The Food and Drug Administration (FDA) has approved updated versions of the Pfizer/BioNTech Comirnaty and Moderna Spikevax COVID-19 vaccines, specifically targeting the Omicron KP.2 strain of SARS-CoV-2. This decision marks a crucial step in adapting to the evolving landscape of COVID-19 variants and aims to bolster protection for the upcoming 2024-25 vaccination season.
Both mRNA-based vaccines have been approved for individuals aged 12 years and older and have received emergency use authorization for children aged 6 months to 11 years. Drugmakers anticipate availability within the next few days. Peter Marks, director of the FDA's Center for Biologics Evaluation and Research (CBER), emphasized that "vaccination continues to be the cornerstone of COVID-19 prevention."
Addressing Variant Evolution and Immunity
The KP.2 strain, an offshoot of the JN.1 lineage of Omicron, prompted the FDA to advise vaccine manufacturers in June to target this variant for the updated shots. While KP.2 is already being superseded by the KP.3 strain, Pfizer/BioNTech and Moderna anticipate their vaccines will maintain protective efficacy due to the similarity between the two strains. This shift reflects an approach similar to annual influenza vaccine updates.
Given the waning immunity from previous exposures and vaccinations, the FDA strongly encourages eligible individuals to consider receiving an updated COVID-19 vaccine. This recommendation is particularly important as vaccination rates have declined since the declared end of the COVID-19 pandemic.
Broader Vaccination Efforts and Access
In the United States, the Centers for Disease Control and Prevention (CDC) recommends that everyone over six months old receive an updated COVID-19 vaccine this year. However, access to free shots is becoming limited outside of federal assistance programs for those with inadequate insurance, and these schemes are set to expire soon. This raises concerns about equitable access to vaccination, especially for vulnerable populations.
Alternative Vaccine Approaches
Novavax, another player in the COVID-19 vaccine market, has filed for approval of a non-mRNA vaccine based on the earlier JN.1 variant. The company is collaborating with the FDA to align with the KP.2 target and anticipates authorization in time for the peak vaccination season. This provides an alternative option for individuals who may prefer a non-mRNA vaccine.
Combination Vaccines and Future Prospects
Both Moderna and Pfizer/BioNTech are also developing combined COVID-19/flu vaccines. Moderna is aiming for potential approval of its candidate in 2025 or 2026, while Pfizer/BioNTech recently experienced a setback in a phase 3 trial, delaying their program. The development of combination vaccines represents a potential advancement in simplifying vaccination schedules and improving public health outcomes.
