Pfizer’s Vaccine Hits Final Stretch for EUA With Strong Advisory Committee Backing
The FDA is very likely to grant Emergency Use Authorization (EUA) for Pfizer’s COVID-19 vaccine following a 17-4 advisory committee vote (with one abstention) Thursday in support of emergency clearance, meaning vaccinations of high-risk patients could start as soon as this weekend.
Center for Biologics Evaluation and Research Director Peter Marks cautioned that the FDA’s decision on the vaccine will come “days to weeks” after the advisory panel’s vote. Following authorization, the federal government is prepared to begin a roll-out of vaccines within 24 hours.
Committee members who voted in favor of the EUA agreed that the scientific evidence available for the vaccine showed its benefits outweighed its risks for patients 16 years of age or older. Four members — Michael Kurilla, Archana Chatterjee, A. Oveta Fuller and David Kim — voted no. Committee member Cody Meissner abstained.
While members of the committee, who are experts independent of the FDA, did not have the opportunity to explain the reasoning for their votes, concerns were expressed by Meissner and Chatterjee about a lack of data for patients aged 16 and 17.
More than 14,500 people watched the day-long advisory committee meeting, and discussions were not devoid of concerns regarding Pfizer’s vaccine, which has shown a 95 percent efficacy rate in a final analysis of its phase 3 trial and was the first to go for an EUA in the U.S.
Two patients who suffered serious allergic reactions after being vaccinated in the UK, for example, were brought up during the committee’s discussions. Paul Offit, a committee member and director of the Vaccine Education Center at the Children’s Hospital of Philadelphia, called for an additional trial to evaluate the vaccine in patients with a known history of allergies, noting the UK’s Medicines and Healthcare products Regulatory Agency (MHRA)’s current warning that patients with severe allergies should not take the vaccine.
“You’re talking about tens of millions of people who are not going to get this vaccine. This issue is not going to die until we have better data,” Offit said.
Others pointed out that more data are needed to know if the vaccine is a viable option for preventing severe COVID-19. Doran Fink, deputy clinical director of FDA’s vaccines division, countered that there are multiple examples of vaccines that protect “just as well, if not better, against severe disease as they do against mild-to-moderate disease.”
“Protection against disease of any severity is actually a pretty good predictor of protection against severe disease. We have a pretty strong result in terms of efficacy with this vaccine based on the available data, and those data that we do have for severe disease are pointing in the right direction and corroborate what history has shown us,” Fink said.
He noted that all vaccines granted emergency authorization should continue to be studied to enable a biologics license application (BLA) approval as soon as possible, including reviews of manufacturing processes, longer-term follow up and safety/effectiveness evaluations. Pfizer said that it is continuing to track trial participants for up to two years after they receive the second dose of the two-dose regimen and that it plans to file for a BLA in the new year.
Nancy Messonnier, director of the Centers for Disease Control and Prevention (CDC)’s National Center for Immunization and Respiratory Diseases, said the federal government plans to conduct active surveillance studies of the high-risk patients given any COVID vaccines.
Concerns continue to mount surrounding U.S. supplies of Pfizer’s vaccine after it became apparent this week that the Trump administration declined additional dose allotments, though the White House has strongly denied it. Currently, the government has a 100 million-dose deal with the drugmaker with an option for 500 million more shots of the vaccine, which won’t be nearly enough to vaccinate the U.S. population of 331 million (DID, Dec. 10). — James Miessler