Sanofi stock is under pressure on December 15, 2025, after the French drugmaker disclosed two setbacks tied to its experimental multiple sclerosis (MS) medicine tolebrutinib—a regulatory delay in the U.S. for one progressive MS form and a failed Phase 3 endpoint in another. The update pushed Sanofi shares down about 4% in Paris trading, as investors recalibrated expectations for one of the company’s closely watched late-stage pipeline assets. [1]
For U.S. investors watching the ADR, Sanofi (NASDAQ: SNY) traded around $48.68 at the latest timestamp available from market data in this session (10:15 UTC), modestly lower on the day.
Below is what happened, why it matters for Sanofi stock (SAN.PA / SNY), and how today’s news feeds into the latest analyst forecasts and consensus estimates.
What’s moving Sanofi stock today
Sanofi’s update centered on tolebrutinib, an investigational oral Bruton’s tyrosine kinase (BTK) inhibitor designed to target neuroinflammation, a major driver of disability progression in MS. [2]
Two items landed at once:
- A delay in the expected U.S. FDA regulatory decision timeline for non-relapsing secondary progressive multiple sclerosis (nrSPMS). [3]
- A Phase 3 miss in primary progressive multiple sclerosis (PPMS) (PERSEUS study), prompting Sanofi to say it will not pursue regulatory registration in PPMS. [4]
Markets tend to dislike “double headlines” like this—not because any one data point necessarily kills a program, but because it increases uncertainty around timelines, peak sales assumptions, and (sometimes) accounting values attached to pipeline assets.
The FDA delay: nrSPMS decision now expected after Dec. 28, with guidance by end of Q1 2026
Sanofi said its discussions with the U.S. Food and Drug Administration indicate the regulatory decision for tolebrutinib in nrSPMS is anticipated to extend beyond the previously communicated target action date of December 28, 2025. The company said it expects further guidance from the FDA by the end of the first quarter of 2026. [5]
Sanofi also emphasized it submitted an expanded access protocol for eligible patients (outside clinical trials) following an FDA request—language the market often reads as a signal that the agency is still actively working through the file rather than walking away from it. [6]
The Phase 3 miss: PERSEUS in PPMS fails its primary endpoint
In a separate update, Sanofi reported that the PERSEUS Phase 3 study in primary progressive MS did not meet its primary endpoint (a disability progression measure versus placebo). Based on the results, Sanofi said it will not pursue regulatory registration for PPMS. [7]
Sanofi said the safety profile in PERSEUS was consistent with prior studies; however, Investing.com’s report also noted that drug-induced liver injury remains an identified risk requiring strict monitoring—a reminder that this program has carried both efficacy and safety scrutiny throughout its development arc. [8]
Why investors care: progressive MS is a high-value market, and timelines matter as much as data
Progressive MS—particularly forms less driven by acute relapses—has historically been hard to treat, and effective therapies can command significant commercial value. That’s part of why tolebrutinib has been so closely watched.
The market reaction reflects a few practical realities:
- PPMS is a meaningful segment (Investing.com noted PPMS represents about 10% of the overall MS population), but Sanofi has repeatedly framed nrSPMS as the larger commercial opportunity. [9]
- A regulatory delay can compress commercial ramp time, shift revenue between fiscal years, and increase the odds that competitive readouts arrive first. [10]
- Sanofi has already said tolebrutinib is under regulatory review in the EU and received provisional approval in the United Arab Emirates (for nrSPMS), so the program’s outlook is not solely U.S.-dependent—but the FDA path still heavily influences global sentiment and valuation models. [11]
Analyst and market commentary: “negative surprise” vs “premature to write it off”
Reuters reported that Jefferies analysts described the PPMS trial failure as an unexpected negative, but still pointed to nrSPMS as the bigger commercial prize. [12]
Investing.com carried a longer excerpt of that stance: Jefferies characterized the PPMS result as a “negative surprise,” described the nrSPMS delay as “confusing but explainable,” and argued that an expanded access request may suggest the FDA is comfortable with the current risk/benefit profile (with monitoring safeguards). [13]
That split—near-term disappointment versus longer-term optionality—is common in biotech-style catalysts inside large pharma stocks. The stock move often becomes a referendum on whether investors believe management can still translate the remaining indications into a durable growth driver.
Sanofi says 2025 guidance unchanged—but an impairment test is coming
Sanofi stated its 2025 guidance remains unchanged even after the PPMS miss and the nrSPMS delay. [14]
But the company also flagged a key financial-process detail: it will conduct an impairment test on the intangible asset value of tolebrutinib, with results expected alongside Q4 and full-year 2025 financial results in January 2026. Sanofi said this will have no impact on business net income or business EPS and does not change 2025 guidance. [15]
Investors often watch impairment language closely because it can hint at management’s updated probability-weighted outlook for future cash flows, even when “core/business” metrics are protected.
