Collaborative Agreement

CAMBRIDGE ANTIBODY TECHNOLOGY GROUP PLC
9 August 1999

CAMBRIDGE ANTIBODY TECHNOLOGY AND HUMAN GENOME SCIENCES FORM ALLIANCE IN
THERAPEUTIC ANTIBODIES

Major new initiative for the development of human therapeutic antibody
products against genomics targets

Melbourn, UK and Rockville, MD, USA Cambridge Antibody Technology Group plc
('CAT') (LSE: CAT) today announces a collaborative agreement with Human Genome
Sciences, Inc. ('HGS') (NASDAQ: HGSI) for the development of fully human
monoclonal antibody therapeutics. The alliance will harness CAT's expertise in
the generation and optimisation of fully human monoclonal antibodies for up to
three target human proteins identified by and proprietary to HGS.  

CAT will use its high throughput antibody isolation technologies to rapidly
generate high affinity, fully human monoclonal antibodies specific for HGS
proteins, to explore their role in a multitude of disease indications for the
development of novel therapeutics. The initial focus will be on a fast-track
proprietary antigen that HGS has discovered through its genomics programs.

William A. Haseltine, PhD., Chairman and Chief Executive Officer of Human
Genome Sciences said, 'We are delighted to initiate a collaboration with
Cambridge Antibody Technology.  Combining the technologies of our two
companies is a natural.  We are experts in the identification of hundreds of
novel human proteins that are found on the surface of cells, tissues and
organs;  they are experts in identifying large numbers of human antibodies
that recognize such proteins that may be useful as drugs and other
pharmaceutical products.  This is our second Transatlantic alliance with a
biotechnology company, reflecting the increasing strength of this sector of
the European economy.  HGS is a pioneer in seeking out such collaborations'.

Commenting on the alliance, Dr David Chiswell, CAT's Chief Executive Officer
said,
'The potential to develop novel therapeutic products by combining Human Genome
Sciences' unique genomics expertise with CAT's capacity for rapid generation
of fully human antibodies is extremely exciting. In fact, an early
demonstration of the power of combining two such powerful technologies is
evident in that CAT has already identified more than 400 different human
antibodies that bind to HGS' first target, many of which are high affinity
and/or biologically active. Such a large number of potential product
candidates could not be generated by any other approach.' 
CAT would receive milestone and royalty payments on products and will receive
research support funding. CAT and its partners have already initiated clinical
trials on three human antibodies, targeting TNFa for rheumatoid arthritis,
IL-12 for autoimmune disease and TGFb2 for ocular fibrosis.  


For Further Information Contact:

Human Genome Sciences
Kate de Santis, Director, Investor Relations
                                      Tel: [phone]

Cambridge Antibody Technology Group plc
Dr David Chiswell, Chief Executive Officer
Dr Debbie Allen, Business Development Manager              
Diane Mellett, VP Legal Affairs       Tel: [phone]       

HCC De Facto (press enquiries)
City/Financial, Rebecca Hennessy       
Trade/Science, Nikul Odedra           Tel: [phone]