Sanofi (SNY) 6-K FDA approves Praluent® (alirocumab) to prevent heart attack, stroke and unstable angina requiring hospitalization

Exhibit 99.1

Press Release Source: Sanofi (EURONEXT: SAN) (NASDAQ: SNY)

FDA approves Praluent^® (alirocumab) to prevent heart attack, stroke and unstable angina requiring hospitalization

• Praluent is the first PCSK9 inhibitor that has shown a meaningful reduction in death from any cause

• Praluent treatment effect was observed in patients already receiving other lipid-lowering therapies, including maximally-tolerated statins

PARIS and TARRYTOWN, NY – April 26, 2019 – The U.S. Food and Drug Administration (FDA) has approved Praluent^®(alirocumab) to reduce the risk of heart attack, stroke, and unstable angina requiring hospitalization in adults with established cardiovascular (CV) disease.

“Today’s FDA approval marks a significant achievement in the treatment of adults with established cardiovascular disease, who are among those at greatest risk of death or disability caused by serious cardiovascular events,”said John Reed, M.D., Ph.D., Global Head of Research & Development, Sanofi. “Praluent has already helped many adults lower theirLDL-C levels, and this new indication provides an opportunity to help appropriate patients by reducing the risk of serious, life-threatening cardiovascular events, including heart attacks and stroke.”

High levels of “bad” cholesterol, also known aslow-density lipoprotein cholesterol(LDL-C), increase patients’ risk for serious CV events such as heart attack or stroke. Adults who experience a heart attack or stroke have an approximately one in three chance to have another CV event.

“Heart disease accounts for one quarter of all American deaths each year and many others are at risk for heart attack and stroke due to uncontrolledLDL-C levels,”said George D. Yancopoulos, M.D., Ph.D., President and Chief Scientific Officer, Regeneron. “The Phase 3 ODYSSEY OUTCOMES trial showed that people who received Praluent significantly reduced their risk for serious cardiovascular events. There was also a clinically-meaningful reduction in death from any cause with Praluent treatment. With this approval, and the recent introduction of a lower U.S. Praluent list price, we hope that more patients in need will be able to access Praluent.”

The FDA approval is based on data from ODYSSEY OUTCOMES, which was published in theNew England Journal of Medicine in November 2018, assessing the effect of adding Praluent to maximally-tolerated statins on CV outcomes in 18,924 patients who had an acute coronary syndrome (ACS) within a year of enrolling in the trial. Patients who received Praluent in the trial experienced:

• A 15% reduced risk for major CV events. The primary endpoint included time to first heart attack, stroke, death from coronary heart disease (CHD), or unstable angina requiring hospitalization (HR 0.85; 95% CI, 0.78 to 0.93; p=0.0003).

• A 27% reduced risk of stroke, 14% reduced risk ofnon-fatal heart attack and 39% reduced risk of unstable angina requiring hospitalization.*

• A 15% reduced risk of death from any cause (also calledall-cause mortality; HR 0.85; 95% CI, 0.73 to 0.98; nominal p=0.026) was also observed.*

* Because statistical testing of these endpoints was performed outside of the hierarchy, the results are not considered statistically significant.

Adverse events were similar between the Praluent and placebo groups, except for injection site reactions (Praluent 3.8%, placebo 2.1%). In ODYSSEY OUTCOMES, the adverse events that occurred in>5% of patients included:non-cardiac chest pain (7.0% Praluent, 6.8% placebo), nasopharyngitis (6.0% Praluent, 5.6% placebo) and myalgia (5.6% Praluent, 5.3% placebo).

Expanded Indication to Include Patients with Other Types of HighLDL-C

The FDA also approved Praluent as an adjunct to diet, alone or in combination with other lipid-lowering therapies (e.g., statins, ezetimibe), for the treatment of adults with primary hyperlipidemia (including heterozygous familial hypercholesterolemia) to reduceLDL-C.

Praluent was the first PCSK9 (proprotein convertase subtilisin/kexin type 9) inhibitor approved by the FDA and is the only PCSK9 inhibitor available in two doses with two levels of efficacy as a single 1 mL injection (75 mg and 150 mg) once every two weeks. It can also be administered as 300 mg once every four weeks (monthly), enabling physicians to tailor treatment based on an individual patient’sLDL-C-lowering needs.    

