Novavax’s vaccine targets the JN.1 COVID-19 variant, which was the dominant strain circulating in the U.S. earlier this year but now makes up less than 1% of cases.
Both Pfizer and Moderna’s shots target the KP.2 COVID-19 variant—JN.1 is the parent variant of KP.2.
The FDA in June asked vaccine makers to create shots that target the coronavirus’ JN.1 variant, but later changed this recommendation to advise manufacturers to focus on the KP.2 strain of the JN line after reviewing updated case data; Novavax said production for JN.1-specific shots was already underway and would be able to create KP.2 shots.
The new vaccines are monovalent, which means they target one specific COVID-19 variant, though they offer some protection against other strains. KP.2 is a descendant of JN.1, and both strains are descendants of the omicron variant. Although KP.2 was the most dominant variant earlier this summer, it’s been knocked down to sixth place while its offspring currently dominate. Research has shown
all three updated vaccines are more effective at protecting against the JN lineage than the currently available XBB vaccines, which were approved last year. When compared to its XBB vaccine, Pfizer’s KP.2 COVID-19 vaccine offered up to a 7.3-times stronger response in mice infected with KP.2 and several other JN variants, according to trial data. Moderna’s KP.2 vaccine was up to eight times more effective at protecting mice against JN variants than its XBB.1.5 vaccine. Novavax scientists gave mice an XBB.1.5 vaccine and then administered the JN.1 shot 11 months after. The JN.1 vaccine was up to 48 times more effective at protecting against the JN lineage than the initial XBB.1.5 shot.
The Centers for Disease Control and Prevention recommends everyone six months and older to get an updated vaccine regardless of whether they were previously vaccinated.
Moderna and Pfizer’s vaccines will be available for people six months and older, while Novavax’s shot will be targeted toward those 12 years and older.
FDA Approves Updated Novavax COVID Vaccine Week After Approving Moderna And Pfizer’s Shots (Forbes, Aug 30, 2024)
