For all the coronavirus variants that have thrown pandemic curve balls — including alpha, beta, gamma and delta — COVID-19 vaccines have stayed the same. That could change this fall.
On June 28, an advisory committee to the U.S. Food and Drug Administration met to discuss whether vaccine developers should update their jabs to include a portion of the omicron variant — the version of the coronavirus that currently dominates the globe. The verdict: The omicron variant is different enough that it’s time to change the vaccines. Those shots should be a dual mix that includes both a piece of the nearly identical omicron subvariants BA.4/BA.5 and the virus from the original vaccines, the FDA announced June 30.
“This doesn’t mean that we are saying that there will be boosters recommended for everyone in the fall,” Amanda Cohn, chief medical officer for vaccine policy at the U.S Centers for Disease Control and Prevention said at the meeting. “But my belief is that this gives us the right vaccine for preparation for boosters in the fall.” The decision to update COVID-19 vaccines didn’t come out of nowhere. In the two-plus years that the coronavirus has been spreading around the world, it has had a few “updates” of its own — mutating some of its proteins that allow the virus to more effectively infect our cells or hide from our immune systems.
Vaccine developers had previously crafted vaccines to tackle the beta variant that was first identified in South Africa in late 2020. Those were scrapped after studies showed that current vaccines remained effective.
The current vaccines gave our immune systems the tools to recognize variants such as beta and alpha, which each had a handful of changes from the original SARS-CoV-2 virus that sparked the pandemic. But the omicron variant is a slipperier foe. Lots more viral mutations combined with our own waning immunity mean that once omicron can gain a foothold in the body, vaccine protection isn’t as good as it once was at fending off COVID-19 symptoms (SN: 6/27/22).
The shots still largely protect people from developing severe symptoms, but there has been an uptick in hospitalizations, especially among older people, Heather Scobie, deputy team lead of the CDC’s Surveillance and Analytics Epidemiology Task Force said at the meeting. Deaths among older age groups are also beginning to increase. And while it’s impossible to predict the future, we could be in for another tough fall and winter, epidemiologist Justin Lessler of the University of North Carolina at Chapel Hill said at the meeting. From March 2022 to March 2023, simulations project that deaths from COVID-19 in the United States might number in the tens to hundreds of thousands.
A switch to omicron-containing jabs may give people an extra layer of protection for the upcoming winter. Pfizer-BioNTech presented data at the meeting showing that updated versions of its mRNA shot gave clinical trial participants a boost of antibodies that recognize omicron. One version included omicron alone, while the other is a twofer, or bivalent, jab that mixes the original formulation with omicron. Moderna’s bivalent shot boosted antibodies too. Novavax, which developed a protein-based vaccine that the FDA is still mulling whether to authorize for emergency use, doesn’t have an omicron-based vaccine yet, though the company said its original shot gives people broad protection, generating antibodies that probably will recognize omicron.
Pfizer and Moderna both updated their vaccines using a version of omicron called BA.1, which was the dominant variant in the United States in December and January. But BA.1 has siblings and has already been outcompeted by some of them.
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