AEA TECHNOLOGY QSA'S AURIGA MEDICAL TO MANUFACTURE BRACHYSIL

Global nanotechnology company pSivida Limited (ASX:PSD) is pleased to announce that its UK operating subsidiary pSiMedica Limited has signed an initial three year Manufacturing Agreement with AEA Technology QSA ("QSA") for the commercial manufacture of its lead brachytherapy product 32-P BioSiliconTM ("BrachySil") at QSA's Auriga Medical facility in Braunschweig, Germany.

Auriga Medical is the new brand name for products and services in nuclear medicine and radiation therapy within AEA Technology QSA, a subsidiary of AEA Technology plc (LSE:AAT.L). QSA is a world leader specializing in the supply of high quality and high performance radiation source products.

Under the terms of the agreement, Auriga Medical will manufacture BrachySil from BioSilicon using a process of neutron bombardment. BrachySil is comprised of particles of BioSilicon containing the radionuclide 32P (>99.9% purity). Auriga Medical will also manage the supply logistics for clinical and commercial use.

During the initial development phase of the Agreement, Auriga Medical will optimize the manufacturing process of BrachySil, and has begun the design and construction of a purpose built facility at its radiopharmacy in Braunschweig, Germany for both clinical trial and commercial supply. The facility will operate under cGMP manufacturing guidelines and be dedicated to the supply of BrachySil.

BrachySil has been developed by pSiMedica as a 'device' for the direct intratumoural treatment of cancers. Clinicians will receive BrachySil as a sterile powder for resuspension in an injectible aqueous formulation, administered via fine gauge needle using ultrasound or tomography for accurate placement.

pSivida Managing Director, Mr. Gavin Rezos said, "The signing of this important agreement with AEA Technology QSA GmbH marks a significant step forward in the commercialization of BioSiliconTM. AEA Technology QSA's Auriga Medical is a world leader in the manufacture of radiation source products and we are extremely pleased to have been able to secure their services for what is an integral role in the overall production and supply process. This relationship will service the pre-registration clinical trials as well as the market requirements for this unique product."

AEA Technology QSA Managing Director, Mr. Paul Brown said, "We welcome the opportunity to work with pSiMedica for the development and potential commercial realization of this exciting new brachytherapy modality. The innovative skills of our Auriga Medical development team and our new radiopharmaceutical manufacturing facility in Braunschweig are well suited to servicing pSiMedica's requirements."

Initial production of BrachySil at Auriga Medical's facilities will supply Phase IIa clinical trials at Singapore General Hospital, with primary liver cancer as the first clinical indication, scheduled to commence in May 2004. Phase IIb clinical trials are scheduled during Q1 2005 with product launch expected in 2006.

The Agreement with AEA Technology QSA can be extended by mutual agreement beyond the initial three year term.

pSiMedica is progressing discussions with potential development and marketing partners for BrachySilTM.

-ENDS-

Released by: Josh Mann Investor Relations pSivida Limited Tel: + 61 8 9226 5099 joshuamann@psivida.com.au

NOTES TO EDITORS

pSivida Limited

pSivida is an Australian-based biotechnology company committed to the biomedical applications of nano-technology and which has as its core focus the development and commercialisation of nano-structured porous silicon (BioSilicon) in biocompatible and biodegradable forms for use in healthcare through its UK subsidiary pSiMedica Limited, and in conjunction with QinetiQ plc (formerly the UK Government owned Defence Evaluation Research Agency, DERA). As a true 'platform technology', BioSilicon has multiple potential applications across the high growth healthcare sector, including controlled drug delivery, brachytherapy, tissue engineering and orthopaedics.

pSivida is listed on the Australian Stock Exchange (ASX Code: PSD). pSivida is also listed in Germany on the Frankfurt Stock Exchange on XETRA system, as well as Berlin, Munich and Stuttgart, ( German Symbol: PSI. Securities Code (WKN) 358705).

For more information visit www.psivida.com.au

pSiMedica Limited (UK)

pSiMedica has identified a biocompatible and biodegradable form of silicon (BioSilicon). The technology is based on applying a modified form of the silicon chip (porosified or nano-structured silicon) in a variety of healthcare applications, ranging from controlled drug delivery, brachytherapy, tissue engineering and orthopaedics to clinical diagnostics.

pSiMedica's market strength lies in its international management and science team, including former Chairman of SmithKline & French Research, Dr Roger Brimblecombe, former PepTech CEO Dr Roger Aston, and, the world eminent scientist and the inventor of BioSilicon, Professor Leigh Canham. The Company has access to cutting edge research and development facilities of QinetiQ plc, the largest research and development institution in Europe.

pSiMedica owns the worldwide intellectual property rights to nano-structured porous silicon, known as BioSilicon, for use in or on humans and is dedicated to realising the potential of porous silicon products in areas such as controlled drug delivery, diagnostics and orthopaedics.

For more information visit www.psimedica.co.uk

Auriga Medical

Auriga Medical is the new brand name for products and services in nuclear medicine and radiation therapy within AEA Technology QSA, a subsidiary of AEA Technology plc (AAT.L on the London Stock Exchange).

Focussing on the therapeutic use of radioisotopes, especially the exciting areas of brachytherapy and radioimmunotherapy, Auriga Medical draws on over 50 years of QSA's experience in the processing of radioisotopes and the design and manufacture of sealed radiation sources.

Website address: www.aurigamedical.com

AEA Technology QSA

The QSA business is an international market leader in the production of high-quality radioactive products for medical, industrial, environmental and research applications. Having been divested from Nycomed Amersham plc in February 1998, QSA has since consolidated its manufacturing sites to the USA, Germany and China. Employing 310 staff worldwide QSA utilises its core skills in the production, handling, encapsulation and distribution of radioactive materials to satisfy worldwide customer demands. In the 2002-2003 financial year QSA achieved a turnover of £35.9m and an operating profit of £2.6m

Website address: www.qsa.aeat.com

AEA Technology plc

One of the world's leading innovation businesses, AEA Technology turns science and engineering into profit for the benefit of its customers and investors. AEA Technology has years of experience in understanding complex industrial processes and managing the way in which they interact with each other and their environment. The innovative delivery of knowledge and skills differentiates AEA Technology from its competitors.

The business focuses on five key areas: technology-based products, specialised science, environmental management, improving the efficiency of industrial plant, and risk assessment and safety management. In each area AEA Technology offers services, products, consultancy, software and technology transfer.

Operating in 31 countries in Europe, North America, the Middle East and Asia Pacific, AEA Technology's main markets are rail, utilities and infrastructure, processing and manufacture, oil and gas, pharmaceuticals, and defence, together with government and public sector organisations.

Benefiting from a highly-qualified workforce - over half are graduate scientists or engineers, and ten per cent have PhD's - AEA Technology seeks to be recognised as the world's most successful innovation business.

In the 2002-2003 financial year turnover was £272.3 million and (loss)/profit before tax was (£5.4) million.

AEA Technology plc is listed on the London Stock Exchange (LSE: AAT.L) in the Support Services sector.

Website address: http://www.aeat.co.uk