The US Food and Drug Administration (FDA) has approved updated COVID-19 vaccines from Pfizer/BioNTech and Moderna to better protect against currently circulating variants.
The updated vaccines target the KP.2 strain, a descendant of the JN.1 variant that was circulating in the US earlier this year, and are expected to be available in the coming days.
Both mRNA vaccines have been approved for use in individuals aged 12 years and older, and have been granted emergency use authorisation for those aged six months to 11 years.
The adaptations are based on recent guidance from the FDA, which advised COVID-19 vaccine manufacturers in June that vaccines for the upcoming autumn/winter programme should target KP.2 “if feasible”.
KP.2 is no longer the dominant strain and now only accounts for 3.2% of COVID-19 cases across the country, according to the latest Centers for Disease Control and Prevention data, but is still related to other currently circulating variants.
Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research, said: “These updated vaccines meet the agency’s rigorous, scientific standards for safety, effectiveness and manufacturing quality.
“Given waning immunity of the population from previous exposure to the virus and from prior vaccination, we strongly encourage those who are eligible to consider receiving an updated COVID-19 vaccine to provide better protection against currently circulating variants.”
The FDA has outlined that it anticipates that the composition of COVID-19 vaccines will need to be evaluated annually, as occurs for seasonal influenza vaccines.
Pfizer/BioNTech and Moderna have been developing combination vaccines for flu and COVID-19.
Top-line results from a late-stage study of Pfizer and BioNTech’s candidate were announced earlier this month. The trial met one of its two primary immunogenicity endpoints, but despite eliciting higher influenza A immune responses compared to a standard flu vaccine comparator, the combination candidate showed weaker results against the influenza B strain.
Moderna also recently shared positive phase 3 results for its own flu/COVID-19 combination vaccine candidate and said it will “engage with regulators on next steps”.