Aug. 10 at 11:47 AM
$VXRT $SNY @Scootermn Page 1
As we have seen from others from AI contributions, these programmes are as good as their input and often limit their output by referencing publicly available information only.
With thisin mind, I was intrigued how the simplest question at outset,led Chat GPT on a voyage of discovery where it changed course without prompt. A definite shift the more it explored for self, I appreciate a long read but a comprehensive path which leads us to impending huge flu funding awards and context of an imminent acquisition.
Cheat by skipping to final paragraphs if wish, but the story best unfolds if don’t !!
When Moderna flu vaccine was approved last week, did Sanofi make any public comment ?
I can find no public comment from Sanofi so far specifically responding to the FDA's approval of Moderna's mFlusiva on August 5, 2026.
That silence is noteworthy because Moderna's approval puts a new competitor directly into an important Sanofi franchise. mFlusiva is the first FDA-approved seasonal influenza vaccine using mRNA, approved for adults 50+, and Moderna's Phase 3 study reported 26.6% greater relative efficacy than a standard-dose flu vaccine. Reuters also reports that it generated stronger antibody responses than Sanofi's high-dose vaccine in seniors. (Reuters)
I searched Sanofi's own recent communications as well as broader coverage and couldn't locate a statement from Sanofi management, Vaccines, investor relations, or a quoted Sanofi spokesperson reacting to the decision.
Why the absence of comment is interesting
Sanofi has several possible ways it could have responded: defend the established evidence for its influenza portfolio, emphasize Fluzone High-Dose/Flublok, question whether immunogenicity comparisons translate into clinical superiority, or simply welcome innovation in influenza vaccination. It appears to have done none of those publicly.
There is an important commercial qualification, however. Reuters reports that Moderna isn't expected to have a substantial commercial impact until the second half of 2027 because it missed the contracting cycle. (Reuters) So Sanofi doesn't necessarily have an immediate 2026-season competitive problem.
In the context of the Sanofi/Vaxart question we've been examining, I think the development is particularly relevant. It strengthens the strategic argument for why Sanofi would care about a differentiated next-generation influenza technology. Moderna has now demonstrated that an alternative platform can break into a market where Sanofi has a major incumbent position. An effective oral/mucosal influenza vaccine would potentially provide Sanofi with a differentiation that isn't simply "another injected flu vaccine competing with Moderna."
What I wouldn't infer is that Sanofi's silence itself is evidence of a Vaxart transaction. There are perfectly ordinary reasons not to comment publicly on a competitor's FDA approval.
But there's a more revealing question we can investigate: what Sanofi has said about the future competitiveness of its flu franchise in its most recent investor presentations and earnings calls, particularly anything said before versus after Moderna's Phase 3 results. That could tell us considerably more than whether Sanofi issued a congratulatory or defensive statement last week.
Please investigate
Yes. I went back through Sanofi's investor presentations, pipeline updates and flu communications, including material from before Moderna's decisive Phase 3 result in June 2025 through Sanofi's latest Q2 2026 presentation on July 30. There has been a meaningful evolution in Sanofi's flu strategy, and I think it is relevant to the Vaxart question.
1. Sanofi once intended to compete with Moderna directly in seasonal mRNA flu
In 2021–23, Sanofi was explicitly developing its own seasonal mRNA influenza vaccine. At its June 2023 Vaccines Investor Event, Sanofi devoted several slides to SP0273, its quadrivalent mRNA flu vaccine. It even put its results alongside Moderna's earlier mRNA data.
Sanofi's assessment at the time wasn't particularly flattering to mRNA. Its own presentation said its mRNA candidate produced A-strain responses comparable with standard of care but B-strain responses that "trend lower than SoC." It went further and suggested that low B-strain response was a "class effect across mRNA platforms."
Sanofi nevertheless described this as a "comprehensive mRNA flu vaccine program." (sanofi.com)
That is an important baseline.
2. Sanofi subsequently changed direction
By 2024, Sanofi's investor message had changed substantially.
Instead of presenting seasonal mRNA as the route to the next generation of influenza vaccines, its July 2024 results presentation had a slide entitled:
"Flu: strengthening leadership"
But the strategy underneath was:
Sanofi's established differentiated flu vaccines;
the Novavax partnership for a non-mRNA flu/COVID combination;
pandemic H5 preparedness, including both conventional and mRNA approaches.
