The Food and Drug Administration (FDA) is contemplating modifying the COVID-19 vaccines to specifically combat the latest omicron strain, Your Content has learned.
As the virus continues to evolve, today’s vaccines still contain the original coronavirus strain that initiated the pandemic.
However, FDA’s scientific advisers met on Thursday to discuss whether the upcoming shots in the United States should exclusively focus on protecting against the most recent dominant variants, particularly the XBB branch of the omicron family tree.
Dr. Peter Marks, the FDA’s vaccine chief, expressed concern about the potential resurgence of COVID-19 next winter as the virus evolves further and population immunity weakens.
Despite the decline in infections, the virus could pose a significant threat during the colder months when people tend to spend more time indoors.
The FDA intends to provide an updated vaccine against COVID-19 in the fall, akin to the annual flu shot.
Even though a significant portion of the population has either been infected or received at least one round of vaccinations, the continuous emergence of new coronavirus variants necessitates ongoing vaccine adaptations.
Currently, the U.S. utilizes combination shots from Pfizer and Moderna, which offer protection against both the original strain and last year’s common omicron variants (BA.4 and BA.5). However, only 17% of Americans have received the combination booster shot.
Furthermore, while seniors and high-risk individuals were permitted to receive an additional booster dose this spring, the majority of people will have gone several months without a vaccination by fall.
This ongoing exposure to the original strain has led to a phenomenon known as “imprinting,” wherein the immune system recognizes and responds more strongly to the original strain rather than the novel components of a booster dose. Consequently, the FDA is leaning toward excluding the original strain in the fall shot formulation and focusing solely on XBB.
The hope is that the XBB variants exhibit sufficient differences to stimulate the immune system into producing a broader range of virus-fighting antibodies with cross-protective capabilities. Similar recommendations have recently been made by the World Health Organization’s vaccine advisers and European regulators.
An additional challenge lies in deciding which specific XBB variant to target, as the current circulating variants will likely have undergone further mutations by winter. Regulatory authorities will rely on their best estimation, much like the annual formulation of the fall flu vaccine.
The FDA has identified three prominent XBB subtypes as the primary choices. Vaccine manufacturers are already developing formulas tailored to target XBB, and the FDA’s external advisers will review new data on the effectiveness of these choices in boosting the immune response.
The number of additional shots required will also be subject to debate among the FDA’s advisers.
Older adults and individuals with compromised immune systems continue to experience higher hospitalization rates from COVID-19, even as cases decline. The question arises as to whether they should receive a single fall shot or be eligible for multiple doses. Moreover, determining the vaccination regimen for young children who have not yet been vaccinated will be another consideration, according AP News.
Ultimately, the final recommendations regarding the fall COVID-19 vaccine will be made by the Centers for Disease Control and Prevention (CDC).