PRESS RELEASE Paris

Q2 2013: Last Quarter with Significant Negative Impact from the Patent Cliff

In order to facilitate an understanding of our operational performance, we comment on our business net income statement. Business net income(1) is a non-GAAP financial measure. The consolidated income statement for H1 2013 is provided in Appendix 4 and a reconciliation of business net income to consolidated net income in Appendix 3. Consolidated net income for H1 2013 was 1,448 million, compared to 2,962 million(2) for H1 2012. Consolidated EPS for H1 2013 was 1.09 versus 2.25(2) for H1 2012.

Commenting on the Group s performance in Q2 2013, Sanofi Chief Executive Officer, Christopher A. Viehbacher said, The second quarter was a difficult quarter. As expected, this was the last quarter with a tough comparison to the prior year due to the residual impact of the patent cliff. Sales were also affected by our business in Brazil(3) and commercial underperformance in certain business areas. However, sales growth of 7.7%(4) of our growth platforms(5) in the first half of 2013 continues to demonstrate the value of Sanofi s integrated business model. In addition, we keep on making strong progress in delivering a growing portfolio of high potential R&D assets, as highlighted by the multiple clinical and regulatory milestones reached in the second quarter of 2013. We continue to expect to return to growth in the second half of 2013.

Total sales(6) were 8,003 million, down 6.3% principally impacted by sales lost due to generic competition ( 481 million).

Sales in Emerging Markets(7) totalled 2,669 million, a decrease of 2.3% (+5.3% excluding Brazil generics); double-digit sales growth was achieved for Diabetes, Vaccines, Genzyme and Animal Health.

Diabetes delivered growth of 16.2% to 1,621 million as Lantus sales reached 1,409 million, an increase of 17.7%.

Consumer Healthcare sales were 729 million, an increase of 1.8%.

Vaccines sales reached 760 million (+0.4%) and compared to strong Q2 2012 sales which benefited from a later timing of flu vaccines supply in the Southern Hemisphere.

Animal Health sales were down 5.7% to 529 million impacted by unfavorable weather conditions and increased competition to Frontline .

Genzyme recorded another strong quarter with sales growth of 25.6% to 525 million, reflecting strong performance of the rare disease franchise and the progression of Aubagio .

Growth platforms(5) sales were 5,718 million, an increase of 2.5% (+6.2% excluding Brazil generics) and accounted for 71.4% of total sales.

Q2 2013 business EPS(1) was 1.11, down 18.5% impacted in particular by the Plavix and Avapro losses of exclusivity in the U.S. ( 0.18) and Brazil generics ( 0.17)(8).

Since publication of Q1 2013 results, several positive Phase III trials results have been announced including two Phase III trials for the investigational new insulin U300, and JAKARTA, which examined fedratinib, a selective JAK2 inhibitor, in myelofibrosis. In addition, the C. diff toxoid vaccine is now moving to Phase III.

Several major regulatory milestones were also achieved including positive recommendations from the CHMP both on Lemtrada and on a new active substance designation for Aubagio which is expected to lead to 10-year exclusivity and the FDA approval of the Fluzone Quadrivalent vaccine.

2013 Adjusted Guidance

Given the impact of Brazil and the year-to-date performance, 2013 business EPS is expected to be 7% to 10% lower than 2012 at CER(9), barring major unforeseen adverse events.

(1) See Appendix 8 for definitions of financial indicators; (2) Including impact of transition to IAS 19R; (3) See disclosure on page 2; (4) Excluding Brazil generics; (5) See page 2; (6) Growth in net sales is expressed at constant exchange rates (CER) unless otherwise indicated (see Appendix 8 for a definition); (7) See definition on page 7; (8) Operating losses, net sales adjustment and provisions; 0,19 at CER; (9) 2012 business EPS with the retroactive application of IAS19R was 6.14.

Investor Relations: (+) 33 1 53 77 45 45 - E-mail: IR@sanofi.com - Media Relations: (+) 33 1 53 77 46 46 - E-mail: MR@sanofi.com

Web site: www.sanofi.com

2013 second-quarter and first-half sales

Unless otherwise indicated, all sales growth figures in this press release are stated at constant exchange rates(1).

