Genmab

Genmab A/S is a Danish biotechnology company focused on discovering, developing and commercializing antibody-based medicines. Founded in Copenhagen in February 1999 as a European spin-off associated with the American biotechnology company Medarex, Genmab initially built its business around fully human monoclonal antibodies and partnerships with larger pharmaceutical companies. Its core objective has been to use antibody biology and proprietary platforms to address cancer, immune-mediated disease and other conditions where selective biological targeting can provide therapeutic benefit. The company’s early technology base included a license to Medarex’s HuMab-Mouse platform, which used transgenic mice to generate fully human antibodies. This approach was intended to reduce the immunogenicity and development complexity associated with antibodies containing non-human protein sequences. Genmab later developed proprietary antibody technologies, including UniBody, a smaller antibody format derived from modified human IgG4. UniBody was designed to bind a single target site and to distribute differently from conventional full-size antibodies. Genmab subsequently expanded its technology portfolio into bispecific antibodies and other formats capable of directing immune cells toward diseased cells. Genmab became a listed biotechnology company in 2000 and raised further capital through a 2006 offering. During its early development, it entered licensing and collaboration agreements with companies including Amgen, GlaxoSmithKline, Roche, Johnson & Johnson/Janssen, AbbVie, Novartis and other pharmaceutical partners. These arrangements allowed Genmab to use partner resources for clinical development, manufacturing and global commercialization while retaining economic interests in products derived from its antibody platforms. The company’s first marketed medicine was Arzerra, or ofatumumab, which reached the United States market in 2009 for previously treated chronic lymphocytic leukemia. Although the commercial and strategic history of ofatumumab was complicated by changing partner priorities and Genmab’s own financial pressures, the program established the company as a clinically productive antibody developer. Ofatumumab was later developed by Novartis as Kesimpta for relapsing forms of multiple sclerosis. Genmab also pursued an in-house manufacturing strategy in the late 2000s, including the acquisition of a large antibody manufacturing facility in Minnesota. The facility proved difficult to operate profitably during the global financial crisis and amid changes in oncology partnership strategy. Genmab ultimately sold the plant and reorganized, then moved toward outsourcing manufacturing and much of clinical execution. This shift helped the company concentrate capital and management attention on discovery, translational science, clinical development and strategic partnerships. Its later product portfolio has included antibodies and antibody-drug conjugates such as Darzalex and Darzalex Faspro, epcoritamab, tisotumab vedotin, amivantamab, talquetamab, teclistamab, teprotumumab and Kesimpta. Several are owned or commercialized by partners, while Genmab has retained rights or co-development interests in selected products. Darzalex, developed with Janssen, became one of the most important commercial applications of Genmab’s antibody expertise in multiple myeloma. Epcoritamab, marketed as Epkinly in the United States and Tepkinly in some other markets with AbbVie, extended Genmab’s role in T-cell-engaging bispecific medicines for B-cell lymphomas. Genmab operates internationally through entities and facilities in the Netherlands, United States, Japan, Germany and China, in addition to Denmark. Its research and development presence in Utrecht has been an important part of its European scientific infrastructure. The company’s current business model combines proprietary discovery platforms, internally managed development programs, and collabor…

