The U.S. Food and Drug Administration (FDA) has recommended that COVID vaccine companies update their formulas for fall shots to target the KP.2 strain of the JN.1 variant. This decision comes after the agency’s Vaccines and Related Biological Products Advisory Committee (VRBPAC) voted to recommend a “monovalent JN.1-lineage vaccine” at a recent meeting.
As of the end of March 2024, the KP.2 variant accounted for just 4% of infections in the U.S., while over 50% of infections were attributed to its parental strain, JN.1. However, in just a few weeks, KP.2 has become the cause of around 28% of infections, with the prevalence of JN.1 variants dropping significantly.
Dr. Marc Siegel, a clinical professor of medicine at NYU Langone Medical Center, emphasized the importance of targeting the KP.2 strain due to its surge in California and its potential to spread across the country. He noted that the KP.2 strain is highly immunoevasive, meaning that immunity from previous variants may not offer adequate protection. However, getting vaccinated with the updated formula can help produce immune cells and antibodies that will provide continued protection against previous variants.
The updated vaccine is particularly crucial for high-risk groups, individuals with chronic illnesses, the elderly, and those who come in contact with them. Novavax, a vaccine maker known for protein-based vaccines, has filed an application for a JN.1 COVID vaccine that is active against current circulating strains, including KP.2 and KP.3, in line with regulatory guidance.
In response to inquiries, Pfizer and Moderna, which produce mRNA-based vaccines, have not yet commented on their plans for fall formulations. It is essential for vaccine companies to prioritize updating their formulas to address emerging variants and provide effective protection against COVID-19. Stay informed and stay safe.