Dupixent® (dupilumab) Approved in the U.S. as the First New Targeted Therapy in Over a Decade for Chronic Spontaneous Urticaria (CSU)

Rhea-AI Summary

Regeneron Pharmaceuticals (NASDAQ: REGN) and Sanofi announced FDA approval of Dupixent® (dupilumab) for treating chronic spontaneous urticaria (CSU) in adults and adolescents aged 12+ who remain symptomatic despite antihistamine treatment. This marks the first new targeted therapy for CSU in over a decade.

The approval is supported by two Phase 3 trials (Study A with 136 patients and Study C with 148 patients) that demonstrated significant reductions in itch severity and urticaria activity compared to placebo at 24 weeks. An additional Study B (108 patients) provided safety data for patients who were inadequate responders to anti-IgE therapy.

This represents Dupixent's seventh FDA-approved indication for conditions driven by type 2 inflammation. The treatment will target over 300,000 U.S. adults and adolescents with CSU who remain symptomatic despite antihistamine treatment. The most common adverse event was injection site reactions.

Positive

• First new targeted CSU therapy approval in over 10 years, expanding market opportunity
• Targets large market of 300,000+ eligible patients in the U.S.
• Successful Phase 3 trial results demonstrating significant efficacy
• Seventh FDA-approved indication for Dupixent, showing strong portfolio expansion
• Potential for treating multiple related conditions simultaneously

Negative

• to injection site reactions as common adverse events
• Requires regulatory approvals in other major markets like EU

Insights

Pharmaceutical Industry Analyst

Dupixent's FDA approval for CSU represents meaningful revenue growth and strengthens Regeneron's immunology franchise while addressing significant unmet medical need.

The FDA approval of Dupixent for chronic spontaneous urticaria (CSU) marks a significant commercial opportunity for Regeneron and partner Sanofi. With over 300,000 potential patients in the U.S. alone who remain symptomatic despite antihistamine treatment, this approval taps into a substantial market that has seen no new targeted therapies in over a decade.

This represents Dupixent's seventh approved indication for type 2 inflammatory conditions, further cementing its position as a versatile blockbuster biologic. The strategic value here is compelling - by expanding into adjacent indications with similar underlying biology, Regeneron maximizes Dupixent's commercial potential while leveraging established manufacturing, marketing, and safety data.

Particularly noteworthy is the potential for cross-utilization among patients with multiple inflammatory conditions. The article specifically mentions that several conditions treatable with Dupixent (like atopic dermatitis and asthma) can co-occur with CSU, creating efficiency in treatment paradigms and potentially enhancing prescription rates.

From a competitive standpoint, being first to market in over a decade gives Dupixent a significant advantage in CSU treatment. The chronic nature of CSU means patients typically require long-term therapy, translating to sustained revenue streams. With global approvals already secured in Japan, UAE, and Brazil, and more pending, the international expansion further amplifies growth potential.

Medical Specialist

Dupixent meets critical unmet need in CSU with strong efficacy data, expanding treatment options for a debilitating condition resistant to standard therapies.

The approval of Dupixent for chronic spontaneous urticaria addresses a significant therapeutic gap for a condition characterized by unpredictable, severe itching and hives that substantially impact quality of life. The clinical significance cannot be overstated - until now, patients who failed to respond to antihistamines had extremely options.

The Phase 3 data supporting this approval demonstrated meaningful reductions in both itch severity and urticaria activity (composite of itch and hives) compared to placebo at 24 weeks. Importantly, Dupixent also increased the likelihood of well-controlled disease or complete response - outcomes that matter tremendously to patients suffering from this condition.

What's particularly valuable about this approval is the mechanism of action targeting the underlying type 2 inflammation rather than just symptom management. For the substantial population of patients with inadequate response to antihistamines, Dupixent offers a fundamentally different approach by addressing disease pathophysiology.

The consistent safety profile across indications is reassuring, with injection site reactions being the most common adverse event. This favorable benefit-risk profile should support rapid clinical adoption, especially given the established safety record in other inflammatory conditions.

The inclusion of adolescents aged 12+ in this approval is also significant, as it enables earlier intervention in a condition that can persist for years and have profound effects on development, schooling, and social functioning. This comprehensive approach to a challenging condition represents a meaningful advancement in the treatment landscape.

