

The FDA's vaccine advisory committee met to pick the COVID-19 strain for 2026–2027 shots, with a new recombinant variant called XFG emerging as the leading candidate. But the bigger story might be who's still showing up to get vaccinated at all.
Every spring, a group of scientists quietly picks which flu strains will go into next season's shots. It's been happening for decades, and nobody thinks twice about it. Now COVID vaccines get the same treatment.
On May 28, the FDA's advisory committee on vaccines (known as VRBPAC) convened to recommend the strain composition for the 2026–2027 COVID-19 vaccines. The meeting follows the same playbook as last year, and the year before that: review what's circulating, figure out what's gaining ground, and tell Moderna, Pfizer, and Novavax what to put in their shots for the fall.
Except this year, there's a new name on the whiteboard: XFG.
The virus hasn't been sitting still. While the 2025–2026 vaccines targeted the LP.8.1 strain (a descendant of the JN.1 lineage that dominated last year), the landscape has shifted. WHO is now tracking several newer Omicron sublineages, including NB.1.8.1, KP.3.1.1, BA.3.2, and the big one: XFG.
XFG is a recombinant variant, first documented in January 2025, that has spread across multiple continents. Reports indicate that VRBPAC was specifically asked to weigh whether 2026–2027 vaccines should target XFG, with FDA staff noting limited data on some of the currently circulating strains. Think of it like picking a fantasy football lineup when half the players haven't had their preseason yet.
The committee's final vote hasn't been officially published as of the meeting date. But the direction of travel is clear: XFG is the frontrunner for the updated formula.
If this process feels routine by now, that's actually the point. Back in 2022, the FDA made its first real-time strain swap when it authorized bivalent BA.4/BA.5 boosters. That was messy, controversial, and frankly a bit improvised.
Since then, the system has matured fast:

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Each year, VRBPAC reviews surveillance data, antigenic characterization (basically how well antibodies from current vaccines neutralize new variants), real-world effectiveness numbers, and manufacturing feasibility. Then FDA tells manufacturers exactly what to build. It's essentially the flu vaccine playbook, with one major difference: COVID strain selection is a U.S.-centric FDA process, while flu relies on a coordinated global WHO recommendation.
The result is a system where updated COVID shots show up at your pharmacy every fall, right alongside flu vaccines. Quiet, predictable, boring. Exactly what a mature public health process should be.
Once FDA locks in the strain, the manufacturing clock starts ticking. And this is where the platform differences really matter.
Moderna says it can have doses of the recommended 2026–2027 formula ready by mid-August. That's roughly a 10-to-12-week turnaround from a late-May decision, which is wild if you think about it. Reprogramming an mRNA vaccine is a bit like editing a Word document compared to reprinting an entire textbook.
Pfizer-BioNTech has signaled it's "ready to supply the updated formula upon approval," which suggests a similarly fast mRNA pivot.
Sanofi (which now partners with Novavax on the protein-based vaccine) has indicated it is prepared to produce XFG-targeting shots for the 2026–2027 season. Protein vaccines take longer to produce than mRNA, so Sanofi would need to start building before the committee even met. It's a calculated bet, like baking the cake before the birthday party guest of honor confirms the flavor.
For context, the current U.S. market includes four approved COVID vaccines: two Moderna formulations (Spikevax and mNexspike), Pfizer-BioNTech's Comirnaty, and Novavax/Sanofi's Nuvaxovid.
The real challenge for 2026–2027 isn't whether manufacturers can make the vaccines. It's whether anyone will actually get them.
Uptake has been falling off a cliff. During the 2025–2026 season, only about 15% of U.S. adults got their updated COVID shot by early December. Among adults 65 and older, the number was 32.5%. That's down from the prior year. Pandemic fatigue is real, risk perception has cratered, and the people still rolling up their sleeves are mostly seniors and those with chronic conditions.
The clinical case for vaccination remains solid: early effectiveness data for the 2025–2026 Pfizer vaccine showed it was roughly 57% effective at preventing ER and urgent care visits, and 54% effective against outpatient visits. That's actually comparable to how flu vaccines perform in a decent year. But "comparable to the flu shot" isn't exactly a rallying cry for the under-65 crowd.
COVID vaccines are settling into a pattern that looks a lot like the flu vaccine market: profitable, predictable, and dominated by a few big players.
Pfizer and Moderna will continue splitting the lion's share of a shrinking but still multi-billion-dollar annual franchise. Their competitive edge will increasingly come from combination respiratory vaccines (think COVID plus flu in a single shot) and efficient seasonal manufacturing, not pandemic-era emergency stockpiling.
Novavax occupies a niche: the protein-based option for people who don't want mRNA. It's a real segment, but it's small. Unless Novavax can undercut on price or show meaningfully better durability in specific populations, its role stays specialized.
The baseline scenario for 2026–2027, barring a scary new variant, is a market with low-teens percentage uptake among all adults and coverage in the 30s for seniors. A sudden, more severe variant could bump those numbers temporarily. Continued apathy could push them into single digits.
Either way, the annual COVID vaccine ritual is here to stay. It's just not the blockbuster event it used to be. More like the season finale of a show that's been on a few years too long: the dedicated fans still tune in, but the cultural moment has passed.
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