6-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16

UNDER THE SECURITIES EXCHANGE ACT OF 1934

For the month of March 2021

Commission File Number: 001-31368

SANOFI

(Translation of registrant’s name into English)

54, rue La Boétie, 75008 Paris, FRANCE

(Address of principal executive offices)

Indicate by check mark whether the registrant files or will file annual reports under cover Form 20-F or Form 40-F.

Form 20-F  ☒                Form 40-F  ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1): _____

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7): _____

Indicate by check mark whether the registrant by furnishing the information contained in this Form is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.

Yes  ☐                                         No  ☒

If “Yes” marked, indicate below the file number assigned to the registrant in connection with Rule 12g3-2(b): 82-________

In March 2021, Sanofi issued the press releases attached hereto as Exhibits 99.1 and 99.2 which are incorporated herein by reference.

Exhibit List

Exhibit No.	Description
Exhibit 99.1	Press release dated March 15, 2021: Phase 3 trial of Libtayo® (cemiplimab) monotherapy in advanced cervical cancer stopped early for positive result on overall survival
Exhibit 99.2	Press release dated March 12, 2021: Sanofi and Translate Bio initiate Phase 1-2 clinical trial of mRNA COVID-19 vaccine candidate

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Exhibit Index

Exhibit No.	Description
Exhibit 99.1	Press release dated March  15, 2021: Phase 3 trial of Libtayo® (cemiplimab) monotherapy in advanced cervical cancer stopped early for positive result on overall survival
Exhibit 99.2	Press release dated March 12, 2021: Sanofi and Translate Bio initiate Phase 1-2 clinical trial of mRNA COVID-19 vaccine candidate

3

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Dated: March 19, 2021	SANOFI
	By	/s/  Alexandra Roger
		Name:	Alexandra Roger
		Title:	Head of Securities Law and Capital Markets

4

EX-99.1

Exhibit 99.1

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

Phase 3 trial of Libtayo^® (cemiplimab) monotherapy in advanced cervical cancer stopped early for positive result on overall survival

* Libtayo is the first immunotherapy to demonstrate improved overall survival in patients with cervical cancer, reducing the risk of death by 31% compared to chemotherapy

* Trial enrolled patients with advanced cervical cancer regardless of PD-L1 status

* Fourth cancer type where Libtayo has positive pivotal data; regulatory submissions planned in 2021

PARIS and TARRYTOWN, N.Y. – March 15, 2021 – Positive results demonstrating an overall survival (OS) benefit from the Phase 3 trial investigating Sanofi and Regeneron’s PD-1 inhibitor Libtayo^® (cemiplimab) monotherapy compared to chemotherapy in patients previously treated with chemotherapy whose cervical cancer is recurrent or metastatic, were announced today. The trial will be stopped early based on a unanimous recommendation by the Independent Data Monitoring Committee (IDMC), and the data will form the basis of regulatory submissions in 2021.

“Libtayo monotherapy is the first medicine to demonstrate an improvement in overall survival in women with recurrent or metastatic cervical cancer following progression on platinum-based chemotherapy in a Phase 3 trial,” said Krishnansu S. Tewari, M.D., Professor and Director of the Division of Gynecologic Oncology at the University of California, Irvine and a trial investigator. “This landmark clinical achievement will bring hope to women with advanced cervical cancer who are often younger than patients with other cancers. This is reflected in the trial where the average age was 51.”

This is the largest Phase 3 randomized clinical trial in advanced cervical cancer and included women (median age: 51 years) with either squamous cell carcinoma or adenocarcinoma. Patients were randomized to receive Libtayo monotherapy (350 mg every three weeks) or an investigator’s choice of commonly used chemotherapy (pemetrexed, vinorelbine, topotecan, irinotecan or gemcitabine). Compared to chemotherapy, patients receiving Libtayo experienced:

• Total population: 31% reduced risk of death

o Median 12.0 months survival for Libtayo (n=304) compared to 8.5 months for chemotherapy (n=304); hazard ratio (HR): 0.69; 95% confidence interval (CI): 0.56-0.84 (p<0.001)

