IR Thematic Call on Multiple Sclerosis

April 25th, 2012

Jannan, MS

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Forward Looking Statements

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does not undertake any obligation to update or revise any forward-looking information or statements.

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Agenda

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Key Highlights on Multiple Sclerosis Market & Genzyme

● Bill Sibold - SVP, Head of Multiple Sclerosis - Genzyme

● Michael Panzara, MD, MPH - Therapeutic Area Head of Multiple Sclerosis - Genzyme

Mechanism of Action of Lemtrada™

● Alasdair Coles, PhD, FRCP - University of Cambridge, UK - CARE-MS Steering Committee

CARE-MS Studies

● Jeffrey Cohen, MD - Cleveland Clinic, OH - CARE-MS Steering Committee

Q&A Session

Lemtrada™ is the trademark submitted to health authorities for the investigational agent alemtuzumab Aubagio™ is the trademark submitted to health authorities for the investigational agent teriflumomide

KEY HIGHLIGHTS

ON MULTIPLE SCLEROSIS MARKET

& GENZYME

Bill Sibold

SVP, Head of Multiple Sclerosis - Genzyme

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Global MS Market - Significant and Expected to Grow

Key Facts about MS

● ~2.1m patients worldwide(1)

● Prevalent in young women

(~2:1 female/male ratio)

● Life expectancy 5-10 years lower

than unaffected people

● A major impact on family, social

and professional life

● Symptoms include fatigue,

weakness, walking and balance

difficulties, vision problems

Multiple Sclerosis

(1) National Multiple Sclerosis Society

(2) 2011: Reported sales of Copaxone®, Avonex®, Rebif®, Betaseron/Betaferon®, Extavia®, Tysabri®, and Gilenya®

(3) 2016e: Adapted from Evaluate Pharma report - December 2011

Multiple Sclerosis Market

Global Sales(2,3)

CAGR >6%

2011 2016e

U.S.

ROW

56%

54%

44% 46%

$12.5bn

$17.8bn

Key Facts about MS MS Therapies

Global MS Market - Still Dominated by ABCRE Products

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(1) ABCRE stands for Avonex®, Betaseron®/Betaferon®, Copaxone®, Rebif® and Extavia®

(2) Reported sales of ABCRE products plus Tysabri®, and Gilenya® in 2011

● “ABCRE” products(1) represented

84% of the global MS market in

value in 2011

● Moderate efficacy and patients

continue to relapse on therapy

● Require frequent injections

● Latest entrants represent

treatment alternatives

● Drives the benefit vs. risk

discussion

$3,884m

31%

$2,686m

21%

$1,553m

12%

$494m

4%

$2,350m

19%

$1,511m

12%

2011 Sales and

Market Share in Value(2)

$154m

1%

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- A Strong Commitment to MS

● Experience in developing

innovative treatments for

chronic disease

● Promising Multiple Sclerosis

clinical development program

● Extensive global relationships

with physicians, payers and

patient advocacy groups

Changing the

treatment paradigm

across the MS

spectrum of

disease

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Lemtrada™

Aubagio®

Rebif®

Lemtrada™

Aubagio™

(1) CIS – Clinically Isolated Syndrome, TOPIC Phase III study presently ongoing

(2) RRMS – Relapse Remitting Multiple Sclerosis

(3) RMS – Relapsing Multiple Sclerosis 8

Emergence of a Franchise Addressing

Individual Needs for People Living with MS

Unmet need 3

Efficacy with

manageable safety

Unmet need 2

Convenience,

efficacy & safety

Early MS/CIS(1) RRMS(2) and early active MS

RMS(3) severe/ highly active

Unmet need 1

Convenience

& safety

- Key Milestones for Genzyme MS Portfolio

● CARE-MS I Data Presentation

● CARE-MS II Data Presentation

● FDA & EMA Regulatory Submissions Expected Q2 2012

● TEMSO/TENERE Data Presentations

● FDA & EMA Regulatory Submissions

● TOWER Headline Results Expected Mid 2012

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Michael Panzara, MD, MPH

Therapeutic Area Head of MS - Genzyme

KEY HIGHLIGHTS

ON MULTIPLE SCLEROSIS MARKET

& GENZYME (cont’d)

