Genmab Announces Financial Results for the First Half of 2021

Genmab Announces Financial Results for the First Half of 2021

August 11, 2021; Copenhagen, Denmark;

Interim Report for the First Half of 2021

Genmab's antibody expertise and innovation were on display during the second quarter of 2021 with the U.S. FDA's acceptance for priority review of the BLA for tisotumab vedotin, which we are developing with Seagen, and with the approval of Janssen's RYBREVANT (amivantamab-vmjw), the first regulatory approval for a product created using Genmab's proprietary DuoBody technology platform. The majority of Genmab's clinical stage products are based on our DuoBody technology, and we hope that the approval of RYBREVANT is just the first validation of many of the potential for this technology to create effective treatments for patients with cancer, said Jan van de Winkel, Ph.D., Chief Executive Officer of Genmab.

Financial Performance First Half of 2021

Genmab is improving its 2021 financial guidance published on February 23, 2021, driven primarily by increased royalty revenue related to the net sales of DARZALEX.

Genmab Announces Financial Results for the First Half of 2021

Genmab will hold a conference call to discuss the results for the first half of 2021 today, Wednesday, August 11, at 6:00 pm CEST, 5:00 pm BST or 12:00 pm EDT. To join the call dial

+1 631 913 1422 (U.S. participants) or +44 3333 000804 (international participants) and provide conference code 78377092.

A live and archived webcast of the call and relevant slides will be available at www.genmab.com/investors.

Marisol Peron, Senior Vice President, Global Investor Relations and Communications

T: +1 609 524 0065; E: mmp@genmab.com

For Investor Relations:

Andrew Carlsen, Vice President, Head of Investor Relations

T: +45 3377 9558; E: acn@genmab.com

Interim Report for the First Half of 2021

Interim Report for the First Half of 2021

CONSOLIDATED KEY FIGURES

* Cash, cash equivalents, and marketable securities.

** Full-time equivalent

Interim Report for the First Half of 2021

Genmab is improving its 2021 financial guidance published on February 23, 2021, driven primarily by increased royalty revenue related to the net sales of DARZALEX.

Genmab expects its 2021 revenue to be in the range of DKK 7,300 7,900 million, an increase compared to previous guidance of DKK 6,800-7,500 million, driven primarily by the continued strong growth of DARZALEX net sales. Genmab's projected revenue for 2021 primarily consists of DARZALEX royalties of DKK 5,300 5,700 million. Such royalties are based on Genmab's revised estimate of DARZALEX 2021 net sales of USD 5.6 5.9 billion compared to Genmab's previous estimate of USD 5.2-5.6 billion. Since the second quarter of 2020, Janssen has reduced its royalty payments to Genmab by what it claims to be Genmab's share of Janssen's royalty payments to Halozyme in connection with subcutaneous (SC) sales. Given the ongoing arbitration, Genmab has reflected this as a reduction to estimated 2021 revenue. The remainder of Genmab's revenue consists of royalties from TEPEZZA and Kesimpta, reimbursement revenue, milestones for epcoritamab and daratumumab, and other milestones.

Genmab anticipates its 2021 operating expenses to be in the range of DKK 5,500 5,800 million, which is in line with previous guidance. Operating expenses continue to be driven by the advancement of Genmab's clinical programs, continued investment in research and development, as well as building Genmab's commercial organization and broader organizational infrastructure.

Genmab now expects its 2021 operating result to be in the range of DKK 1,500 2,400 million, an increase compared to previous guidance of DKK 1,000-2,000 million, driven primarily by the increase in royalty revenue related to the net sales of DARZALEX.

Outlook: Risks and Assumptions

In addition to factors already mentioned, the estimates above are subject to change due to numerous reasons, including but not limited to the achievement of certain milestones associated with Genmab's collaboration agreements; ongoing binding arbitration of two matters under Genmab's license agreement with Janssen relating to daratumumab; the timing and variation of development activities (including activities carried out by Genmab's collaboration partners) and related income and costs; DARZALEX, Kesimpta, TEPEZZA and RYBREVANT net sales and royalties paid to Genmab; and currency exchange rates (the 2021 guidance assumes a USD/DKK exchange rate of 6.0). The financial guidance assumes that no significant new agreements are entered into during the remainder of 2021 that could materially affect the results. Refer to the section Significant Risks and Uncertainties in this interim report. Additionally, the COVID-19 pandemic could potentially have a material adverse impact on Genmab's business and financial performance, including clinical trials, projected regulatory approval timelines, supply chain and revenues, and cause Genmab's actual results to differ materially from 2021 Guidance and Key 2021 Priorities in this interim report.

