Copenhagen, Denmark; December 1, 2004 – Genmab A/S (CSE: GEN) announced today encouraging efficacy data from a Phase I/II trial using HuMax™-EGFr to treat patients with head and neck cancer. Two types of scanning were used to evaluate the 17 patients who completed both the single and multiple dosing parts of the trial. Using a type of scan known as FDG-PET, which visualizes the tumor metabolism, a total of 15 out of 17 patients were able to be evaluated. Six out of the 15 showed a partial metabolic response (PMR) and 3 patients out of the 15 showed a stable metabolic disease (SMD). All these patients were in the 2, 4, or 8 mg/kg dose group. All patients in the 4 and 8 mg/kg dose group obtained a PMR or SMD.

Using the computerized tomography (CT scan) method, 16 patients out of the total 17 could be evaluated. Out of the 16, 2 patients showed a partial response (PR) and 8 patients showed stable disease (SD), with all these responses occurring in the 1, 2, 4 and 8 mg/kg dose groups.  Six out of 7 patients in the 4 and 8 mg/kg group obtained a PR or SD.

The frequency of acneiform rashes increased with dose so that 7 out of 8 patients receiving 4 or 8 mg/kg experienced rash.

A total of 24 patients were treated with a single dose of HuMax-EGFr and in October 2004 Genmab released data showing a favorable safety profile for the antibody in doses up to 8mg/kg. Six patients did not proceed to the multiple dosing part of the study due to disease progression and one patient only received one infusion in the multi dosing part of the trial. As no patients experienced dose limiting toxicities and a maximum tolerated dose was not reached and additional patients are being added to the 8mg/kg level. Genmab expects to present complete data from the study, including information from the additional patients at a scientific conference during 2005.

“We are pleased to see encouraging efficacy data from both the FDG-PET scanning and the CT scanning methods,” said Lisa N. Drakeman, Ph.D., Chief Executive Officer of Genmab. “We look forward to seeing more data next year.”

About the Trial

Patients suffering from head and neck cancer who had failed standard therapies were treated initially with a single-dose of 0.15, 0.5, 1, 2, 4 or 8 mg/kg of HuMax-EGFr. Following a safety evaluation at day 28, patients then received the four additional doses at the same dose level, at weekly intervals. Four patients were included at each dose level. The primary objective of the study was safety, and efficacy was evaluated by FDG-PET and CT one week after the final dose.