In the second quarter of 2013, Sanofi sales were 8,003 million, a decrease of 9.8% on a reported basis. Exchange rate movements had a negative effect of 3.5 percentage points primarily reflecting the depreciation of the Japanese Yen, U.S. Dollar, Venezuelan Bolivar, and the South African Rand against the Euro.

First-half sales reached 16,062 million, a decrease of 7.6% on a reported basis. Exchange rate movements had an unfavorable effect of 3.0 percentage points mainly driven by the depreciation of the Japanese Yen, U.S. Dollar, Venezuelan Bolivar, Brazilian Real, and the South African Rand against the Euro.

Second-quarter sales of the Group s growth platforms totaled 5,718 million, an increase of 2.5%, driven by the performance of Diabetes (up 16.2%), Genzyme (up 25.6%) and Other Innovative Products (up 14.5%). The Group s growth platforms accounted for 71.4% of total consolidated sales in the second quarter, up from 71.0% in the second quarter of 2012. Excluding Brazil generics, growth platforms grew 6.2% and Emerging Markets grew 5.3%.

During the second quarter, Sanofi determined that generic inventory levels in trade channels in Brazil were significantly and inappropriately in excess of volumes needed to satisfy sell out demand. Accordingly, an adjustment has been recorded in the current quarter to reflect product returns, customer discounts and rebates. The net effect of this adjustment was to lower net sales by 122 million. An additional provision of 79 million has also been recorded for the write-off of inventory and other related costs.

First-half sales of growth platforms reached 11,441 million, an increase of 5.4%, and accounted for 71.2% of total consolidated sales compared with 70.8% in the first half of 2012. Excluding Brazil generics, growth platforms were up 7.7%.

(a) Includes recent product launches which do not belong to the other Growth Platforms listed above: Multaq , Jevtana , Zaltrap , Auvi-Q and Mozobil

(b) World excluding the U.S. and Canada, Western Europe, Japan, Australia and New Zealand

(c) Excluding Brazil generics, sales in Emerging Markets grew 5.3% in Q2 2013 and 6.6% in H1 2013

In the second quarter, sales for the Pharmaceuticals business were 6,714 million, a decrease of 7.1%, which reflected generic competition, EU austerity measures and an adjustment of 122 million related to Brazil. Sales lost due to generic competition on main legacy products in the U.S. and EU were 481 million, primarily due to declining sales of Eloxatin , Lovenox and the active ingredient of Plavix in the U.S. and Aprovel in the EU.

First-half sales for the Pharmaceuticals business reached 13,522 million, a decrease of 5.7%. First-half sales lost due to generic competition on main legacy products in the U.S. and EU were 1,036 million.

(1) See Appendix 8 for definitions of financial indicators

Diabetes division sales totaled 1,621 million in the second quarter, an increase of 16.2%. Lantus sales grew 17.7% to 1,409 million driven by the U.S. (+20.9% to 903 million). In the U.S., Lantus SoloSTAR represented 56.4% of total Lantus sales in the quarter, versus 51.9% in the second quarter of 2012. In Emerging Markets, Lantus sales reached 230 million, an increase of 20.2% reflecting good performance in Russia, China, Africa and the Middle East. First-half sales of Lantus reached 2,747 million, up 19.4%.

In February 2013, the European Commission granted marketing authorisation for Lyxumia (lixisenatide, licensed from Zealand Pharma), a once-daily prandial GLP-1 receptor agonist. The launch of Lyxumia in the EU began with Germany at the end of the first quarter where the product has achieved 10.3% market share in volume after 18 weeks since launch(10). In the United Kingdom, the company is taking a step-wise approach by first obtaining local access followed by a full commercial launch later in the year. Commercialization in additional countries in the EU is expected in 2013. Second-quarter sales of Lyxumia were 1 million. In June 2013, Japan s Ministry of Health, Labour and Welfare approved the manufacturing and distribution of Lyxumia for the treatment of type 2 diabetes.

Apidra recorded sales of 68 million (up 25.0%) and 134 million (up 27.8%) in the second quarter and first half, respectively. This sales rebound reflects notably the resolution of temporary supply issues experienced last year.