The global outbreak of COVID-19 may have long-term impacts on the development, regulatory approval and commercialization of Genmab's product candidates and on net sales of approved products created by

Interim Report for the First Half of 2021

Genmab and developed and marketed by Genmab's collaboration partners. The longer the pandemic continues, the more severe the impacts described below will be on Genmab's business. The extent, length and consequences of the pandemic are uncertain and impossible to predict. Genmab has established a COVID-19 response team, led by the CEO, that closely monitors the evolving situation, develops and implements precautionary measures to help limit the impact of COVID-19 at the workplace and on our communities, and ensures business continuity. Genmab is also actively monitoring the potential impact on Key 2021 Priorities and assessing the situation on an ongoing basis in close contact with clinical trial sites, physicians and contract research organizations (CROs) to evaluate the impact and challenges posed by the COVID-19 situation and manage them accordingly. The full extent and nature of the impact of the COVID-19 pandemic and related containment measures on Genmab's business and financial performance is uncertain as the situation continues to evolve. The factors discussed above, as well as other factors which are currently unforeseeable, may result in further and other unforeseen material adverse impacts on Genmab's business and financial performance, including on the net sales of DARZALEX, Kesimpta, TEPEZZA and RYBREVANT, by Genmab's partners and on Genmab's royalty and milestone revenue therefrom.

1. Co-development w/ Seagen Inc. (Seagen); 2. Co-development w/ AbbVie; 3. Co-development w/ BioNTech SE (BioNTech)

*Potential JNDA filing timeline postponed to include Phase 3 InnovaTV301 data

PRODUCT PIPELINE AND TECHNOLOGY PROGRESS FIRST HALF OF 2021

As of the end of the second quarter, Genmab's proprietary pipeline of product candidates, where we are responsible for at least 50% of development costs, consisted of eight clinical stage antibodies. In addition to our own pipeline, there are also 15 products in development by third-party companies, including four approved products, which incorporate Genmab technology and innovation. Beyond the antibodies in clinical development, our pipeline also includes around 20 in-house and partnered preclinical programs. An overview of the development status of each of our products is provided in the following sections. Detailed descriptions of dosing, efficacy and safety data from certain clinical trials have been disclosed in company announcements and media releases published via the Nasdaq Copenhagen stock exchange and may also be found in Genmab's filings with the U.S. Securities and Exchange Commission (SEC). Additional information is available on Genmab's website, www.genmab.com. The information accessible through our website is not part of and is not incorporated by reference herein.

Interim Report for the First Half of 2021

Genmab Proprietary Products1 in Development

1Product candidates where Genmab has 50% ownership. Certain products in co-development, partners as indicated

2Genmab is developing HexaBody-CD38 in an exclusive worldwide license and option agreement with Janssen

Tisotumab vedotin A Next Generation Therapeutic

Tisotumab vedotin is an ADC targeted to TF, a protein involved in tumor signaling and angiogenesis. It is composed of Genmab's fully human monoclonal antibody specific for tissue factor and Seagen's ADC technology that utilizes a protease-cleavable linker that covalently attaches the microtubule-disrupting agent monomethyl auristatin E (MMAE) to the antibody and releases it upon internalization, inducing target cell death. Based on its high expression on many solid tumors and its rapid internalization, TF is a suitable target for an ADC approach. Genmab used technology licensed from Medarex to generate the TF antibody forming part of tisotumab vedotin. Tisotumab vedotin is in clinical development for solid tumors. Tisotumab vedotin is being co-developed by Genmab and Seagen, under an agreement in which the companies share all costs and profits for the product on a 50:50 basis. Under a joint commercialization agreement, Genmab will co-

Interim Report for the First Half of 2021

promote tisotumab vedotin in the U.S. and lead commercial operational activities in Japan. Seagen will lead operational commercial activities in the U.S., Europe and China with a 50:50 cost and profit split in those markets. In any other markets, Seagen will commercialize tisotumab vedotin and Genmab will receive royalties based on a percentage of aggregate net sales ranging from the mid-teens to the mid-twenties. The companies will continue the practice of joint decision-making on the worldwide development and commercialization strategy for tisotumab vedotin.

