Cancer Therapy Deal

Sareum Holdings PLC
22 September 2005


For immediate release                                          22 September 2005


                              SAREUM HOLDINGS PLC
                          ("Sareum" or the "Company")

                Collaboration with Infinity Pharmaceuticals Inc

Sareum Holdings plc (AIM: SAR), the specialist structure-based drug discovery
and services business, is pleased to announce that it has entered into a
collaborative agreement with Infinity Pharmaceuticals, Inc. (Infinity), a cancer
drug discovery company based in Cambridge, Mass. USA, to provide protein
structure determination capabilities to accelerate Infinity's drug discovery
research.  Sareum will utilise its skills in high throughput protein expression,
purification and structure determination to illustrate the precise nature of how
Infinity's potential drug candidates interact with target receptor proteins.
This detailed structural information will assist Infinity's scientists in their
search for new and improved cancer therapeutics by driving lead optimization
results and providing co-complex structures for Infinity's compounds.  Financial
terms of the agreement were not disclosed.

"We are delighted that Infinity has chosen Sareum as their partner in protein
structure determination," commented Dr. Tim Mitchell, Sareum's Chief Executive
Officer.  "This is our first protein structure determination collaboration in
the United States and a significant first step into a very important market. We
look forward to successful delivery of this project to Infinity and to closing
additional partnerships such as this."

Dr. Julian Adams, Infinity's Chief Scientific Officer remarked: "Sareum's
protein structure determination technologies and expertise will enhance
Infinity's ability to design better, more robust molecules for the creation of
new cancer treatments.  This partnership further illustrates Infinity's
commitment to accelerate the discovery of novel therapeutics for patients
suffering from cancer."



For further information please contact:

Sareum Holdings                                                     01223 497700
Tim Mitchell, Chief Executive Officer

Buchanan Communications                                            020 7466 5000
Tim Anderson, Mary-Jane Johnson

Infinity Pharmaceuticals, Inc.
Adelene Perkins, Chief Business Officer                             617.453.1000



About Sareum Holdings plc

Sareum Holdings plc is a specialist structure based drug discovery and services
business headquartered in Cambridge, UK. The Company was formed in August 2003
to discover new drugs for the treatment of cancer and to provide a range of drug
discovery services to the pharmaceutical industry. Sareum's unique approach aims
to halve the time it takes to discover new drug candidates.

Structure-based drug discovery involves the determination of a disease causing
protein's three-dimensional structure. Once the structure is known, novel
chemical entities are designed to 'lock-in' to the protein with the aim of
reversing or arresting a disease's progression.

Sareum's approach to structure based drug discovery is to produce multiple
recombinant proteins primarily through a baculovirus expression system;
determine their structure using x-ray crystallography; and then use its
innovative template-molecule x-ray screening technology to identify new chemical
entities designed to interact with the target protein. Sareum then uses its
high-throughput medicinal chemistry platform to rapidly synthesise further
molecules and develop the most promising into potential drug candidates.

Sareum provides its specialist drug discovery capabilities to partners in the
pharmaceutical and biotechnology industries. The Company aims to successfully
deliver: Programmes for complete gene-to-candidate structure-based discovery;
projects to accelerate or improve the productivity of specific activities; and
drug candidates for licensing at the Phase I or Phase II clinical trials stage.

Sareum joined the AIM Market of the London Stock Exchange in October 2004 and
trades under the symbol SAR. For further information, please visit
www.sareum.co.uk



About Infinity Pharmaceuticals, Inc.

Infinity is a fully integrated, cancer drug discovery company focused on
pathways of cancer cell survival. In addition, through select partnerships,
Infinity's distinctive, proprietary collection of small molecules is being used
against many of the world's most important diseases.  For more information,
please visit the Infinity website at http://www.ipi.com




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