Argenx will acquire Forte Biosciences, the developer of an autoimmune disease drug that’s shown early promise, in a deal worth up to $2.2 billion.
The Netherlands-based company said Monday it will secure ownership of Forte Biosciences by paying $77 per share in cash, a roughly 41% premium to the biotechnology firm’s closing price Friday. The deal, which should close in the third quarter, revolves around an experimental drug called FB102 with the potential to treat many immunological conditions, the company said.
“The acquisition of Forte Biosciences builds on the strength of that foundation and advances our ambition to be the leading immunology innovator of the future,” said Argenx CEO Karen Massey, in a statement. “The addition of FB102 to our portfolio aligns perfectly with the Argenx playbook: compelling biology, strong clinical validation and broad potential to address patient need.”
Argenx in recent years has emerged as one of biopharmaceutical sector’s most valuable companies, sporting a market capitalization of more than $56 billion. Argenx achieved that worth through the successful launch of its immune drug Vyvgart, which was first approved for myasthenia gravis in 2021 and gained an expanded approval in another autoimmune condition in 2024. The drug generated more than $4 billion in 2025 and is on track to eclipse that mark in 2026, with sales reaching close to $2.9 billion between January and June.
Argenx is now looking to other ways to grow its pipeline and, like many of its peers in a particularly active year, has turned to dealmaking.
The buyout announced Monday hands Argenx FB102. The drug is an antibody aimed at a “CD122,” a protein known that regulates multiple types of immune cells. That approach, which Argenx referred to as “differentiated,” has drawn the interest of multiple other companies for its potential to affect many conditions. Teva Pharmaceutical and Fast Tracks Biotherapeutics, for example, have similar drugs in clinical development. Argenx itself previously showed interest in this space, having participated in an April stock offering for Forte.
So far, Forte has accumulated positive, early-stage data in celiac disease and the skin condition vitiligo. Phase 2 data are expected later this year. Argenx believes the drug has potential elsewhere, too, such as alopecia areata — where Phase 1b data should also come in 2026 — and other autoimmune diseases.
To Luca Issi, an RBC Capital Markets analyst, the acquisition is “not surprising” given Argenx already built an equity stake in Forte. Nonetheless, Issi expressed surprise that Argenx didn’t wait for more data “before pulling the trigger on a relatively large transaction,” he wrote.
In a separate note, Leerink Partners analyst Thomas Smith referred to FB102 as a possible “pipeline-in-a-product” candidate that caters to Argenx’s strengths. The company is “well-suited to prosecute FB102 across numerous settings with attractive” commercial markets in autoimmune diseases, he wrote to clients Monday.
