Dupixent® (dupilumab) Approved in the U.S. as the Only Targeted Medicine to Treat Patients with Bullous Pemphigoid (BP)

Rhea-AI Summary

The FDA has approved Dupixent (dupilumab) as the first targeted treatment for adults with bullous pemphigoid (BP), a rare skin disease affecting approximately 27,000 U.S. adults. The approval is based on the ADEPT Phase 2/3 trial results, where Dupixent showed significant improvements compared to placebo: 18.3% of patients achieved sustained disease remission vs 6.1%, 38.3% experienced meaningful itch reduction vs 10.5%, and patients required lower oral corticosteroid doses (2.8g vs 4.1g). BP primarily affects elderly patients, causing intense itching, painful blisters, and skin lesions. Dupixent is now approved for eight distinct diseases with type 2 inflammation, spanning skin, gut, and respiratory conditions. The FDA granted Priority Review and Orphan Drug Designation for this indication.

Positive

• First FDA-approved targeted treatment for bullous pemphigoid, addressing an unmet medical need
• Demonstrated 18.3% sustained disease remission rate compared to 6.1% for placebo
• Achieved 38.3% clinically meaningful itch reduction vs 10.5% for placebo
• Reduced median cumulative oral corticosteroid use (2.8g vs 4.1g)
• Expands Dupixent's approved indications to eight distinct diseases

Negative

• Limited efficacy with only 18.3% of patients achieving sustained disease remission
• Several adverse events reported including arthralgia, conjunctivitis, blurred vision, and viral infections
• One case of acute generalized exanthematous pustulosis reported in Dupixent group

Insights

Pharmaceutical Industry Analyst

FDA approval of Dupixent for bullous pemphigoid expands Regeneron's market, addressing unmet needs in a rare disease affecting 27,000 U.S. patients.

The FDA approval of Dupixent for bullous pemphigoid (BP) represents a significant expansion of Regeneron and Sanofi's blockbuster drug into its eighth distinct indication. This approval is particularly notable as Dupixent becomes the first and only targeted therapy for this rare autoimmune skin disease affecting approximately 27,000 adults in the U.S.

The market opportunity, while modest compared to Dupixent's larger indications like atopic dermatitis and asthma, is commercially meaningful given the complete lack of targeted competition and the drug's premium pricing. BP primarily affects elderly patients who have limited treatment options, typically relying on oral corticosteroids that carry significant side effects, especially problematic in older populations.

The pivotal data shows Dupixent achieved 18.3% sustained disease remission versus 6.1% for placebo, with 38.3% of patients experiencing meaningful itch reduction compared to 10.5% on placebo. Importantly, patients required less corticosteroid use (2.8g cumulative dose versus 4.1g), addressing a critical need in this elderly population.

This approval further strengthens Dupixent's position as Regeneron's flagship revenue driver and reinforces the drug's versatility across multiple type 2 inflammatory diseases. The Priority Review and Orphan Drug Designation highlight the FDA's recognition of the unmet need. The safety profile remained consistent with previous indications, critical for regulatory and commercial success in this eighth indication.

With additional regulatory applications under review globally (EU, Japan, China), this approval represents just the first step in a potential worldwide expansion for this indication, further extending Dupixent's commercial runway and reinforcing Regeneron's dominance in targeting type 2 inflammation.

Approval based on pivotal results showing improvements in sustained disease remission and reductions in itch and oral corticosteroid use compared to placebo in adults with BP

BP is a chronic, debilitating and relapsing rare skin disease affecting approximately 27,000 adults in the U.S. whose disease is uncontrolled by systemic corticosteroids

Dupixent is now approved in the U.S. to treat eight distinct diseases with underlying type 2 inflammation, including diseases of the skin, gut, and respiratory system that affect a broad range of patients, from infants to elderly people

TARRYTOWN, N.Y. and PARIS, June 20, 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 adult patients with bullous pemphigoid (BP).

BP primarily affects elderly patients, and is characterized by intense itch, painful blisters and lesions, as well as reddening of the skin. It can be chronic and relapsing with underlying type 2 inflammation. The blisters and rash can form over much of the body and cause the skin to bleed and break down, resulting in patients being more prone to infection and affecting their daily functioning. Available treatment options are limited and can add to overall disease burden by suppressing a patient’s immune system.

