The FDA has provided instructions to Covid vaccine manufacturers on what strains to target for the upcoming fall’s Covid vaccines. The agency signaled a preference for updating the strain in the vaccines to a version of the virus that is currently circulating widely, LP.8.1.
The decision leaves room for Novavax, a company that requires months of lead time for its vaccine production, to continue using an older version of the virus. During a meeting of the FDA’s expert vaccines panel, Novavax expressed a preference to stick with the older version.
The instructions were posted on the FDA’s website shortly after the Vaccines and Related Biological Products Advisory Committee meeting, where the panel discussed the benefits and drawbacks of updating the vaccine strains for the fall. The committee members appeared divided on whether manufacturers should update their targets or stick with the same strain.
The FDA advised manufacturers to use monovalent JN.1-lineage-based Covid-19 vaccines for the fall of 2025, preferably targeting the LP.8.1 strain. This recommendation aligns with the World Health Organization’s advisory committee, which suggested manufacturers could choose between JN.1, KP.2, or LP.8.1 strains.
During the VRBPAC meeting, concerns were raised about potential testing requirements that could delay vaccine delivery for the fall if the strain was changed. Some committee members were not convinced that an update would significantly improve protection.
The FDA’s newly proposed Covid vaccine regulatory framework, published by FDA Commissioner Marty Makary and Vinay Prasad, suggests that Covid vaccines may only be available to high-risk individuals. The framework calls for new randomized controlled trials in younger, healthy adults to assess the benefits of vaccination.
Manufacturers may be required to produce human immunogenicity data to support the approval of updated products, which could prolong the availability of the vaccines. The FDA has not specified the size of these studies or if they will be necessary.
Moderna and the Pfizer-BioNTech partnership seem prepared to target the LP.8.1 strain, given their short production time using messenger RNA technology. However, Novavax, which requires more lead time, expressed a preference for sticking with the JN.1 virus used in its previous vaccine.
The meeting marked the first time since the Trump administration that the VRBPAC was convened. The committee was not consulted earlier for the strains in next winter’s flu shot, as the FDA issued orders based on recommendations from a WHO-led meeting in February.
Overall, the FDA’s instructions on updating Covid vaccine strains for the fall of 2025 have sparked discussions and considerations among manufacturers and experts in the field. The decision to target the LP.8.1 strain reflects ongoing efforts to adapt to the evolving nature of the virus and provide optimal protection for the population. The importance of transparency in the approval and monitoring process of Covid vaccines cannot be overstated. As Professor Monto, a respected figure in the field of public health, emphasized during a recent meeting, transparency is crucial for maintaining public trust and confidence in the vaccination efforts.
In a recent development, the FDA has mandated Pfizer and Moderna to include expanded warning labels on their Covid vaccine products. This decision comes in response to the emergence of a rare side effect known as myocarditis, which involves inflammation of the heart muscle. While this side effect has been predominantly observed in teenage boys, it has also been reported in individuals who have received the Covid vaccine, particularly following the administration of two doses within a short interval.
Data presented to the CDC’s expert panel revealed a decrease in the number of myocarditis cases linked to Covid vaccination since 2021. This trend suggests that ongoing monitoring and surveillance efforts are effective in identifying and addressing potential risks associated with the vaccines.
It is worth noting a correction to a previous statement regarding the European Medicines Agency’s role in selecting the target version of the Covid virus for vaccine development. The agency does not give vaccine manufacturers a choice in this matter, underscoring the rigorous regulatory standards that govern vaccine production and distribution.
Overall, these updates underscore the importance of continuous monitoring, transparency, and collaboration among regulatory bodies, healthcare professionals, and vaccine manufacturers to ensure the safety and efficacy of Covid vaccines. By prioritizing public health and safety, we can navigate the challenges posed by the pandemic and work towards a brighter, healthier future for all.