About ODYSSEY OUTCOMES

ODYSSEY OUTCOMES, the longest CV outcomes trial of any PCSK9 inhibitor to date, assessed the effect of Praluent on the occurrence of major adverse CV events in patients who had experienced an ACS before enrolling in the trial, and who were already on intensive or maximally-tolerated statin treatment. Patients were randomized to receive Praluent (n=9,462) or a placebo (n=9,462) and were assessed for a median of 2.8 years, with some patients being treated for up to five years. Approximately 90% of patients were on high-intensity statins prior to randomization.

The trial was designed to maintain patients’LDL-C levels between25-50 mg/dL(0.65-1.29 mmol/L), using two different doses of Praluent (75 mg and 150 mg). Praluent-treated patients started the trial on 75 mg every two weeks and switched to 150 mg every two weeks if theirLDL-C levels remained above 50 mg/dL (n=2,615). Some patients who switched to 150 mg switched back to 75 mg if theirLDL-C fell below 25 mg/dL (n=805), and patients who experienced two consecutiveLDL-C measurements below 15 mg/dL (0.39 mmol/L) while on the 75 mg dose (n=730) stopped active Praluent therapy for the remainder of the trial.

About Praluent

Praluent^® (alirocumab) inhibits the binding of PCSK9 to the LDL receptor and thereby increases the number of available LDL receptors on the surface of liver cells to clear LDL, which lowersLDL-C levels in the blood. Praluent was developed by Regeneron and Sanofi under a global collaboration agreement.

Praluent is approved in more than 60 countries worldwide, including the U.S., European Union (EU), Japan, Canada, Switzerland, Mexico and Brazil. In the U.S., Praluent is approved to reduce the risk of heart attack, stroke, and unstable angina requiring hospitalization in adults with established CV disease. Praluent is also approved as an adjunct to diet, alone or in combination with other lipid lowering therapies (e.g., statins, ezetimibe), for the treatment of adults with primary hyperlipidemia (including heterozygous familial hypercholesterolemia) to reduceLDL-C.

About Regeneron Pharmaceuticals, Inc.

Regeneron (NASDAQ: REGN) is a leading biotechnology company that invents life-transforming medicines for people with serious diseases. Founded and led for 30 years by physician-scientists, our unique ability to repeatedly and consistently translate science into medicine has led toseven FDA-approved treatments and numerous product candidates in development, all of which were homegrown in our laboratories. Our medicines and pipeline are designed to help patients with eye diseases, allergic and inflammatory diseases, cancer, cardiovascular and metabolic diseases, neuromuscular diseases, infectious diseases and rare diseases.

Regeneron is accelerating and improving the traditional drug development process through our proprietaryVelociSuite^® technologies, such asVelocImmune^® which produces optimized fully-human antibodies, and ambitious research initiatives such as the Regeneron Genetics Center, which is conducting one of the largest genetics sequencing efforts in the world.

For additional information about the company, please visitwww.regeneron.com or follow @Regeneron on Twitter.

About Sanofi

Sanofi is dedicated to supporting people through their health challenges. We are a global biopharmaceutical company focused on human health. We prevent illness with vaccines, provide innovative treatments to fight pain and ease suffering. We stand by the few who suffer from rare diseases and the millions with long-term chronic conditions.

With more than 100,000 people in 100 countries, Sanofi is transforming scientific innovation into healthcare solutions around the globe.

Sanofi, Empowering Life

Sanofi Media Relations Contact
Nicolas Kressmann Tel: +1 (732)532-5318 nicolas.kressmann@sanofi.com   Regeneron Media Relations Contact Joe Ricculli Tel: +1 (914)847-0405 joseph.ricculli@regeneron.com Sanofi Investor Relations Contact
George Grofik
Tel: +33 (0)1 53 77 45 45 ir@sanofi.com   Regeneron Investor Relations Contact Mark Hudson Tel: +1 (914)847-3482 mark.hudson@regeneron.com

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