Amaryl generated sales of 99 million (down 1.8%) impacted by generic competition in Japan where sales decreased 21.3% to 21 million. In Emerging Markets, Amaryl continued to deliver good performance (up 10.3% to 71 million). First-half, sales of Amaryl were 193 million (down 2.3%), of which 71.5% were generated in Emerging Markets ( 138 million) an increase of 10.8%.

The Diabetes division recorded sales of 3,163 million, an increase of 17.8% in the first half of 2013.

Second-quarter sales of Genzyme reached 525 million, an increase of 25.6%, driven by growth of Cerezyme and Fabrazyme and the launch of Aubagio in the U.S. Genzyme recorded strong performance in the U.S. and Emerging Markets growing 38.5% ( 194 million) and 40.2% ( 110 million), respectively. First-half sales of Genzyme totaled 1,018 million, an increase of 25.5%.

Sales of Cerezyme increased 18.0% to 171 million in the second quarter driven by restored supply and new patient accruals. Emerging Markets sales increased 60.5% to 57 million. Sales of Cerezyme grew 7.0% (to 45 million) and 3.7% (to 56 million) in the U.S. and in Western Europe, respectively. First-half sales of Cerezyme reached 342 million, up 17.4%.

In the second quarter, Fabrazyme continued to deliver strong performance with sales of 91 million, up 28.4% driven by Western Europe (sales grew 90.9% to 21 million) where the product continued to gain market share from the competitive product. In the U.S., sales of Fabrazyme reached 50 million, an increase of 30.8% resulting from new patient accruals. First-half sales of Fabrazyme were 183 million, up 56.2%.

(10) Source: Insight Health, Weekly Data in Units, MS within GLP-1 market.

Second-quarter sales of Myozyme /Lumizyme grew 15.0% to 126 million, driven by Emerging Markets (up 50.0% to 20 million), Western Europe (up 9.5% to 69 million) and the U.S. (up 10.7% to 30 million). First-half sales of Myozyme /Lumizyme were 242 million, up 9.8%.

Sales of Aubagio , were 33 million and 53 million in the second quarter and first half, respectively. The product was approved in the U.S. in September 2012 as a new once-daily, oral treatment indicated for patients with relapsing forms of multiple sclerosis. In March, the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA issued a positive opinion recommending the approval of Aubagio for the treatment of adult patients with relapsing remitting MS. In June, the CHMP issued a positive opinion on new active substance designation for Aubagio which is expected to provide 10 years of exclusivity.

In June, the CHMP also issued a positive opinion for the approval of Lemtrada (alemtuzumab, being developed in multiple sclerosis in collaboration with Bayer HealthCare) for the treatment of adult patients with relapsing remitting multiple sclerosis (RRMS) with active disease defined by clinical or imaging features. The European Commission is expected to render a final decision to grant marketing authorizations for Lemtrada and Aubagio in the EU in the coming months.

Other Innovative Products(11)

(11) Includes new product launches which do not belong to the other Growth Platforms

Second-quarter and first-half sales of Multaq were 69 million (up 10.9%) and 131 million (up 4.7%), respectively. Jevtana sales were 54 million in the second quarter, reflecting lower sales in the U.S. due to a more competitive environment. In Western Europe sales of the product were stable at 25 million. First-half sales of Jevtana were 106 million (down 10.1%). Second-quarter and first-half sales of Mozobil reached 25 million (up 13.0%) and 51 million (up 15.6%), respectively. Zaltrap (aflibercept, collaboration with Regeneron) generated sales of 14 million in the second quarter and 25 million in the first half. In the U.S., where the product was launched at the end of August 2012, sales were 10 million in the second quarter. In February 2013, the European Commission granted marketing authorization in Europe for Zaltrap . The first launches of Zaltrap in the European Union started with Germany and the UK at the end of the first quarter. Launches in other EU countries will continue over the course of the year.

At the end of January 2013, Sanofi launched Auvi-Q (12) (epinephrine injection) in the U.S. Auvi-Q is the first-and-only epinephrine auto-injector with audio and visual cues for the emergency treatment of life-threatening allergic reactions in people who are at risk or have a history of anaphylaxis. Sales of Auvi-Q were 9 million in the second quarter and 15 million in the first half.

