BofA-Merrill Lynch Healthcare Conference

Dr. Elias Zerhouni, President - Global R&D

London, September 12th, 2012

2

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, 2011. Other than as required by applicable law, Sanofi does not undertake any obligation to update or revise any forward-looking information or statements.

Growth Platforms Accounted for 64.9% of Group Sales and Grew by +7.6% in Q2 2012

5 (1) New Genzyme perimeter includes Rare Diseases and Multiple Sclerosis franchises (2) Multaq®, Jevtana® and Mozobil®

+13.7%

+3.0%

+11.3%

+9.1%

+9.1%

Innovative Products(2) €152m +4.5%

+9.8%

Vaccines €783m

Diabetes Solutions €1,436m

Consumer Health Care €738m

Animal Health €576m

Emerging Markets €2,823m

New Genzyme(1) €434m

Growth at CER

Executing Successful Strategy to Reposition Sanofi

Deliver sustainable growth

and generate improved

shareholder returns Adapt structure for future challenges and opportunities 3

Pursue external growth opportunities 2

Increase innovation in R&D 1

6 6

Multiple Regulatory Milestones Expected in H2 2012

hoFH: Homozygous Familial Hypercholesterolemia heFH: Heterozygous Familial Hypercholesterolemia 7

Zaltrap®, Kynamro™, Aubagio®, Lyxumia® and Lemtrada™ are registered trade names submitted to health authorities for investigational agents Zaltrap® is developed in collaboration with Regeneron, Kynamro™ with Isis Pharmaceuticals and Lyxumia® is in-licensed from Zealand Pharma

PDUFA: Prescription Drug User Fee Act CHMP: Committee for Medicinal Products for Human Use

Expected Milestones

FDA Approval on Aug 4th 2012 CHMP Opinion: Q4 2012

CHMP Opinion: Q4 2012 FDA Submission: Dec 2012

FDA Re-Submission as soon as possible CHMP Opinion: Q2 2013

Relapsing Forms of Multiple Sclerosis

PDUFA Date: Sep 12th 2012 CHMP Opinion: Q1 2013

Relapsing Forms of Multiple Sclerosis

Metastatic Colorectal Cancer

Type 2 Diabetes

CHMP Opinion: Q4 2012 PDUFA Date: Jan 29th 2013

hoFH/severe heFH in EU and hoFH in the U.S

Products Targeted Indications

®

®

®

TM

Now Available in the U.S.

8 (1) Van Cutsem, et al. Ann Oncol. 2011;22(suppl 5). Abstract O-0024 and presentation at: ESMO 13th WCGIC.

June 22-25, 2011; Barcelona, Spain.

Key Facts about MS

● A novel VEGF trap acting on multiple angiogenic targets

● Indicated in combination with FOLFIRI in mCRC patients resistant to or progressing on an oxaliplatin-containing regimen

● Significant improvement in Overall Survival demonstrated in the VELOUR study(1)

Oncology

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

A GLP-1 Agonist for A1c Control with a Unique Biological Profile

Lyxumia® is the intended trademark for lixisenatide. Lixisenatide is currently not approved or licensed anywhere in the world. Lixisenatide was in-licensed from Zealand Pharma A/S. (1) Except for the device intended for Japan (2 steps to maintenance dose with one pen) 16

Pronounced effect on postprandial glucose (PPG) levels

Favorable safety profile with low risk of hypoglycemic events

Once-daily injection, simple 1 step to maintenance dose, 1 pen per dose(1)

A Unique Profile:

®

T2D Patients Treated with Basal Insulin(1) (worldwide)

On basal insulin On basal insulin with controlled fasting

glucose control but A1c >7%

4 million on other

basal insulins(2)

4 million on Lantus®

4 million

T2D – Type 2 Diabetes A1C – HbA1c or Glycated hemoglobin (1) Adapted from IMS data (2) Includes all types of basal insulins

Clinical Development Designed to Support Use in Combination with Basal Insulin

®

17

Mono Mono Japan

Monotherapy

Placebo-controlled in OAD failure

M (metformin)

F1 (metformin)

M Asia (metformin)

S (sulfonylurea)

