How Abivax Went From Biotech Nobody To M&A Bullseye After A Single Blockbuster Readout This Year

A 1,900% rally, Phase 3 wins, and takeover chatter around Eli Lilly have transformed Abivax from a risky clinical bet into a strategic asset with real optionality.

• With Abivax now trading as a strategic asset rather than a pure clinical story, takeover interest from a deep-pocketed pharma player introduces a potential valuation floor.
• At roughly an $11 billion market cap, the stock is priced with strong odds of UC success and meaningful commercialization.
• There is still room for upside if Crohn’s disease data validate a broader, multi-indication franchise.

French clinical-stage biotech Abivax (ABVX) had an uneventful Nasdaq debut in October 2023 and spent much of its early public life flying under the radar. That changed abruptly this year after a single clinical data readout flipped the narrative — a familiar inflection point in biotech investing. Abivax’s stock is up nearly 1,900% year-to-date, making it the best-performing biotech stock on U.S. exchanges.

Adding fuel to the mid-year momentum, Eli Lilly (LLY) has emerged as a potential suitor, with market chatter suggesting the pharma giant is circling the smaller biotech. French media outlet La Lettre reported earlier this week that a delegation of Lilly executives met with the French Treasury and submitted an acquisition proposal for Abivax.

How does this shift the investment thesis around this smaller name? What was once a high-beta, data-driven clinical bet increasingly looks like a strategic M&A optionality trade, with a potential floor under the stock—at least in the near term.

Source: Koyfin<

From Clinical Breakout to Strategic Asset

For all the hype around the name, Abivax is still more or less a one-trick pony. Its lone pipeline asset and lead candidate, Obefazimod, is an immunomodulator that is being evaluated for multiple indications. The indication that is most developed is moderately to severely active ulcerative colitis (UC). 

Obefazimod acts by enhancing the expression of microRNA-124 (miR-124), a natural regulator of the inflammatory response. Inflammatory Bowel Disease (IBD), a broader term used to refer to chronic conditions such as UC and Crohn’s disease, is an autoimmune response. The immune system mistakenly attacks the gut, causing inflammation and damage to the digestive tract, leading to symptoms such as diarrhea, abdominal pain, weight loss and fatigue. 

UC affects the large intestine and rectum, causing ulcers on the inner lining, and Crohn’s disease can affect any part of the gastrointestinal tract and inflames the entire bowel wall. 

Is the condition such a big opportunity? By Abivax’s own account, it seems so. In a corporate presentation, the company said, citing Evaluate data, that IBD prevalence was 3.6 million in the G7 nations in 2024, with roughly 64% in the U.S. The prevalence is expected to grow at a modest 4% pace over the next six years. Worldwide IBD drug sales in 2024 are estimated at $23.7 billion, with 70% from the U.S.

Worldwide IBD Sales 

Source: Abivax<

The current treatment options include:

-Interleukin-23 selective inhibitors (block the action of pro-inflammatory cytokine protein interleukin-23)

-Sphingosine 1-phosphate (S1P) modulators such as ozanimod and etrasimod (target proteins linked to inflammation on immune cells and stop them from leaving the lymph nodes)

-Janus Kinase (JAK) inhibitors (stop several types of pro-inflammatory cytokines from forming)

Abivax projects Obefazimod as a differentiated treatment option compared to existing therapies, by enhancing the expression of microRNA-124, a natural regulator of the inflammatory response. The mode of administration is also convenient: an oral once-daily pill with a favorable long-term safety profile.

Wall Street Analysts’ Optimism Abounds

Following topline data from two Phase 3 studies showing the candidate met the primary and secondary endpoints, Abivax stock received love from several Wall Street firms, with Morgan Stanley upgrading the stock to an ‘Overweight,’ according to the Fly. 

The pooled placebo-adjusted clinical remission for the 50mg dose of 16.4% came in above the roughly 15% bar that Morgan Stanley analysts estimated based on their conversations with investors and experts. The analyst also expected improved odds of success across UC and Crohn's.  Guggenheim analysts estimated Obefazimod’s value at $7 billion to $10 billion.

Piper Sandler analysts said following the Phase 3 data, they have layered in revenue in early-line UC. This doubles its U.S. UC estimate to 2.66 billion euros ($3.14 billion) in 2035, suggesting there could be significant upside to the stock ahead of key data events.

Abivax presented the results of the two late-stage studies at the United European Gastroenterology (UEG) Meeting in Berlin in early October. Citizen JMP analysts, who upped their price target ahead of the event, said the data reinforce Obefazimod’s efficacy and increase conviction in its multi-billion-dollar sales potential. Guggenheim named Abivax as a “Best Idea” and upped its price target to $150. 

Last month, Wolfe Research initiated coverage of the stock with an ‘Outperform’ rating and a $176 price target. The firm based its optimistic assessment on its belief that the company’s odds of success in Crohn’s disease may be higher than those of UC. Crohn’s readout would be a better catalyst in 2026, it added.

According to Koyfin, the average analyst price target for Abivax stock is $138.35, implying a 22% downside from current levels. Of the five analysts covering the stock, four have either a ‘Buy’ or a ‘Strong Buy’ rating, and one remains on the sidelines.

Retail Jump Onto Bullish Bandwagon

The Abivax stock stream on Stocktwits has attracted a large following, with the watcher count jumping over 5,500% in the past year. The 30-day message volume is up 2,100%. 

Retail sentiment toward the stock was ‘extremely bullish’ as of early Wednesday, and it has mainly remained upbeat throughout the year. A bullish watcher has already set his sights on the $230 level for a stock that ended Tuesday’s session at $138.35.

Key Catalysts Investors Are Watching

Fresh off its addition to the Nasdaq Biotechnology Index, Abivax is entering a catalyst-rich phase. The topline results from an ongoing 44-week maintenance trial, dubbed ABTECT-107, are expected to be read out in the second quarter of 2026. The company also plans to release topline data from the Phase 2 Crohn’s Disease study in the second half of next year.

Why Lilly Might Be Interested

Obefazumod could be a better fit in Lilly’s immunology franchise, which includes Omvoh, an IL-23 inhibitor, used as a second-line treatment for adults with moderately to severely active UC and Crohn’s disease. It is administered as an IV infusion. Lilly also acquired Morphic Pharma, thereby adding an oral integrin blocker for UC.

Abivax’s current market valuation is roughly $11 billion. The company’s cash position as of Sept. 2025 is 589.7 million euros, and the company said it has a cash runway into the fourth quarter of 2027. 

Whether that Lilly deal materializes or not, Abivax enters 2026 with elevated expectations, higher stakes, and far more eyes on the name than ever before.

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