• Squamous cell carcinoma: 27% reduced risk of death

o Median 11.1 months survival for Libtayo (n=239) compared to 8.8 months for chemotherapy (n=238); HR: 0.73; 95% CI: 0.58-0.91 (p=0.003)

• Adenocarcinoma: 44% reduced risk of death

o Median 13.3 months survival for Libtayo (n=65) compared to 7.0 months for chemotherapy (n=66); HR: 0.56; 95% CI: 0.36-0.85 (p<0.005; not adjusted for multiplicity)

The primary endpoint for the trial was OS, analyzed first among patients with squamous cell carcinoma, then in the total population. Per a protocol-specified interim analysis, the IDMC reviewed OS data when approximately 85% of events had occurred among patients with squamous cell carcinoma. Based on the highly significant effect on OS among these patients, the IDMC recommended stopping the trial. Detailed results will be presented at an upcoming medical meeting. The use of Libtayo in cervical cancer is investigational and has not been fully reviewed by any regulatory authority.

No new Libtayo safety signals were observed. Safety was assessed in patients who received at least one dose of study treatment: 300 patients in the Libtayo group (median duration of exposure: 15 weeks; range: 1-101 weeks) and 290 patients in the chemotherapy group (median duration of exposure: 10 weeks; range: 1-82 weeks). Adverse events (AEs) were observed in 88% of Libtayo patients and 91% of chemotherapy patients, with serious AEs occurring in 30% of Libtayo patients and 27% of chemotherapy patients. The five most common AEs were anemia (25% Libtayo, 45% chemotherapy), nausea (18% Libtayo, 33% chemotherapy), fatigue (17% Libtayo, 16% chemotherapy), vomiting (16% Libtayo, 23% chemotherapy) and constipation (15% Libtayo, 20% chemotherapy). Other AEs that occurred more often in the Libtayo group and in at least 10% of patients were fatigue (17% Libtayo, 16% chemotherapy), urinary tract infections (12% Libtayo, 9% chemotherapy), back pain (11% Libtayo, 9% chemotherapy) and arthralgia (10% Libtayo, 3% chemotherapy). Discontinuations due to AEs occurred in 8% of Libtayo patients and 5% of chemotherapy patients.

“We are committed to developing therapies for cancers with high unmet needs including patients with advanced cervical cancer,” said Peter C. Adamson, M.D., Global Development Head, Oncology and Pediatric Innovation at Sanofi. “Combined with data from our non-melanoma skin cancer and lung cancer studies, these data contribute to the growing evidence demonstrating the significant potential of Libtayo to treat a spectrum of difficult-to-treat cancers.”

Today’s announcement follows the recent U.S. approval of Libtayo monotherapy for certain patients with advanced non-small cell lung cancer (NSCLC) whose tumors have high PD-L1 expression. The FDA also recently authorized the use of Libtayo as the first immunotherapy indicated for patients with basal cell carcinoma (BCC) previously treated with a hedgehog pathway inhibitor (HHI) or for whom an HHI is not appropriate, whose cancer is either locally advanced (full approval) or metastatic (accelerated approval). In 2018, Libtayo was approved as the first systemic treatment for certain patients with advanced cutaneous squamous cell carcinoma (CSCC).

“Recurrent or metastatic cervical cancer is notoriously difficult to treat and has no approved standard of care after first-line chemotherapy,” said Israel Lowy, M.D., Ph.D., Senior Vice President, Translational and Clinical Sciences, Oncology, at Regeneron. “This trial, which enrolled patients regardless of their PD-L1 status, demonstrated that Libtayo helped patients with recurrent or metastatic cervical cancer live longer after progression on prior chemotherapy. This is the fourth patient population in which Libtayo has shown clinical benefit and we look forward to submitting the results to regulatory authorities later this year.”

