Genmab Announces Asset Exchange Agreement

Summary: Genmab signs asset exchange agreement.                                 

Copenhagen, Denmark; September 13, 2007 - Genmab A/S (OMX: GEN) announced today 
the execution of an asset exchange agreement with Medarex, Inc. Under the terms 
of the agreement, Genmab will receive full rights to HuMax-Inflam™/MDX-018,     
which targets IL-8, and Medarex will receive full rights to multiple disease    
programs in oncology. Genmab and Medarex will release to each other all         
previously held economic interests in the assets exchanged.                     
                                                                                
“Genmab will now hold all the rights to the HuMax-Inflam antibody which we have 
developed in cooperation with Medarex and hope to move the product into further 
clinical studies soon,” said Lisa N. Drakeman, Ph.D., Chief Executive Officer of
Genmab.                                                                         

About Genmab A/S                                                                
Genmab is a leading international biotechnology company focused on developing   
fully human antibody therapeutics for unmet medical needs.  Using unique,       
cutting-edge antibody technology, Genmab's world class discovery and development
teams have created and developed an extensive pipeline of products for potential
treatment of a variety of diseases including cancer and autoimmune disorders.   
As Genmab advances towards a commercial future, we remain committed to our      
primary goal of improving the lives of patients who are in urgent need of new   
treatment options.  For more information on Genmab's products and technology,   
visit www.genmab.com.                                                           

This press release contains forward looking statements. The words “believe”,    
“expect”, “anticipate”, “intend” and “plan” and similar expressions identify    
forward looking statements. Actual results or performance may differ materially 
from any future results or performance expressed or implied by such statements. 
The important factors that could cause our actual results or performance to     
differ materially include, among others, risks associated with product discovery
and development, uncertainties related to the outcome and conduct of clinical   
trials including unforeseen safety issues, uncertainties related to product     
manufacturing, the lack of market acceptance of our products, our inability to  
manage growth, the competitive environment in relation to our business area and 
markets, our inability to attract and retain suitably qualified personnel, the  
unenforceability or lack of protection of our patents and proprietary rights,   
our relationships with affiliated entities, changes and developments in         
technology which may render our products obsolete, and other factors. Genmab is 
not under an obligation to up-date statements regarding the future following the
publication of this release; nor to confirm such statements in relation to      
actual results, unless this is required by law.                                 

Genmab(R); the Y-shaped Genmab logo(R); HuMax(R); HuMax-CD4(R); HuMax-CD20(R);  
HuMax-EGFr(TM); HuMax-Inflam(TM); HuMax-TAC(TM); HuMax-HepC(TM); HuMax-CD38(TM);
HuMax-ZP3(TM); and UniBody(TM) are all trademarks of Genmab A/S.                

Contact: Helle Husted, Sr. Director, Investor Relations, T: +45 33 44 77 30, M: 
+45 25 27 47 13, E: hth@genmab.com                                              
                                                                                
Stock Exchange Release no. 39/2007                                              

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