The U.S. Food and Drug Administration (FDA) has accepted Sanofi and Regeneron's supplemental biologics license application (sBLA) for Dupixent (dupilumab) with priority review status for the treatment of adults with bullous pemphigoid (BP). If approved, Dupixent would become the first targeted therapy available for BP patients in the United States, with an FDA decision anticipated by June 20, 2025.
Promising Clinical Trial Results
The application is supported by compelling data from a pivotal study involving 106 adults with moderate-to-severe BP. The trial demonstrated remarkable efficacy, with Dupixent patients achieving sustained disease remission at five times the rate of those receiving placebo. Sustained remission was defined as complete clinical improvement with successful completion of oral corticosteroid (OCS) tapering by week 16, maintaining remission without relapse or rescue therapy throughout the 36-week treatment period.
Key secondary endpoints also showed significant improvements, with Dupixent effectively reducing disease severity, itch intensity, and the need for oral corticosteroids compared to placebo treatment.
Safety Profile and Observed Effects
The safety assessment revealed several adverse events occurring more frequently in the Dupixent group compared to placebo. These included peripheral edema, arthralgia, back pain, blurred vision, hypertension, and various other conditions, though each affected a small number of patients (at least 3 per condition).
Understanding Bullous Pemphigoid
Bullous pemphigoid represents a significant burden for affected individuals, particularly in the elderly population. This chronic autoimmune skin condition is characterized by:
- Intense itching
- Formation of blisters and rashes
- Skin redness and painful lesions
- Increased susceptibility to infections
- Impact on daily functioning
Currently, approximately 27,000 adults in the United States live with BP that remains uncontrolled despite treatment with systemic corticosteroids, highlighting the urgent need for new therapeutic options.
Mechanism of Action and Regulatory Status
Dupixent functions as a fully human monoclonal antibody that targets the IL-4 and IL-13 pathways, key drivers of type 2 inflammation, without acting as an immunosuppressant. The FDA's priority review designation acknowledges the potential significant improvements this therapy could bring to BP treatment.
The drug previously received orphan drug designation for BP, a status granted to promising treatments for rare diseases affecting fewer than 200,000 people in the United States. While Dupixent has already secured regulatory approvals in over 60 countries for various other inflammatory conditions, its safety and efficacy specifically for BP remain under clinical assessment.