Approval based on Phase 3 trials demonstrating Dupixent significantly reduced itch and hives compared to placebo

In the U.S., there are more than 300,000 adults and adolescents aged 12 years and older living with CSU who remain symptomatic despite antihistamine treatment

CSU is the seventh disease with underlying type 2 inflammation in which Dupixent is approved

TARRYTOWN, N.Y. and PARIS, April 18, 2025 (GLOBE NEWSWIRE) -- Regeneron Pharmaceuticals, Inc. (NASDAQ: REGN) and Sanofi today announced that the U.S. Food and Drug Administration (FDA) has approved Dupixent^® (dupilumab) for the treatment of adults and adolescents aged 12 years and older with chronic spontaneous urticaria (CSU) who remain symptomatic despite histamine-1 (H1) antihistamine treatment.

“People with chronic spontaneous urticaria experience sudden, unpredictable hives and severe itch that cause a significant, and often overwhelming, burden on their everyday lives,” said Kenneth Mendez, President and Chief Executive Officer at the Asthma and Allergy Foundation of America. “The approval of this treatment offers patients more options and the chance to control their disease.”

“Dupixent is the first new targeted treatment for chronic spontaneous urticaria, or CSU, in over ten years, with pivotal trials demonstrating its ability to help patients significantly reduce the hallmark symptoms of intense itch and unpredictable hives associated with this disease,” said George D. Yancopoulos, M.D., Ph.D., Board co-Chair, President and Chief Scientific Officer at Regeneron, and a principal inventor of Dupixent. “With this FDA decision, Dupixent is now approved for seven chronic, debilitating atopic conditions driven in part by underlying type 2 inflammation, several of which have been shown to co-morbidly occur with CSU, such as atopic dermatitis and asthma – providing patients with one treatment that might help multiple atopy conditions. We look forward to bringing Dupixent to the more than 300,000 CSU patients in the U.S. with inadequately controlled disease on standard-of-care treatment who, until now, had limited treatment options.”

The U.S. approval is based on data from two Phase 3 clinical trials, Study A (n=136) and Study C (n=148), which included biologic-naïve patients aged 12 years and older who were symptomatic despite the use of antihistamines and assessed Dupixent as an add-on therapy to standard-of-care antihistamines, compared to antihistamines alone. Both trials met their primary and key secondary endpoints with Dupixent demonstrating reductions in itch severity and urticaria activity (a composite of itch and hives) compared to placebo at 24 weeks. Dupixent also increased the likelihood of well-controlled disease or complete response compared to placebo at 24 weeks. Study B (n=108) provided additional safety data and evaluated Dupixent in patients aged 12 years and older who were inadequate responders or intolerant to anti-IgE therapy and symptomatic despite antihistamine use.

Safety results from Study A, Study B and Study C were generally consistent with the known safety profile of Dupixent in its approved indications. In pooled data from all three trials, the most common adverse event (≥2%) more frequently observed in patients on Dupixent compared to placebo was injection site reactions.

“CSU patients with uncontrolled disease experience highly burdensome itch and hives that can significantly disrupt daily living,” said Alyssa Johnsen, M.D., Ph.D., Global Therapeutic Area Head, Immunology and Oncology Development at Sanofi. “This FDA approval provides a new treatment option to help address the underlying drivers of these severe and recurring signs and symptoms. Dupixent has the potential to improve outcomes for CSU patients who previously had limited treatment options.”

Dupixent is already approved for CSU in Japan, the United Arab Emirates (UAE) and Brazil. Submissions are currently under review with other regulatory authorities around the world including in the European Union.

About Chronic Spontaneous Urticaria
CSU is a chronic inflammatory skin disease driven in part by type 2 inflammation, which causes sudden and debilitating hives and recurring itch. CSU is typically treated with H1 antihistamines, medicines that target H1 receptors on cells to control symptoms of itch and urticaria. However, the disease remains uncontrolled despite antihistamine treatment in many patients, some of whom are left with limited alternative treatment options. These individuals continue to experience symptoms that can be debilitating and significantly impact their quality of life. More than 300,000 people in the U.S. suffer from CSU that is inadequately controlled by antihistamines.

About the Dupixent CSU Phase 3 Trial Program
The LIBERTY-CUPID Phase 3 program evaluating Dupixent for CSU consists of Study A, Study B and Study C. These trials were randomized, double-blind, placebo-controlled clinical trials that evaluated the efficacy and safety of Dupixent as an add-on therapy to standard-of-care antihistamines compared to antihistamines alone. Studies A and C were replicate trials that assessed patients aged 6 years and older who remained symptomatic despite the use of antihistamines. Study B was conducted in patients aged 12 years and older who were symptomatic despite use of antihistamines and were inadequate responders or intolerant to anti-IgE therapy. During the 24-week treatment period in all three trials, patients received an initial loading dose followed by 300 mg Dupixent every two weeks, except for pediatric patients weighing <60 kg who received 200 mg every two weeks.

