The FDA is directing Covid-19 vaccine manufacturers to update their formulations to target the KP.2 strain of the virus, citing higher circulation levels of that strain in recent weeks.
Last week, the agency’s Vaccines and Related Biological Products Advisory Committee recommended that manufacturers produce monovalent vaccines targeting the JN.1 strain of the virus. But based on disease activity in the US, the agency said Thursday that it determined that the strain instead should be KP.2.
“FDA has communicated this change to the manufacturers of the licensed and authorized Covid-19 vaccines,” the FDA said. “The agency does not anticipate that a change to KP.2 will delay the availability of the vaccines.”
KP.2 and KP.3 have become the dominant strains of Covid-19 in the US, accounting for 22.5% and 25% of cases as of the past week, according to CDC data.
A Pfizer spokesperson told Endpoints News that it’s having ongoing discussions with the FDA and global regulators about the composition of future Covid-19 vaccine formulations.
“We will continue to evaluate the data and will share further updates in due course,” the spokesperson said.
Novavax announced Friday that it submitted its updated vaccine targeting the JN.1 lineage, which it says is active against multiple strains, including KP.2 and KP.3. The company said it will have doses for distribution by mid-July.
John Jacobs“Novavax is committed to having a protein-based Covid-19 option available at the start of the vaccination season, which is critical because research suggests that providing vaccine choice, along with healthcare provider recommendations, may help improve vaccination rates,” Novavax CEO John Jacobs said in a statement.
Moderna said in an emailed statement Friday that it plans to produce vaccines “in accordance with the latest regulatory guidance and strain recommendations from the FDA” in time for the fall vaccination season.
At last week’s VRBPAC meeting, committee members were concerned that Novavax, which manufactures protein-based vaccines, wouldn’t be able to produce a KP.2 vaccine in time for the fall season and thus were swayed toward choosing JN.1 to ensure a protein vaccine would be available. But FDA biologics center director Peter Marks pushed back during discussion, making his case to go with KP.2.
“I’m just a little concerned that perhaps the committee doesn’t understand that if they choose to recommend or to make any comments about a KP.2 vaccine that does not mean that … there will not be availability of a JN.1 Novavax vaccine,” Marks told the committee. “It just may mean that there will be two different formulations available.”
Next up, the CDC’s Advisory Committee on Immunization Practices is set to make a determination this summer about who should receive the updated vaccines. The CDC director will have to sign off on that decision before the vaccines can be rolled out in the fall.