABC News/Washington Post, Pew Research Center), roughly a quarter of Americans said they were unlikely to get a coronavirus vaccine.
“We need to make sure that we do our best to take anyone who might be on the fence about taking a vaccine and helping them over that fence,” Marks said. “I don't know whether we’ll be able to get the people that are really, really clinging to not believe in that vaccines work. But we need to try to get as many people on board with the vaccine.”
Fellows also heard from Dr. José Romero, the interim health commissioner for the state of Arkansas who is also chairman of the U.S. Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices.
That committee creates the vaccine schedules that government programs and insurers rely on. While the FDA approves vaccines for release to the marketplace, the CDC committee plays a big role in green-lighting their widespread adoption. Once the committee’s recommendations are accepted and published, the federal Vaccines for Children program must pay for the vaccine.
Romero said the committee has been accelerating its assessments of coronavirus vaccines in the pipeline. The committee is made up of academic and government experts, including representatives from important medical associations such as the American Academy of Pediatrics. Its meetings are broadcast online.
Dr. José R. Romero
Dr. Peter Marks