The clinical trials for the mRNA flu vaccine showed an 8% absolute risk reduction and a significant side effect profile.

We revised this check on Nov 8, 2026. See what changed and why ↓

The finding

What the evidence shows

The trial found 2.0% versus 2.8% protocol-defined influenza illness against a standard-dose comparator, about 0.8 percentage points absolute difference and 26.6% relative efficacy. This does not support the broad claim that it did not work. Means raises a legitimate comparator-design question for older adults; this trial does not prove superiority to every enhanced vaccine. Captions render the number as 8%, so a spoken decimal error must not be asserted without audio confirmation.

Read the supporting source · www.fda.gov ↗

Quick answer & review status

Quick answer

Is it true that the clinical trials for the mRNA flu vaccine showed an 8% absolute risk reduction and a significant side effect profile?

Partly. The claim stretches what the evidence shows. 6% relative efficacy. This does not support the broad claim that it did not work. Calley Means said it (matched by voice) on Joe Rogan Experience #2578 - Calley Means, aired Nov 6, 2026, at 1:37:31. The supporting source is fda.gov, linked below.

The context belongs here.

No separately verified on-air correction is recorded for this check. That is not a claim that nobody corrected it.

Attribution: Not independently confirmed in this record
Editorial context review: Not recorded; generated finding
Coverage: One selected claim from the episode

Revisions to this check

Nov 8, 2026

Previously: The clinical trials for the mRNA flu vaccine showed an 8% absolute risk reduction and a significant side effect profile. [Distorted]: In the phase 3 trial of about 40,000 adults aged 50 and older, 2.0% of people given the mRNA flu shot got lab-confirmed flu, compared with 2.8% given a standard-dose shot. That is an absolute difference of about 0.8 percentage points, not 8%, and a 26.6% relative efficacy against an already-licensed vaccine. Short-lived reactions such as arm pain were more common with the mRNA shot (65.8% vs 29.8%), but serious adverse events were similar (2.2% vs 1.9%). This verdict would be wrong if the FDA review or the NEJM paper reports an absolute risk reduction near 8%.

Now: The clinical trials for the mRNA flu vaccine showed an 8% absolute risk reduction and a significant side effect profile. [Distorted]: The trial found 2.0% versus 2.8% protocol-defined influenza illness against a standard-dose comparator, about 0.8 percentage points absolute difference and 26.6% relative efficacy. This does not support the broad claim that it did not work. Means raises a legitimate comparator-design question for older adults; this trial does not prove superiority to every enhanced vaccine. Captions render the number as 8%, so a spoken decimal error must not be asserted without audio confirmation.

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