About the Phase 3 Trial

This open-label, randomized, multi-center, Phase 3 trial investigated Libtayo monotherapy versus an investigator’s choice of chemotherapy in patients with recurrent or metastatic cervical cancer that has progressed on platinum-based chemotherapy. Patients were allowed to enroll regardless of PD-L1 expression status, and 78% of patients had squamous cell carcinoma and 22% had adenocarcinoma. The trial included women from 14 countries: the U.S., Japan, Taiwan, South Korea, Canada, Russia, Poland, Spain, Brazil, Australia, the UK, Italy, Greece and Belgium.

About Cervical Cancer

Cervical cancer is the fourth leading cause of cancer death in women worldwide and is most frequently diagnosed in women between the ages of 35 and 44. Almost all cases are caused by human papillomavirus (HPV) infection, with approximately 80% classified as squamous cell carcinoma (arising from cells lining the bottom of the cervix) and the remainder largely adenocarcinomas (arising from glandular cells in the upper cervix). Cervical cancer is often curable when detected early and effectively managed, but treatment options are more limited in advanced stages.

It is estimated that approximately 570,000 women are diagnosed with cervical cancer worldwide each year. In the U.S. 14,500 new patients are diagnosed annually, and approximately 4,000 women die each year.

About Libtayo

Libtayo is a fully-human monoclonal antibody targeting the immune checkpoint receptor PD-1 on T-cells. By binding to PD-1, Libtayo has been shown to block cancer cells from using the PD-1 pathway to suppress T-cell activation.

In the U.S., Libtayo is approved for certain patients with advanced stages of CSCC, BCC and NSCLC with ³50% PD-L1 expression. Outside of the U.S., Libtayo is approved for certain patients with advanced CSCC in the European Union and six other countries, including Australia, Brazil, the United Kingdom and Canada.

The generic name for Libtayo in its approved U.S. indications is cemiplimab-rwlc, with rwlc as the suffix designated in accordance with Nonproprietary Naming of Biological Products Guidance for Industry issued by the FDA. Outside of the U.S., the generic name for Libtayo in its approved indication is cemiplimab.

About the Libtayo Development Program

The extensive clinical program for Libtayo is focused on difficult-to-treat cancers. The European Medicines Agency is assessing regulatory submissions for Libtayo monotherapy in advanced NSCLC with ³50% PD-L1 expression and locally advanced BCC following treatment with an HHI, with European Commission decisions expected by mid-2021.

Libtayo monotherapy is being investigated in trials in adjuvant CSCC and neoadjuvant CSCC, as well as in trials combining Libtayo with either conventional or novel therapeutic approaches for both solid tumors and blood cancers. These potential uses are investigational, and their safety and efficacy have not been evaluated by any regulatory authority.

Libtayo is being jointly developed by Regeneron and Sanofi under a global collaboration agreement.

About Regeneron

Regeneron (NASDAQ: REGN) is a leading biotechnology company that invents life-transforming medicines for people with serious diseases. Founded and led for over 30 years by physician-scientists, our unique ability to repeatedly and consistently translate science into medicine has led to nine FDA-approved treatments and numerous product candidates in development, almost 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, pain, hematology, infectious diseases and rare diseases.