“People affected by bullous pemphigoid endure unrelenting itch and painful blisters that can damage the skin. Until now, these primarily elderly patients have had limited therapeutic options available, with potential side effects that have often added to their burden,” Patrick Dunn, Executive Director at the International Pemphigus and Pemphigoid Foundation. “The approval of Dupixent for bullous pemphigoid brings a novel treatment approach to patients and their caregivers, and we are grateful for the tireless efforts of the scientific community who helped us reach this critical milestone.”

“Today’s approval extends the remarkable ability of Dupixent to transform treatment paradigms for people living with a variety of diseases with underlying type 2 inflammation, from common conditions like asthma and atopic dermatitis, to rarer ones such as eosinophilic esophagitis and prurigo nodularis, and now including bullous pemphigoid,” said George D. Yancopoulos, M.D., Ph.D., Board co-Chair, President and Chief Scientific Officer at Regeneron, and a principal inventor of Dupixent. “Dupixent has shown the potential to improve the most challenging effects of bullous pemphigoid, while helping some patients achieve sustained disease remission and decreased oral corticosteroid use. Additionally, this approval further reinforces the demonstrated safety profile of Dupixent in a broad age range of patients, from infants to elderly people, and across dermatological, respiratory and gastrointestinal diseases.”

The FDA approval is based on data from the pivotal ADEPT Phase 2/3 trial that evaluated the efficacy and safety of Dupixent compared to placebo in adults with moderate-to-severe BP. Patients were randomized to receive Dupixent 300 mg (n=53) or placebo (n=53) added to standard-of-care oral corticosteroids (OCS). During treatment, all patients underwent a protocol-defined OCS tapering regimen if control of disease activity was maintained. During the FDA review, the analyses were updated; the FDA-approved results at 36 weeks in the label for Dupixent compared to placebo are:

• 18.3% of patients experienced sustained disease remission compared to 6.1% (12.2% difference; 95% confidence interval: -0.8% to 26.1%), the primary endpoint
• 38.3% of patients achieved clinically meaningful itch reduction compared to 10.5%
• Median cumulative OCS dose was 2.8 grams compared to 4.1 grams
  

In this elderly population, the most common adverse events (≥2%) more frequently observed in patients on Dupixent compared to placebo were arthralgia, conjunctivitis, blurred vision, herpes viral infections and keratitis. Additionally, 1 case of acute generalized exanthematous pustulosis was reported in 1 patient treated with Dupixent and 0 patients treated with placebo.

“Until now, treating bullous pemphigoid was very challenging for elderly patients struggling with the debilitating impact of blisters and lesions, and potentially co-morbid conditions,” said Alyssa Johnsen, M.D., Ph.D., Global Therapeutic Area Head, Immunology and Oncology Development at Sanofi. “By addressing two central drivers of the underlying type 2 inflammation that contributes to bullous pemphigoid, Dupixent is the first targeted medicine to allow patients the potential to achieve sustained remission and reduce itch. This approval in the U.S. is important for the thousands of patients living with bullous pemphigoid, and we look forward to working with regulators around the world to bring this innovative medicine to more patients in need.”

The FDA evaluated Dupixent under Priority Review, which is reserved for medicines that represent potentially significant improvements in efficacy or safety in treating serious conditions. Dupixent was previously granted Orphan Drug Designation by the FDA for BP, which applies to investigational medicines intended for the treatment of rare diseases that affect fewer than 200,000 people in the U.S. Additional regulatory applications are also under review around the world, including in the EU, Japan and China.

About the Dupixent BP Pivotal Trial
ADEPT was a randomized, Phase 2/3, double-blind, placebo-controlled trial evaluating the efficacy and safety of Dupixent in 106 adults with moderate-to-severe BP for a 52-week treatment period. After randomization, patients received Dupixent or placebo every two weeks after an initial loading dose, along with OCS treatment. During treatment, OCS taper was initiated after patients experienced two weeks of sustained control of disease activity. OCS tapering could start between four to six weeks after randomization and was continued if disease control was maintained, with the intent of completion by 16 weeks. After OCS tapering, patients were only treated with Dupixent or placebo for at least 20 weeks (rescue treatment could be used if required).

