Pfizer and BioNTech said on Wednesday that an updated analysis of the phase 3 clinical trial for their COVID-19 vaccine shows that it is 95 percent effective. They plan to file for authorization with the Food and Drug Administration “within days.”
In a press release, the companies said that there were 170 cases of COVID-19 among participants in the trial. Of those cases, 162 were recorded in people who took a placebo, and eight were recorded in people who received the vaccine. Ten cases were severe — and nine of those severe cases occurred in the placebo group. That indicates that the vaccine protects against the deadliest forms of the disease. Moderna, which released data from its trial this week, had similar findings.
Pfizer also said that the vaccine was 94 percent effective in people over the age of 65. That’s remarkable, Yale immunologist Akiko Iwasaki told The New York Times. “We know from the influenza vaccine that it’s very difficult to achieve protection in this age group with vaccines,” she said. This age group is at a high risk of severe cases of COVID-19, so protecting them is a critical goal.
The new data is an update from their announcement last week, which was based on earlier analyses of trial data and found that the vaccine was 90 percent effective. Now, Pfizer and BioNTech said they’ve collected two months of follow-up safety data, which is what the FDA asked to see before companies ask for authorization. No serious safety concerns came up in the trial. The most common side effects were fatigue and headache.
Pfizer and BioNTech said that they plan to ask the FDA for an emergency use authorization (EUA) of their vaccine, which isn’t the same as full approval. Moderna plans to ask for an EUA as well. The agency can issue these authorizations during public health emergencies like this one when there are no other approved products available for a specific disease. They can happen quickly and have a slightly lower bar than approvals. Most treatments for COVID-19 were first released under an EUA.
The FDA has to be more cautious with EUAs for vaccines than with therapeutics, Alison Bateman-House, a bioethicist and assistant professor in the department of population health at the NYU Grossman School of Medicine, told The Verge. They’re given to healthy people, not sick people. “You always have a greater burden when doing something to a healthy person versus trying to intervene on behalf of a sick person,” Bateman-House said. In October, the agency raised the bar for the amount of data it wanted companies to provide when asking for an EUA. The two-month safety follow-up was part of that guidance.
The FDA asked its vaccine advisory committee to plan on meeting on December 8th, 9th, and 10th to discuss COVID-19 vaccines, CNBC reported. That’d be an important step in the authorization process.
States are already preparing to receive doses of the vaccines and distribute them once they’re approved. Iowa health officials said they expect to get shipments of the Pfizer and BioNTech vaccine soon so that they’re ready to start vaccinating as soon as the FDA signs off. States will have their own plans, but all will start by vaccinating health care workers. Other high-risk groups, like people in nursing homes, essential workers, and people with health conditions like diabetes, would be next in line.
Vaccination for the general population could start as early as April, Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, told CNN.