Genmab was established in Copenhagen in February 1999 with seed backing associated with BankInvest Biomedical and a scientific and technological relationship to Medarex. The founding organization was created to develop fully human antibodies against serious diseases, building on Medarex’s HuMab-Mouse technology. This platform used genetically modified mice to generate antibodies with human protein sequences, potentially reducing the need for later humanization and lowering the risk of immune reactions compared with antibodies containing animal-derived sequences. The company pursued a partnership-oriented model from the beginning. In 1999 it entered a sublicensing arrangement with Amgen involving antibodies directed at interleukin-15, later replaced by a direct license arrangement. Genmab also developed relationships with Roche and other pharmaceutical companies while expanding its own research capabilities. It completed an initial public offering on the Copenhagen Stock Exchange in October 2000 and raised additional capital in a public offering in January 2006. These financings supported the development of an antibody pipeline, although the economics of biotechnology development exposed the company to substantial clinical, manufacturing and partnering risks. Genmab’s technology portfolio broadened beyond the licensed HuMab platform. Its UniBody format was designed as a smaller antibody derived from modified IgG4. By removing the conventional antibody hinge structure, Genmab sought to create a compact molecule with single-site binding and different tissue-distribution characteristics. The company later advanced additional antibody formats, including bispecific molecules that can engage immune cells and tumor-associated targets simultaneously. This work became especially important to Genmab’s later oncology strategy. The company’s collaboration with GlaxoSmithKline, announced in December 2006, centered on ofatumumab. The antibody targeted CD20 and was developed for B-cell malignancies and immune-mediated diseases. Genmab’s first commercial product, Arzerra, was approved in the United States in 2009 for refractory chronic lymphocytic leukemia. The commercial history of the program was affected by GSK’s changing oncology priorities, disagreements concerning development milestones and Genmab’s financial position. The parties renegotiated their relationship in 2010, producing changes to payments, rights and future economics. Ofatumumab was subsequently developed by Novartis as Kesimpta for relapsing multiple sclerosis, giving the antibody a substantial later role in autoimmune medicine. Genmab attempted to bring manufacturing closer to the company by purchasing a large antibody production facility in Brooklyn Park, Minnesota, from PDL BioPharma in 2008. The plan included retaining the facility’s workforce and producing development-scale material. The effort coincided with the global financial crisis, partner changes and pressure on Genmab’s operating model. In late 2009 the company decided to sell the facility and reorganized, including a substantial workforce reduction. The site was eventually sold to Baxter International in 2013, after Genmab had written down the asset. The experience led to a durable strategic decision to outsource manufacturing and clinical-trial execution rather than operate a large internal manufacturing base. During the 2010s and 2020s, Genmab increasingly emphasized development through large pharmaceutical partnerships. Daratumumab, developed with Janssen and marketed as Darzalex and Darzalex Faspro, became a major treatment for multiple myeloma and was also used in light-chain amyloidosis. Other products incorporating Genmab research or technology included amivantamab, teprotumumab, tisotumab vedotin and ofatumumab. Genmab also advanced epcoritamab, a bispecific antibody developed with AbbVie and marketed as Epkinly or Tepkinly for relapsed or refractory B-cell lymphomas. Genmab expanded its international presence through subsidiaries and operations in the Netherlands, the United States, Japan, Germany and China. Its Utrecht research and development center became an important European base, with further expansion planned after the facility reached capacity. The company has remained headquartered in Copenhagen and listed in Denmark, while its American depositary receipts have traded in the United States. In 2024, Genmab announced the acquisition of ProfoundBio to strengthen its antibody-drug conjugate capabilities. In 2025, it announced a proposed acquisition of Merus, reflecting a strategy of supplementing internal antibody discovery with external technologies and late-stage development assets.

1. 2025Merus acquisition announced

   Genmab announced a proposed acquisition of Dutch biotechnology company Merus, subject to transaction conditions and approvals.

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2. 2024ProfoundBio acquisition announced

   Genmab announced a proposed acquisition intended to add antibody-drug conjugate capabilities and oncology assets.

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3. 2018New Utrecht research and development center opened

   Genmab replaced its initial Utrecht research location with a newer research and development facility.

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4. 2013Minnesota facility sold to Baxter

   The sale completed Genmab’s withdrawal from the large-scale in-house manufacturing strategy.

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5. 2010Jan Van de Winkel became chief executive officer

   Van de Winkel, a co-founder and long-serving scientific leader, succeeded Lisa Drakeman as CEO.

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6. 2009Arzerra became Genmab’s first marketed medicine

   Ofatumumab was introduced in the United States for a previously treated chronic lymphocytic leukemia population.

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7. 2008Acquisition of a Minnesota antibody manufacturing facility

   Genmab acquired a large manufacturing site from PDL BioPharma in an effort to build internal production capacity.

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8. 2006Ofatumumab partnership with GlaxoSmithKline

   Genmab granted GSK development and commercialization rights to ofatumumab across several oncology and immune-disease indications.

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9. 2005Genmab received the James D. Watson Helix Award

   The award was presented by the Biotechnology Industry Organization and the Long Island Life Sciences Initiative.

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10. 2001Genmab and Medarex renewed their development relationship

    The companies entered a drug-development partnership that highlighted Genmab’s need to strengthen manufacturing and clinical-development capabilities.

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11. 2000Initial public offering

    Genmab became publicly listed on the Copenhagen Stock Exchange and raised capital to support antibody research and development.

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12. 1999Genmab was founded in Copenhagen

    The company was established as a European biotechnology spin-off associated with Medarex, with seed backing linked to BankInvest Biomedical.

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A science-led antibody company positioned around proprietary antibody platforms, differentiated formats and partnership-based global commercialization, with a primary focus on oncology and hematologic disease.

• Arzerra / ofatumumabFully human monoclonal antibody2009

  Ofatumumab is an anti-CD20 antibody first commercialized as Arzerra for certain previously treated patients with chronic lymphocytic leukemia. Genmab developed the molecule with pharmaceutical partners, and later development by Novartis produced Kesimpta, an injectable treatment for relapsing forms of multiple sclerosis.

• Darzalex / Darzalex Faspro (daratumumab)Monoclonal antibody2015

  Daratumumab targets CD38 and is used in multiple myeloma across several treatment settings, both alone and in combination regimens. The product is marketed in intravenous and subcutaneous formulations, the latter combining daratumumab with hyaluronidase. It is also used in newly diagnosed light-chain amyloidosis.

• Epkinly / Tepkinly (epcoritamab)Bispecific antibody2023

  Epcoritamab is a CD3-by-CD20 bispecific antibody designed to bring T cells into contact with malignant B cells. It is used for selected adults with relapsed or refractory B-cell lymphomas, including diffuse large B-cell lymphoma and follicular lymphoma, and is commercialized with AbbVie.