The primary endpoint evaluated the proportion of patients achieving sustained disease remission at 36 weeks. Sustained disease remission was defined as complete clinical remission with completion of OCS taper by 16 weeks without relapse after completion of the OCS taper and no rescue therapy use during the 36-week treatment period. Relapse was defined as appearance of ≥3 new lesions a month or ≥1 large lesion or urticarial plaque (>10 cm in diameter) that did not heal within a week. Rescue therapy could include treatment with high-potency topical corticosteroids, OCS (including increase of OCS dose during the taper or re-initiation of OCS after completion of the OCS taper), or systemic non-steroidal immunosuppressive medications or immunomodulating biologics.

Select secondary endpoints evaluated at 36 weeks included:

• Proportion of patients with ≥4-point reduction in Peak Pruritus Numerical Rating Scale (PP-NRS; scale 0-10)
• Total cumulative OCS dose

About Dupixent
Dupixent is an injection administered under the skin (subcutaneous injection) at different injection sites. In adults with BP, Dupixent 300 mg is administered every other week after an initial loading dose, and in combination with a tapering course of oral corticosteroids. 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.

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, chronic spontaneous urticaria (CSU), chronic obstructive pulmonary disease (COPD) and BP 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 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 AD 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 CRSwNP 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 EoE 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 PN 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 COPD 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 CSU under 12 years of age, or who weigh less than 66 pounds (30 kg).
• to treat adults with bullous pemphigoid (BP). It is not known if DUPIXENT is safe and effective in children with BP under 18 years of age.

DUPIXENT is not used to relieve sudden breathing problems and will not replace an inhaled rescue medicine or 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 AD, CRSwNP, EoE, PN, COPD, CSU, or BP 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, including skin 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, skin rash, including rash that looks like a bullseye, painful red or blue bumps under the skin, or red pus-filled spots on the skin, general ill feeling, itching, swollen lymph nodes, nausea or vomiting, joint pain, 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 get: 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 problems, including eye and eyelid inflammation, redness, swelling, itching, eye infection, dry eye, and blurred vision, 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 problems, including eye and eyelid inflammation, redness, swelling, itching, eye infection, and blurred vision, high count of a certain white blood cell (eosinophilia), stomach problems (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 problems, including eye and eyelid inflammation, redness, swelling, itching, and 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, stomach problems (gastritis), joint pain (arthralgia), toothache, headache, and urinary tract infection.
• Chronic Spontaneous Urticaria: injection site reactions.
• Bullous Pemphigoid: joint pain (arthralgia), eye problems, including eye and eyelid inflammation, redness, swelling, itching, and blurred vision, and herpes virus infections.

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 
Sanofi is an R&D driven, AI-powered biopharma company committed to improving people’s lives and delivering compelling growth. We apply our deep understanding of the immune system to invent medicines and vaccines that treat and protect millions of people around the world, with an innovative pipeline that could benefit millions more. Our team is guided by one purpose: we chase the miracles of science to improve people’s lives; this inspires us to drive progress and deliver positive impact for our people and the communities we serve, by addressing the most urgent healthcare, environmental, and societal challenges of our time.

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. 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¹ Data on File

FAQ

What is the FDA approval status of Dupixent (REGN) for bullous pemphigoid?

The FDA has approved Dupixent as the first and only targeted medicine for treating adult patients with bullous pemphigoid (BP) in June 2025.

What were the key efficacy results for Dupixent in the bullous pemphigoid trial?

In the ADEPT trial, 18.3% of Dupixent patients achieved sustained disease remission vs 6.1% for placebo, with 38.3% experiencing meaningful itch reduction vs 10.5% for placebo.

How many patients are affected by bullous pemphigoid in the United States?

Approximately 27,000 adults in the U.S. are affected by bullous pemphigoid whose disease is uncontrolled by systemic corticosteroids.

What are the main side effects of Dupixent for bullous pemphigoid treatment?

The most common side effects included arthralgia, conjunctivitis, blurred vision, herpes viral infections, and keratitis, with one case of acute generalized exanthematous pustulosis.

How many diseases is Dupixent now approved to treat in the US?

Dupixent is now approved to treat eight distinct diseases with underlying type 2 inflammation, including conditions affecting the skin, gut, and respiratory system.