P (pioglitazone)

X vs. exenatide Active-controlled

L Asia

L Placebo-controlled on top of

basal insulin Duo 1

Phase III Program

Fix-Flex Device Has Been Developed for Joint Administration of Lantus® and Lyxumia®

● Convenience of a single injection per day coupled with possibility to adjust Lantus® dose

● Entering phases for industrialization, validation, usability and manufacturing

● Device expected to be available mid-2013 for Phase III initiation

+ ®

Lyxumia® is the intended trademark for lixisenatide. Lixisenatide is currently not approved or licensed anywhere in the world. 18

New Glargine Formulation with Unique Pharmacokinetics

● New glargine formulation: ● Unique flat PK/PD profile ● Lower injection volume

● Phase III trials ongoing in T2D high-dose insulin users(1)

● Targeting ~1,600 patients

● Second set of studies recently started

EDITION I T2D Patients Basal Bolus

EDITION II T2D Patients Basal + OAD

PK/PD – Pharmacokinetic/Pharmacodynamic OAD – Oral anti-diabetic drugs (1) ClinicalTrials.gov Identifier: NCT1499082 & NCT01499095

New Insulin Glargine Formulation Depot formation after subcutaneous injection

Schematic illustration

Lantus® New Glargine Formulation

19

Otamixaban: Providing Superior Outcomes while Simplifying Treatment during Interventional Procedures

● Despite current therapies, death, MI, and readmission rates remain high

● Otamixaban is the first IV direct and selective factor Xa inhibitor with quick onset/offset

● 27 to 42% risk reduction in ACS complications including death and MI in Phase Il(1)

● Phase III TAO study ongoing with results expected in Q2 2013

(1) The Lancet, Volume 374, Issue 9692, Pages 762 - 764, 5 September 2009 NSTE-ACS – Non-ST-Elevation Acute Coronary Syndrome, MI – Myocardial Infarction, UFH – Unfractionated Heparin

TAO Study

Moderate-to-high risk NSTE-ACS with planned early invasive strategy (n=13,220)

Primary endpoint: Death/Myocardial Infarction @ day 7

Otamixaban Regimen 2 (n=1,969)

Otamixaban Regimen 1 (n=1,969)

UFH + Eptifibatide (n=1,969)

R

24

Sponsor-blinded interim analysis

Eliglustat: a Novel Oral Therapy in Gaucher Disease(1)

● Potent, novel substrate inhibitor

● Convenience of oral therapy ● Eliminating challenges of

infusing patients

● Clinical profile expected to be similar to Cerezyme®

● 4-year Phase II data at WORLD congress in February 2012

● Phase III trials fully recruited

25

(1) Investigational drug (2) Patient from Phase II clinical trial WORLD – World Organization of Research on Lysosomal Diseases

December 2006 pre-treatment (18 years)

December 2009 3 years post treatment (21 years)(2)

26

Dengue Vaccine: Addressing a Growing Global Threat

First Efficacy Results

● Phase IIb results in ~4,000 patients recently published in the Lancet

● Effective against DENV 1, 3 and 4 (in the range of 60% to 90%), with only DENV 2 appearing to be resistant

● Safe and well-tolerated

Significant Disease Burden

● Estimated 220m dengue infections worldwide per year

● 2m cases of Hemorrhagic Fever

● >500,000 hospitalizations and >20,000 deaths / year

● Dengue: a public health priority in Asia and Latin America

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Ambitious Phase III Program

● Global Phase III program ongoing

● Large scale studies in LatAm and Asia

● 31,000 children and adolescents

● Results expected in 2014

Ensuring R&D Contributes to Sanofi’s Success

Global R&D

Goals

An efficient global R&D organization Maximize synergies and convergence around Hub model Exploit economies of scale Improve R&D cost structure

Focus on high-value projects

Execute on late-stage projects Medical value and translational feasibility to guide early-stage

portfolio prioritization

Establish new models of external innovation Enhance the value of external opportunities and partnerships Create open and creative models with partners across the

healthcare ecosystem

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APPENDICES R&D Pipeline

28

29

Late Stage Pipeline – Pharma & Vaccines

eliglustat tartrate Glucosylceramide synthetase inhibitor

Gaucher disease

otamixaban Direct Xa inhibitor

ACS

Quadracel® Diphtheria, tetanus, pertussis & polio vaccine; 4-6 y of age

Hexaxim® DTP-HepB-Polio-Hib vaccine

iniparib (BSI-201)

squamous NSCLC (1L)

lixisenatide (AVE0010) GLP-1 agonist

Type 2 diabetes, U.S.

