Safety and Effectiveness of New COVID Bivalent Boosters Based on a Study of Eight Mice?

With no safety and efficacy evidence from human clinical trials, on Aug. 31, 2022, the U.S. Food and Drug Administration (FDA) amended the Emergency Use Authorizations (EUAs) for Pfizer/BioNTech’s Comirnaty and Moderna/NIAID’s Spikevax messenger RNA (mRNA) COVID-19 biologics to distribute “bivalent formulations” (two-in-one) of the shots to use as a “single booster dose.”^{1 2}

The so-called “updated boosters” contain two mRNA “components” of the SARS-CoV-2 virus—”one of the original strain of SARS-CoV-2 and the other one in common between the BA.4 and BA.5 lineages of the Omicron variant of SARS-CoV-2.”^{1 2}

The FDA authorized Moderna/NIAID’s COVID Bivalent shot for use in individuals 18 years of age and older and authorized Pfizer/BioNTech’s COVID Bivalent for those 12 years of age and older. With this new EUA, the original “monovalent” versions of the Moderna/NIAID and Pfizer/BioNTech mRNA COVID shots will no longer be distributed as booster doses for individuals 12 years of age and older.^{1 2}

FDA Evaluated Data from One Clinical Study on Eight Mice

According to the FDA, it “evaluated immunogenicity and safety data from a clinical study of a booster dose of a bivalent COVID-19 vaccine that contained a component of the original strain of SARS-CoV-2 and a component of Omicron lineage BA.1.” The agency stated that it considered the data as “relevant and supportive” of the biologics “containing a component of the Omicron variant BA.4 and BA.5 lineages.”²

What the FDA failed to mention, however, is that the data from that single clinical study was obtained from mice. Eight mice, to be precise. There were no human trials.

“Both shots have yet to complete human trials,” noted a recent CNBC article. “The FDA based its decision off real-world evidence of existing COVID vaccine safety, plus clinical trial data of earlier bivalent vaccines targeting older forms of Omicron and current lab data on the BA.5 shot in mice.”³

Mouse Data Does Not Mimic Reactions in Humans

In response, John Moore, PhD, professor of microbiology and immunology at Weill Cornell Medical College, wrote:

To rely only on mouse data (for authorization) would be unprecedented in my knowledge and would certainly raise eyebrows. It doesn’t mimic the human situation.⁴

Additionally, Dr. Moore pointed out that the FDA was is also bypassing the normal protocol of earlier COVID shot reviews and not having a meeting of advisers who make recommendations on whether the agency should authorize a vaccine.⁴

On Aug. 31, Johns Hopkins University medical professor and National Academy of Science member Marty Makary, MD, MPH wrote:

FDA will likely authorize the Omicron vaccine later today/tomorrow based on data from 8 mice and no human clinical data avail to the public. Americans deserve to see the data. Why is the White House/Dr. Jha pushing it so hard & universally w/o public data?⁵

No Time to Wait for Results of Human Trials

The reason for this “fast-tracking” of the COVID Bivalent shots was explained by Rochelle Walensky, MD, director of the U.S. Centers for Disease Control and Prevention (CDC), who said:

If we wait for those data to emerge in human data, not just mice data, we will be using what I would consider to be a potentially outdated vaccine. And maybe it’s best, and I believe it is best, to use a vaccine that’s tailored for the variant that we have right now.^{3 6}

So the strategy now is to tailor vaccines for giving us the largest breadth of response. Ideally one that would have less waning over time, and that is by targeting what I would say is the most proximal variant, the one that we have closest to us, which is BA.4 and BA.5. And I believe there’s significant upsides to doing that with this updated bivalent vaccine and very little downside in doing so.⁶

In a time of… We could either be too slow or too fast, I really would love to be ahead of this variant this season.⁶

In other words, the U.S. government simply may have felt it didn’t have the luxury of waiting for clinical data on humans because the fall “flu season” is fast approaching and there are predictions that the season will also bring on a surge of COVID cases, making for a potentially nasty “twindemic.”⁷

Some are pointing to upcoming U.S. mid-term elections in November as a reason for the rush to put a new COVID booster on the market without safety and efficacy data in humans so government health officials can reassure the public that the re-worked shot will cut down on the significant number of breakthrough COVID cases being reported in fully vaccinated and boosted people. Epidemiologist Vinay Prasad, MD, MPH tweeted:

If u have election in Nov, u’d approve anything to lower cases right before the vote. Who cares about safety/ severe dx⁵

Both Moderna and Pfizer are currently conducting clinical studies on humans, but the results of those studies are, reportedly, not due to be released until October or November. By then, millions of Americans will have received the COVID Bivalent boosters… in essence, making them the actual test cases for these experimental products.⁸

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