Dupixent® (dupilumab) Approved in the European Union as the First and Only Medicine for Young Children with Eosinophilic Esophagitis

Rhea-AI Summary

Regeneron Pharmaceuticals and Sanofi announced European Commission approval of Dupixent (dupilumab) for treating eosinophilic esophagitis (EoE) in children aged 1 to 11 years weighing at least 15 kg. The approval is based on Phase 3 trial results showing 68% of children achieved histological disease remission at 16 weeks compared to 3% on placebo. The treatment demonstrated an 86% reduction in peak esophageal intraepithelial eosinophil count from baseline. This makes Dupixent the first and only medicine approved in the EU for treating EoE in young children who are inadequately controlled by conventional therapy.

Positive

• First-ever EU-approved medicine for treating EoE in young children
• 68% of treated children achieved histological disease remission vs 3% for placebo
• 86% reduction in peak esophageal intraepithelial eosinophil count
• Sustained efficacy results for up to one year
• Expansion of existing market with new age group approval

Negative

• Adverse reactions including COVID-19, nausea, injection site pain and headache reported in ≥10% of treated children
• to patients weighing at least 15 kg

Insights

Medical Research Analyst

The EU approval of Dupixent for pediatric EoE represents a significant breakthrough in treating this challenging condition. The Phase 3 trial data showed remarkable efficacy with 68% of treated children achieving histological disease remission versus just 3% for placebo. The 86% reduction in eosinophil count demonstrates strong disease-modifying potential.

This approval addresses a critical unmet need, as up to 50% of children with EoE in the EU remain uncontrolled with conventional therapies. The sustained efficacy over one year and consistent safety profile strengthen Dupixent's position as a transformative treatment option. For Regeneron and Sanofi, this expanded indication opens up a new market segment and reinforces Dupixent's leadership in treating type 2 inflammatory diseases.

Market Research Analyst

This approval significantly expands Dupixent's addressable market in the EU, building on its existing EoE approval for adults and adolescents. The first-mover advantage in pediatric EoE, combined with strong efficacy data and competition, positions Dupixent for continued market dominance. The weight-based dosing regimen ensures optimal treatment across different patient sizes, potentially driving higher per-patient revenue.

With Dupixent already approved for this indication in the US and Canada, the EU approval completes major market coverage and should accelerate revenue growth. The drug's expanding indications and strong safety profile continue to support its blockbuster status and Regeneron's market position.

Approval based on Phase 3 data showing significantly more children aged 1 to 11 years on Dupixent achieved histological disease remission at 16 weeks compared to placebo, which was sustained up to one year

Dupixent is the first-ever medicine in the EU indicated to treat these young patients, who persistently struggle to eat at a critical stage in life where growth is crucial

TARRYTOWN, N.Y. and PARIS, Nov. 06, 2024 (GLOBE NEWSWIRE) -- Regeneron Pharmaceuticals, Inc. (NASDAQ: REGN) and Sanofi today announced that the European Commission (EC) has approved Dupixent^® (dupilumab) to treat eosinophilic esophagitis (EoE) in children as young as 1 year of age. Specifically, the approval covers children aged 1 to 11 years who weigh at least 15 kg and who are inadequately controlled by, intolerant to, or who are not candidates for conventional medicinal therapy. This expands the initial approval in the European Union (EU) for EoE in adults and adolescents and makes Dupixent the first and only medicine indicated to treat these young patients. Dupixent is also approved in this young age group in the U.S. and Canada.

“Young children with eosinophilic esophagitis are at the beginning of their life-long journey with a disease that challenges their ability to eat,” said Roberta Giodice, President, ESEO Italia. “Parents of these children have often relied on restrictive diets that do not specifically address the disease and can stunt their growth at a critical time in development that could impact them for years to come. We are pleased that research continues and offers new treatment options to improve the quality of their care.”