Second Quarter 2021 Updates

First Quarter 2021 Updates

Epcoritamab (DuoBody-CD3xCD20) Potential Best-in-class Product Candidate

Epcoritamab is a proprietary bispecific antibody created using Genmab's DuoBody technology. Epcoritamab targets CD3, which is expressed on T-cells, and CD20, a clinically well-validated target on malignant B-cells. Genmab used technology licensed from Medarex to generate the CD20 antibody forming part of epcoritamab. Epcoritamab is being co-developed by Genmab and AbbVie. The first Phase 3 clinical study (NCT04628494) of epcoritamab in relapsed / refractory DLBCL is ongoing. In addition, Phase 1/2 clinical studies in B-cell non-Hodgkin lymphoma (B-NHL) including chronic lymphocytic leukemia (CLL) (NCT04623541) and in combination with standard of care therapies for B-NHL (NCT04663347) are ongoing.

Second Quarter 2021 Update

Interim Report for the First Half of 2021

First Quarter 2021 Updates

DuoBody-PD-L1x4-1BB (GEN1046) Bispecific Next Generation Checkpoint Immunotherapy

DuoBody-PD-L1x4-1BB (GEN1046) is a proprietary bispecific antibody, jointly owned by Genmab and BioNTech, created using Genmab's DuoBody technology. It is being co-developed by Genmab and BioNTech under an agreement in which the companies share all costs and profits for the product on a 50:50 basis. DuoBody-PD-L1x4-1BB targets PD-L1 and 4-1BB, selected to block inhibitory PD 1 / PD-L1 axis and simultaneously conditionally activate essential co-stimulatory activity via 4-1BB using inert DuoBody antibody format. Two clinical studies (NCT03917381, NCT04937153) in solid tumors are ongoing.

DuoBody-CD40x4-1BB (GEN1042) Potential First-in-Class Bispecific Agonistic Antibody

DuoBody-CD40x4-1BB (GEN1042) is a proprietary bispecific antibody, jointly owned by Genmab and BioNTech, created using Genmab's DuoBody technology. It is being co-developed by Genmab and BioNTech under an agreement in which the companies share all costs and profits for the product on a 50:50 basis. CD40 and 4-1BB were selected as targets to enhance both dendritic cells (DC) and antigen-dependent T-cell activation, using an inert DuoBody format. A Phase 1/2 clinical study (NCT04083599) of DuoBody-CD40x4-1BB in solid tumors is ongoing.

Second Quarter 2021 Update

HexaBody-DR5/DR5 (GEN1029) First HexaBody Program in Clinical Development

HexaBody-DR5/DR5 (GEN1029) is a product comprising a mixture of two non-competing HexaBody molecules that target two distinct epitopes on death receptor 5 (DR5), a cell surface receptor that mediates a process called programmed cell death. Increased expression of DR5 has been reported in several types of tumors. The product was created with our HexaBody technology and DR5 antibodies acquired from IDD Biotech. HexaBody-DR5/DR5 is fully owned by Genmab and a Phase 1/2 clinical study (NCT03576131) in solid tumors is ongoing.

Interim Report for the First Half of 2021

DuoHexaBody-CD37 (GEN3009) First DuoHexaBody Program in the Clinic

DuoHexaBody-CD37 (GEN3009) is a bispecific antibody created with Genmab's proprietary DuoHexaBody technology platform. The DuoHexaBody platform combines the dual targeting of our DuoBody technology with the enhanced potency of our HexaBody technology, creating bispecific antibodies with target-mediated enhanced hexamerization. DuoHexaBody-CD37 is being co-developed by Genmab and AbbVie on a 50:50 basis and a Phase 1/2 clinical study (NCT04358458) in hematologic malignancies is ongoing.

DuoBody-CD3x5T4 (GEN1044) Promising Novel Product Candidate

DuoBody-CD3x5T4 (GEN1044) is a bispecific antibody created with Genmab's proprietary DuoBody technology platform. DuoBody-CD3x5T4 induces T-cell mediated cytotoxicity of 5T4-positive cells by crosslinking CD3 on T cells with the tumor-associated antigen 5T4 on tumor cells. The broad expression of 5T4 across solid tumors and limited expression in normal cells makes DuoBody-CD3x5T4 a promising novel product candidate. DuoBody-CD3x5T4 is being co-developed by Genmab and AbbVie on a 50:50 basis and a Phase 1/2 clinical study (NCT04424641) in solid tumors is ongoing.

