The FDA has approved Pfizer and Moderna’s new 2026–2027 XFG-adapted mRNA COVID-19 vaccines even though the XFG-specific evidence publicly presented to regulators was preclinical animal data involving just 8–10 mice per group.
The reach of these dangerous approvals is sweeping: Pfizer can now be given to every American age 65 and older and to “high-risk” individuals as young as 5, while Moderna extends all the way down to “high-risk” infants just 6 months old.
The human safety and immunogenicity studies of the new formulations had not even begun when FDA granted approval.
Pfizer’s new COMIRNATY formulation was approved on August 27, 2026, while its prospective human study of the 2026–2027 formula is scheduled to begin August 31—four days later.
Moderna’s new SPIKEVAX formulation was also approved on August 27, but its Phase 3b/4 human study of the 2026–2027 SPIKEVAX and MNEXSPIKE formulations is not scheduled to begin until November 16—nearly three months after approval.
FDA’s own 2026 vaccine-selection materials distinguish between human data from earlier/current COVID vaccines and animal immunogenicity data for the new candidate vaccines.
Pfizer’s FDA presentation shows the XFG candidate was tested in 10 mice per group.
Moderna’s FDA presentation shows its key XFG experiment used 8 mice per group.
The approval letters reveal another troubling development: FDA also released both manufacturers from previously required placebo-controlled postmarketing studies, citing operational and feasibility problems. Pfizer’s abandoned study would have investigated circulating spike antigen and post-vaccination symptoms, while Moderna’s would have evaluated safety of variant-containing formulations.
Rather than requiring new human data before approval, FDA relied in part on human safety and immunogenicity data from previous COVID-19 vaccine formulations and extrapolated that evidence to the newly updated XFG products, while the XFG-specific evidence itself remained preclinical.
This reliance on older-formulation data is especially concerning given the millions of deaths, injuries, and disabilities, along with demonstrated cardiotoxicity, neurotoxicity, carcinogenicity, body-wide biodistribution, and years-long persistence.
This is extremely worrisome and needs to be reversed immediately.
Epidemiologist and Foundation Administrator, McCullough Foundation
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Do Not take any of these shots! They are based on population control! Truth
How does this keep happening if the FDA is under HHS? Why isn’t Secty Kennedy taking action to block these approvals?