“Eosinophilic esophagitis presents a unique challenge in young children, who struggle with their basic ability to eat during a time in their lives where proper nutrition is essential for growth and development,” said George D. Yancopoulos, M.D., Ph.D., Board co-Chair, President and Chief Scientific Officer at Regeneron, and a principal inventor of Dupixent. “This approval will bring the proven efficacy and demonstrated safety profile of Dupixent to this vulnerable, young population that has already been established in older EoE patients and has the potential to transform the standard of care for children with EoE who previously had no therapies specifically approved for them.”

The approval is based on the two-part (Part A and B) EoE KIDS Phase 3 trial in children aged 1 to 11 years, which established a bridge showing the response to Dupixent in children with EoE is similar to that of the approved adult and adolescent populations. In Part A, children who received a higher dose of Dupixent (n=37) based on a weight-based dosing regimen experienced the following outcomes, compared to placebo (n=34) at 16 weeks:

• 68% achieved histological disease remission (≤6 eosinophils/high power field) compared to 3%, the primary endpoint. These results were sustained for up to one year in Part B of the trial.
• 86% reduction in peak esophageal intraepithelial eosinophil count from baseline compared to a 21% increase.
• Reductions in abnormal endoscopic findings and disease severity and extent (as measured at the microscopic level).
• Nominally significant improvement in the frequency and severity of EoE signs, and numerical reduction in days with at least one sign of EoE, based on caregiver-reported outcomes.

The safety results in the EoE KIDS trial were generally consistent with the known safety profile of Dupixent in adolescents and adults with EoE. The most common adverse reactions for Dupixent overall are injection site reactions, conjunctivitis, conjunctivitis allergic, arthralgia, oral herpes and eosinophilia. In addition, the adverse reaction of injection site bruising was reported in EoE. In patients aged 1 to 11 years, adverse events more commonly observed with Dupixent (≥10%) in either weight-based dosing regimen compared to placebo during Part A were COVID-19, nausea, injection site pain and headache. The long-term safety profile of Dupixent evaluated in Part B was similar to that observed during Part A.

“Up to half of all children in the EU with eosinophilic esophagitis remain uncontrolled despite existing standard of care treatment options, and, as a result, many of these young patients struggle to maintain weight due to serious symptoms such as difficulty swallowing and vomiting,” said Houman Ashrafian, M.D., Ph.D., Executive Vice President, Head of Research and Development at Sanofi. “This milestone provides an important new treatment for pediatric patients who were previously without options specifically approved for their disease. With this novel approach to addressing an underlying cause of eosinophilic esophagitis, Dupixent has the potential to give these young children a better chance to thrive.”

About Eosinophilic Esophagitis
EoE is a chronic, progressive disease associated with type 2 inflammation that is thought to be responsible for damaging the esophagus and impairing its function. Diagnosis is difficult, as symptoms can be mistaken for other conditions leading to delays in diagnosis. EoE can severely impact a child’s ability to eat and may also cause vomiting, abdominal pain, difficulty swallowing, decreased appetite and challenges thriving. Continuous management of EoE may be needed to reduce the risk of complications and disease progression.

About the Dupixent Pediatric Eosinophilic Esophagitis Trial
The EoE KIDS Phase 3 trial was a randomized, double-blind, placebo-controlled trial evaluating the efficacy and safety of Dupixent in children aged 1 to 11 years with EoE. Part A enrolled 71 patients and evaluated Dupixent at a weight-based dose regimen, compared to placebo, for 16 weeks. Part B was a 36-week extended active treatment period in which eligible children from Part A in the Dupixent group continued treatment, while those in the placebo group switched to Dupixent. Patients included in this trial were previously treated and did not respond to conventional medicinal therapies, including proton pump inhibitors and/or swallowed topical corticosteroids.

The primary endpoint was histologic remission at 16 weeks, and secondary endpoints included assessments of endoscopic and histopathologic measures of the severity of disease along with caregiver-reported clinical signs and symptoms of EoE. The 108-week open-label extension period (Part C) to evaluate longer-term outcomes was recently completed.