Established Pharmaceutical Products

(12) Sanofi U.S. licensed the North America commercialization rights to Auvi-Q from Intelliject.Inc.

Sales of Plavix were 493 million, down 1.3% in the second-quarter impacted by decreased sales of active ingredient for the U.S. ( 5 million versus 28 million in the second quarter of 2012) as the product lost its exclusivity in the U.S. on May 17, 2012. In Japan, sales of Plavix reached 189 million, an increase of 7.8%. In Emerging Markets, sales grew 10.9% to 219 million driven by China ( 113 million) which increased 16.4%, despite a 9.9% price cut in October 2012, and solid performance in the Middle East. In Western Europe, sales of Plavix were 69 million, a decrease of 22.5%, impacted by generic competition. First-half sales of Plavix totaled 943 million, down 3.0%.

Sales of Lovenox were 436 million in the second quarter, a decrease of 9.2%, mainly due to generic competition in the U.S. where sales of the branded product declined 43.7% to 48 million. Sales of the product were 148 million (down 2.5%) in Emerging Markets and 215 million (down 1.4%) in Western Europe. First-half sales of Lovenox were 864 million, a decrease of 13.6%.

Second-quarter sales of Aprovel /Avapro decreased 27.5% to 238 million, reflecting generic competition in Western Europe where sales decreased 45.3% to 94 million. In France, sales of the product decreased 66.8% due to generic competition on both formulations (monotherapy and combination with a diuretic). In Emerging Markets, sales of Aprovel /Avapro grew 2.8% to 108 million. First-half sales of Aprovel /Avapro totaled 479 million, down 24.3%.

Renvela /Renagel generated sales of 175 million in the second quarter, an increase of 7.9% driven by Emerging Markets (sales were 19 million, up 42.9%), Western Europe (sales were up 9.1% to 36 million) and the U.S. (sales were 115 million, up 6.3%). First-half sales of Renvela /Renagel totaled 346 million, an increase of 12.5%.

Second-quarter sales of Taxotere decreased 22.0% to 114 million, impacted by generic competition in Emerging Markets ( 54 million, down 24.7%), in the U.S. ( 19 million, down 13.6%) and Western Europe ( 6 million, down 53.8%). First-half sales of Taxotere reached 222 million, a decrease of 23.0%.

Synvisc /Synvisc-One sales were stable at 105 million in the second quarter. First-half sales of the product were 182 million (up 0.5%).

Sales of the Ambien family of products totaled 92 million, a decrease of 17.8% in the second quarter due to generic competition in Japan where sales decreased 26.0% to 46 million. First-half sales of the Ambien family of products were 193 million, down 15.0%.

Sales of Allegra as a prescription drug were 79 million, down 25.4% in the second quarter. In Japan, sales of Allegra as a prescription drug were down 35.2% to 46 million reflecting the entry of generics on the market since February and an earlier peak of the pollen season as compared to last year. First-half sales of Allegra were 248 million, down 6.8%.

Second-quarter sales of Eloxatin were 60 million, a decrease of 83.7%, reflecting generic competition in the U.S. where the product lost its market exclusivity August 9, 2012 and in Emerging Markets ( 31 million, down 20.0%). First-half sales of Eloxatin reached 119 million (down 84.2%). Eloxatin was recently approved in China for the treatment of hepatocellular carcinoma.

Consumer Healthcare products (CHC) recorded second-quarter sales of 729 million, an increase of 1.8%. Essentiale and Enterogermina recorded double-digit growth in sales. Sales of Allegra OTC increased 8.2% to 65 million, which includes the recent launch in Japan. Sales in Emerging Markets increased 2.8% to 352 million despite lower sales in China and Mexico. A favorable sequential trend in China was observed in the second quarter following changes implemented in distribution network and reduced inventory levels in the first quarter.

First-half sales of CHC reached 1,540 million, an increase of 2.5%. In the U.S., Chattem will re-launch Rolaids in the third quarter of 2013.

