Europe's best-performing blue-chip stocks in 2025 are expected to be bought by a larger peer, in a deal analysts say could be worth up to $23 billion.
Abivax, the clinical-stage French biotech company developing a treatment for ulcerative colitis and Crohn's disease, saw its shares soar 1,681% last year, far outpacing the Stoxx 600 Index second best performing stock, mining company fresnillowhich rose 453%.
Now, the big question for analysts appears to be when, not if, Abivax announces a deal.
The stock, which went public in 2015, largely ranged between 10 and 20 euros, but it wasn't until 10 years later that it really took off.. Shares surged 510% a day after Abivax reported results from a late-stage trial of an ulcerative colitis drug in July, beating even the most optimistic expectations. After these types of results, it could be a strategic acquisition for any large pharmaceutical company with an immunology and inflammation franchise.
Abivax's main (and only) active, obefazimod, was first developed as a treatment for HIV, but researchers discovered that its anti-inflammatory effect could affect other conditions such as inflammatory bowel disease (IBD) and began clinical trials.
The stock rose even further in December when rumors emerged that the world's most valuable pharmaceutical company, Eli Lilly, had its eyes set on acquiring Abivax. Both companies have repeatedly declined to comment on business development activities.
An imminent agreement?
Analysts say a deal could happen at any time.
Van Lanschot Kempen analyst Sebastiaan van der Schoot told CNBC that biotechs often “have a relatively small number of employees and don't have any experience in selling a drug,” which he called “a completely different ball game” to developing them.
“That's why pharmaceutical companies hire them to take advantage of their infrastructure,” he said.
The analyst added that he expected Abivax to trade between where it is now and where it was when rumors of a takeover first surfaced, through JP Morgan's annual healthcare conference on Monday. where companies often announce big deals.
Abivax shares rose in 2025, far outperforming its European peers.
This comes as big pharma has stepped up deals in recent months, as the sector faces a looming patent cliff where some of the world's best-selling drugs will lose exclusivity in the coming years.
Another factor making a deal more likely is Abivax CEO Marc de Garidel's reputation as a leader who can make deals happen. He previously led multi-billion dollar purchases of biotech companies from pharmaceutical companies such as AstraZeneca and Novo Nordisk.
When asked about a possible acquisition, de Garidel said on CNBC's “Europe Early Edition” in December that the company was always in “talks with big pharma” but that its role was to develop the best drug possible.
Abivax plans to file for regulatory approval in the U.S. by the end of 2026, with a possible launch planned for the third quarter of 2027, de Garidel said.
The company is well positioned to negotiate a favorable deal with a big pharma partner, said Stifel analyst Damien Choplain.
“Given the strength of the Phase III results and the paucity of comparable assets, we believe a transaction could be executed ahead of the expected maintenance data readout in the second quarter of 2026,” he said, referring to a second clinical trial of Obefazimod that tests its efficacy for 44 weeks instead of just eight weeks.
Choplain added that, historically, most transactions in the IBD space have occurred for drug candidates in earlier stages of development. “Abivax meets all the requirements for a strategic acquisition,” he said.
Based on comparable transactions and a peak sales estimate of €3 billion, Abivax's valuation could range between €12 billion and €20 billion ($14 billion to $23 billion), Choplain told CNBC.
Recent deals in the IBD space include Merck's acquisition of Prometheus for $10.8 billion; Roche acquisition of Telavant for $7.1 billion; and Eli Lilly buys Morphic for $3.2 billion. All of those deals were for assets at a stage of development prior to Abivax's obefazimod.
Potential best-in-class treatment
Jefferies analyst Roger Song, who doesn't cover Abivax per se but follows the IBD space closely from Boston, said investor optimism comes from both a potential multibillion-dollar market for IBD treatments and the drug candidate's novel way of addressing it through multiple pathways.
It's even considered the best potential treatment for ulcerative colitis, he told CNBC in December.
The July results from the Obefazimod trial surprised investors because many were unaware of the novel mechanism it uses, microRNA, Song said.
A late-stage maintenance test is expected in the second quarter of 2026.
Van der Schoot added that if Abivax is confident enough in those maintenance results, it can wait to be acquired after the trial is published, “because then they can ask for a higher price.”
