FDA panel picks JN.1 subvariant for fall COVID vaccines

The expert advisory panel for the Food and Drug Administration (FDA) unanimously voted Wednesday in favor of selecting the JN.1 COVID-19 subvariant to be targeted by the next round of COVID-19 vaccines this fall.

The FDA's Vaccines and Related Biological Products Advisory Committee (VRBPAC) was asked if it would recommended a monovalent vaccine that targets the JN.1 omicron subvariant for the 2024-2024 COVID vaccines. All 16 voting members voted in favor of selecting this lineage for the fall.

The JN.1 subvariant is no longer the dominant COVID-19 strain in the U.S., with the most recent surveillance data indicating it makes up less than 10 percent of cases. Current projections estimate that the KP.2 subvariant, from the family of FLiRT subvariants, is the predominant strain in the U.S.

Genomic surveillance data from the Centers for Disease Control and Prevention has not been updated in more than a week, however.

Strain selection for annual vaccines is not necessarily based on what lineage will be most dominant by the time the updates shots are deployed. The aim is to select a strain that is closely related enough to whichever strain is dominant in the country at that time that it provides strong protection.

Though the XBB subvariant lineage was chosen for the vaccines last year, the EG.5 and JN.1 subvariants rose to dominance after the vaccines were made available.

"Our current data suggest that a JN.1 or KP.2 new variant vaccine will protect against JN.1, KP.2, KP.3 and other JN.1 subvariants that are now cocirculating," a representative for Moderna said in a presentation to VRBPAC.

"From my perspective, I think it's really hard, just really hard to predict what's going to happen and where things are going to go," VRBPAC member Sarah Meyer said following the vote.
"So I do see kind of [a] reason with the thinking that JN.1 is further up on the tree. And so, if we had to guess, we had to choose, that seems to be an appropriate option."