Second Quarter Resultsended 30 June 2003and strategic review

Shire Pharmaceuticals Group plc

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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®) and METHYPATCH®, 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.

Trade mark Information:The following are trade marks of Shire or companies within the Shire Group, which are the subject of trade mark registrations in certain territories.ADDERALL XR® (mixed amphetamine salts), ADDERALL® (mixed amphetamine salts), AGRYLIN® (anagrelide hydrochloride), AMATINE® (midodrine hydrochloride), CALCICHEW® (calcium carbonate), CARBATROL® (carbamazepine), COLAZIDE® (balsalazide), DEXTROSTAT® (dextroamphetamine salt), EMUTROL™, ENSOTROL®, FARESTON™ (toremifene)FLUVIRAL® S/F (split-virion influenza vaccine), FOSRENOL® (lanthanum carbonate), METHYPATCH® (methylphenidate), MICROTROL®, MICROTROL DR™, MICROTROL PR™, MICROTROL XR™, OPTISCREEN®, PROAMATINE® (midodrine hydrochloride), PROSCREEN™, RAPITROL™, SOLARAZE® (diclofenac sodium 3%), SOLUTROL™, TROXATYL® (troxacitabine), XAGRID® (anagrelide hydrochloride).The following are trade marks of third parties: 3TC (lamivudine) (trade mark of GlaxoSmithKline (GSK)), ADEPT (4% icodextrin solution) (trade mark of ML Laboratories plc), AZT (trade mark of GSK), BIO-HEP B (trade mark of Berna Biotech AG), COMBIVIR (trade mark of GSK), EPIVIR (trade mark of GSK), HEPAVAX GENE (trade mark of Berna Biotech AG), NEISVAC-C (trade mark of Baxter International Inc.), PENTASA (trade mark of Baxter International Inc.), REMINYL (galantamine hydrobromide) (trade mark of Johnson & Johnson), TRIZIVIR (trade mark of GSK), ZEFFIX (lamivudine) (trade mark of GSK), Concerta (trade mark of Johnson & Johnson), Metadate CD (trade mark of Celltech), Ritalin LA (trade mark of Novartis), Strattera (trade mark of Eli Lilly), Focalin (trade mark of Novartis), ASACOL (trade mark of Procter & Gamble).

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Agenda

Overview Matthew EmmensQ2 Financial highlights

Strategic review and actions

Financial Review Angus RussellR&D Review Wilson TottenSummary Matthew EmmensQuestions & Answers All

Shire Pharmaceuticals Group plc

Matthew Emmens – Chief ExecutiveOverview: Q2 highlightsStrategic review and actions

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Millions of USD, except per share amounts

Q2 2003Q2 2003

RevenuesRevenues 299.0299.0Operating incomeOperating income 94.294.2Income before taxIncome before tax 92.192.1Net incomeNet income 65.565.5

EPS (diluted):EPS (diluted):Ordinary sharesOrdinary shares 1313ADSADS 3838

+ 21%

Financial Highlights – Q2 2003

+ 10%

+ 25%

Growth overGrowth overQ2 2002Q2 2002

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Strategic Review

Opportunities:Effective specialty physician model

Attractive late stage projects – CNS, GI, and renal

Strong balance sheet – cash

Experience in M&A

ChallengesLoss of marketing exclusivity and generic challenges

R&D budget demands for the broad portfolio

Relatively complex infrastructure

Comprehensive review of the challenges and opportunities:

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Strategy

Key components:Target customers – specialty physicians in US, Canada and Europe

Focus R&D activity – enable fuller funding of fewer, later stage, lower risk projects in CNS, GI and renal disease

Enhanced M&A effort (US emphasis and larger scale transactions)

Site rationalization / operational improvements

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Immediate Actions

High level M&A team

Intention to spin off the vaccines business

Close early stage R&D

Exit oncology R&D, out-license TROXATYL

Seek partnership for SPD754 (HIV) – continue development

Shire Pharmaceuticals Group plc

Angus Russell – Group Finance DirectorSecond Quarter 2003 Financial Review

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Millions of USD, except per share amounts

Financial Highlights – Q2 2003

Q2 2003

Revenues 299.0Operating income 94.2Income before tax 92.1Net income 65.5

EPS (diluted):Ordinary shares 13ADS 38

+ 21%

+ 10%

+ 25%+ 19%+ 10%

Differential growth rates influenced by:

Investment write-downs, fx

Discontinued operations, tax,and equity method investees

R&D spend

11

30

41

19

86

14

Q2 02(%)

32

42

17

84

16

Q2 03(%)

29

43

18

85

15

Q1 03(%)

32Operating margin

38

18

84

16

FY 02(%)

R&D : Revenues

S,G&A (excl. D&A) : Product sales

Gross margin

COGS : Product sales

Financial Ratios

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+1+1112.613.9Carbatrol

+8+2429.436.6Agrylin

-3+1521.524.8Pentasa

+12+6810.918.3ProAmatine

+17

-32

+35

Growth (%)

