Sanofi (SNY) 6-K Sanofi to present growth opportunities and development strategy for Dupixent® (dupilumab) in type 2 inflammatory diseases

Exhibit 99.1

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

Sanofi to present growth opportunities and development strategy for Dupixent^® (dupilumab) in type 2 inflammatory diseases

• Additional data contribute to the growing body of evidence demonstrating Dupixent’s best in class safety profile combined with strong efficacy benefit for atopic dermatitis and further validate it as a standard of care treatment for asthma

• Dupixent’s unique mechanism of action simultaneously inhibitsIL-4 andIL-13, which play a key role in type 2 inflammation in multiple diseases

• Recent evidence further supports additional clinical uses in diseases driven by type 2 inflammation including Eosinophilic Esophagitis and a subset of Chronic Obstructive Pulmonary Disease

PARIS – June 11, 2020– Sanofi commercial and R&D executives will provide an overview of the growth and development strategy for Dupixent^®(dupilumab) in the third of its five-part series to highlight Sanofi’s progress in R&D. As announced in December 2019, Sanofi expects to deliver strong growth for Dupixent with the ambition of achieving more than €10 billion in peak sales driven by its selective mechanism of action targeting the type 2 inflammation pathway. Sanofico-develops andco-commercializes Dupixent with Regeneron.

“By specifically targetingIL-4 andIL-13, Dupixent’s mechanism of action is uniquely suited to help address conditions driven by type 2 inflammation,” said John Reed, M.D., Ph.D., Global Head of Research and Development, Sanofi. “While atopic dermatitis and asthma are the foundational diseases where Dupixent was first approved for use, great opportunity exists across multiple diseases where type 2 inflammation plays a role. We are therefore aggressively pursuing clinical evaluation of additional indications where patients are urgently awaiting solutions for their unmet medical needs.”

Today’s presentation will detail five potential future line extensions for Dupixent, including:

• Eosinophilic Esophagitis (EoE)– It was recentlyannounced that Part A of the Dupixent EoE pivotal Phase 3 trial met bothco-primary endpoints as well as all key secondary endpoints. Dupixent demonstrated significant clinical and anatomic improvements, including the ability to swallow. In the U.S., approximately 160,000 patients with EoE are currently treated, of which an estimated 50,000 have failed multiple treatments.

Part B of the Phase 3 trial is ongoing, and, if the results are positive, regulatory submissions are expected to be filed by the end of 2022. The U.S. Food and Drug Administration (FDA) has granted orphan drug designation to Dupixent for the treatment of EoE. Currently, noFDA-approved treatments are available for this condition.

• Chronic Obstructive Pulmonary Disease (COPD) with Evidence of Type 2 Inflammation– Dupixent may benefit COPD patients with evidence of type 2 inflammation. Currently, a Phase 3 study is underway in COPD, with approximately 900 patients enrolled. A second confirmatory study is now being initiated based on a rigorously defined, prespecified futility analysis of data from the ongoing COPD trial. If successful, regulatory submissions would be made in the 2024 timeframe. In the U.S., approximately 300,000 patients with COPD continue to suffer exacerbations despite available treatment options.

• Prurigo Nodularis (PN)– PN is a skin disease resulting in intense itching (pruritus) that adversely impacts quality of life, with many patients developing anxiety and depression. Currently, no approved treatments are available for PN, which represents a significant unmet need with approximately 74,000 patients eligible for a biologic in the U.S.

Currently, two Phase 3 studies are underway testing Dupixent, each enrolling 150 patients with PN. Topline trial results are expected in 2021, which could support regulatory filings at the end of 2021.

• Chronic Spontaneous Urticaria (CSU) –CSU is a common condition characterized by the recurrent appearance of highly pruritic (itchy) wheals (hives) with or without angioedema. CSU patients experience debilitating hives and pruritus secondary to mast cell and basophil dysregulation. Approximately,40-50% of patients do not respond to approved treatments including antihistamines and other biologic treatments. Approximately 300,000 patients are eligible for a biologic in the U.S.

Earlier this year, a 240 patient registrational study of Dupixent in CSU was initiated, and if the results are positive, regulatory filings would be submitted in 2022.

• Bullous Pemphigoid (BP) – BP is a rare autoimmune skin disease with type 2 inflammatory features, including pruritic plaques and large fluid-filled blisters. Approximately 27,000 patients are chronically treated with oral corticoid steroids who are potentially eligible for a biologic in the U.S.

A pivotal Phase 3 trial testing Dupixent in BP patients has been initiated. If the results are positive, regulatory filings will be submitted in 2023+. The FDA has granted orphan drug designation to Dupixent for the treatment of BP.

All of these potential uses are investigational, and the safety and efficacy of Dupixent in any of these indications has not been evaluated by any regulatory authority.

The virtual investor event will be held today from3:00-4:30 pm CET /9:00-10:30 am EDT. Sanofi speakers include:

• Brian Foard, Global Head, Dupixent Franchise

• Frank Nestle, Global Head of Research, Immunology & Inflammation

• Naimish Patel, Global Head of Development, Immunology & Inflammation

• John Reed, Global Head of Research and Development

Joining for Q&A will be Sanofi Chief Executive Officer Paul Hudson, Jean-Baptiste de Chatillon, Sanofi Chief Financial Officer, and Bill Sibold, Global Head of Specialty Care.

Additional information about today’s Dupixent presentation can be found at:https://www.sanofi.com/en/investors/financial-results-and-events/investor-presentations/2020-dupixent-presentation

About Dupixent

Dupixent is approved in the U.S. to treat patients aged 6 years and older withmoderate-to-severe atopic dermatitis that is not well controlled with prescription therapies used on the skin (topical), or who cannot use topical therapies; for use with other asthma medicines for the maintenance treatment ofmoderate-to-severe eosinophilic or oral steroid dependent asthma in patients aged 12 years and older whose asthma is not controlled with their current asthma medicines; and for use with other medicines for the maintenance treatment of CRSwNP in adults whose disease is not controlled. In adolescents 12 years of age or older, it is recommended that Dupixent be administered by or under the supervision of an adult. In children younger than 12 years of age, Dupixent should be administered by a caregiver.

Outside of the U.S., Dupixent is approved for specific patients withmoderate-to-severe atopic dermatitis and certain patients with asthma in a number of other countries around the world, including the EU and Japan. Dupixent is also approved in the EU and Japan to treat certain adults with severe CRSwNP. The 200 mg and 300 mgpre-filled pens are currently approved in the EU.

Dupilumab Development Program

In addition to the currently approved indications, Sanofi and Regeneron are also studying dupilumab in a broad range of clinical development programs for diseases driven by allergic and other type 2 inflammatory disorders, including pediatric asthma (6

to 11 years of age, Phase 3), pediatric atopic dermatitis (6 months to 5 years of age, Phase 2/3), chronic obstructive pulmonary disease (Phase 3), bullous pemphigoid (Phase 3), prurigo nodularis (Phase 3), chronic spontaneous urticaria (Phase 3), and food and environmental allergies (Phase 2). These potential uses are investigational, and the safety and efficacy have not been evaluated by any regulatory authority. Dupilumab is being jointly developed by Sanofi and Regeneron under a global collaboration agreement.

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

Media Relations Contact Ashleigh Koss Tel.: +1 908 205 2572 Ashleigh.Koss@sanofi.com	Investor Relations Contact Felix Lauscher Tel.: +33 (0)1 53 77 45 45 ir@sanofi.com
Quentin Vivant Tél.: +33 (0)1 53 77 46 46 mr@sanofi.com

Sanofi Forward-Looking Statements

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