In all three studies, the primary endpoint assessed the change from baseline in itch at 24 weeks (measured by the weekly itch severity score [ISS7], 0-21 scale). The key secondary endpoints (also assessed at 24 weeks) included change from baseline in itch and hives (weekly urticaria activity score [UAS7], 0-42 scale). Additional secondary endpoints assessed at 24 weeks evaluated the proportion of patients achieving well-controlled disease status (UAS7 ≤6) and the proportion of patients with complete response (UAS7=0).

The results from Studies A and B were published in The Journal of Allergy and Clinical Immunology. Study B did not meet the primary endpoint in the U.S. of reduction in ISS7 compared to placebo at 24 weeks.

About Dupixent
Dupixent is an injection administered under the skin (subcutaneous injection) at different injection sites. In adults with CSU who remain symptomatic despite H1 antihistamine treatment, Dupixent 300 mg is administered every two weeks after an initial loading dose. In patients aged 12 to 17 years with CSU who remain symptomatic despite H1 antihistamine treatment, Dupixent is administered every two weeks based on weight (200 mg for adolescents ≥30 to <60 kg, 300 mg for adolescents ≥60 kg) after an initial loading dose. Dupixent is intended for use under the guidance of a healthcare professional and can be given in a clinic or at home after training by a healthcare professional. In adolescents aged 12 to 17 years, Dupixent should be administered under the supervision of an adult.

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.

Regeneron and Sanofi are committed to helping patients in the U.S. who are prescribed Dupixent gain access to the medicine and receive the support they may need with the DUPIXENT MyWay^® program. For more information, please call 1-844-DUPIXENT (1-844-387-4936) or visit www.DUPIXENT.com.

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, 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 fully human monoclonal antibodies. This includes Dupixent^® (dupilumab), Libtayo^® (cemiplimab-rwlc), Praluent^® (alirocumab), Kevzara^® (sarilumab), Evkeeza^® (evinacumab-dgnb), Inmazeb^® (atoltivimab, maftivimab and odesivimab-ebgn) and Veopoz^® (pozelimab-bbfg). In addition, REGEN-COV^® (casirivimab and imdevimab) had been authorized by the FDA during the COVID-19 pandemic until 2024.

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, bullous pemphigoid and lichen simplex chronicus. 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.
• to treat adults and children 12 years of age and older with chronic spontaneous urticaria (CSU) who continue to have hives that are not controlled with H1 antihistamine treatment. It is not known if DUPIXENT is safe and effective in children with chronic spontaneous urticaria under 12 years of age, or who weigh less than 66 pounds (30 kg).

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

DUPIXENT is not used to treat any other forms of hives (urticaria).

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, chronic obstructive pulmonary disease, or chronic spontaneous urticaria, 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. Tell your healthcare provider right away if you have: rash, chest pain, worsening shortness of breath, brown or dark colored urine, persistent fever, or a feeling of pins and needles or numbness of your arms or legs.
• Psoriasis. This can happen in people with atopic dermatitis and asthma who receive DUPIXENT. Tell your healthcare provider about any new skin symptoms. Your healthcare provider may send you to a dermatologist for an examination if needed.
• 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.
• Chronic Spontaneous Urticaria: injection site reactions.

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 chronic spontaneous urticaria (“CSU”); 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 CSU in the European Union as well as for the treatment of chronic pruritus of unknown origin, bullous pemphigoid, lichen simplex chronicus, 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; changes in laws, regulations, and policies affecting the healthcare industry; competing drugs and product candidates that may be superior to, or more cost effective than, Regeneron’s Products and Regeneron’s Product Candidates (including biosimilar versions of Regeneron’s Products); 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 on Regeneron's business; and risks associated with 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), 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), 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. 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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).

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Regeneron Contacts:
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¹ Data on File

FAQ

What are the key clinical trial results for Dupixent in treating CSU (REGN)?

Two Phase 3 trials demonstrated Dupixent's effectiveness in reducing itch severity and urticaria activity compared to placebo at 24 weeks, with positive results in both Study A (136 patients) and Study C (148 patients).

How many patients could benefit from Dupixent's CSU approval (REGN)?

Over 300,000 adults and adolescents aged 12 years and older in the U.S. with CSU who remain symptomatic despite antihistamine treatment could benefit from this approval.

What is the safety profile of Dupixent for CSU treatment (REGN)?

The safety profile was consistent with known Dupixent results, with injection site reactions being the most common adverse event (≥2%) compared to placebo.

In which countries is Dupixent already approved for CSU treatment (REGN)?

Dupixent is currently approved for CSU treatment in Japan, the United Arab Emirates (UAE), and Brazil, with additional regulatory reviews ongoing worldwide.