Results from the trial were published in The New England Journal of Medicine.

About Dupixent
Dupixent is an injection administered under the skin (subcutaneous injection) at different injection sites. In patients aged 1 to 11 years with EoE, Dupixent is administered every other week (200 mg for children ≥15 to <30 kg, 300 mg for children ≥30 to <40 kg) or every week (300 mg for children ≥40 kg), based on weight. Dupixent is intended for use under the guidance of a healthcare professional and can be given in a clinic or at home administered by a caregiver after training by a healthcare professional.

Dupixent, which was invented using Regeneron’s proprietary VelocImmune^® technology, is a fully human monoclonal antibody that inhibits the signaling of the interleukin-4 (IL-4) and interleukin-13 (IL-13) pathways and is not an immunosuppressant. The Dupixent development program has shown significant clinical benefit and a decrease in type 2 inflammation in Phase 3 trials, establishing that IL-4 and IL-13 are two of the key and central drivers of the type 2 inflammation that plays a major role in multiple related and often co-morbid diseases.

Dupixent has received regulatory approvals in more than 60 countries in one or more indications including certain patients with atopic dermatitis, asthma, chronic rhinosinusitis with nasal polyps (CRSwNP), eosinophilic esophagitis (EoE), prurigo nodularis, chronic spontaneous urticaria (CSU), and chronic obstructive pulmonary disease (COPD) in different age populations. More than 1,000,000 patients are being treated with Dupixent globally.¹

About Regeneron’s VelocImmune Technology 
Regeneron's VelocImmune technology utilizes a proprietary genetically engineered mouse platform endowed with a genetically humanized immune system to produce optimized fully human antibodies. When Regeneron's co-Founder, President and Chief Scientific Officer George D. Yancopoulos was a graduate student with his mentor Frederick W. Alt in 1985, they were the first to envision making such a genetically humanized mouse, and Regeneron has spent decades inventing and developing VelocImmune and related VelociSuite^® technologies. Dr. Yancopoulos and his team have used VelocImmune technology to create a substantial proportion of all original, FDA-approved or authorized fully human monoclonal antibodies. This includes REGEN-COV^® (casirivimab and imdevimab), Dupixent, Libtayo^® (cemiplimab-rwlc), Praluent^® (alirocumab), Kevzara^® (sarilumab), Evkeeza^® (evinacumab-dgnb), Inmazeb^® (atoltivimab, maftivimab and odesivimab-ebgn) and Veopoz™ (pozelimab-bbfg).

Dupilumab Development Program 
Dupilumab is being jointly developed by Regeneron and Sanofi under a global collaboration agreement. To date, dupilumab has been studied across more than 60 clinical trials involving more than 10,000 patients with various chronic diseases driven in part by type 2 inflammation. 

In addition to the currently approved indications, Regeneron and Sanofi are studying dupilumab in a broad range of diseases driven by type 2 inflammation or other allergic processes in Phase 3 trials, including chronic pruritus of unknown origin and bullous pemphigoid. These potential uses of dupilumab are currently under clinical investigation, and the safety and efficacy in these conditions have not been fully evaluated by any regulatory authority. 

U.S. INDICATIONS 
DUPIXENT is a prescription medicine used:

