The Food and Drug Administration (FDA) is set to convene a meeting on Thursday to deliberate on updates for the next round of COVID boosters, with a particular emphasis on targeting XBB strains that may circulate in the coming fall.
The FDA's crucial decision-making process aims to ensure that drug manufacturers have sufficient time to produce the updated shots.
Drawing inspiration from the annual flu shot selection process, scientists will assess the prevalent strains and make informed predictions about the most prominent ones to be included in the vaccine.
FDA Evaluates the Need for Updated COVID Boosters
According to Politico, in their ongoing efforts to combat the evolving landscape of COVID-19, the FDA is gearing up for its second update to the COVID vaccines.
Previously, in December 2020, the FDA authorized the initial versions of the vaccines, which solely targeted the original coronavirus strain.
Last year's update granted authorization for shots designed to tackle the original strain, along with the BA.4 and BA.5 omicron subvariants, although these strains are no longer in circulation within the United States.
With the new round of updates on the horizon, the FDA's focus now turns to addressing the XBB strains.
These variants, originating from two omicron subvariants and first surfacing in October, have continued to emerge since last fall.
As of the latest data from the CDC, XBB.1.5 is currently the dominant strain in the United States, accounting for approximately 40% of all new COVID cases.
Following closely are XBB.1.16, nicknamed "Arcturus" on social media, and XBB.1.9.1, comprising approximately 18% and 12% of new cases, respectively.
Fortunately, the XBB strains have not caused a surge in cases comparable to previous variants.
In their briefing documents released on Monday, FDA scientists highlighted the importance of redesigning boosters to specifically target the circulating omicron sublineages more closely.
Real-world studies have revealed that the current updated boosters in use in the U.S. do offer protection against XBB.1.5, albeit with lower antibody levels compared to the immunity conferred against BA.4 and BA.5.
According to Reuters, based on these findings, the scientists recommend an updated strain composition for COVID-19 vaccines to enhance their effectiveness during the 2023-2024 vaccination campaign.
Determining the Specific XBB Lineage for Boosters
The World Health Organization (WHO), following suit, recommended in May that the forthcoming round of COVID boosters focus on XBB subvariants.
According to NBC News, echoing this sentiment, the European Medicines Agency also endorsed the WHO's recommendation in June.
Notably, the WHO traditionally offers recommendations for the annual flu vaccine, which countries, including the United States, typically adhere to.
The FDA's Vaccines and Related Biological Products Advisory Committee, composed of knowledgeable experts, will play a crucial role in the decision-making process.
During Thursday's meeting, the committee members will deliberate on which particular XBB lineage should be incorporated into the vaccine.
However, it remains uncertain if the updated vaccines will be recommended for everyone in the upcoming fall.
In parallel, the CDC's Advisory Committee on Immunization Practices is scheduled to convene next week to discuss updated COVID boosters, along with other vaccine-related matters.
Regarding the composition of the new vaccines, the inclusion of the original coronavirus strain, identified in late 2019, remains undecided.
The WHO proposed a monovalent vaccine approach, targeting only one circulating strain, while FDA scientists also mentioned the idea in their briefing documents.
Dr. Isaac Bogoch, an infectious disease specialist at the University of Toronto, questions the added benefit of including the original strain given the substantial divergence of current circulating strains from the original variant.
As the FDA advisers gather on Thursday, their discussions will shape the future of COVID boosters, aiming to tackle the emerging XBB strains and ensure the ongoing protection of the population against the ever-evolving landscape of the virus.
