Pfizer and partner BioNTech have officially asked the Food and Drug Administration for emergency clearance of an omicron variant-adapted booster shot, announcing Monday they’ve completed submission of their application to the regulator.
The reformulated COVID-19 vaccine is a key part of the Biden administration’s plans for a fall vaccination campaign to help restore immunity in adults and adolescents ahead of an expected rise in cases during the winter months. In late June, the U.S. government paid Pfizer and BioNTech $3.2 billion to secure 105 million more doses of their vaccine, potentially to include the omicron-adapted version.
The two companies, along with rival Moderna, have been racing to update their COVID-19 shots and to gather sufficient evidence to prove they do a better job at fending off omicron and its sub-strains than do their original vaccines.
The research sprint has spurred debate between the companies, regulators and experts over how best to update the shots, and what level of data is needed.
Pfizer and BioNTech initially developed a “monovalent” shot based solely on the omicron variant, before pivoting to “bivalent” formulations that incorporated both the original coronavirus strain as well as omicron. The version they’re seeking FDA authorization for contains messenger RNA encoding for the original strain’s spike protein and the omicron subvariants BA.4/5.
So far, Pfizer and BioNTech only have preclinical and manufacturing data on that specific shot. But they’re also including in their application clinical safety and immune response data from a study testing an earlier version based on the BA.1 omicron strain. The latter data showed the bivalent vaccine generated levels of neutralizing antibodies against BA.1 many times greater than Pfizer and BioNTech’s currently available vaccine.
The FDA in June had recommended companies incorporate BA.4/5 strains rather than BA.1 in any updated booster shots.
Pfizer and BioNTech said that, pending authorization, their updated vaccine would be ready to ship immediately.
“It's going to be really important that people, this fall and winter, get the new shot,” White House COVID-19 response coordinator Dr. Ashish Jha said at a briefing last week.
“It's designed for the virus that's out there,” he added. “Based on everything we have seen so far, all the data suggests it should be highly effective against the new variants.”
COVID-19 cases in the U.S. have averaged above 100,000 a day for the past three months. The Centers for Disease Control and Prevention estimate that the BA.4 and BA.5 omicron variants currently account for almost all of the circulating virus, having eclipsed earlier omicron strains by mid-summer.
Pfizer and BioNTech also plan to complete an application for clearance of their shot with European regulators “in the coming days.”
In the U.K., a bivalent vaccine from Moderna was cleared for use on Aug. 15.