Exhibit 99.1 Genmab Announces Financial Results for the First Quarter of 2023 May 10, 2023 Copenhagen, Denmark; Interim Report for the First Quarter Ended March 31, 2023 Highlights ● Genmab revenue increased 35% compared to the first quarter of 2022, to DKK 2,854 million “In the first quarter of the year we continued to lay the groundwork for the potential approval of epcoritamab in relapsed/refractory diffuse large B-cell lymphoma (DLBCL). Looking beyond this indication, together with our partner AbbVie In ...