Proposed Acquisition

Proteome Sciences PLC
31 May 2002

                             Proteome Sciences plc

                                 PRESS RELEASE


 PROTEOME SCIENCES ANNOUNCES PROPOSED ACQUISITION OF AVENTIS R AND T PROTEOMICS
                                    DIVISION


For Immediate Release  31st May, 2002

The Board of Proteome Sciences plc (Proteome Sciences) is pleased to announce
that non-binding Heads of Agreement have been signed for the Company to acquire
Xzillion Proteomics GmbH & Co. KG (Xzillion) the proteomics division of Aventis
Research and Technologies GmbH & Co. KG (Aventis R&T).


Negotiations finalising the formal documentation are in progress, subject to an
exclusivity agreement between the parties and it is anticipated that completion
of the transaction will take place by the end of June. The considerationfor the
acquisition which values Xzillion at £12.6m, will be satisfied by the issue of
18 million new ordinary shares of 1p each in the Company,at based on a price of
70p per share. Following the issue of these shares, and the placing announced
today, Aventis R&T will own (??14.8% ??) 15.8% of the enlarged share capital of
Proteome Sciences.


It is anticipated that formal completion of the transaction will take place by
the end of June fFollowing completion whichDr. Wolfgang SchuelleSchuller, Chief
Executive Officer of Aventis R&T, will be invited to join the Board as a non
executive director. At the time of completion, it is expected that Xzillion will
have cash holdings of £3.5m. Xzillion has entered into a strategic research
agreement with Aventis Pharma in proteomics.


Xzillion owns a proprietary technology PST (Protein Sequence Tags) which offers
an exponential improvement in speed, sensitivity protein coverage, accuracy and
cost efficiency in the field of high throughput protein expression.


These integrated and automated technologies provide a unique way to discover
novel proteins as targets or markers or to identify the mode of action of drugs
and drugs targets. These are entirely complementary to Proteome Sciences
activities.


Christopher Pearce, Chief Executive of Proteome Sciences, said :


'The proposed acquisition of Xzillion provides Proteome Sciences with high
throughput capacity to add to our existing high sensitivity protein separation
and characterisation techniques. This takes us closer to drug discovery, drug
candidate selection and lead optimisation and consolidates Proteome Sciences'
position as a leader in proteomics in human diseases. The transaction should
accelerate the development and commercialisation of novel diagnostic, prognostic
and therapeutic applications'.


Dr. Wolfgang Schuller, CEO of Aventis R&T commented :


'The combination of Xzillion's technology position with Proteome Sciences's
position in patented protein targetsdifferential protein expressions in disease
offers tremendous opportunities to the combined business in the market, that
each stand alone company would never achieve in a comparable time.'


For further information please contact:



Proteome Sciences plc                Tel : [phone]

Christopher Pearce, Chief Executive  e-mail : [e-mail]

www.proteome.co.uk



Public Relations for Proteome Sciences

Ikon Associates

Adrian Shaw Tel : [phone]

Mobile : + 44(0) 797 9900733

e-mail : [e-mail]



Aventis Research &Technologies GmbH & Co KG

Dr. Wolfgang Schuller

Chief Executive

Industrial Park Hoechst

Building G865

65926 Frankfurt/M

Germany



Ulrich Auch  Tel : [phone]



Notes to Editors

Proteome Sciences plc applies high sensitivity proteomics to identify and
characterise differential protein expression in diseases for diagnostic,
prognostic and therapeutic applications. It has to date developed sensitive
blood assays for stroke, nvCJD, BSE and solid organ transplantation.


The main focus of its research currently addresses neurological,
neurodegenerative, diabetes/obesity, oncology and cardiovascular conditions.
Commercialisation of these programmes will be effected through strategic
partnerships.


Proteome Sciences is also the largest shareholder in Intronn Inc., the US
Company that has developed SMaRTTM, a technology able to modify gene expression
at the mRNA level.




                      This information is provided by RNS
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