CAT Reports HGS Progress

Cambridge Antibody Tech Group PLC
19 March 2003



03/CAT/09

Page 1 of 2

FOR IMMEDIATE RELEASE

11.15 GMT 06.15 EST 19 March 2003


For further information contact:

Cambridge Antibody Technology
Tel: [phone]                              Weber Shandwick Square Mile (Europe)
Peter Chambre, Chief Executive Officer                 Tel: [phone]
John Aston, Chief Financial Officer                    Graham Herring
Rowena Gardner, Director of Corporate Communications


Human Genome Sciences, Inc                             BMC Communications/The Trout Group (USA)
Tel: [phone]                                  Tel: [phone]
Jerry Parrott, Corporate Communication                 Brad Miles, ext 17 (media)
                                                       Brandon Lewis, ext.15 (investors)


CAMBRIDGE ANTIBODY TECHNOLOGY REPORTS

THE DEVELOPMENT OF ABTHRAXTM
BY HUMAN GENOME SCIENCES, INC



Cambridge, UK... Cambridge Antibody Technology (LSE: CAT; NASDAQ: CATG) today
acknowledges the announcement by Human Genome Sciences, Inc. (NASDAQ: HGSI) that
it has discovered and developed a human monoclonal antibody drug, ABthraxTM,
that is effective in protecting against anthrax in multiple experimental models.
HGSI plans to file an Investigational New Drug application in the near future,
seeking clearance from the Food and Drug Administration (FDA) to begin clinical
trials in the US to evaluate the safety, tolerability and pharmacology of
ABthrax in healthy adults.


CAT confirms that the ABthrax antibody was isolated and developed by HGSI from
libraries it has licensed to HGSI.


Peter Chambre, CAT's Chief Executive Officer, comments 'We are delighted with
the success that HGSI is having in working with the libraries we licensed to
them. ABthrax is the fourth human monoclonal antibody to come from CAT's
collaboration with HGSI and we continue to be pleased with the productivity of
this relationship'.


CAT has already received a licence fee for the antibody and is entitled to
receive clinical development milestones and royalties on product sales from
HGSI.


The full text of the HGSI announcement is available on the HGSI website,
www.hgsi.com


- ENDS -


Notes to Editors

Cambridge Antibody Technology (CAT):

•        CAT is a UK-based biotechnology company using its proprietary
technologies and capabilities in human monoclonal antibodies for drug discovery
and drug development. Based near Cambridge, England, CAT currently employs
around 290 people.

•        CAT is a leader in the discovery and development of human therapeutic
antibodies and has an advanced proprietary platform technology for rapidly
isolating human monoclonal antibodies using phage display systems. CAT has
extensive phage antibody libraries, currently incorporating more than 100
billion distinct antibodies. These libraries form the basis for the Company's
strategy to develop a portfolio of antibody-based drugs.

•        HumiraTM is the leading CAT-derived antibody. Six other CAT-derived
human therapeutic antibodies are at various stages of clinical trials.

•        CAT has alliances with a large number of pharmaceutical and
biotechnology companies to discover, develop and commercialise human monoclonal
antibody-based products. CAT has also licensed its proprietary human phage
antibody libraries to several companies for target validation and drug
discovery. CAT's collaborators include: Abbott, Amgen, Amrad, Chugai, Elan,
Genzyme, Human Genome Sciences, Merck & Co, Pharmacia and Wyeth Research.

•        CAT is listed on the London Stock Exchange and on NASDAQ since June
2001. CAT raised £41m in its IPO in March 1997 and £93m in a secondary offering
in March 2000.

Application of the Safe Harbor of the Private Securities Litigation Reform Act
of 1995:

This press release contains statements about Cambridge Antibody Technology Group
plc ('CAT') that are forward looking statements. All statements other than
statements of historical facts included in this press release may be forward
looking statements within the meaning of Section 21E of the Securities Exchange
Act of 1934. These forward looking statements are based on numerous assumptions
regarding CAT's present and future business strategies and the environment in
which CAT will operate in the future. Certain factors that could cause CAT's
actual results, performance or achievements to differ materially from those in
the forward looking statements include: market conditions, CAT's ability to
enter into and maintain collaborative arrangements, success of product
candidates in clinical trials, regulatory developments and competition.


                      This information is provided by RNS
            The company news service from the London Stock Exchange