• to treat adults and children 6 months of age and older with moderate-to-severe eczema (atopic dermatitis or AD) that is not well controlled with prescription therapies used on the skin (topical), or who cannot use topical therapies. DUPIXENT can be used with or without topical corticosteroids. It is not known if DUPIXENT is safe and effective in children with atopic dermatitis under 6 months of age.
• with other asthma medicines for the maintenance treatment of moderate-to-severe eosinophilic or oral steroid dependent asthma in adults and children 6 years of age and older whose asthma is not controlled with their current asthma medicines. DUPIXENT helps prevent severe asthma attacks (exacerbations) and can improve your breathing. DUPIXENT may also help reduce the amount of oral corticosteroids you need while preventing severe asthma attacks and improving your breathing. It is not known if DUPIXENT is safe and effective in children with asthma under 6 years of age.
• with other medicines for the maintenance treatment of chronic rhinosinusitis with nasal polyps (CRSwNP) in adults and children 12 years of age and older whose disease is not controlled. It is not known if DUPIXENT is safe and effective in children with chronic rhinosinusitis with nasal polyps under 12 years of age.
• to treat adults and children 1 year of age and older with eosinophilic esophagitis (EoE), who weigh at least 33 pounds (15 kg). It is not known if DUPIXENT is safe and effective in children with eosinophilic esophagitis under 1 year of age, or who weigh less than 33 pounds (15 kg).
• to treat adults with prurigo nodularis (PN). It is not known if DUPIXENT is safe and effective in children with prurigo nodularis under 18 years of age.
• with other medicines for the maintenance treatment of adults with inadequately controlled chronic obstructive pulmonary disease (COPD) and a high number of blood eosinophils (a type of white blood cell that may contribute to your COPD). DUPIXENT is used to reduce the number of flare-ups (the worsening of your COPD symptoms for several days) and can improve your breathing. It is not known if DUPIXENT is safe and effective in children with chronic obstructive pulmonary disease under 18 years of age.

DUPIXENT is not used to relieve sudden breathing problems and will not replace an inhaled rescue medicine.

IMPORTANT SAFETY INFORMATION

Do not use if you are allergic to dupilumab or to any of the ingredients in DUPIXENT®.

Before using DUPIXENT, tell your healthcare provider about all your medical conditions, including if you:

• have eye problems.
• have a parasitic (helminth) infection.
• are scheduled to receive any vaccinations. You should not receive a “live vaccine” right before and during treatment with DUPIXENT.
• are pregnant or plan to become pregnant. It is not known whether DUPIXENT will harm your unborn baby.
  • A pregnancy registry for women who take DUPIXENT during pregnancy collects information about the health of you and your baby. To enroll or get more information call 1-877-311-8972 or go to https://mothertobaby.org/ongoing-study/dupixent/.
• are breastfeeding or plan to breastfeed. It is not known whether DUPIXENT passes into your breast milk.

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

Especially tell your healthcare provider if you are taking oral, topical, or inhaled corticosteroid medicines; have asthma and use an asthma medicine; or have atopic dermatitis, chronic rhinosinusitis with nasal polyps, eosinophilic esophagitis, prurigo nodularis, or chronic obstructive pulmonary disease and also have asthma. Do not change or stop your other medicines, including corticosteroid medicine or other asthma medicine, without talking to your healthcare provider. This may cause other symptoms that were controlled by those medicines to come back.

DUPIXENT can cause serious side effects, including:

• Allergic reactions. DUPIXENT can cause allergic reactions that can sometimes be severe. Stop using DUPIXENT and tell your healthcare provider or get emergency help right away if you get any of the following signs or symptoms: breathing problems or wheezing, swelling of the face, lips, mouth, tongue or throat, fainting, dizziness, feeling lightheaded, fast pulse, fever, hives, joint pain, general ill feeling, itching, skin rash, swollen lymph nodes, nausea or vomiting, or cramps in your stomach-area.
• Eye problems. Tell your healthcare provider if you have any new or worsening eye problems, including eye pain or changes in vision, such as blurred vision. Your healthcare provider may send you to an ophthalmologist for an exam if needed.
• Inflammation of your blood vessels. Rarely, this can happen in people with asthma who receive DUPIXENT. This may happen in people who also take a steroid medicine by mouth that is being stopped or the dose is being lowered. It is not known whether this is caused by DUPIXENT. Tell your healthcare provider right away if you have: rash, chest pain, worsening shortness of breath, a feeling of pins and needles or numbness of your arms or legs, or persistent fever.
• Joint aches and pain. Some people who use DUPIXENT have had trouble walking or moving due to their joint symptoms, and in some cases needed to be hospitalized. Tell your healthcare provider about any new or worsening joint symptoms. Your healthcare provider may stop DUPIXENT if you develop joint symptoms.