Regeneron is accelerating and improving the traditional drug development process through our proprietary VelociSuite^® technologies, such as VelocImmune^®, which uses unique genetically humanized mice to produce optimized fully human antibodies and bispecific antibodies, and through 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 visit www.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 Sally Bain Tel.: +1 (781) 264-1091 sally.bain@sanofi.com	Sanofi Investor Relations Contacts Paris Eva Schaefer-Jansen Arnaud Delepine Yvonne Naughton Sanofi Investor Relations Contacts North America Felix Lauscher Fara Berkowitz Suzanne Greco Sanofi IR main line: Tel.: +33 (0)1 53 77 45 45 investor.relations@sanofi.com https://www.sanofi.com/en/investors/contact
Regeneron Media Relations Contact Taylor Ramsey Tel: +1 (914) 409-2381 taylor.ramsey@regeneron.com	Regeneron Investor Relations Contact Vesna Tosic Tel: +1 (914) 847-5443 vesna.tosic@regeneron.com
Sanofi Forward-Looking Statements This press release 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 regarding the marketing and other potential of the product, or regarding potential future revenues from the product. 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, unexpected regulatory actions or delays, or government regulation generally, that could affect the availability or commercial potential of the product, the fact that product may not be commercially successful, the uncertainties inherent in research and development, including future clinical data and analysis of existing clinical data relating to the product, including post marketing, unexpected safety, quality or manufacturing issues, competition in general, risks associated with intellectual property and any related future litigation and the ultimate outcome of such litigation, and volatile economic and market conditions, and the impact that COVID-19 will have on us, our customers, suppliers, vendors, and other business partners, and the financial condition of any one of them, as well as on our employees and on the global economy as a whole. Any material effect of COVID-19 on any of the foregoing could also adversely impact us. This situation is changing rapidly and additional impacts may arise of which we are not currently aware and may exacerbate other previously identified risks. The risks and uncertainties also include the uncertainties 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, 2020. Other than as required by applicable law, Sanofi does not undertake any obligation to update or revise any forward-looking information or statements. Regeneron Forward-Looking Statements This press release includes forward-looking statements that involve risks and uncertainties relating to future events and the future performance of Regeneron Pharmaceuticals, Inc. (“Regeneron” or the “Company”), and actual events or results may differ materially from these forward-looking statements. Words such as “anticipate,” “expect,” “intend,” “plan,” “believe,” “seek,” “estimate,” variations of such words, and similar expressions are intended to identify such forward-looking statements, although not all forward-looking statements contain these identifying words. These statements concern, and these risks and uncertainties include, among others, the impact of SARS-CoV-2 (the virus that has caused the COVID-19 pandemic) on Regeneron’s business and its employees, collaborators, and suppliers and other third parties on which Regeneron relies, Regeneron’s and its collaborators’ ability to continue to conduct research and clinical programs, Regeneron’s ability to manage its supply chain, net product sales of products marketed or otherwise commercialized by Regeneron and/or its collaborators (collectively, “Regeneron’s Products”), and the global economy; the nature, timing, and possible success and therapeutic applications of Regeneron’s Products and product candidates being