Fluzone® QIV IM Quadrivalent inactivated

influenza vaccines

Plavix® clopidogrel bisulfate PAD, STEMI, Japan

ombrabulin (AVE8062) Vascular disrupting agent

Soft tissue sarcoma (2L/3L)

New formulation Insulin glargine

Type 1+2 diabetes

VaxiGrip® QIV IM Quadrivalent inactivated

influenza vaccines

teriflunomide Relapsing forms of multiple sclerosis

(RMS) – monotherapy, U.S. / EU

SAR302503 (TG101348) JAK-2 inhibitor

Myelofibrosis (1L)

mipomersen Apolipoprotein B-100 antisense

Severe HeFH, U.S.

alemtuzumab Anti-CD52 mAb

Multiple sclerosis, U.S. / EU

Jevtana®

Cabazitaxel Metastatic prostate cancer (1L)

SAR236553 Anti-PCSK-9 mAb

Hypercholesterolemia

Allegra® fexofenadine

Dry syrup, Japan

SYNVISC-ONE™

Medical device Pain in hip OA

sarilumab (SAR153191) Anti-IL-6R mAb

RA

mipomersen Apolipoprotein B-100 antisense HoFH and severe HeFH in EU;

HoFH in U.S.

MACI®

Cell-based treatment Articular cartilage defects

Dengue Mild-to-severe

dengue fever vaccine

lixisenatide (AVE0010) GLP-1 agonist

Type 2 diabetes, EU / Japan

teriflunomide Multiple sclerosis

(adjunct therapy & CIS)

DTP-HepB-Polio-Hib Pediatric hexavalent vaccine

aflibercept VEGF-Trap

2nd line mCRC, U.S. / EU

Registration Phase III

N

N

N N

N

N

N

N

29

N

N N

N

N New Molecular Entity Central Nervous System

Genetic diseases

Oncology Metabolic Disorders

Vaccines Internal Medicine

Biosurgery

Thrombosis

Aging Ophthalmology

Status as of July 26, 2012

Early Stage Pipeline – Pharma & Vaccines

iniparib (BSI-201)

Ovarian cancer (2L)

FOV1101 FDC prednisolone/cyclosporine

Allergic conjunctivitis

SAR231893 Anti-IL4 mAb

Asthma; Atopic dermatitis

SAR3419 Maytansin-loaded anti-CD19 mAb

B-cell malignancies refractory/relapsed (DLBCL, ALL)

safotibant (FOV2304) Bradykinin B1 antagonist Diabetic macular edema

ferroquine Antimalarial

Malaria

SAR256212 (MM121) anti-ErbB3 mAb

Breast cancer (2L, 3L)

SAR110894 H3 antagonist

Alzheimer's disease

fresolimumab TGFβ antagonist

Fibrosis

SAR245408 (XL147) Oral PI3K inhibitor

Endometrial cancer (1L)

SAR113945 IKK-β inhibitor Osteoarthritis

SAR97276 Antimalarial

Malaria

SAR245409 (XL765) Oral dual inhibitor of PI3K & mTOR

Breast cancer (1L)

SAR292833 (GRC15300) TRPV3 antagonist

Neuropathic pain, osteoarthritic pain

SAR279356 (F598) Anti-PNAG mAb Serious infections

ombrabulin (AVE8062) Vascular disrupting agent

Ovarian cancer (2L)

ACAM-Cdiff Clostridium difficile

Toxoid vaccine

SAR302503 (TG101348) JAK-2 inhibitor

Polycythemia vera (2L) Incyte (ruxolitinib) resistant/intolerant MF

Rabies VRVg Purified vero rabies vaccine

Jevtana®

Cabazitaxel, Microtubule inhibitor Small cell lung cancer (2L)