New Treatment Goals - Focus on Patient Outcomes

Unmet Needs New Goals

Symptom Alleviation Decrease MS activity and improve quality

of life

Halt or reverse damage

and disability

Promote repair, remyelination, durable

disability improvement

Improve disease control Freedom from disease activity

Convenient treatment regimens

to improve compliance

Dosing options, new routes of

administration, less frequent dosing

Maximize patient outcomes Superior effectiveness and favorable

benefit/risk vs. existing treatment

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12 (1) Adjusted for Expanded Disability Status Scale score strata and region at baseline and takes duration of treatment into account

A Once-Daily Oral Therapy

with “Interferon-like” Efficacy

TEMSO STUDY TENERE STUDY

Annualized Relapse Rate(1)

Rebif®

p=ns

- 31.5% p=0.0005

Aubagio™ 14mg

n=104

Placebo Aubagio™ 14mg

0.539

0.259 0.369

0.216

n=363 n=359 n=109

Annualized Relapse Rate(1)

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Rebif®

- 55% p<0.0001

n=426

0.39

0.26

0.18

0.52

n=187 n=376 n=202

Lemtrada™ Rebif® Lemtrada™

- 49% p<0.0001

CARE-MS I CARE-MS II

Annualized Relapse Rate

Annualized Relapse Rate

Significant Comparative Efficacy Results

with Unique Annual Dosing Regimen

Only Therapy(1) Slowing Accumulation of Disability

Sustained for 6 months vs. Active Comparator

3 month

Active

Comparators

Placebo

6 month EDSS

Higher

Hurdle

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(1) Investigational compound

(2) Based on CARE-MS II

Higher

Hurdle

(2)

For Illustrative Purposes

Typical Threshold

for Approval

MECHANISM OF ACTION

OF LEMTRADA™

Alasdair Coles, PhD, FRCP

Department of Clinical Neurosciences,

University of Cambridge, UK

CARE-MS Steering Committee Member

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- Novel PK & PD Profile

● Humanized monoclonal antibody

● IV infusions administered in two courses: ● 12 mg daily on 5 consecutive days

in the first year

● 12 mg daily on 3 consecutive days 12 months later

● Serum concentrations of Lemtrada™ are low or undetectable within ~30 days following treatment

● Leads to immunomodulation through depletion and repopulation

16 (1) CARE-MS I data on file, Genzyme Corporation

–500

1500

4500

2500

3500

500

0

0 1 3 6 9 12 24 15 18 21 C

on

cen

trati

on

(n

g/m

L)

13

Months on Study

Serum concentrations(1)

- Selectively Targets Lymphocytes

● Selectively targets CD52

protein, depleting B and T

cells responsible for MS

inflammatory process

● B and T cell repopulation

begins within weeks and

continues over time(1)

● Other white blood cells are

minimally or transiently

affected(2,3)

● Protective serum antibodies

are unaffected(4)

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White Blood Counts in MS patients(5)

5.0

Neutrophils

Monocytes

Eosinophils

Basophils

Lymphocytes

0.0

0.5

1.0

1.5

2.0

4.0

4.5

0 1 2 3 4 5 6 7 8 9 10 11 12

Cell

Cou

nts

(1

09/L

)

Months after Alemtuzumab

(1) Coles AJ et al. AAN 2010; poster P06.172

(2) Hu Y et al. Immunology 2009;128:260-270, Turner MJ, et al. ECTRIMS 2011; poster 791

(3) Coles AJ et al, AAN 2012; platform S01.006

(4) Coles AJ et al. Lancet 1999;354:1691-5, McCarthy CL, et al. ECTRIMS 2011; poster 781

(5) CARE-MS I data on file, Genzyme Corporation

- Rebalancing the Immune System

● A distinctive pattern of

lymphocyte repopulation

occurs over time(1)

● May reduce inflammatory

processes in MS and have

disease modifying effects

● Increased production of

neurotrophic factors which

may promote neural repair

● Supported by up to three

years durable efficacy after

two short treatment

courses(2)

Increased % of T Cells

with T-Regulatory Phenotype(1)

Perc

en

tag

e o

f C

D4

+ T

Cells C

D25

hig

h

0

20

30

Healthy

Control

1 3 6 9 12

Time in months

10

*p<0.01

Pre-

treatment

*

*

*

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(1) Cox AL et al. Eur J Immunol 2005;35:3332-42., Hu Y et al. Immunology 2009;128:260-70, Havari E et al. ECTRIMS 2010; poster 424, Jones JL et al. Brain 2010;133:2232-47

(2) Coles AJ et al. NEJM 2008;1786-1801

CARE-MS STUDIES

Jeffrey Cohen, MD

Mellen Center, Cleveland Clinic,

Cleveland, OH

CARE-MS Steering Committee Member

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CARE - Comprehensive Study Program

