By Peter A. McCullough, MD, MPH
Its fall and another season of wasted government money on unpopular and rarely taken COVID-19 boosters. The 2026–2027 boosters from Pfizer/BioNTech, Moderna, and Novavax/Sanofi all target the XFG variant — and by the time they hit pharmacy shelves this week, the variant landscape has already moved. That’s not a coincidence of timing. It’s the structural reality of chasing a nonseasonal virus that mutates faster than the regulatory approval pipeline can move. The theoretical vaccine efficacy only lasts a few months.
🎯 What the Boosters Actually Cover
All three manufacturers’ 2026–2027 formulations are built around a single antigen target:
Pfizer/BioNTech (COMIRNATY® XFG) — mRNA, targets XFG
Moderna (Spikevax and mNexspike) — mRNA, targets XFG, a subvariant of the JN.1 lineage
Novavax (Nuvaxovid™, sold via Sanofi) — protein-based, targets XFG
That’s it. One strain, three products. The FDA selected XFG back in May 2026 based on what was circulating in the spring. The manufacturers’ own press materials claim the shots generate responses against other lineages — XFG.1.1, NB.1.8.1, PQ.17, PQ.2.8.1 — but the antigen itself is XFG, and the “broadening” is theoretical cross-reactivity, not a designed match.