Meninge ACYW conj. 2nd generation meningococcal

Conjugate infant vaccine

Phase II

N

N

N

N

N

N

N

N

N

N

N N

N N

30 30

N New Molecular Entity Central Nervous System

Genetic diseases

Oncology Metabolic Disorders

Vaccines Internal Medicine

Biosurgery

Thrombosis

Aging Ophthalmology

Status as of July 26, 2012

31

Early Stage Pipeline – Pharma & Vaccines

SAR153192 Anti-DLL4 mAb

Solid tumors

SAR405838 (MI-773) MDM2 / p53 antagonist

Solid tumors and hematological malignancies

SAR252067 Anti-LIGHT mAb

Crohn’s disease & Ulcerative colitis

Rotavirus Live Attenuated Tetravalent

Rotavirus oral vaccine

GZ402674 Non-camptothecin topo1 inhibitor

Solid tumors

SAR127963 P75 receptor antagonist

Trauma brain injury

SAR339658 VLA 2 antagonist

Inflammatory Bowel disease

Streptococcus pneumonia Meningitis & pneumonia vaccine

SAR650984 Anti-CD38 naked mAb

Hematological malignancies

GZ404477 (AAV-hAADC) Gene therapy

Parkinson's disease

SAR100842 LPA-1/LPA-3

Skin manifestation of scleroderma

Pseudomonas aeruginosa Antibody fragment product

Prevention of ventilator-associated pneumonia

SAR566658 Maytansin-loaded anti-DS6 mAb

DS6 positive solid tumors

SAR391786 Rehabilitation post orthopedic surgery

SAR156597 IL4/IL13 Bi-specific mAb

Idiopathic Pulmonary Fibrosis

Tuberculosis Recombinant subunit vaccine

SAR307746 Anti-Ang2 mAb

Solid tumors

SAR228810 Anti-protofibrillar AB mAb

Alzheimer’s disease

SAR407899 Rho kinase inhibitor

Diabetic nephropathy

RetinoStat® Gene therapy

Wet age-related macular degeneration (AMD)

SAR125844 C-Met kinase inhibitor

Solid tumors

SAR399063 DHA-GLP + vit D Pre-sarcopenia

lixisenatide + Lantus® GLP-1 agonist + insulin glargine

Fix-Flex / Type 2 diabetes

StarGen® Gene therapy

Stargardt disease

Combinations SAR245409 / MSC1936369B

SAR245408/SAR256212 (MM121) Solid tumors

SAR404460 DHA-GPL + Vit D Pre-sarcopenia

SAR164653 Cathepsin A inhibitor

CV-related complications & deaths in diabetic patients

GZ402663 (sFLT-01) Gene therapy

Age related Macular Degeneration (AMD)

SAR393590 (Oral clofaribine) DNA synthesis inhibitor

Hematological malignancies

GZ402665 (rhASM)

Niemann-Pick type B

SAR126119 TAFIa inhibitor

Acute ischemic stroke

UshStat® Gene therapy

Usher syndrome 1B

Jevtana®

Cabazitaxel, Microtubule inhibitor Gastric cancer (2L)

Phase I N

N

N

N

N

N

N

N

N

N

N

N

N N

N

31

N

N

N

N

N

N

N New Molecular Entity Central Nervous System

Genetic diseases

Oncology Metabolic Disorders

Vaccines Internal Medicine

Biosurgery

Thrombosis

Aging Ophthalmology

N

N N

N

Status as of July 26, 2012

34

Expected R&D Milestones – Vaccines

34

Product Event Timing Shan5® Start of Phase III study Q3 2012

Fluzone® QIV IM Submission of regulatory file in the U.S. Q3 2012

HexaximTM Submission of regulatory file in EU Q3 2012

Fluzone® QIV ID Start of Phase III study Q4 2012

Vaxigrip® QIV IM Submission of regulatory file in EU Q1 2013

Fluzone® QIV IM Expected licensure in the U.S. Q2 2013

HexaximTM Expected licensure in EU and international countries Q2 2013