Danish biotechnology company Genmab (Nasdaq: GMAB) has agreed to acquire Dutch oncology firm Merus (Nasdaq: MRUS) in an all-cash transaction valued at roughly $8 billion, a move that significantly expands Genmab’s late-stage pipeline and accelerates its push toward a fully owned operating model.
Under the terms of the deal, Genmab will pay $97.00 per share for all outstanding common shares of Merus, representing a premium of more than 40% over Merus’ most recent closing price. The boards of both companies have unanimously approved the transaction, which is expected to close by the first quarter of 2026 pending regulatory and shareholder approvals.
The acquisition brings Merus’ lead asset, petosemtamab, into Genmab’s pipeline. The bispecific antibody therapy, currently in Phase 3 clinical trials, has received two Breakthrough Therapy Designations from the U.S. Food and Drug Administration for treatment of head and neck cancers. Recent Phase 2 data presented at the 2025 ASCO meeting indicated promising efficacy, with outcomes surpassing standard of care benchmarks.
The addition of petosemtamab is expected to bolster Genmab’s transition to a fully owned model, reducing reliance on partnerships and collaborations. By 2027, Genmab anticipates four proprietary programs reaching the commercial stage, positioning the company for multiple new product launches within oncology.
Petosemtamab’s potential launch as early as 2027 could deliver significant commercial impact, with projections suggesting annual sales of $1 billion by 2029 and the possibility of multi-billion-dollar revenues in the longer term. Genmab expects the acquisition to become accretive to EBITDA before the end of the decade.
The $8 billion consideration will be financed through a combination of cash on hand and approximately $5.5 billion in debt, backed by commitments from Morgan Stanley Senior Funding. Genmab stated it remains committed to deleveraging, with a target of reducing gross leverage below three times within two years of closing.
A tender offer for Merus shares will launch in the coming weeks. If successful, the transaction will result in Merus becoming a wholly owned subsidiary of Genmab. Shareholders who do not tender their shares are expected to receive equivalent value through statutory buy-out proceedings in the Netherlands.
The deal highlights the intense competition among biotech companies to secure late-stage oncology assets with strong regulatory momentum. By integrating Merus’ multispecific antibody expertise, Genmab gains not only a promising drug candidate but also a platform that complements its own antibody development technologies.
For Merus, the acquisition provides the scale and resources of a global biotechnology leader to advance petosemtamab through late-stage development, regulatory review, and potential commercialization.
With a strong balance sheet, an expanded pipeline, and an emphasis on proprietary innovation, Genmab is positioning itself to compete more directly with larger global oncology players in the second half of the decade.