developed by Regeneron and/or its collaborators (collectively, “Regeneron’s Product Candidates”) and research and clinical programs now underway or planned, including without limitation Libtayo^® (cemiplimab) in patients previously treated with chemotherapy whose cervical cancer is recurrent or metastatic; uncertainty of market acceptance and commercial success of Regeneron’s Products and Regeneron’s Product Candidates and the impact of studies (whether conducted by Regeneron or others and whether mandated or voluntary), including the studies discussed or referenced in this press release, on the commercial success of Regeneron’s Products (such as Libtayo) and Regeneron’s Product Candidates; the likelihood, timing, and scope of possible regulatory approval and commercial launch of Regeneron’s Product Candidates and new indications for Regeneron’s Products, such as Libtayo for the treatment of cervical cancer, adjuvant and neoadjuvant cutaneous squamous cell carcinoma, and advanced non-small cell lung cancer (as first-line treatment or in combination with chemotherapy) (as well as in combination with either conventional or novel therapeutic approaches for both solid tumors and blood cancers); safety issues resulting from the administration of Regeneron’s Products (such as Libtayo) and Regeneron’s Product Candidates in patients, including serious complications or side effects in connection with the use of Regeneron’s Products and Regeneron’s Product Candidates in clinical trials; determinations by regulatory and administrative governmental authorities which may delay or restrict Regeneron’s ability to continue to develop or commercialize Regeneron’s Products and Regeneron’s Product Candidates; ongoing regulatory obligations and oversight impacting Regeneron’s Products, research and clinical programs, and business, including those relating to patient privacy; the availability and extent of reimbursement of Regeneron’s Products from third-party payers, including private payer healthcare and insurance programs, health maintenance organizations, pharmacy benefit management companies, and government programs such as Medicare and Medicaid; coverage and reimbursement determinations by such payers and new policies and procedures adopted by such payers; competing drugs and product candidates that may be superior to, or more cost effective than, Regeneron’s Products and Regeneron’s Product Candidates; the extent to which the results from the research and development programs conducted by Regeneron and/or its collaborators may be replicated in other studies and/or lead to advancement of product candidates to clinical trials, therapeutic applications, or regulatory approval; the ability of Regeneron to manufacture and manage supply chains for multiple products and product candidates; the ability of Regeneron’s collaborators, suppliers, or other third parties (as applicable) to perform manufacturing, filling, finishing, packaging, labeling, distribution, and other steps related to Regeneron’s Products and Regeneron’s Product Candidates; unanticipated expenses; the costs of developing, producing, and selling products; the ability of Regeneron to meet any of its financial projections or guidance and changes to the assumptions underlying those projections or guidance; the potential for any license, collaboration, or supply agreement, including Regeneron’s agreements with Sanofi, Bayer, and Teva Pharmaceutical Industries Ltd. (or their respective affiliated companies, as applicable), to be cancelled or terminated; and risks associated with intellectual property of other parties and pending or future litigation relating thereto (including without limitation the patent litigation and other related proceedings relating to EYLEA^® (aflibercept) Injection, Dupixent^® (dupilumab), Praluent^® (alirocumab), and REGEN-COV^TM (casirivimab and imdevimab)), other litigation and other proceedings and government investigations relating to the Company and/or its operations, the ultimate outcome of any such proceedings and investigations, and the impact any of the foregoing may have on Regeneron’s business, prospects, operating results, and financial condition. A more complete description of these and other material risks can be found in Regeneron’s filings with the U.S. Securities and Exchange Commission, including its Form 10-K for the year ended December 31, 2020. Any forward-looking statements are made based on management’s current beliefs and judgment, and the reader is cautioned not to rely on any forward-looking statements made by Regeneron. Regeneron does not undertake any obligation to update (publicly or otherwise) any forward-looking statement, including without limitation any financial projection or guidance, whether as a result of new information, future events, or otherwise.

Regeneron uses its media and investor relations website and social media outlets to publish important information about the Company, including information that may be deemed material to investors. Financial and other information about Regeneron is routinely posted and is accessible on Regeneron’s media and investor relations website (http://newsroom.regeneron.com) and its Twitter feed (http://twitter.com/regeneron).

EX-99.2

Exhibit 99.2

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

Sanofi and Translate Bio initiate Phase 1/2 clinical trial of mRNA COVID-19 vaccine candidate

* Clinical trial to assess safety, immune response and reactogenicity, after preclinical data showed high neutralizing antibody levels

* Expected to enroll 415 participants; interim results expected in Q3 2021

* In parallel, preclinical studies are underway to evaluate additional mRNA candidates against emerging SARS-CoV-2 variants

PARIS and LEXINGTON, MASS. – March 12, 2021 - Sanofi Pasteur, the vaccines global business unit of Sanofi, and Translate Bio (NASDAQ: TBIO), a clinical-stage messenger RNA (mRNA) therapeutics company, today announced the start of the Phase 1/2 clinical trial for MRT5500, an mRNA vaccine candidate against SARS-CoV-2, the virus that causes COVID-19. The Companies expect interim results from this trial in the third quarter of 2021.

“Our mRNA vaccine candidate is the result of our expertise in infectious diseases coupled with the innovative technologies of our partner,” said Thomas Triomphe, Executive Vice President and Global Head of Sanofi Pasteur. “Initiating the Phase 1/2 trial represents an important step forward in our goal of bringing another effective vaccine to the ongoing fight against the COVID-19 pandemic.”

“We have made important progress towards developing mRNA vaccine candidates for infectious diseases through our collaboration with our partner Sanofi Pasteur,” said Ronald Renaud, Chief Executive Officer of Translate Bio. “With the impact of mRNA vaccines demonstrated during the pandemic, our joint development team remains steadfast in our commitment to advancing MRT5500 as part of the collaborative effort to overcome this global health crisis.”