• Tivdak (tisotumab vedotin)Antibody-drug conjugate2021

  Tisotumab vedotin is an antibody-drug conjugate directed at tissue factor and linked to a cytotoxic payload. It is approved in the United States for previously treated recurrent or metastatic cervical cancer and has also been studied in additional solid tumors.

• Rybrevant (amivantamab)Bispecific antibody2021

  Amivantamab is an EGFR-MET-directed antibody used in selected non-small-cell lung cancer settings, including tumors with EGFR exon 20 insertion mutations. It is marketed by Janssen and has been evaluated in combination regimens and additional gastrointestinal and thoracic cancer indications.

• Tecvayli (teclistamab)Bispecific antibody2022

  Teclistamab is a BCMA-by-CD3 bispecific antibody that directs T cells toward BCMA-expressing myeloma cells. It is used for adults with relapsed or refractory multiple myeloma after specified prior treatments and is marketed by Janssen.

• Talvey (talquetamab)Bispecific antibody2023

  Talquetamab is a GPRC5D-by-CD3 bispecific antibody for selected patients with relapsed or refractory multiple myeloma. Its mechanism recruits T cells to malignant plasma cells expressing GPRC5D, and the medicine is commercialized by Janssen.

• Tepezza (teprotumumab)Monoclonal antibody2020

  Teprotumumab targets the insulin-like growth factor 1 receptor and is used for thyroid eye disease. The program illustrates Genmab’s antibody contribution beyond oncology, with commercialization handled by a partner.

• 2025Proposed acquisition of MerusM&A

  Genmab sought to add Merus’s late-stage oncology pipeline and bispecific antibody capabilities.

  What changed. Genmab announced a proposed acquisition of Merus N.V.

  Aftermath. The proposal was positioned as a major expansion of Genmab’s oncology portfolio, subject to transaction conditions and approvals.

  Reported proposed transaction value. Approximately US$8 billion (2025)

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• 2024Proposed acquisition of ProfoundBioM&A

  Genmab sought to expand its oncology platform and antibody-drug conjugate capabilities.

  What changed. The company announced an agreement to acquire ProfoundBio.

  Aftermath. The transaction was intended to broaden Genmab’s discovery and development capabilities in antibody-drug conjugates.

  Announced transaction value. Approximately US$1.8 billion (2024)

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• 2013Genmab adopted an outsourced operating modelStrategy

  The company’s attempt to operate a major internal manufacturing facility created substantial financial and operational burdens.

  What changed. After selling the Minnesota site, Genmab chose to outsource manufacturing and clinical-trial conduct and focus on antibody discovery and development.

  Aftermath. The model became a foundation for Genmab’s later partnership-led growth and reduced the need for large internal production infrastructure.

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• 2010Genmab and GSK renegotiated the ofatumumab relationshipStrategy

  GSK’s changing oncology priorities, disagreements over milestones and Genmab’s financial situation affected the original collaboration structure.

  What changed. The companies revised payments, rights and licensing economics, including an immediate payment and future concessions.

  Aftermath. The renegotiation reduced near-term pressure while leaving Genmab dependent on partnerships for broad development and commercialization.

  Immediate payment reported in the renegotiation. Approximately US$135 million (2010)

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• 2008Genmab pursued in-house antibody manufacturingStrategy

  The company sought greater control over production by acquiring a large Minnesota antibody manufacturing facility.

  What changed. Genmab purchased the facility from PDL BioPharma and initially planned to retain its workforce and produce development-scale batches.

  Aftermath. Financial pressure, the global recession and changing oncology-partner priorities made the strategy unsustainable. Genmab later sold the facility and moved toward outsourcing manufacturing.

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• 2025Genmab announced a proposed acquisition of Merus

  Genmab announced a proposed transaction to acquire Dutch biotechnology company Merus, subject to the applicable transaction conditions and approvals.

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• 2024Genmab announced the acquisition of ProfoundBio

  Genmab announced an agreement to acquire ProfoundBio, a biotechnology company developing antibody-drug conjugates and related oncology technologies.

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• 2013Genmab sold its Minnesota manufacturing facility

  After deciding to exit the in-house manufacturing strategy, Genmab’s former Brooklyn Park facility was sold to Baxter International.

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• 2009Arzerra reached the United States market

  Ofatumumab became Genmab’s first marketed product, initially indicated for certain patients with previously treated chronic lymphocytic leukemia.

  Product launch
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• 2006Genmab and GlaxoSmithKline entered a major ofatumumab development and commercialization agreement

  The agreement covered development and commercialization of ofatumumab across oncology, autoimmune and inflammatory indications and included an upfront license payment and an equity investment.

  M&AOther
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1. Genmab
2. Genmab official website
3. Genmab investor relations
4. Genmab management