Phase IIb Study Involving Approximately 300 Patients Initiated

Copenhagen, Denmark; September 19, 2002 - Genmab A/S (CSE: GEN and FSE: GE9D) announced today that the US Food and Drug Administration (FDA) had approved the Investigational New Drug (IND) filing for HuMax-CD4 for psoriasis and the initiation of a Phase IIb study. This will be the fifth study carried out by Genmab with HuMax-CD4 for psoriasis or rheumatoid arthritis (RA) indications.

About the Study
This study will involve around 300 patients with moderate to severe psoriasis vulgaris at 40 trial sites in the US, Canada and Europe that include both hospitals and specialist dermatology clinics. The objectives of the Phase IIb study are to confirm the efficacy and safety of HuMax-CD4 in the treatment of psoriasis in comparison to placebo. Patients will be treated with one of three doses of HuMax-CD4 or placebo for 13 weeks. Efficacy of HuMax-CD4 will be assessed by means of the recognized PASI score.

“This filing shows that Genmab is on track to achieving its goals for IND filings this year,” said Lisa Drakeman, Ph.D., Chief Executive Officer of Genmab. “Genmab employees are committed to maintaining the pace of our clinical development programs in order to bring urgently needed therapeutics to patients who need them.”

Background
HuMax-CD4 and Previous Clinical Experience

HuMax-CD4 is a high affinity human antibody that targets the CD4 receptor on T-lymphocytes. These cells are involved in promoting autoimmune disease and an antibody that targets them can be used for the treatment of several inflammatory diseases including RA and psoriasis.

Psoriasis
The results of a small, placebo controlled Phase II study designed to establish the safety and lowest effective dose of HuMax-CD4 in patients with moderate to severe psoriasis were presented earlier this year. Eighty-five patients received placebo or one of four dose levels (20, 80, 160, 280 mg) of HuMax-CD4 once weekly for four weeks. After the last treatment, the patients were followed over a period of 11 weeks with the primary assessment of efficacy at week 7. Four weeks of HuMax-CD4 treatment was safe and well tolerated. PASI was reduced with increased dose levels. Mean PASI was reduced by 12 percent, 14 percent, 16 percent and 24 percent in the active dose groups, respectively. At the highest dose level, 38 percent of the patients obtained more than 25 percent reduction of PASI and half of those patients obtained more than 50 percent reduction of their PASI. The efficacy results obtained after just four weeks of treatment indicate that longer treatment would lead to even further reduction of PASI. Additional data has shown that a number of patients experienced long-lasting effects from the treatment. Out of 68 patients treated with HuMax-CD4, 19 achieved at least a 25 percent reduction of the PASI score at the trial endpoint at week seven (four weeks after the last treatment). Over half still maintained that score 12 weeks after the last treatment. This means ten (53 percent) of the 19 patients saw long-lasting results during the three months after the last injection. Five patients even maintained a 50 percent reduction of PASI 12 weeks after.

Rheumatoid Arthritis
Genmab presented Phase I/II clinical trial results in patients with RA in November 2000 at the American College of Rheumatology (ACR) meeting. In this study, severely diseased patients who had failed to respond to conventional therapy received a single dose of the antibody. HuMax-CD4 was safe and well tolerated. Furthermore, in the four highest dose cohorts, 50 percent of the treated patients achieved favorable responses to the antibody as measured by objective criteria defined by the ACR, achieving responses ranging from ACR20 to ACR70.

HuMax-CD4 is the subject of two on-going studies in RA: A Phase II study in a broad RA indication for patients with active arthritis despite treatment with methotrexate and a Phase III study to treat patients with active RA who have failed to respond to treatment with Methotrexate and TNF-a blocking agents. Based on this study, HuMax-CD4 was designated a Fast Track Product by the FDA.