Sales of Generics were 300 million in second-quarter, down 36.8%, driven by reduced sales in Brazil, affected by underperformance and an adjustment of 122 million, leading to a negative variation of 212 million. Excluding Brazil, sales of generics increased 10.2% in the second quarter. In the U.S., Generics sales were down 19.4% to 53 million reflecting lower sales of the authorized generic of Aprovel . In Western Europe, sales of generics grew 22.0% reflecting strong performance in France following local measures taken by the French government to further develop the Generics segment. First-half sales of Generics reached 723 million, a decrease of 19.8% or an increase of 8.2% excluding Brazil.

First-half consolidated sales of Sanofi Pasteur were 1,457 million, an increase of 7.2%. Second-quarter consolidated sales of Sanofi Pasteur reached 760 million, up 0.4% reflecting strong performance of Pentaxim in Emerging Markets partially offset by the unfavorable impact of phasing for seasonal influenza vaccine in the Southern Hemisphere in the second quarter of 2012 and supply limitations for Pentacel in the U.S.

Sales of Polio/Pertussis/Hib vaccines increased 12.5% to 293 million, driven by the performance of Pentaxim which largely offset supply limitations for Pentacel in the U.S. Total sales of Pentaxim grew 48.3% to 87 million driven by good performances in Mexico and China. Sales of Imovax in Japan were 5 million reflecting the end of the catch-up cohort following the launch in September 2012. In the U.S., as previously announced, Sanofi Pasteur foresees progressive supply recovery of Pentacel to begin in the third quarter of 2013. First-half sales of Polio/Pertussis/Hib vaccines grew 14.1% to 563 million.

Second-quarter sales of influenza vaccines were 53 million, a decrease of 32.5% due to the high level of sales in the second quarter of 2012 which benefited from favorable phasing for seasonal influenza vaccines in the Southern Hemisphere. First-half sales of influenza vaccines were 172 million, up 3.0%. In June, the FDA approved the supplemental biologics license application for licensure of Sanofi Pasteur four-strain influenza vaccine, Fluzone Quadrivalent vaccine. This vaccine is the newest addition to the Fluzone family of influenza vaccines. The 2013 influenza season will be the first in which quadrivalent influenza vaccines will be available in the U.S. In July, shipments of the first lots of Fluzone vaccines to U.S. health care providers began.

Second-quarter sales of Menactra reached 100 million (down 6.3%), reflecting phasing of public orders in the U.S. (sales were 77 million, a decrease of 18.4%) partially offset by good performance in the Middle East and to a lesser extent Latin America. First-half sales of Menactra were 167 million, an increase of 2.4%.

Adult booster vaccines sales were 124 million (down 13.7%) and 209 million (down 9.0%) in the second quarter and the first half, respectively due to lower sales of Adacel .

Sales of travel and other endemic vaccines reached 98 million (up 1.0%) in the second quarter and 172 million (down 0.6%) in the first half, respectively, and were impacted by the temporary production suspension of Theracys /Immucyst and BCG vaccines.

Second-quarter sales of other vaccines were 69 million, an increase of 30.9%, reflecting growth of VaxServe(13).

(13) A Sanofi Pasteur company, US supplier of vaccines.

Sanofi Pasteur MSD (not consolidated), the joint venture with Merck & Co. in Europe, reported sales of 160 million, a decrease of 8.9% (on a reported basis). First-half sales of Sanofi Pasteur MSD were stable (on a reported basis) at 334 million.

Second-quarter sales of Animal Health were 529 million, down 5.7%. Sales in Emerging Markets were 154 million, an increase of 11.2%, driven by vaccines. First-half sales of Animal Health totaled 1,083 million, down 4.4%.

Second-quarter sales of the Companion Animals segment were 323 million, a decrease of 14.0% reflecting lower sales of the anti-parasiticide Frontline /fipronil family of products (down 24.0% to 165 million). Sales of this family of products were impacted by a weak season for fleas and ticks given unfavorable weather conditions, increased competition from prescription-only products in veterinary channels and high promotional spend from fipronil branded generics. In Emerging Markets, sales of the Frontline /fipronil family of products reached 22 million, an increase of 9.5%.

Second-quarter sales of the Production Animals segment grew 11.1% to 206 million driven by the Avian, Ruminant and Veterinary Public Health segments especially due to the performance in Emerging Markets.

