October 3rd, 2013

Teresa, Multiple Sclerosis, United States

IR Thematic Call on Multiple Sclerosis

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Forward Looking Statements

This presentation contains forward-looking statements as defined in the Private Securities Litigation Reform Act of

1995, as amended. Forward-looking statements are statements that are not historical facts. These statements include

projections and estimates and their underlying assumptions, statements regarding plans, objectives, intentions and

expectations with respect to future financial results, events, operations, services, product development and potential,

and statements regarding future performance. Forward-looking statements are generally identified by the words

"expects", "anticipates", "believes", "intends", "estimates", "plans" and similar expressions. Although Sanofi's

management believes that the expectations reflected in such forward-looking statements are reasonable, investors are

cautioned that forward-looking information and statements are subject to various risks and uncertainties, many of which

are difficult to predict and generally beyond the control of Sanofi, that could cause actual results and developments to

differ materially from those expressed in, or implied or projected by, the forward-looking information and statements.

These risks and uncertainties include among other things, the uncertainties inherent in research and development,

future clinical data and analysis, including post marketing, decisions by regulatory authorities, such as the FDA or the

EMA, regarding whether and when to approve any drug, device or biological application that may be filed for any such

product candidates as well as their decisions regarding labeling and other matters that could affect the availability or

commercial potential of such product candidates, the absence of guarantee that the product candidates if approved will

be commercially successful, the future approval and commercial success of therapeutic alternatives, the Group's ability

to benefit from external growth opportunities, trends in exchange rates and prevailing interest rates, the impact of cost

containment policies and subsequent changes thereto, the average number of shares outstanding, as well as those

discussed or identified in the public filings with the SEC and the AMF made by Sanofi, including those listed under

"Risk Factors" and "Cautionary Statement Regarding Forward-Looking Statements" in Sanofi's annual report on Form

20-F for the year ended December 31, 2012. Other than as required by applicable law, Sanofi does not undertake any

obligation to update or revise any forward-looking information or statements.

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Agenda

Key Highlights on Multiple Sclerosis Market

● Bill Sibold - Senior Vice President, Head of Multiple Sclerosis - Genzyme

Clinical Data Highlights

● Michael Panzara, MD, MPH - Therapeutic Area Head of MS & Neurology - Genzyme

Genzyme MS Global Launch Update

● Bill Sibold - Senior Vice President, Head of Multiple Sclerosis - Genzyme

Q&A Session

Multiple Sclerosis Market:

Key Highlights

Bill Sibold

SVP, Head of Multiple Sclerosis - Genzyme

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Global MS Market - Significant and Growing Market

Key Facts about MS

● Serious disease with significant

unmet medical needs

● Symptoms include fatigue,

weakness, walking and balance

difficulties, vision problems

● A major impact on family, social

and professional life

● ~2.1m patients worldwide(1)

● ~410,000 patients in the U.S.(1)

● ~630,000 patients in EU(2)

Multiple Sclerosis

(1) National Multiple Sclerosis Society

(2) http://msj.sagepub.com/content/18/5/628.full.pdf

(3) Adapted from Evaluate Pharma July 2013; Reported sales of Copaxone®, Avonex®, Rebif®, Betaseron/Betaferon®, Extavia®,

Tysabri® and Gilenya® for 2012; 2007 sales converted using €/$ of 1.37, 2012 sales and 2017e sales converted using €/$ of 1.29

Multiple Sclerosis Market

Global Sales(3)

2012

2017e

U.S.

ROW

~€11bn

>€14bn

2007

~€5bn

~40% ~60%

2012-17 growth driven by new therapies, satisfying the unmet

needs of convenient administration and more efficacious therapy

~50% ~50%

MS Market in a State of Transition Presents Opportunities

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Multiple Sclerosis Market Features

Today

● 7 Mechanisms of Action

● 10 Marketed Products

● 3 Modes of Administration

● Greater Treatment Urgency

In 2005

● 2 Mechanisms of Action

● 4 Marketed Products

● 1 Mode of Administration

● More Acceptance of Disease Activity

Increasing diversity of therapeutic options

allowing a more individualized treatment approach

7

MS Treatment Options Have Increased:

