Bernstein Strategic Decisions Conference

Jérôme Contamine, CFO

London, September 19th, 2012

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

Sanofi - Transforming into a Global Healthcare Leader

2005-2008 2009-2011 2012 onwards

Focusing on Rx Blockbusters Transforming

Generating Sustainable Growth

• Investing in growth platforms • Increasing diversification • Managing patent cliff

• Growing recurring sales • Improving risk profile

• Blockbuster drugs • Patents challenged • R&D setbacks

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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

4 4

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

9 (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

Merial Sales Growth Showed Strong Rebound in Q2 2012

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Q12010

Q22010

Q32010

Q42010

Q12011

Q22011

Q32011

Q42011

Q12012

Q22012

576 ● Strong Q2 2012 sales of €576m,

up +9.1% at CER

● Companion Animals segment sales of €385m, up +10.1% at CER ● Good Frontline® sales performance

● Velcera recently enjoined from selling their generic combination (fipronil + methoprene) in the U.S.(1)

● Production Animals segment sales of €191m, up +6.9% at CER ● Swine presence enlarged by recent

acquisition of Newport

(1) Merial was granted a preliminary injunction motion on June 29, 2012 against Velcera.

496 524

Quarterly Sales (€m)

Multiple Regulatory Milestones Expected in H2 2012

hoFH: Homozygous Familial Hypercholesterolemia heFH: Heterozygous Familial Hypercholesterolemia 16

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

FDA Approval on 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.

17 (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

An Exciting New Oral Treatment Now Approved by FDA for Relapsing MS

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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) 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) TEMSO and TOWER. Analysis of the full TOWER data is ongoing and results will be presented at a forthcoming scientific meeting (6) The most frequent adverse reactions for AUBAGIO® in the placebo-controlled studies were ALT increased, alopecia, diarrhea, influenza, nausea, and paresthesia.

The AUBAGIO® label includes a boxed warning citing the risk of hepatotoxicity and teratogenicity (based on animal data).

● Aubagio® 14mg is the first oral to show significance on disability in two Phase III studies(5)

● Aubagio® 14mg provides “interferon-like” efficacy on Annualized Relapse Rate

● Well-characterized safety profile across placebo-controlled trials(6)

● Convenient once-daily oral dosing

TEMSO STUDY TOWER STUDYReduction in Progression of

Disability(2)

Placebo

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

Aubagio®

14mgPlacebo Aubagio®

14mg

0.273

0.1580.202 0.197

-31.5%(3)p=0.0442(4)

Reduction in Progression of Disability(2)

n=370n=363 n=359 n=388

TEMSO STUDY TOWER STUDYAnnualized Relapse Rate(1)

Placebo

- 31.5%p=0.0005

Aubagio®

14mg

n=370

Placebo Aubagio®

14mg

0.539

0.3190.369

0.501

n=363 n=359 n=388

Annualized Relapse Rate(1)

- 36.3%p=0.0001

2012 BOI Will Reflect Loss of Exclusivity of Plavix® and Avapro® in the U.S.

€m Q2 2012 Q2 2011 % Change (reported €)

% Change (CER)

Net sales 8,870 8,349 +6.2% +0.4%

Other revenues 247 422 -41.5% -45.7%

Cost of sales (2,730) (2,588) +5.5% +2.4%

Gross profit 6,387 6,183 +3.3% -3.5%

R&D (1,239) (1,197) +3.5% -1.2%

SG&A (2,289) (2,268) +0.9% -4.3%

Other current operating income & expenses (152) 7 - -

Share of Profit/Loss of associates 122 278 -56.1% -60.1%

Non controlling interests (50) (58) - -

Business operating income 2,779 2,945 -5.6% -13.6%

Business operating margin 31.3% 35.3% - -

19 CER: Constant Exchange Rates

Tight Cost Control

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Cost of Sales (%)

Q12011

Q22011

Q32011

Q42011

Q12012

Q22012

32.0%31.5%31.0% 30.7%30.4% 30.8%

● CoGS virtually flat ● Productivity enhancement

● Favourable currency impact compensating for product mix evolution

● R&D to sales ratio down 0.3% ● Significant investment

in late stage pipeline

● Ongoing transforming initiatives

● Significant improvement in SG&A to sales ratio ● Genzyme integration

synergies

● tight control of G&A expenses

Underlying Performance in H1 2012 Underpins our Confidence in our Ability to Deliver Sustainable Growth in a Post-Cliff Era

Solid sales growth excluding Key Genericized Products

Industry-leading performance in Emerging Markets

Continued focus on managing our cost base

BNI impact of Plavix® and Avapro® loss of exclusivity in the U.S. as expected

Confident in delivering on FY 2012 guidance despite challenging global environment

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2

3

4

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Continued Execution of Strategy Expected to Deliver Sustainable Growth 2012-2015

2012-2015 Sales CAGR

Diversified sources of growth

Scale in businesses with significant barriers to entry

Low small molecule patent exposure in mature markets(1)

Large Emerging Markets presence(2)

Potential new product launches(3)

Operating margin evolution

2012-2015 Business EPS CAGR

Increased dividend payout ratio(4)

(1) 2012 sales from chemical products exposed to patent expiry in the U.S., Japan and Western Europe over 2012/2015 (2) Based on 2015 internal estimates (3) Over 2012-2015 (4) Dividend to be paid in 2014

~6%

50% of 2013 results

Up to 18

38-40%

Rebounding

> Sales CAGR

At least 5%

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