+16104.1121.6Adderall Brand

-5928.319.2Adderall

+6275.8102.4Adderall XR

US Rx Growth (%)*

Q2 02Q2 03

Millions of USD

Product Sales – Q2 2003

* Source: IMS Data

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* Underlying sales growth expressed in constant exchange rates** Includes Reminyl

--

--

+ 15

+ 10

Underlying Growth (%)*

+ 628.6Other**

Reported Growth (%)

Q2 03 Royalties

+ 2851.8Total

+ 275.7Zeffix

+ 2237.53TC

Millions of USD

Royalty Income – Q2 2003

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Cash Flow – Q2 2003

Millions of USD

Net cash deficit for Q2 2003 : - $89M

Cash generation + $25

Tax / interest- $24

Products- $25

Fixed assets - $14

Financing- $51

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* Cash, cash equivalents, and marketable securities

1,290

896

1,647

31.03.03

1,185

807

1,713

30.06.03

1,214

806

1,573

31.12.02

Gross cash*

Net cash

Net assets

Balance Sheet

Millions of USD

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Strategic Review Financial Impact

Close down of Lead OptimisationClosure during Q3 2003Around 120 jobs affectedClosure charge of approx. $12 million, mainly in Q3 2003Closure costs net of savings around $7 million in FY 2003 (3 cents/ADS)Ongoing savings approx. $15 million per annum

Intention to spin-off the vaccines businessBy end H1 2004Deal structure to be finalized during Q3 2003First half 2003 operating loss of $14.5 million, inclusive of R&D costs of $7.8 million

Troxatyl To be out-licensedSavings to be re-invested in other late stage (Phase III) projects

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Full year 2003 Guidance

Revenue growth Mid to high teens

Operating margin Circa 30%

EPS growth (per ADS) High single to low double digit*

FY 2003 Financial Outlook

* Excludes closure of Lead Optimisation Business - impact of approximately 3 cents

Shire Pharmaceuticals Group plc

Wilson Totten – Group R&D DirectorR&D Overview

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R&D Portfolio FocusP/C and Phase I Phase II / III / Reg In Market R&D Support

Troxatyl AMLTroxatyl Pancreatic

Xagrid Agrylin

SPD473SPD483SPD465

SPD503Methypatch

Carbatrol Bipolar

ReminylAdderall XR

Carbatrol

SPD476SPD480

Pentasa 500mg

PentasaColazide

Fosrenol ProAmatineAdept

SPD756 (HIV) SPD754 (HIV) 3TC

SPD707 (Flu T-) Fluviral SPD701 (Flu)

SPD703 (S.pneu)SPD704 (N.menin)SPD705 (P.aeru)

Haematology

CNS

GI

Other

Anti-viral

SPD451

Continue R&D

Out-license / Exit

Legend:

Haematology

CNS

GI

Other

Anti-viral

Oncology

Vaccines

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Adderall XRFormulation patent to 2018Hatch-Waxman to Oct 2004Paediatric Extension programme agreed with FDA

Should extend Hatch-Waxman to April 2005Adult ADHD indication, on approval, qualifies for 3 year Hatch-Waxman

CarbatrolFormulation patents to 2011 and 2016Bipolar programme progressing well, filing H1 2004On approval, 3 years Hatch-WaxmanPlanning approach to strengthen protection of Bipolar indication

Exclusivity position for marketed drugs

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Agrylin / XagridUS orphan status expires March 2004Paediatric exclusivity programme agreedShould extend exclusivity to Sept 200410 year orphan status in EU from approval (2003)

ProAmatineOrphan status expires Sept 2003

PentasaPatent expiredGenericisation complex (topical Rx)High strength 500mg to be filed 2004Bridge to SPD476 (File 2005)

Exclusivity position for marketed drugs

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Key project updates

Fosrenol3 year clinical data recently presented – good efficacy and safetyWork ongoing to address remaining regulatory questionsNo new issues

Adderall XR AdultReview underwayFDA PDUFA date end Oct 2003

MethyPatchIn collaboration with Noven, addressing outstanding questions

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Key project updates (contd)

Xagrid EUPositive CPMP opinion receivedEU - wide approvals to follow

SPD476 (Ulcerative Colitis)Good clinical results presented previously (Q1 results)On schedule for Phase III H2 2003

SPD754 (HIV)Proof of Concept study recently presentedLog reduction in viral load up to 1.65 with 10 days therapyHighly effective, combined with excellent resistance profile

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RegistrationPhase 3Phase 2

R&D Key Project Progressions 2003/2004

XAGRID (EU)FOSRENOL

SPD503 (ADHD) 2005

METHYPATCH (ADHD)ADDERALL XR (adult)

CARBATROL (bipolar) H1 2004

Pentasa 500mg (UC) H1 2004

SPD476 (UC) H2 2003 2005

SPD480 (UC) 2006H1 2004

SPD473 (ADHD) H2 2003 2007

SPD754 (HIV) 2006

Shire Pharmaceuticals Group plc

Matthew Emmens – Chief ExecutiveSummary

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Summary

Strong quarterly resultsStrategy recognizes challenges aheadStrong balance sheet and substantial cashEnhanced M&A effort Refocused R&DOperating efficienciesPositioned for continued growth

Shire Pharmaceuticals Group plc