The most common side effects include:

• Eczema: injection site reactions, eye and eyelid inflammation, including redness, swelling, and itching, sometimes with blurred vision, dry eye, cold sores in your mouth or on your lips, and high count of a certain white blood cell (eosinophilia).
• Asthma: injection site reactions, high count of a certain white blood cell (eosinophilia), pain in the throat (oropharyngeal pain), and parasitic (helminth) infections.
• Chronic Rhinosinusitis with Nasal Polyps: injection site reactions, eye and eyelid inflammation, including redness, swelling, and itching, sometimes with blurred vision, high count of a certain white blood cell (eosinophilia), gastritis, joint pain (arthralgia), trouble sleeping (insomnia), and toothache.
• Eosinophilic Esophagitis: injection site reactions, upper respiratory tract infections, cold sores in your mouth or on your lips, and joint pain (arthralgia).
• Prurigo Nodularis: eye and eyelid inflammation, including redness, swelling, and itching, sometimes with blurred vision, herpes virus infections, common cold symptoms (nasopharyngitis), dizziness, muscle pain, and diarrhea.
• Chronic Obstructive Pulmonary Disease: injection site reactions, common cold symptoms (nasopharyngitis), high count of a certain white blood cell (eosinophilia), viral infection, back pain, inflammation inside the nose (rhinitis), diarrhea, gastritis, joint pain (arthralgia), toothache, headache, and urinary tract infection.

Tell your healthcare provider if you have any side effect that bothers you or that does not go away. These are not all the possible side effects of DUPIXENT. Call your doctor for medical advice about side effects. You are encouraged to report negative side effects of prescription drugs to the FDA. Visit www.fda.gov/medwatch, or call 1-800-FDA-1088.

Use DUPIXENT exactly as prescribed by your healthcare provider. It’s an injection given under the skin (subcutaneous injection). Your healthcare provider will decide if you or your caregiver can inject DUPIXENT. Do not try to prepare and inject DUPIXENT until you or your caregiver have been trained by your healthcare provider. In children 12 years of age and older, it’s recommended DUPIXENT be administered by or under supervision of an adult. In children 6 months to less than 12 years of age, DUPIXENT should be given by a caregiver.

Please see accompanying full Prescribing Information including Patient Information.

About Regeneron
Regeneron (NASDAQ: REGN) is a leading biotechnology company that invents, develops and commercializes life-transforming medicines for people with serious diseases. Founded and led by physician-scientists, our unique ability to repeatedly and consistently translate science into medicine has led to numerous approved treatments and product candidates in development, most 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, neurological diseases, hematologic conditions, infectious diseases, and rare diseases.

Regeneron pushes the boundaries of scientific discovery and accelerates drug development using our proprietary technologies, such as VelociSuite^®, which produces optimized fully human antibodies and new classes of bispecific antibodies. We are shaping the next frontier of medicine with data-powered insights from the Regeneron Genetics Center^® and pioneering genetic medicine platforms, enabling us to identify innovative targets and complementary approaches to potentially treat or cure diseases.

For more information, please visit www.Regeneron.com or follow Regeneron on LinkedIn, Instagram, Facebook or X.

About Sanofi 
We are an innovative global healthcare company, driven by one purpose: we chase the miracles of science to improve people’s lives. Our team, across the world, is dedicated to transforming the practice of medicine by working to turn the impossible into the possible. We provide potentially life-changing treatment options and life-saving vaccine protection to millions of people globally, while putting sustainability and social responsibility at the center of our ambitions.

Sanofi is listed on EURONEXT: SAN and NASDAQ: SNY.