Oral and Intravenous Products Share Has Grown

Evolution of MS Market

(1) Company reported sales of Avonex®, Betaseron®/Betaferon®, Copaxone®, Rebif® and Tysabri ® converted using €/$ rate of 1.33

(2) Company reported sales of MS products in H1 2013. Aubagio®, Betaseron®, Copaxone®, Rebif® converted using €/$ rate of 1.31

(3) Injectable therapies include Avonex®, Betaseron®/Betaferon®, Copaxone®, Rebif®, Extavia®

(4) Intravenous therapies include Tysabri®

(5) Oral therapies include Aubagio®, Gilenya® and Tecfidera®

74%

15%

Total Half Year Sales

€5.9bn

H1 2007(1) H1 2013(2)

Total Half Year Sales

€2.4bn

Orals(5)

Intravenous Therapies(4)

Injectable Therapies(3)

11%

96%

4%

8

● Oral therapy(2) share projected to

increase four-fold to nearly 40% of

the MS market by 2017 driven by

new entrants

● Intravenous therapies(3) expected to

approach 20% of the market

● Injectable therapies(4) (ABCRE’s)

projected to decline by roughly half

of current usage by 2017

(1) Evaluate Pharma July 2013

(2) Oral category includes Aubagio®, Gilenya®, Tecfidera®, laquinimod, 2nd Gen S1Ps

(3) Intravenous category includes Tysabri®, Lemtrada®, ocrelizumab, daclizumab

(4) Injectable category includes Avonex®, Betaseron/Betaferon®, Copaxone®, Rebif®, Extavia®, Plegridy™

Transition to Oral and Intravenous Therapies

Expected to Continue

59%

0%

15%

30%

45%

60%

75%

90%

2012 2017e

MS Market Evolution(1,2,3,4)

(% market share)

Injectables

Intravenous

Orals

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Michael Panzara, MD, MPH

Therapeutic Area Head of MS & Neurology - Genzyme

Clinical Data Highlights

Multiple Sclerosis Results in Significant Brain Injury with

Irreversible Consequences

42 years-old 52 years-old

Brain MRI Reveals Significant Progression of Atrophy Over 10 Years(1)

(1) Courtesy of Beth Fisher and Rick Rudick Cleveland Clinic 10

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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(1) O’Connor PW et al. N Engl J Med 2011;365:1293-1303

(2) Adjusted for Expanded Disability Status Scale score strata and region at baseline and takes duration of treatment

into account

(3) Kappos L et al. Mult Scler J 2012;18:(S4)9-53(153)

Once-Daily Oral Therapy with Robust Efficacy

TEMSO STUDY(1) TOWER STUDY(3)

Annualized Relapse Rate(2)

Placebo

- 36.3% p=0.0001

- 31.5% p=0.0005

Aubagio® 14mg

n=370

Placebo Aubagio® 14mg

0.539

0.319 0.369

0.501

n=363 n=358 n=388

Annualized Relapse Rate(2)

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(1) O’Connor PW et al. N Engl J Med 2011;365:1293-1303

(2) At Week 108

(3) Derived using Cox proportional hazard model with treatment, EDSS strata at baseline and region as covariates

(4) Derived from log-rank test with stratification of EDSS strata at baseline and region

(5) Kappos L et al. Mult Scler J 2012;18:(S4)9-53(153)

Only Oral Therapy to Show Significant Effect

on Disability in Two Phase III Trials

TEMSO STUDY(1) TOWER STUDY(5)

Reduction in Progression of

Disability(2)

Placebo

-29.8%(3) p=0.0279(4)

Aubagio® 14mg

Placebo Aubagio® 14mg

0.273

0.158

0.202 0.197

-31.5%(3)

p=0.0442(4)

Reduction in Progression of

Disability(2)

n=363 n=388 n=370 n=358

TEMSO(1) TEMSO Extension Study(2)

0.171 0.177

0.369

0.539

14mg/

14mg

Placebo/

14mg 14mg Placebo

Annualized Relapse Rate Annualized Relapse Rate

Long-term Efficacy and Safety Supported

by TEMSO Extension Trial

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

into account

(2) Freedman, M et al. Mult Scler J 2013; 19:(S1)74-558

● TEMSO extension trial included

patients receiving Aubagio® for

up to 9 years (up to 7 years

extension treatment)

