Genmab Announces Financial Results for the First Quarter of 2021

Genmab Announces Financial Results for the First Quarter of 2021

May 5, 2021; Copenhagen, Denmark;

Genmab Interim Report for the First Quarter Ended March 31, 2021

"In 2020, Genmab reached an inflection point in our evolution into a fully integrated biotech innovation powerhouse. This momentum has continued into the first quarter of 2021, with the BLA submission for tisotumab vedotin, our product in development with Seagen. If approved by the U.S. FDA, we believe that tisotumab vedotin as monotherapy has the potential to become an important treatment option for women with recurrent or metastatic cervical cancer, who have disease progression on or after chemotherapy," said Jan van de Winkel, Ph.D., Chief Executive Officer of Genmab.

Financial Performance First Quarter of 2021

Genmab is maintaining its 2021 financial guidance published on February 23, 2021.

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

Genmab Announces Financial Results for the First Quarter of 2021

+1 631 913 1422 (U.S. participants) or +44 3333 000804 (international participants) and provide conference code 29164332.

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 Quarter of 2021

Interim Report for the First Quarter of 2021

CONSOLIDATED KEY FIGURES

* Cash, cash equivalents, and marketable securities.

** Full-time equivalent

Interim Report for the First Quarter of 2021

Genmab is maintaining its 2021 financial guidance published on February 23, 2021.

We expect our 2021 revenue to be in the range of DKK 6,800-7,500 million, compared to DKK 10,111 million in 2020. Our revenue in 2020 was significantly impacted by the AbbVie Inc. (AbbVie) collaboration and included DKK 4,398 million related to the portion of the upfront payment that was allocated to the license grants and recognized as revenue in 2020.

Our projected revenue for 2021 primarily consists of DARZALEX royalties of DKK 4,900-5,300 million. Such royalties are based on estimated DARZALEX 2021 net sales of USD 5.2-5.6 billion compared to actual net sales in 2020 of USD 4.2 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 sales. Given the ongoing arbitration, Genmab has reflected this as a reduction to estimated 2021 revenue. The remainder of our revenue consists of royalties from TEPEZZA and Kesimpta, reimbursement revenue, milestones for epcoritamab and daratumumab, and other milestones.

We anticipate our 2021 operating expenses to be in the range of DKK 5,500-5,800 million, compared to DKK 3,798 million in 2020. The increase is driven by the advancement of our clinical programs, continued investment in research and development, as well as building our commercial organization and infrastructure.

We expect our operating result to be in the range of DKK 1,000-2,000 million in 2021, compared to DKK 6,313 million in 2020.

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 our collaboration agreements; our ongoing binding arbitration of two matters under our license agreement with Janssen relating to daratumumab; the timing and variation of development activities (including activities carried out by our collaboration partners) and related income and costs; DARZALEX, Kesimpta and TEPEZZA net sales and royalties paid to Genmab; and currency exchange rates (the 2021 guidance assumes a USD/DKK exchange rate of 6.0). In December 2020, Horizon Therapeutics announced that there was a supply disruption related to the production of TEPEZZA due to U.S. government-mandated COVID-19 vaccine production requirements. Subsequently, in March 2021, Horizon Therapeutics announced its plans to resupply the market beginning in April 2021. 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 our business and financial performance, including our clinical trials, projected regulatory approval timelines, supply chain and

Interim Report for the First Quarter of 2021

revenues, and cause our actual results to differ materially from our 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 our product candidates and on net sales of approved products created by Genmab and developed and marketed by our collaboration partners. The longer the pandemic continues, the more severe the impacts described below will be on our 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 our workplace and on our communities, and ensures business continuity. Genmab is also actively monitoring the potential impact on our 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 our 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 our business and financial performance, including on the net sales of DARZALEX, Kesimpta and TEPEZZA, by our partners and on our royalty and milestone revenue therefrom.

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

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

PRODUCT PIPELINE AND TECHNOLOGY PROGRESS FIRST QUARTER OF 2021

As of the end of the first quarter, Genmab's proprietary pipeline of product candidates, where we are responsible for at least 50% of development, consisted of eight clinical stage antibodies. In addition to our own pipeline, there are also 15 products in development by third-party companies, including three approved products, which incorporate Genmab technology and innovation. Beyond the antibodies in clinical development, our pipeline also includes around twenty in-house and partnered pre-clinical programs. An overview of the development status of each of our products is provided in the following

Interim Report for the First Quarter of 2021

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.

Approved Medicines Created by Genmab1

1Products developed and marketed by others incorporating Genmab technology and innovation

2See 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

Interim Report for the First Quarter of 2021

through 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. Daratumumab (marketed as DARZALEX for intravenous administration and as DARZALEX FASPRO in the United States and as DARZALEX SC in Europe for subcutaneous administration) is approved in certain territories for the treatment of adult patients with certain multiple myeloma indications. DARZALEX FASPRO is also approved in the United States 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 the labeled safety information.

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 the CD20 antibody forming part of ofatumumab. A SubQ formulation of ofatumumab was investigated in two Phase 3 ASCLEPIOS clinical studies in RMS. The studies compared the efficacy and safety of SubQ 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 all the labeled safety information for Kesimpta.

First Quarter 2021 Updates

Interim Report for the First Quarter of 2021

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

Teprotumumab, approved by the U.S. FDA in January 2020 under the trade name TEPEZZA, is a human monoclonal antibody that targets the Insulin-like Growth Factor 1 Receptor (IGF-1R), a well-validated target. Genmab used technology licensed from Medarex to generate the IGF-1R antibody forming part of teprotumumab. TEPEZZA is being developed and is commercialized by Horizon. The antibody was created by Genmab under a collaboration with Roche and development and commercialization of the product is now being conducted by Horizon under a license from Roche. Under the terms of Genmab's agreement with Roche, Genmab will receive mid-single digit royalties on sales of TEPEZZA. In December 2020, Horizon Therapeutics announced that there was a supply disruption related to the production of TEPEZZA due to U.S. government-mandated COVID-19 vaccine production requirements. Subsequently, in March 2021, Horizon Therapeutics announced its plans to resupply the market beginning in April 2021.

Please consult the full U.S. Prescribing Information for all the labeled safety information for TEPEZZA.

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

Interim Report for the First Quarter of 2021

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.

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 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) and in combination with standard of care therapies for B-NHL are ongoing.

First Quarter 2021 Updates

Interim Report for the First Quarter of 2021

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. A Phase 1/2 clinical study of DuoBody-PD-L1x4-1BB in solid tumors is 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.

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 trial in solid tumors is ongoing.

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

Interim Report for the First Quarter of 2021

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 trial 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 trial in malignant 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 (CTA submissions) in Europe in November 2020. The first patient was dosed in the first-in-human study in March 2021.

First Quarter 2021 Update

Interim Report for the First Quarter of 2021

Product Candidates Incorporating Genmab's Innovation

In addition to Genmab's own pipeline of product candidates, our innovations are found 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.

Pre-clinical Programs