Preclinical studies are ongoing and will continue over the next several months to evaluate whether MRT5500, as well as additional mRNA vaccine candidates, will induce neutralizing antibodies against the emerging SARS-CoV-2 variants, with the potential to inform current and future clinical development.

The joint development team is working on improving the temperature stability of the mRNA vaccine candidate and targeting a -20°C storage temperature for late-stage clinical trials and at launch. Efforts are also underway to enable the product to be stable at routine refrigerator temperature (2-8°C).

MRT5500 is being developed under a collaboration and license agreement between Sanofi Pasteur and Translate Bio.

About the Phase 1/2 clinical trial

The Phase 1/2 clinical trial is a randomized, double blind and placebo-controlled trial designed to evaluate the safety, reactogenicity (tolerability) and immunogenicity (immune response) of MRT5500, a COVID-19 vaccine candidate. A total of 415 healthy adults 18 years of age and older are expected to be enrolled in the trial across 13 investigational sites.

Clinical trial participants will receive one dose of MRT5500, or two doses 21 days apart. Three different dose levels will be investigated (15µg, 45µg or 135µg).

About previously-published preclinical results

Preclinical data showed that two immunizations of the mRNA vaccine induced high neutralizing antibody levels that are comparable to the upper range of those observed in infected humans.

About the Sanofi Pasteur and Translate Bio collaboration

In 2018, Translate Bio entered into a collaboration and exclusive license agreement with Sanofi Pasteur Inc., the vaccines global business unit of Sanofi, to develop mRNA vaccines for up to five infectious disease pathogens. The agreement was first expanded in March 2020 to include development of a novel mRNA vaccine for COVID-19. In June 2020, the two Companies built upon the existing collaboration to pursue novel mRNA vaccines to broadly address current and future infectious diseases.

This collaboration brings together Sanofi Pasteur’s leadership in vaccines and Translate Bio’s mRNA research and development expertise. Under the agreement, the Companies are jointly conducting research and development activities to advance mRNA infectious disease vaccine candidates and mRNA vaccine platform development during a research term of at least four years after the original signing in 2018.

Shots on goal in the fight against COVID-19

In addition to the mRNA vaccine candidate in collaboration with Translate Bio, Sanofi is collaborating with GSK on a COVID-19 vaccine candidate using the same recombinant protein-based manufacturing technology as one of Sanofi’s seasonal influenza vaccines, combined with GSK’s established pandemic adjuvant platform. On February 22, 2021, GSK and Sanofi announced the beginning of a new Phase 2 study with an improved antigen formulation. Enrollment of total 720 participants was completed on March 8. This vaccine is expected to be available in Q4 2021 pending Phase 3 outcomes and regulatory authorizations.

About Translate Bio

Translate Bio is a clinical-stage mRNA therapeutics company developing a new class of potentially transformative medicines to treat diseases caused by protein or gene dysfunction, or to prevent infectious diseases by generating protective immunity. Translate Bio is primarily focused on applying its technology to treat pulmonary diseases with a lead pulmonary candidate being evaluated as an inhaled treatment for cystic fibrosis (CF) in a Phase 1/2 clinical trial. Additional pulmonary diseases are being evaluated in discovery-stage research programs that utilize a proprietary lung delivery platform. Translate Bio also believes its technology may apply broadly to a wide range of diseases, including diseases that affect the liver. Additionally, the platform may be applied to various classes of treatments, such as therapeutic antibodies or protein degradation. Translate Bio is also pursuing the development of mRNA vaccines for infectious diseases under a collaboration with Sanofi Pasteur.

