Copenhagen, Denmark; December 12, 2005 – Genmab A/S (CSE: GEN) announced today that HuMax®-CD20 induces rapid responses in patients with relapsed chronic lymphocytic leukemia (CLL) in the ongoing phase I/II study.  Responses generally appeared early with 67% evaluable patients treated at the highest dose level (2,000 mg) responding to treatment at week 4. Twelve of 26 patients (46%) obtained objective responses lasting at least 8 weeks by the NCI working group guidelines for CLL including 2 nodular partial remissions.

 

The 67% responding patients observed at week 4 included 16 patients showing responses by physical examination and peripheral blood evaluation. Ten patients showed complete responses by absence of enlarged lymph nodes, spleen and liver, and by normalization of blood counts at any time point during the 19 week follow up period.

 

By the NCI working group guidelines for CLL, complete response must be confirmed with CT scan and bone marrow samples. Under the protocol, these were not scheduled to occur until week 19 at the minimum and could take place up to week 26, which could be over 5 months since the response was initially observed.

 

HuMax-CD20 also induced marked effects in the bone marrow of several patients in the study.

 

The median time to progression in the 12 responding patients has not yet been reached, but will exceed 19 weeks.  The time to response is very short with 16 of 26 patients obtaining a clinical complete or partial response at week 4.

 

The pharmacokinetics in the study support the use of HuMax-CD20 in CLL and indicate that responses and their duration may further improve with continued treatment.

HuMax-CD20 was well tolerated by CLL patients in the study and the maximum tolerated dose was not reached.

 

Professor Herve Tilly of Centre Henri Becquerel in Rouen, France, presented the data today during an oral presentation at the 2005 Annual Meeting of the American Society of Hematology.  Selected slides from the presentation will be available at www.genmab.com.

 

“According to the results of this ongoing study, HuMax-CD20 shows promise in the treatment of relapsed CLL patients on several fronts,” said Lisa N. Drakeman, Ph.D., Chief Executive Officer of Genmab. “We are very pleased with the way patients are responding to treatment and look forward to moving this product into pivotal studies.”

 

Conference Call

Genmab will hold a conference call about the news today, Monday, December 12, 2005 at

 

8:45 p.m. CET

7:45 p.m. GMT

2:45 p.m. EST

 

The dial in numbers are as follows:

 

+1 800-289-0743 (in the US) and ask for the Genmab conference call

+1 913-981-5546 (outside the US) and ask for the Genmab conference call

 

The conference call will be held in English.

 

About the study

The study is an open-label dose escalation trial that enrolled 33 patients with CLL who had failed previous therapy. The trial has three dose levels. Three patients at the first dose level received an initial dose of 100 mg followed by three weekly doses of 500 mg, at the second dose level three patients received a dose of 300 mg followed by three weekly doses of 1,000 mg and at the third level, 27 patients received an initial dose of 500 mg followed by three weekly doses of 2,000 mg.

 

The total follow up period for this study is 12 months from treatment start and the primary endpoint of the trial is objective response over the period from screening to week 19.

 

NCI working group guidelines

Responses criteria were those defined by the National Cancer Institute Working Group.  Under these criteria responses are assessed by physical evaluation, peripheral blood counts, and by CT scan, and bone marrow biopsy for responders. Response (complete or partial) must be maintained for a period of at least 2 months.

 

The National Cancer Institute – sponsored Working Group (NCI-WG) on CLL published guidelines for the design and conduct of clinical trials in CLL with the objective to facilitate comparisons of results of clinical trials in CLL by providing standardized eligibility, response and toxicity criteria. According to the guidelines, a complete remission (CR) is obtained when there is an absence of lymphadenopathy by physical examination and appropriate radiographic technique, spleen and liver are normal in size, absence of constitutional symptoms, and normal peripheral blood counts. A bone marrow aspirate and biopsy should be performed 2 months after clinical and laboratory results have demonstrated that all above mentioned criteria has been fulfilled. The examination must show: normocellular for age, lymphocytes < 30% and no nodules.  A nodular partial remission has the same definition as for CR but with persistent nodules in the bone marrow. A partial remission requires a more than 50% decrease in peripheral blood lymphocyte count, a more than 50% reduction in lymphadenopathy, a more than 50% reduction in size of liver and spleen if abnormal at baseline and a more than 50% improvement in peripheral blood cell counts if not normal. Response must be maintained for a period of at least 2 months.

 

Fast Track Status

HuMax-CD20 received a Fast Track designation from the US Food and Drug Administration in December 2004 for Genmab’s CLL development program.

 

About CLL

CLL is the most common leukemia in adults in the US and most of Western Europe. The incidence is 8,100 to 12,500 new cases in the US per year and 85-95% of the cases are of B-cell origin. CLL is a subgroup of non-Hodgkin’s lymphoma (NHL) and together with small lymphocytic lymphoma (SLL) corresponds to around 20% of all NHL cases.