Argenx Strikes $2.3 Billion Deal to Acquire Potential Successor to Vyvgart

Argenx will acquire Forte Biosciences for 3.3 trillion won to secure a next-generation autoimmune disease drug candidate.

According to BioPharma Dive on July 27 (local time), Argenx agreed to acquire Forte shares for 115,500 won ($77) per share. That price represents a premium of approximately 41% over Friday’s closing price. The acquisition is expected to be completed in the third quarter of this year.

The centerpiece of the acquisition is the drug candidate FB102. FB102 is an antibody drug that targets CD122, a protein that regulates several types of immune cells. Argenx described the approach as a “differentiated” mechanism that could be applied to a range of immune diseases.

Teva Pharmaceuticals and Fast Track Biosciences, among others, are also developing similar CD122-targeted drugs. Argenx signaled its interest in the field by participating in Forte’s paid-in capital increase in April.

Forte has obtained positive early clinical data for FB102 in celiac disease and vitiligo. Phase 2 results are expected later this year, while Phase 1b data in alopecia areata are also scheduled for release within the year.

Argenx has grown into a company with a market capitalization exceeding 84 trillion won ($56 billion) on the success of its autoimmune disease treatment Vyvgart. Vyvgart generated more than 6 trillion won ($4 billion) in revenue in 2025 and recorded approximately 4.35 trillion won in revenue in the first half of this year alone.

Argenx CEO Karen Massey said in a statement, “The acquisition of Forte will advance our goal of becoming a leading innovator in the immunology of the future.”

Luca Ish, an analyst at RBC Capital Markets, said, “It is not surprising that Argenx already owns a stake in Forte,” but added that “it is unexpected that the company did not wait for more data before pursuing a relatively large transaction.”

Thomas Smith, an analyst at Relink Partners, called FB102 a “pipeline in a product” candidate and said, “Argenx has the capabilities to successfully develop FB102 in the attractive autoimmune disease market.”