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


5am ET 10am GMT


                Shire files legal suit against Barr Laboratories



Basingstoke,  UK - 3 September 2003 - Shire Pharmaceuticals Group plc (LSE: SHP,
NASDAQ:  SHPGY, TSX: SHQ) announces that its subsidiary Shire  Laboratories Inc.
has filed a lawsuit in the US District  Court for the  Southern  District of New
York  against  Barr   Laboratories  Inc.  ("Barr")  for  infringement  of  Shire
Laboratories' U.S. patent No. 6,605,300 ("the '300 Patent"), which was issued on
12th August 2003.

The lawsuit results from an ANDA  (Abbreviated  New Drug  Application)  filed by
Barr for a generic  version of ADDERALL  XR(R),  pursuant to which Barr provided
notice that it would seek to market its generic product before the expiration of
the '300 Patent in 2018.  ADDERALL  XR(R) is Shire's  leading  extended  release
Attention Deficit Hyperactivity Disorder ("ADHD") medicine.

Barr cannot launch a generic  version of ADDERALL XR(R) before it receives final
approval of its ANDA from the FDA.  The lawsuit  triggers a stay of FDA approval
of up to 30 months  from  Barr's  notice to allow the court to resolve the suit.
Even if Barr receives a final approval from the FDA, it cannot  lawfully  launch
its generic  version  before the earlier of expiration of the stay or a district
court decision in its favour.


                                      ENDS


For further information please contact:

Global (outside US and Canada)
Clea Rosenfeld - 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



Notes to editors



Shire Pharmaceuticals Group plc

Shire  Pharmaceuticals  Group plc (Shire) is a global  specialty  pharmaceutical
company with a strategic focus on meeting the needs of the specialist  physician
and  currently  has a range of  projects  and  products  in the areas of central
nervous  system (CNS),  gastrointestinal  (GI),  and renal  diseases.  Shire has
operations in the world's key  pharmaceutical  markets (US, Canada,  UK, France,
Italy, Spain and Germany) as well as a specialist drug delivery unit in the US.

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  materialize,  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  commercialization,   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)),  METHYPATCH(R),  XAGRID(R)  and  the  adult
indication  for ADDERALL XR(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.