Regeneron Pharmaceuticals, Inc. and Sanofi announced a pivotal Phase 3 trial evaluating Dupixent® (dupilumab) in patients with moderate-to-severe chronic spontaneous urticaria (CSU) met its primary and all key secondary endpoints at 24 weeks. Adding Dupixent to standard-of-care antihistamines significantly reduced itch and hives for biologic-naïve patients, compared to antihistamines alone in Study A, the first of two trials of the LIBERTY-CUPID clinical program. CSU is a chronic inflammatory skin disease characterized by the sudden onset of hives on the skin and/or swelling deep under the skin.

Despite standard-of-care treatment, people with CSU often experience symptoms including a persistent itch or burning sensation, which can be debilitating and significantly impact quality of life. Swelling often occurs on the face, hands and feet, and can also affect the throat and upper airways. CSU is typically treated with antihistamines but the disease remains uncontrolled for up to 50% of patients who have limited available treatment options.

CSU is the fifth disease for which Dupixent has positive Phase 3 data including atopic dermatitis, asthma, chronic rhinosinusitis with nasal polyposis and eosinophilic esophagitis (EoE, investigational). In the trial (n=138), adding Dupixent to standard-of-care antihistamines nearly doubled the reduction in itch and urticaria activity compared to standard-of-care alone (placebo) with continuous improvement out to 24 weeks. Patients experienced a: 63% reduction in itch severity with Dupixent versus 35% with placebo, as measured by a 0-21 point itch severity scale (10.24 point reduction with Dupixent versus 6.01 point reduction with placebo, p<0.001), the primary endpoint in the U.S. (secondary endpoint in the EU).

65% reduction in urticaria activity (itch and hive) severity with Dupixent versus 37% with placebo, as measured by a 0-42 point urticaria activity scale (20.53 point reduction with Dupixent versus 12.00 point reduction with placebo, p<0.001), the primary endpoint in EU (secondary endpoint in the U.S.). The trial demonstrated safety results similar to the known safety profile of Dupixent in its approved indications. For the 24-week treatment period, the occurrence of treatment emergent adverse events were generally similar between the Dupixent and placebo groups (50% Dupixent, 59% placebo).

The most common adverse events were injection site reactions (11% Dupixent, 13% placebo). The potential use of Dupixent in CSU and EoE is currently under clinical development, and the safety and efficacy have not been fully evaluated by any regulatory authority.