argenx to buy Forte Biosciences for $2.2 billion in autoimmune push

argenx is paying $77 a share in cash for Forte Biosciences, a 86% premium to the stock's volume-weighted average price since the company reported positive Phase 1b vitiligo data on July 9.

Belgian-Dutch immunology company argenx (ARGX: Euronext & Nasdaq) agreed to acquire Forte Biosciences (FBRX: Nasdaq) for $2.2 billion in an all-cash deal, adding a first-in-class anti-CD122 antibody with clinical proof-of-concept in two autoimmune indications. The transaction, announced Monday, builds on argenx's prior strategic investment in the Dallas-based biotech.

"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," said Karen Massey, chief executive officer of argenx, in a statement. She said the acquisition advances the company's Vision 2030 strategy to become "the leading immunology innovator of the future."

Forte's lead program, FB102, targets pathogenic T-cell and NK-cell activity through CD122 biology — a mechanism distinct from argenx's existing portfolio of antibody-based medicines including efgartigimod, empasiprubart and adimanebart. The drug has demonstrated statistically significant treatment benefit in a Phase 1b vitiligo study and positive Phase 1b data in celiac disease reported last year, with Phase 2 celiac results expected in the second half of 2026. Beyond those indications, FB102 has potential in alopecia areata and additional autoimmune conditions, giving it what argenx described as a pipeline-in-a-product profile.

The $2.2 billion price tag reflects the value argenx places on accessing novel biology in a therapeutic area where innovation has been limited. Vitiligo affects roughly 1% of the global population, while celiac disease impacts about 1.4% of people worldwide, according to published prevalence estimates — representing large addressable markets with few approved treatment options. The deal is expected to close in the third quarter of 2026, subject to regulatory approvals including the Hart-Scott-Rodino waiting period and tender of a majority of Forte's outstanding shares.

Deal Structure and Advisors

The transaction will be funded entirely from argenx's cash on hand and is not subject to a financing condition. Goldman Sachs International served as exclusive financial advisor to argenx, with Freshfields LLP providing legal counsel. Guggenheim Securities advised Forte Biosciences, with Wilson Sonsini Goodrich & Rosati as legal advisor.

The boards of both companies have approved the transaction. argenx will host an investor conference call at 8:00 a.m. ET Monday to discuss the deal.

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