● No new or unexpected safety

signals emerged during the study

● Measured clinical and MRI

disease activity remained low in

patients continuing on study

treatment

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Similar Incidence of SAEs Among Aubagio®

and Placebo-treated Patients in Clinical Trials

● The Aubagio® label(1) includes:

● Risk of teratogenicity (based on animal data)

and hepatotoxicity

● ALT elevations

● Alopecia

● Diarrhea

● Influenza

● Nausea

● Paresthesia

SAE: Serious Adverse Event

(1) Adapted from U.S. Prescribing Information and European SmPC

Relative Proportion of T Cells

Increased with T-Reg Phenotype(2)

Months on Therapy

Potentially Rebalances the Immune System

● Selectively targets CD52

protein, depleting B and T cells

responsible for MS inflammatory

process

● A distinctive pattern of

lymphocyte repopulation occurs

over time(1)

● May reduce inflammatory

processes in MS and have

disease modifying effects

● Supported by durable efficacy

after two short treatment

courses

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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, Jones JL et al. Brain 2010;133:2232-47

(2) Hartung HP et al. Mult Scler J 2012; 18:(S4)279-508

CD

4 T

reg

Cell C

ou

nts

(%

)

Lemtrada® 12 mg/day

Rebif®

Lemtrada® has been granted marketing authorization by the European Commission and is under review by the

regulatory authorities in the U.S. The mechanism by which it exerts therapeutic effect in multiple sclerosis is unknown.

Lemtrada® is developed in collaboration with Bayer HealthCare

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CARE-MS I(1) CARE-MS II(2)

Randomized Patients 581 840

Study Duration 2 years 2 years

Patient

Population Treatment

naïve

Relapsed on

prior treatment

Treatment

Arms

Lemtrada®

vs. Rebif®

Lemtrada®

vs. Rebif®

Active Comparator Set High Bar for Success

(1) Coles AJ et al. Lancet. 2012;380(9856):1829-1839

(2) Cohen JA et al. Lancet. 2012;380(9856):1819-1828

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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®

- 49% p<0.0001

CARE-MS I(1) CARE-MS II(2)

Annualized Relapse Rate

Annualized Relapse Rate

Significant Comparative Efficacy Results

with Unique Annual Dosing Regimen

Lemtrada®

(1) Coles AJ et al. Lancet. 2012;380(9856):1829-1839

(2) Cohen JA et al. Lancet. 2012;380(9856):1819-1828

HR: Hazard Ratio

SAD: Sustained Accumulation of Disability

(1) CARE-MS I study in treatment-naïve patients did not show a significant reduction in sustained accumulation of disability

(2) Cohen J et al. AAN 2012:platform presentation of CARE-MS II.

Time to SAD(1,2)

CARE-MS II

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21.1%

12.7%

Rebif®

Lemtrada®12 mg/day HR 0.58

Treatment effect: 42%

p=0.0084

Slowed Accumulation of Disability vs. Rebif®(1)

Pe

rce

nta

ge

of

Pa

tie

nts

wit

h S

AD

Improvement in Pre-Existing Disability:

6-Month Sustained Reduction in Disability

6-Month SRD

CARE-MS II(2)

Follow-up Month

0

3 15 18 21 24 12

Pe

rce

nta

ge o

f P

ati

en

ts w

ith

SR

D

10

40

6 9 0

30

20

HR: 2.57

p=0.0002

28.8%

12.9%

50 Rebif®

Lemtrada®12 mg

20

● Data suggests that improvement

in pre-existing disability was

more likely with Lemtrada® than

Rebif® regardless of which

functional system was impaired

by prior MS disease activity(1)

● All functional systems contributed

to EDSS improvement(1)

RRMS: Relapse Remitting Multiple Sclerosis

(1) Brinar, V ECTRIMS 2013 (P649)

(2) Cohen J AAN 2012:platform presentation of CARE-MS-II

Durable Effect on Sustained Reduction

in Disability Through Year 3

21 (1) Hartung HP ECTRIMS 2013(P592)

