ROCKVILLE, MD - (August 12, 2003) - Shire Pharmaceuticals Group plc announces issuance of patent #6,605,300 for a multiple pulsed dose drug delivery system.

   Oral Pulsed Dose Drug Delivery System

   Abstract

   A multiple pulsed dose drug delivery system for pharmaceutically active amphetamine salts, comprising an immediate-release component and an enteric delayed-release component wherein (1) the enteric release coating has a defined minimum thickness and/or (2) there is a protective layer between the pharmaceutically active amphetamine salt and the enteric release coating and/or (3) there is a protective layer over the enteric release coating. The product can be composed of either one or a number of beads in a dosage form, including either capsule, tablet, or sachet method for administering the beads.

   About Shire Pharmaceuticals Group plc

   Shire is a fast-growing international specialty pharmaceutical company with a strategic focus on four therapeutic areas: central nervous system disorders, oncology/hematology, antivirals, and biologics. The Group has a global sales and marketing infrastructure with a broad portfolio of products and its own direct marketing capability in the US, Canada, UK, Republic of Ireland, France, Germany, Italy, and Spain, with plans to add Japan by 2004. Shire also covers other significant pharmaceutical markets indirectly through distributors.

   THE "SAFE HARBOR" STATEMENT UNDER THE PRIVATE SECURITIES LITIGATION REFORM ACT OF 1995. The statements in this press release that are not historical facts are forward-looking statements that involve risks and uncertainties, including but not limited to, risks associated with the inherent uncertainty of pharmaceutical research, product development and commercialisation, the impact of competitive products, patents, and other risks and uncertainties, including those detailed from time to time in periodic reports, including the F-4 Prospectus and the Annual Report filed on Form 10K by Shire with the Securities and Exchange Commission.

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