The Food and Drug Administration (FDA) has officially approved the latest COVID-19 vaccines from Pfizer and Moderna for the upcoming fall 2024 season. This approval, announced on Thursday, sets the stage for an earlier-than-usual distribution of the updated vaccines.
This year’s versions of the Pfizer and Moderna vaccines have been specifically updated to target the KP.2 variant of SARS-CoV-2, the virus responsible for COVID-19. This revision is part of an annual effort by the FDA and global health authorities to ensure vaccines are adapted to combat the most recent and prevalent strains of the virus.
“With immunity waning due to previous virus exposure and past vaccinations, we strongly encourage eligible individuals to consider receiving the updated COVID-19 vaccine to enhance protection against current variants,” stated Dr. Peter Marks, Director of the FDA’s Center for Biologics Evaluation and Research.
The Centers for Disease Control and Prevention (CDC) is recommending that all Americans aged six months and older receive the “updated 2024-2025 COVID-19 vaccine” to mitigate another anticipated surge of the virus this fall and winter. CDC Director Dr. Mandy Cohen, in a recent presentation to the American Medical Association, emphasized the importance of starting the vaccination process as soon as the vaccines are available, suggesting that administration should continue through the months of September, October, and November.
Both Pfizer and Moderna have announced that their updated vaccines will be available nationwide in the coming days. Additionally, Novavax is expected to receive FDA authorization for its updated vaccine later this year.
Accelerated Rollout of Updated Vaccines
Health authorities have worked to expedite the rollout of this year’s COVID-19 vaccines, learning from the challenges of last year’s late-September release, which led to confusion and accessibility issues that may have contributed to lower vaccination rates. This year, the updated COVID-19 vaccines will be available around the same time as flu vaccines, thanks to earlier CDC and FDA decisions.
The CDC recommends receiving the flu vaccine in September or October each year, which can be administered alongside the COVID-19 vaccine. “Co-administration is a best practice,” stated Dr. Demetre Daskalakis of the CDC during the AMA event, encouraging healthcare providers to offer both vaccines during the same visit when possible.
Health officials have acknowledged that the new COVID-19 vaccines might arrive too late for some Americans affected by this summer’s surge in infections. “Timing the COVID vaccine before an oncoming surge is challenging,” said Dr. Ruth Link-Gelles of the CDC, noting the difficulty of aligning vaccine distribution with the unpredictable waves of the virus.
Targeting the KP.2 Variant
The updated vaccines from Pfizer and Moderna are designed to target the KP.2 variant, a descendant of the JN.1 strain that contributed to last winter’s surge. This decision to focus on KP.2 differs from the World Health Organization’s recommendation, which suggested targeting the JN.1 variant.
Despite the FDA’s advisors recommending a focus on JN.1, the FDA chose to target KP.2 due to a recent rise in cases, aiming to better match the latest strains. However, KP.2 has been declining as a share of infections, with the KP.3.1.1 strain now accounting for over a third of cases, according to CDC estimates.
While the specific strain targeted by the vaccines may impact their effectiveness, experts believe the difference between these variants is relatively minor compared to past mutations. “All of these viruses currently circulating are very similar to each other,” explained CDC’s Natalie Thornburg during a recent call with testing labs, noting that the differing names primarily reflect nomenclature differences rather than significant genetic divergence.