Sanofi specifically described the Novavax combination as potentially providing improved tolerability compared with mRNA-based COVID combinations. (sanofi.com)
The May 2024 Sanofi-Novavax announcement was similarly explicit: Sanofi said it saw an opportunity to develop "non-mRNA flu-COVID-19 combination vaccines" using Sanofi's differentiated flu products. (sanofi.com)
So by this point the strategy was no longer, "We need our own seasonal mRNA flu vaccine."
3. Then Moderna produced the result that changed the competitive equation
On June 30, 2025, Moderna announced the critical Phase 3 efficacy result.
In more than 40,000 adults 50+, mRNA-1010 demonstrated 26.6% superior relative vaccine efficacy to the licensed standard-dose comparator; the advantage in adults ≥65 was 27.4%. (Reuters)
This mattered because Sanofi's 2023 presentation had essentially argued that mRNA flu still exhibited important immunogenicity shortcomings.
Moderna subsequently demonstrated actual clinical superiority against influenza illness, rather than merely higher antibody titres.
And FDA has now approved mFlusiva for people aged 50+, making it the first approved mRNA influenza vaccine in the US. (U.S. Food and Drug Administration)
4. Sanofi's answer has not been to resurrect its seasonal mRNA programme
This is probably the most interesting finding.
I checked Sanofi's current pipeline, updated July 30, 2026.
There is an mRNA influenza vaccine there — SP0289 — but its indication is pandemic H5 influenza.
I do not find the old SP0273 seasonal quadrivalent mRNA programme in the current clinical pipeline.
Instead, Sanofi's present seasonal strategy contains:
Fluzone High-Dose
→ expansion of the high-dose vaccine to people aged 50+.
SP0287 — Fluzone HD + Nuvaxovid
→ the non-mRNA influenza/COVID combination.
SP0289
→ mRNA for H5 pandemic influenza, rather than routine seasonal flu. (sanofi.com)
That distinction is significant.
5. And look at what Sanofi did with Fluzone High-Dose
Rather than attempting to meet Moderna by developing another seasonal mRNA product, Sanofi has been aggressively strengthening its incumbent differentiated vaccine.
In October 2025 Sanofi announced data from the enormous FLUNITY-HD programme showing that its high-dose vaccine reduced influenza-related hospitalization versus standard-dose vaccines in people 65+. (sanofi.com)
Then Sanofi sought to extend Fluzone HD/Efluelda down from the traditional older population to everyone aged 50+.
As of April 2026, both FDA and EMA had accepted those applications for review. (sanofi.com)
Notice the competitive geometry.
Moderna mFlusiva: 50+
versus
Sanofi Fluzone HD proposed expansion: 50+
That puts the products increasingly into the same target population.
6. Sanofi is therefore defending the franchise through differentiation, not mRNA imitation
The wording Sanofi uses repeatedly is telling.
It doesn't simply describe Fluzone HD and Flublok as flu vaccines. It calls them "differentiated flu" vaccines.
Its argument is essentially:
standard flu vaccine
→ enhanced/differentiated vaccine
→ demonstrated clinical protection
→ hospitalization reduction
→ superior protection for older adults.
Back in 2021 Sanofi explicitly said differentiated flu products represented roughly two-thirds of Sanofi's flu sales, and described market preference as recognition of "superior protection." (sanofi.com)
That strategy persists.
7. But Moderna has now attacked precisely that differentiation argument
There is an important nuance in last week's approval.
Moderna's 26.6% efficacy advantage was against a standard-dose vaccine, not Fluzone High-Dose.
For ≥65s, mFlusiva's FDA indication is under accelerated approval based on immune response, with confirmatory evidence still required. (mNEXSPIKE)
However, Reuters reports that Moderna generated stronger antibody responses than Sanofi's high-dose vaccine in seniors. (Reuters)
So Sanofi cannot simply dismiss Moderna as another standard flu vaccine.
The competitive question has become:
Which "enhanced" vaccine is best for older adults — Sanofi's high-dose/protein approaches or Moderna's mRNA approach?
That is much more consequential for Sanofi.
8. Sanofi's Q2 presentation immediately before the approval is revealing
Sanofi reported Q2 results on July 30, 2026 — only six days before Moderna's FDA approval.
There was no big strategic warning about Moderna.
Instead Sanofi explained declining vaccine sales largely as a comparison/seasonality issue. Its slide said:
"Vaccines — Decline from high basis of comparison in flu."
The detailed flu/COVID category fell 61.7% year over year, from €141m to €54m in Q2, which Sanofi attributed to a high comparison and a lower Southern Hemisphere season. (sanofi.com)