The acquisition of the animal health division of the Indian company Dosch Pharmaceuticals Private Limited was finalized in the second quarter of 2013. This acquisition creates a market entry for Merial in India s strategically important and growing animal health sector.

Net sales by geographic region

(a) World less the U.S., Canada, Western Europe, Japan, Australia and New Zealand

(b) France, Germany, UK, Italy, Spain, Greece, Cyprus, Malta, Belgium, Luxembourg, Portugal, Netherlands, Austria, Switzerland, Sweden, Ireland, Finland, Norway, Iceland, Denmark

(c) Japan, Canada, Australia and New Zealand

Second-quarter sales in Emerging Markets totaled 2,669 million, a decrease of 2.3% including a negative variation of generics sales in Brazil ( 212 million). Excluding Brazil generics, sales grew 5.3% in the second quarter. Double-digit growth was recorded for Diabetes (up 17.7%), Vaccines (up 10.1%), Genzyme (up 40.2%) and Animal Health (up 11.2%). Despite recent price cuts, sales in China grew 15.3% to 372 million driven by

Plavix , Aprovel , Lantus , Vaccines and Animal Health. Sales in Eastern Europe/Russia and Turkey increased 1.3%, which included good performance of Russia (up 16.3% to 228 million). In Brazil, sales were 154 million reflecting a net sales adjustment of 122m, as well as lower oncology and flu vaccines sales.

Genfar S.A., a leading pharmaceuticals manufacturer headquartered in Bogota, Colombia, was consolidated in the second quarter. With this acquisition, Sanofi has become a market leader in Colombia and has further expanded its portfolio of affordable pharmaceuticals in Latin America.

Second-quarter sales in the U.S. were 2,463 million, down 10.0% reflecting primarily the loss of exclusivity of Eloxatin at the beginning of August 2012 (down 97.4%) which was partially offset by the strong performance of Diabetes (up 21.0%) and Genzyme (up 38.5%). First-half sales in the U.S. totaled 4,797 million, down 9.9%.

Sales in Western Europe were 1,958 million in the second quarter, a decrease of 7.9%, impacted by generic competition to Aprovel as well as austerity measures. First-half sales in Western Europe totaled 3,958 million, down 9.0 %.

Sales in Japan totaled 594 million, a decrease of 7.2%, primarily reflecting the impact of generic competition to Allegra , Myslee and Amaryl partially offset by the performance of vaccines and Plavix . First-half sales in Japan were 1,284 million, up 1.0%.

Consult Appendix 7 for full overview of Sanofi s R&D pipeline

Since the publication of the first-quarter 2013 results on May 2, 2013, the regulatory newsflow has been favorable:

In June The Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA) issued a positive opinion for approval of Lemtrada (alemtuzumab) for the treatment of adult patients with relapsing remitting multiple sclerosis (RRMS) with active disease defined by clinical or imaging features. In addition, the CHMP issued a positive opinion on the new active substance designation for Aubagio (teriflunomide). In March, the CHMP issued a positive opinion recommending the approval of Aubagio for the treatment of adult patients with relapsing remitting MS.

In June, the Japan s Ministry of Health, Labour and Welfare approved the manufacturing and distribution of Lyxumia for the treatment of type 2 diabetes. Lyxumia , the first once-daily prandial GLP-1 receptor agonist (RA), is also the first GLP-1 RA approved in Japan for use in combination with basal insulin. Lyxumia is indicated for patients with type 2 diabetes when the following do not provide adequate glycemic control: diet and exercise and sulfonylureas or diet and exercise and soluble prolonged-acting or intermediate-acting insulin.

In June, the U.S. Food and Drug Administration approved the supplemental biologics license application for licensure of Sanofi Pasteur s four-strain influenza vaccine, Fluzone Quadrivalent vaccine. Fluzone Quadrivalent vaccine is the newest addition to the Fluzone family of influenza vaccines. Like Sanofi Pasteur s Fluzone vaccine, Fluzone Quadrivalent vaccine is licensed for use in children six months of age and older, adolescents, and adults. The 2013 influenza season will be the first in which quadrivalent influenza vaccines will be available in the U.S.