Regeneron Forward-Looking Statements and Use of Digital Media 
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 nature, timing, and possible success and therapeutic applications of products marketed or otherwise commercialized by Regeneron and/or its collaborators or licensees (collectively, “Regeneron’s Products”) and product candidates being developed by Regeneron and/or its collaborators or licensees (collectively, “Regeneron’s Product Candidates”) and research and clinical programs now underway or planned, including without limitation Dupixent^® (dupilumab) for the treatment of children aged 1 to 11 years with eosinophilic esophagitis; uncertainty of the utilization, 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 any of the foregoing; 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 Dupixent for the treatment of chronic pruritus of unknown origin, bullous pemphigoid, and other potential indications; the ability of Regeneron’s collaborators, licensees, 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; the ability of Regeneron to manage supply chains for multiple products and product candidates; safety issues resulting from the administration of Regeneron’s Products (such as Dupixent) 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 or licensees may be replicated in other studies and/or lead to advancement of product candidates to clinical trials, therapeutic applications, or regulatory approval; 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 and Bayer (or their respective affiliated companies, as applicable) to be cancelled or terminated; the impact of public health outbreaks, epidemics, or pandemics (such as the COVID-19 pandemic) on Regeneron's business; 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), other litigation and other proceedings and government investigations relating to the Company and/or its operations (including the pending civil proceedings initiated or joined by the U.S. Department of Justice and the U.S. Attorney's Office for the District of Massachusetts), 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, 2023 and its Form 10-Q for the quarterly period ended September 30, 2024. 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 (https://investor.regeneron.com) and its LinkedIn page (https://www.linkedin.com/company/regeneron-pharmaceuticals).

Sanofi Disclaimers or 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 pandemics or other global crises may 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. 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, 2023. Other than as required by applicable law, Sanofi does not undertake any obligation to update or revise any forward-looking information or statements.    

All trademarks mentioned in this press release are the property of the Sanofi group apart from VelociSuite and Regeneron Genetics Center.

Regeneron Contacts:  Media Relations  Hannah Kwagh Tel: +1 914-847-6314 Hannah.Kwagh@regeneron.com   Sanofi Contacts:  Media Relations  Sandrine Guendoul Tel: +33 6 25 09 14 25 Sandrine.Guendoul@sanofi.com Evan Berland Tel: +1 215-432-0234 Evan.Berland@sanofi.com Victor Rouault   Tel: +33 6 70 93 71 40 Victor.Rouault@sanofi.com   Timothy Gilbert Tel: +1 516-521-2929 Timothy.Gilbert@sanofi.com

Investor Relations  Mark Hudson Tel: +1 914-847-3482  Mark.Hudson@regeneron.com Investor Relations  Thomas Kudsk Larsen Tel: +44 7545 513 693 Thomas.Larsen@sanofi.com Alizé Kaisserian Tel: +33 6 47 04 12 11 Alize.Kaisserian@sanofi.com Arnaud Delépine Tel: +33 6 73 69 36 93 Arnaud.Delepine@sanofi.com Felix Lauscher  Tel: +1 908-612-7239  Felix.Lauscher@sanofi.com  Keita Browne Tel: +1 781-249-1766 Keita.Browne@sanofi.com Nathalie Pham  Tel: +33 7 85 93 30 17  Nathalie.Pham@sanofi.com Tarik Elgoutni  Tel: +1 617-710-3587  Tarik.Elgoutni@sanofi.com Thibaud Châtelet  Tel: +33 6 80 80 89 90  Thibaud.Chatelet@sanofi.com

---

¹ Data on File

FAQ

What are the efficacy results of Dupixent (REGN) in children with EoE?

In the Phase 3 trial, 68% of children treated with Dupixent achieved histological disease remission at 16 weeks compared to 3% on placebo, with an 86% reduction in peak esophageal intraepithelial eosinophil count.

What age group received EU approval for Dupixent (REGN) in EoE treatment?

The European Commission approved Dupixent for treating eosinophilic esophagitis in children aged 1 to 11 years who weigh at least 15 kg.

What are the common side effects of Dupixent (REGN) in children with EoE?

Common side effects in children included COVID-19, nausea, injection site pain and headache, observed in ≥10% of treated patients compared to placebo.