Sanofi stock forecast: what consensus estimates and price targets imply right now
It’s important to separate company guidance (what management commits to) from street consensus (what analysts collectively model). On December 15, several widely followed consensus compilers still show meaningful implied upside—though those targets can change quickly after major pipeline news.
European listing (SAN.PA): MarketScreener consensus
MarketScreener’s analyst consensus page for Sanofi (Euronext Paris: SAN) shows:
- Mean consensus: BUY
- Number of analysts: 22
- Last close: €83.32
- Average target price: €105.20
- Implied upside: +26.26% (based on those figures) [16]
Sanofi’s own investor site links to Vara Research consensus (estimates as of Dec. 2, 2025)
Sanofi lists its analyst coverage and provides a link-out to Vara Research for compiled consensus estimates (with explicit disclaimers that the company does not endorse or verify the figures). [17]
Vara’s “Business P&L” consensus snapshot (dated 2025-12-02) includes, among other metrics:
- Net sales (FY 2025E) consensus mean: €43,479 million
- Net sales (FY 2026E) consensus mean: €46,208 million
- Business EPS (FY 2025E) consensus mean: €7.75
- Business EPS (FY 2026E) consensus mean: €8.41 [18]
These are not guarantees—just a structured window into what analysts were modeling heading into today’s MS update.
U.S. ADR (SNY): MarketBeat consensus target
For the U.S.-listed ADR, MarketBeat’s compilation (page updated 12/15/2025) reports:
- Consensus rating: “Moderate Buy” (12 analyst ratings)
- Consensus price target: $62.67
- Implied upside: 28.73% from a referenced price of $48.68 [19]
Different platforms often show different targets due to coverage lists, currency, timing, and methodology—so it’s less about “the one true number” and more about whether targets trend down after new information.
Key dates and catalysts to watch after December 15
Sanofi investors now have a tidy checklist of near-term milestones:
- By end of Q1 2026: Sanofi expects further FDA guidance on the nrSPMS application timeline. [20]
- January 2026: Sanofi plans to report Q4 and full-year 2025 results, alongside the announced tolebrutinib impairment test outcome. [21]
- December 16, 2025: Sanofi is hosting a year-end late-stage pipeline review led by R&D management—an event that could shape narrative around what replaces (or reinforces) tolebrutinib’s role in the growth story. [22]
The broader regulatory backdrop: Beyfortus faces renewed FDA scrutiny (earlier in December)
While today’s move is directly tied to tolebrutinib, Sanofi has also been navigating a noisier regulatory climate in the U.S. Reuters reported on December 9, 2025 that U.S. regulators told senior executives at Merck, Sanofi, and AstraZeneca their infant RSV preventive therapies—including Beyfortus (Sanofi/AstraZeneca)—would face fresh safety scrutiny, following concerns raised by vaccine skeptics. [23]
This RSV scrutiny is a separate story from MS, but it matters for the stock because it touches a marketed product with real revenue and public-health visibility—exactly the kind of issue that can add “headline risk” even when underlying clinical data remain supportive. [24]
Bottom line for Sanofi stock
Sanofi’s December 15 update is a classic large-pharma market moment: a high-profile pipeline asset takes a hit, timelines stretch, and investors immediately ask what that does to the next 12–24 months of growth expectations.
What’s clearer after today:
- PPMS is off the table for tolebrutinib registration, based on PERSEUS. [25]
- The nrSPMS decision is delayed beyond Dec. 28, with next FDA guidance expected by end-Q1 2026. [26]
- Street models still broadly lean positive on the stock (consensus “BUY”/“Moderate Buy” across major compilers), but those targets may be revised as analysts digest the news and management updates. [27]
As always with pharma equities, the “stock story” isn’t a single drug—it’s whether the company can keep converting science into approvals on schedule. Today, the schedule slipped.
References
1. www.reuters.com, 2. www.investing.com, 3. www.sanofi.com, 4. www.sanofi.com, 5. www.sanofi.com, 6. www.sanofi.com, 7. www.sanofi.com, 8. www.investing.com, 9. www.investing.com, 10. www.reuters.com, 11. www.reuters.com, 12. www.reuters.com, 13. www.investing.com, 14. www.marketscreener.com, 15. www.investing.com, 16. www.marketscreener.com, 17. www.sanofi.com, 18. vara-services.com, 19. www.marketbeat.com, 20. www.sanofi.com, 21. www.investing.com, 22. www.sanofi.com, 23. www.reuters.com, 24. www.reuters.com, 25. www.sanofi.com, 26. www.sanofi.com, 27. www.marketscreener.com
