In an update dated Thursday, the Food and Drug Administration’s change in recommendation comes even as Moderna and Novavax makers of two of the three COVID vaccines submitted their applications to the agency for updating the fall 2024 season shots with the JN.1 strain.
Novavax had said its manufacturing is underway for a JN.1 vaccine and it cannot have a shot this fall for another strain.
The company applied for authorization on Friday and said its shot showed broad cross-neutralizing antibodies against multiple variants, including KP.2 and KP.3. It said it can be ready with its JN.1 shot by mid-July.
Novavax was not immediately available for comment on the FDA’s preference for a KP.2 shot.
The FDA’s new advisory differs from the recommendations of its advisers the European regulator and the World Health Organization, all of which sought to target the JN.1 strain with the updated vaccines.
However, FDA’s Peter Marks, during the advisory panel’s meeting earlier this month, had said he wanted to give people the choice of a KP.2-targeting vaccine, counting on the quick updates possible with messenger RNA shots from Moderna and Pfizer and its partner BioNTech.
“We always say we shouldn’t be chasing strains, but we’re paying an incredibly high premium for mRNA vaccines to be able to have the freshest vaccines,” Marks, director of the FDA’s Center for Biologics Evaluation and Research, had then said.
mRNA vaccines can be developed more quickly than Novavax’s protein-based shot.
JN.1 was the dominant strain in the U.S. earlier this year. While it is no longer as prevalent, it is estimated to account for 3.1% of cases over two weeks, which ended June 8, according to the Centers for Disease Control and Prevention data.
The KP.2 variant was estimated to account for about 22.5% of cases, with KP.3 now becoming dominant at 25%.
Pfizer said on Friday that it was having discussions with global regulators, including the FDA, to assess the composition of future COVID-19 vaccine formulations. Moderna said it would be ready with the updated shot in time for the fall vaccination campaign, regardless of the final decision on the strain.
Shares of Novavax, Moderna, and BioNTech each closed more than 3.5% down in the U.S.