6-Month SRD(1)

CARE-MS II Extension Study ● More than 1/3 of Lemtrada®

treated patients in CARE-MS II

extension study attained

sustained disability improvement

by Year 3

● Approximately 80% of patients did

not receive re-treatment during

Year 3

● Fewer than 3% received another

disease modifying treatment in

Year 3

29%

35%

0 6 12 18 24 30 36 0

10

20

30

40

50

Follow-up Month

Pe

rce

nta

ge o

f P

ati

en

ts w

ith

SR

D

Safety Experience

from MS Development Program

● Infusion-associated reactions very common

● Premedication reduced/alleviated symptoms

● Infections common in both groups

● More common with Lemtrada®, low number of serious events

● Autoimmune events, some serious

● Detected via risk management plan allowing early diagnosis and treatment

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Significant Global Regulatory Milestones Achieved

RRMS: Relapse Remitting Multiple Sclerosis

(1) Not indicated for treating non-active patients and those stable on therapy

● EU approved for adult patients with RRMS ● New Active Substance designated by

EMA providing 10 years of data exclusivity in the EU

● FDA approved for adult patients with relapsing forms of multiple sclerosis

● Also approved in Australia, Mexico, Argentina, Chile, South Korea

● EU approved for patients with RRMS with active disease as defined by clinical or imaging features(1)

● FDA decision expected in late

Q4 2013

● Regulatory reviews ongoing

in several other regions

Global Launch Update

Bill Sibold

SVP, Head of Multiple Sclerosis - Genzyme

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Genzyme’s Critical Success Factors in MS

Products People Approach

● Lemtrada® and Aubagio®

are highly differentiated

novel products

● Fulfill unmet needs

● Well positioned for an

evolving market

● Accomplished team

● Leveraging experienced

Sanofi MS sales reps in

European countries

● Strong commitment and

relationships

● Science driven and

patient focused

● Long term partners

● Be leaders

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Cumulative U.S. Weekly TRx(1)

Encouraging U.S. Launch Trends

(1) IMS Weekly Total Prescriptions

(2) Q3 2013 Aubagio® quarterly sales figure is an estimate to be validated when company earnings are released

on October 30, 2013

Aubagio®: Quarterly Sales

Week 48 Week 1

60,000 Tecfidera®

Gilenya®

Aubagio®

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Q4 2012 Q2 2013 Q1 2013

€7m

€20m

€33m

Tecfidera® Launch

€44m(2)

Q3 2013e

40,000

20,000

Broad Based Patient Demand

DMT: Disease Modifying Therapy

(1) Based on data collected at Genzyme's MS One to One™ Patient and Provider Support Center, Sep 2012-Sep 2013

(2) BioTrends Research Group, LaunchTrends®: Aubagio® (teriflunomide) - Multiple Sclerosis (Wave 3) 2013

Aubagio® Prior Therapy(1) (Enrolled Patients)

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● ~20% patients prescribed

Aubagio® were treatment-

naïve(2)

● >80% of patients switched to

Aubagio® were most recently

on ABCR’s

● Most frequently cited reasons

for initiating Aubagio®(2)

● Oral administration

● Once-daily dosing

● Needle Fatigue/Phobia

30.6%

22.0%

14.1%

3.9%

17.4%

8.5% 1.3%

Other

2.2%

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Launching a Global MS Franchise(1)

(1) Timing of regulatory approvals and country reimbursement policies may impact projected launch timelines

2012 Selected Markets 2014

2012 Selected Markets 2014

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Ready to Launch Our MS Franchise in the EU

Aubagio®

and Lemtrada®

approved

Field forces

hired and

trained

Patient support

infrastructure

and programs

in-place

First product

shipments

First EU sales

in October

2013

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● Multiple Sclerosis market is significant and growing

● New therapies, satisfying the unmet needs of convenient

administration and increased efficacy, to drive growth

● Genzyme uniquely placed to seize opportunities in

Multiple Sclerosis

● Multiple Sclerosis team with proven track record

● Aubagio® and Lemtrada® are positioned for success

in an evolving market

Committed to Being Leaders in MS

Q&A SESSION

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