The U.S. Food and Drug Administration (FDA) has officially approved Dupixent (dupilumab) for the treatment of chronic spontaneous urticaria (CSU) in patients aged 12 years and older who did not receive relief with H1 antihistamine therapy. Â
CSU is a persistent skin condition characterized by sudden itchy hives because of type 2 inflammatory reactions. Many patients do not achieve adequate relief with H1 antihistamine treatment for chronic spontaneous urticaria. Disruptive symptoms persist after H1 antihistamine treatment, which has continued adverse effects on their everyday lives.
The U.S. health sector includes approximately 300,000 patients with chronic sores who underwent antihistamine therapy that did not provide sufficient relief. Kenneth Mendez, president and CEO of the Asthma and Allergy Foundation of America, explained the following: People who have CSU experience serious and rapid hives together with intense itching, which negatively impacts their day-to-day operations.
This new approval expands treatment possibilities, which brings hope for improved control to affected patients. Dr. Alyssa Johnsen, Global Head of Immunology and Oncology at Sanofi, stated that the approval “introduces a novel approach by targeting the underlying cause of uncontrolled CSU.” The approval has now introduced a novel method to treat symptoms since it attacks the source.
The FDA’s decision is based on results from three Phase 3 studies:
Study A enrolled 136 individuals, and Study C included 148 individuals aged 12 and older who had persistent symptoms after use of antihistamines and following their resistance to biologic treatments. Clinical trials assessing Dupixent as an additional treatment found that the medication proved more effective than placebo for reducing hives and decreasing severe itchiness over 24 weeks. The rates of disease control showed that Dupixent patients experienced either complete symptom clearance or improved disease management. Study B investigated 108 patients who were unresponsive to or ineligible for anti-IgE therapies. In addition to safety evaluation, Dupixent proved effective in symptom amelioration.
All three research studies were designed to determine patient itch level alterations between baseline and week 24 measurements using the weekly itch severity score (0 to 21). At week 24, researchers assessed the key secondary goals by measuring both hive and itch changes using the UAS7 score, which ranges from 0 to 42. The secondary outcome measured patient disease control by assessing patients who achieved UAS7 levels of 6 or less, alongside complete response detection, as UAS7 equals zero at week 24.
Studies have shown that the side effects of Dupixent treatment match the previously documented effects of this medication. Injection site reactions were reported in at least 2% of patients, consistent with previously known side effects of Dupixent. Regeneron President Dr. George D. Yancopoulus expressed these views about Dupixent. Dupixent represents the first newly approved targeted treatment for CSU in over ten years. Research shows Dupixent effectively decreases hives combined with itch while possibly demonstrating benefits for people dealing with eczema or asthma and similar conditions. The company looks forward to providing this treatment as an option to the more than 300,000 U.S. patients who lacked effective treatments until now. Dupixent has already been approved for CSU in Japan, the United Arab Emirates, and Brazil, and is currently under regulatory review in several other countries, including in the EU.
Dupixent is administered as a subcutaneous injection. Adult patients with chronic spontaneous urticaria receive a 300 mg dosage administered every two weeks after receiving the initial loading dose. The treatment amount of Dupixent for patients between 12 and 17 years of age depends on their body weight. Patients who weigh between 30 kg and 60 kg take 200 mg every two weeks, but those who weigh more than 60 kg take 300 mg during the same period. The medication can be administered in a clinical setting or at home after appropriate training by a healthcare provider. Administering the treatment to teens requires adult oversight during the process.
Dupixent is a fully human monoclonal antibody that prevents IL-4 and IL-13 signals from reaching their targets, key drivers of type 2 inflammation. It is not classified as an immunosuppressant. Phase 3 studies within the Dupixent development program revealed important clinical outcomes because they showed a reduction in type 2 inflammatory processes. Research evidence reveals that IL-4 and IL-13 function as fundamental elements in initiating type 2 inflammation that maintains various linked diseases concurrently.
References: Sanofi. Press Release: Dupixent approved in the US as the first new targeted therapy in over a decade for chronic spontaneous urticaria. Published April 18, 2025. Accessed April 22, 2025. Press Release: Dupixent approved in the US as the first new targeted therapy in over a decade for chronic spontaneous urticaria
