Copenhagen, Denmark; December 19, 2003 – Genmab A/S (CSE: GEN) announced that it is filing an IND today in the US and a CTA in England to start an open label Phase I/II clinical trial using HuMax-CD20 in patients with relapsed or refractory follicular lymphoma. Follicular lymphoma is the second most common lymphoma in US and Europe, accounting for 11% to 35% of all non-Hodgkin’s lymphoma.

The trial is expected to include 40 patients, and will be a dose escalation study. Patients will receive 4 weekly doses of either 300, 500, 700 or 1000mg of HuMax-CD20 with a total of 10 patients treated at each dose level. The primary objective will be to assess the safety and the efficacy of HuMax-CD20.

“HuMax-CD20 has performed well in a variety of pre-clinical tests,” said Lisa N. Drakeman, Ph.D., Chief Executive Officer of Genmab. “We are very happy with the progress made to date and are eager to advance HuMax-CD20 to Phase I/II clinical trials.”

About HuMax-CD20

HuMax-CD20 is a human antibody which is effective at binding to the disease target, and releases only very slowly from the target over time. In February 2003, Genmab presented data from pre-clinical laboratory tests showing HuMax-CD20 appeared to kill tumor cells that were resistant to rituximab, a marketed cancer therapy. The data showed the antibody highly effective in inducing complement mediated cytotoxicity (cell destruction) of B-cell tumors. Subsequently, Genmab has collected data that appears to show HuMax-CD20 is also effective in inducing Natural Killer cell-mediated cytotoxicity of B-cell tumors. Further, in a 92 day primate study, HuMax-CD20 effectively depleted B-cells from blood and lymph nodes.  In this study, HuMax-CD20 appeared to deplete B-cells for a period of time that was four times longer than rituximab. 

In another study it was found that HuMax-CD20 binds to a unique site on CD20 target cells when compared to other known CD20 antibodies. This is a distinguishing characteristic of HuMax-CD20 and may help explain why HuMax-CD20 has outperformed other CD20 antibodies in a variety of pre-clinical studies. Furthermore, in a novel cancer disease model in immuno-compromised mice using sensitive bio-luminescence imaging, new data show that HuMax-CD20 appears to stop growth of B-cell tumors grown from a laboratory cell line far more effectively than either placebo, or a marketed treatment, rituximab.

About CD20

The CD20 antigen is a transmembrane protein on pre-B and mature B lymphocytes. CD20 appears to act as a calcium ion channel, and to regulate early steps in B lymphocyte activation. The molecule is not shed from the cell surface, and is not internalized upon antibody binding. CD20 is found on over 90% of B-cell lymphomas, as well as other lymphoid tumors of B-cell origin.