U.S. weighs fourth booster as BA.2 subvariant threatens next COVID wave
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As the highly infectious BA.2 version of the Omicron variant spreads across the globe, federal regulators and health officials continue to debate whether a fourth coronavirus shot is needed. The subvariant made up an estimated 34% of U.S. cases in the week of March 19, up from 23% and 13% in the weeks prior, according to the CDC. Some countries have already approved second boosters, like Israel, Germany, Spain and Sweden, but the U.S. is still debating its move forward, while a $15B spending package remains stalled in Congress that could place advance orders for additional vaccines.
Funding concerns: "Right now, we don't have enough money for fourth doses, if they're called for," White House coronavirus coordinator Jeff Zients told podcast In The Bubble With Andy Slavitt. "We [also] don't have the funding if we were to need a variant-specific vaccine in the future."
Last week, Pfizer (NYSE:PFE) and partner BioNTech (NASDAQ:BNTX) announced they had submitted an application to the FDA for Emergency Use Authorization of an additional booster for adults 65 years of age and older. "Data showed rates of confirmed infections were 2 times lower and rates of severe illness were 4 times lower among individuals who received an additional booster dose, compared to individuals who received only an initial booster," according to the companies. A few days later, Moderna (NASDAQ:MRNA) said it will seek approval for a second booster shot in all adults, and while the data is still coming in, some medical experts have flagged concerns with the applications.
Outlook: "I hate to even bring this up, but there's evidence from studies in mice that repeated immunizations, with the intervals too short, you can actually start to induce tolerance, and that's the last thing you want," said Dr. James Hildreth, a leading immunologist who advises the FDA on vaccines. "I would much prefer the focus being on looking at the sequences that have come out from the variants that we've dealt with, and try to do a vaccine that would offer protection against those, as opposed to just giving people a fourth shot [that is tailored to a two-year-old virus]."