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 Nicolas Kressmann Tel.: +1 (732) 532 53-18 Nicolas.Kressmann@sanofi.com Translate Bio Media Relations Maura Gavaghan Tel: +1 (617) 233-1154 mgavaghan@translate.bio	Sanofi Investor Relations - Paris Eva Schaefer-Jansen Arnaud Delepine Yvonne Naughton Sanofi Investor Relations – North America Felix Lauscher Fara Berkowitz Suzanne Greco IR Main Line: Tel.: +33 (0)1 53 77 45 45 investor.relations@sanofi.com https://www.sanofi.com/en/investors/contact
	Translate Bio Investor Relations Teri Dahlman Tel: +1 (617) 817-8655 tdahlman@translate.bio

Sanofi Forward-Looking Statements

This press release 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 labelling and other matters that could affect the availability or commercial potential of such product candidates, the fact that product candidates if approved may not be commercially successful, the future approval and commercial success of therapeutic alternatives, Sanofi’s ability to benefit from external growth opportunities, to complete related transactions and/or obtain regulatory clearances, risks associated with intellectual property and any related pending or future litigation and the ultimate outcome of such litigation, trends in exchange rates and prevailing interest rates, volatile economic and market conditions, cost containment initiatives and subsequent changes thereto, and the impact that COVID-19 will have on us, our customers, suppliers, vendors, and other business partners, and the financial condition of any one of them, as well as on our employees and on the global economy as a whole. Any material effect of COVID-19 on any of the foregoing could also adversely impact us. This situation is changing rapidly and additional impacts may arise of which we are not currently aware and may exacerbate other previously identified risks. The risks and uncertainties also include the uncertainties 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, 2020. Other than as required by applicable law, Sanofi does not undertake any obligation to update or revise any forward-looking information or statements.

Translate Bio Cautionary Note Regarding Forward-Looking Statements

This press release contains forward-looking statements within the meaning of The Private Securities Litigation Reform Act of 1995. Such forward-looking statements include, but are not limited to, those regarding: the expected number of participants to be enrolled in the Phase 1/2 clinical trial of MRT5500; the plans to report interim results from the Phase 1/2 clinical trial of MRT5500 in the third quarter of 2021; plans and strategies to further advance MRT5500, including improvements to the temperature stability; the potential for MRT5500 to be a promising COVID-19 vaccine candidate; the potential for mRNA vaccine approaches to effectively address COVID-19 and any new SARS-CoV-2 variants; the expected benefits of Translate Bio’s collaboration with Sanofi; Translate Bio’s beliefs regarding the broad applicability of its technology; and Translate Bio’s plans, strategies and prospects for its business, including its lead development programs and continued development of mRNA vaccines for the treatment of infectious diseases. The words “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “forward,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “should,” “target,” “would” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Such statements are subject to numerous important factors, risks and uncertainties that may cause actual events or results to differ materially from current expectations and beliefs, including but not limited to: the current and potential future impacts of the COVID-19 pandemic on Translate Bio’s business, financial condition, operations and liquidity; Translate Bio’s ability to advance the development of its platform and programs, including without limitation its vaccine development program generally and MRT5500 specifically, under the timelines it projects, demonstrate the requisite safety and efficacy of its product candidates and replicate in clinical trials any positive findings from preclinical studies; the successful advancement of the collaboration agreement between Translate Bio and Sanofi; uncertainties relating to the discovery and development of vaccine candidates based on mRNA, and specifically as it relates to COVID-19; the content and timing of decisions made by the U.S. Food and Drug Administration (“FDA”), other regulatory authorities and investigational review boards at clinical trial sites, including decisions as it relates to ongoing and planned clinical trials; Translate Bio’s ability to obtain, maintain and enforce necessary patent and other intellectual property protection; the availability of significant cash required to fund operations; competitive factors; general economic and market conditions and other important risk factors set forth under the caption “Risk Factors” in Translate Bio’s Annual Report on Form 10-K for the full year ended December 31, 2020 filed with the Securities and Exchange Commission (“SEC”) on March 1, 2021 and in any other subsequent filings made by Translate Bio. Any forward-looking statements contained in this press release speak only as of the date hereof, and Translate Bio specifically disclaims any obligation to update any forward-looking statement, whether as a result of new information, future events or otherwise.