CARE-MS I CARE-MS II

Randomized Patients 581 840

Study Duration 2 years 2 years

Patient

Population Treatment

naïve

Relapsed on

prior treatment

Treatment

Arms

Alemtuzumab

vs. Rebif®

Alemtuzumab

vs. Rebif®

CARE-MS Phase III program enrolled patients with relapsing-remitting multiple sclerosis

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CARE-MS I - Strong Effect on Relapse

Coles AJ ECTRIMS 2011; platform presentation

0.46 0.22 0.29 0.13 0.39 0.18

p=0.0002

p<0.0001

p=0.0002

p<0.0001

Rebif®

Lemtrada™ 12 mg/day

Relapse Rate by Year

- 55% p<0.0001

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CARE-MS I - Strong Effect on Relapse

Proportion of Relapse-Free Patients at Year 2

59%

78%

Lemtrada™ 12 mg/day

Rebif®

HR 0.45

P<0.001

Coles AJ ECTRIMS 2011; platform presentation

CARE-MS II - Strong Effect on Relapse

Cohen J AAN 2012: platform presentation

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0.59 0.42 0.52 0.28 0.25 0.26

p<0.0001

p=0.0017

Rebif®

Lemtrada™ 12 mg/day

Relapse Rate by Year

0.59 0.28 0.42 0.25 0.52 0.26

- 49% p<0.0001

HR: Hazard Ratio

SAD: Sustained Accumulation of Disability

Cohen J AAN 2012: platform presentation

Time to SAD

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21.1%

12.7%

Rebif®

Lemtrada™ 12 mg/day HR 0.58

Treatment effect 42%

p=0.0084

CARE-MS II - Slowing Accumulation of Disability

CARE-MS II - Reversing Disability in Some Patients

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Mean EDSS Change from Baseline

p<0.0001

0.24 p=0.0064

‒0.17 p=0.0044

Rebif®

Lemtrada™ 12 mg/day

EDSS: Expanded Disability Status Score

Cohen J AAN 2012; platform presentation

CARE-MS - Substantial Treatment Effect vs. Rebif®

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● Substantial treatment effect on relapse rate

● Meeting co-primary endpoint vs. active comparator in CARE-MS I & II

● Statistically significant difference in Time to 6-month SAD in CARE-MS II

● No statistical significant difference in CARE-MS I due to unexpected low rate

of sustained disability in comparator arm

● Patients treated with Lemtrada® in CARE-MS II were more than twice

likely to experience disability improvement over Rebif®

● Statistically significant treatment effect on other efficacy endpoints

in both CARE-MS I & II

SAD: Sustained Accumulation of Disability

CARE-MS Overview of Adverse Events (AE)

CARE-MS data on file, Genzyme Corporation

(1) This death was due to a motorcycle accident

(2) One death was due to a pedestrian accident and the other was due to an incident of aspiration pneumonia following a severe MS relapse

CARE-MS I CARE-MS II

Rebif®

SC INFB-1a

Lemtrada™

12 mg/day

Rebif®

SC INFB-1a

Lemtrada™

12 mg/day

(%) (%) (%) (%)

Adverse Events Patients with events

Infections

Thyroid Disorders

Immune Thrombocytopenia

AEs leading to treatment withdrawal

AEs leading to study discontinuation

92.0

45.5

6.4

0.5

5.9

2.7

96.0

67.3

18.1

0.8

1.3

0

94.6

66.3

5.0

0

8.9

3.0

98.4

76.8

15.9

0.9

3.2

0.2

Serious Adverse Events Patients with serious events

Serious Infections

14.4

1.1

18.4

1.9

21.8

1.5

19.5

3.7

Deaths 0 0.3(1) 0 0.5(2)

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CARE-MS - Well Characterized Safety Profile

● Infusion-associated reactions very common

● Premedication reduced/alleviated symptoms

● Infections common in both groups

● Predominantly mild to moderate, some serious

● Autoimmune events included thyroid disorders and immune

thrombocytopenia

● Detected via routine monitoring and generally managed using

conventional therapies

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29 CARE-MS data on file, Genzyme Corporation

● Ground-breaking efficacy results

● Treatment effects across multiple endpoints

● Manageable and consistent safety profile

● Monitoring program successful at early detection of AEs

● Favorable benefit/risk

● Convenient annual dosing

- A Transformative Approach to MS Treatment

Q&A SESSION

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