HexaBody-CD38 (GEN3014) Latest Proprietary Program in the Clinic

HexaBody-CD38 (GEN3014) is a human CD38 monoclonal antibody product incorporating our HexaBody technology. In preclinical models of hematological malignancies, as presented at ASH in December 2019, HexaBody-CD38 demonstrated enhanced CDC and had shown potent anti-tumor activity. In June 2019, Genmab entered into an exclusive worldwide license and option agreement with Janssen to develop and commercialize HexaBody-CD38. An Investigational New Drug (IND) application was submitted to the U.S. FDA for HexaBody-CD38 in October 2020 followed by Clinical Trial Application submissions in Europe in November 2020. The first patient was dosed in the first-in-human study (NCT0482479) in March 2021 and the study is ongoing.

First Quarter 2021 Update

Interim Report for the First Half of 2021

Products Created by Genmab or Incorporating Genmab's Innovation

In addition to Genmab's own pipeline of product candidates, our innovations are applied in the pipelines of other companies that are running clinical development programs with antibodies created by Genmab or created using Genmab's DuoBody bispecific antibody technology. Under these agreements, Genmab is entitled to certain potential milestones and royalties.

*See local country prescribing information for precise indications

DARZALEX (daratumumab)

Redefining the Treatment of Multiple Myeloma

DARZALEX (daratumumab) is a human monoclonal antibody that binds with high affinity to the CD38 molecule, which is highly expressed on the surface of multiple myeloma cells and is also expressed by AL amyloidosis plasma cells. Daratumumab triggers a person's own immune system to attack the cancer cells, resulting in rapid tumor cell death through multiple immune-mediated mechanisms of action and through

Interim Report for the First Half of 2021

immunomodulatory effects, in addition to direct tumor cell death, via apoptosis (programmed cell death). Genmab used technology licensed from Medarex to generate the CD38 antibody forming part of daratumumab. Daratumumab is being developed by Janssen under an exclusive worldwide license from Genmab to develop, manufacture and commercialize daratumumab. Under the terms of the agreement, Genmab is entitled to double digit royalties between 12% and 20%. Daratumumab (marketed as DARZALEX for intravenous administration and as DARZALEX FASPRO in the United States and as DARZALEX SC in Europe for SC administration) is approved in certain territories for the treatment of adult patients with certain multiple myeloma indications and is the only approved therapy in the U.S. and Europe for the treatment of adult patients with AL amyloidosis.

Please consult the full U.S. Prescribing Information and the full European Summary of Product Characteristics for DARZALEX (daratumumab) and the full U.S. Prescribing Information for DARZALEX FASPRO (daratumumab and hyaluronidase-fihj) for all of the labeled safety information.

Second Quarter 2021 Updates

First Quarter 2021 Update

Kesimpta (ofatumumab) Approved in RMS in the U.S.

Ofatumumab is a human monoclonal antibody that targets an epitope on the CD20 molecule encompassing parts of the small and large extracellular loops. Genmab used technology licensed from Medarex to generate

Interim Report for the First Half of 2021

the CD20 antibody forming part of ofatumumab. A SC formulation of ofatumumab was investigated in two Phase 3 ASCLEPIOS clinical studies (NCT02792218, NCT02792231) in RMS. The studies compared the efficacy and safety of SC ofatumumab versus teriflunomide in patients with RMS and were comprised of approximately 900 patients each. Based on these studies, Kesimpta (ofatumumab) was approved by the U.S. FDA in August 2020 and the European Commission (EC) in March 2021 for the treatment of RMS in adults. Kesimpta is the first B-cell therapy that can be self-administered by patients at home using the Sensoready autoinjector pen, once monthly after starting therapy. Additional studies with RMS patients are ongoing. Ofatumumab in RMS is being developed and marketed worldwide by Novartis under a license agreement between Genmab and Novartis Pharma AG. Under the terms of the agreement, Genmab is entitled to 10% royalties on net sales of Kesimpta.

Please consult the full U.S. Prescribing Information and the full European Summary of Product Characteristics for the labeled safety information for Kesimpta (ofatumumab).

First Quarter 2021 Updates

TEPEZZA (teprotumumab-trbw) First U.S. FDA-approved medicine for the treatment of thyroid eye disease