Shire Pharmaceuticals Group plc
Hampshire International Business Park,
Chineham, Basingstoke RG24 8EP  UK
Tel +44 1256 894000 Fax +44 1256 894708
http://www.shire.com

12 noon (BST) 7am (EDT)                                     Shire



          Shire to conduct new ADDERALL XR(R) programme in adolescents
             Programme would add six months Hatch-Waxman exclusivity


Basingstoke, UK - 8 May 2003 - Shire Pharmaceuticals Group plc (LSE: SHP,
NASDAQ: SHPGY, TSX: SHQ) announces that the Company will undertake a clinical
programme evaluating ADDERALL XR(R) in adolescents with attention deficit
hyperactivity disorder (ADHD), following receipt of a Written Request from the
US Food and Drug Administration (FDA).

FDA Guidance for Industry* indicates that one important effect of execution of
the clinical programme and acceptance of the submission of the study data would
be the addition of six months to the existing Hatch-Waxman marketing exclusivity
for ADDERALL XR, therefore extending it from October 2004 to April 2005.

The programme will evaluate the safety and efficacy of ADDERALL XR in adolescent
patients suffering from ADHD. This patient population has unique challenges as
they transition from children to young adults, challenges that may be
exacerbated by ADHD. To date, no well-controlled clinical study has specifically
evaluated ADDERALL XR in the adolescent population.



* FDA Guidance for Industry Qualifying for Pediatric Exclusivity Under Section
505A can be found at www.fda.gov/cder/guidance/index.htm. The extract below
refers to the statement made above:
`Pediatric exclusivity will attach to
exclusivity and patent protection listed in the Orange Book for any drug product
containing the same active moiety as the drug studied and for which the party
submitting the studies holds the approved new drug application. For studies
conducted on an unapproved drug, pediatric exclusivity will also attach to any
exclusivity or patent protection that will be listed in the Orange Book upon
approval of that unapproved drug.'


For further information please contact:

Global (outside US and Canada)

Gordon Ngan - Investor Relations                           +44 1256 894 160

Jessica Mann - Media                                       +44 1256 894 280

US & Canada

Gordon Ngan - Investor Relations                           +44 1256 894 160

Michele Roy - Media                                        +1 450 978 7938



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Notes to editors

Over 28 million prescriptions have been written for the ADDERALL brand since its
launch. The newest product in this franchise, ADDERALL XR, is a once-daily
formulation of mixed amphetamine salts, which was launched in November 2001, and
has become one of the most widely prescribed ADHD treatments in the US.

Further information on frequently asked questions about pediatric exclusivity
can be found at www.fda.gov/cder/pediatric/faqs.htm


Shire Pharmaceuticals Group plc

Shire Pharmaceuticals Group plc (Shire) is a rapidly growing international
emerging pharmaceutical company with a strategic focus on four therapeutic areas
- central nervous system disorders (CNS), gastrointestinal (GI), oncology, and
anti-infectives. Shire also has three platform technologies: advanced drug
delivery, lead optimisation for small molecules and Biologics. Shire's core
strategy is based on research and development combined with in-licensing and a
focus on key pharmaceutical markets.

For further information on Shire, please visit the Company's website:
www.shire.com

THE "SAFE HARBOR" STATEMENT UNDER THE PRIVATE SECURITIES LITIGATION REFORM ACT
OF 1995. Statements included herein that are not historical facts, are
forward-looking statements. Such forward-looking statements involve a number of
risks and uncertainties and are subject to change at any time. In the event such
risks or uncertainties materialise, Shire's results could be materially
affected. The risks and uncertainties include, but are not limited to, risks
associated with the inherent uncertainty of pharmaceutical research, product
development, manufacturing and commercialisation, the impact of competitive
products, including, but not limited to, the impact on Shire's Attention Deficit
Hyperactivity Disorder (ADHD) franchise, patents, including but not limited to,
legal challenges relating to Shire's ADHD franchise, government regulation and
approval, including but not limited to the expected product approval date of
lanthanum carbonate (FOSRENOL(R)) and METHYPATCH (R) , and other risks and
uncertainties detailed from time to time in our filings, including the Annual
Report filed on Form 10-K by Shire with the Securities and Exchange Commission.


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