On Thursday, January 26, the FDA’s Vaccine and Related Biological Products Advisory Committee is expected to vote on a newly proposed COVID-19 vaccine schedule.
Under the new proposal, the FDA would conduct an assessment of prevalent strains circulating each year, likely beginning around June, with the aim of new vaccines being ready by September.
Taking a similar approach as it does to the flu vaccine, the FDA proposal recommends that most adults receive a single annual shot in the later months of each calendar year. Certain young children, older adults, and persons with compromised immunity would be recommended for a two-dose series.
The FDA outlined its reasoning behind the proposed shift toward a more standardized schedule in a public briefing document released in advance of the meeting,
The epidemiology aspect: Annually tailoring vaccines to address new circulations
The first reason for an annual recommended dose of the vaccine is related to the continuation of mutations in the underlying virus. Ongoing updates to the vaccine will likely be necessary in order to tailor it to future variants resulting from these mutations, and to combat waning effectiveness, the FDA wrote in the public briefing document.
“Given the evolution of SARS-CoV-2 variants and associated changes in the epidemiology, susceptibility to reinfection, and waning of vaccine-induced immunity, barring development of a significantly improved vaccine, periodic future updates to the S protein sequence(s) contained or encoded in COVID-19 vaccines and revaccination will likely be needed to induce and maintain vaccine effectiveness (VE), respectively,” the document said.
The “human factors” aspect: Simplifying schedules for the sake of convenience
In addition to the epidemiological argument for annual vaccines, the FDA also shared another argument for the shift: simplicity.
“This simplification of vaccine composition should reduce complexity, decrease vaccine administration errors due to the complexity of the number of different vial presentations, and potentially increase vaccine compliance by allowing clearer communication,” the briefing document said.
As the globe prepares to enter into a stage of endemic COVID-19, the FDA will continue to advise accordingly.