FDA Prioritizes Review of Dupixent sBLA for Bullous Pemphigoid Treatment

On February 18, 2025, the U.S. Food and Drug Administration (FDA) accepted the supplemental biologics license application (sBLA) for Dupixent (dupilumab) for priority review. This application is for the treatment of adults with bullous pemphigoid (BP), a chronic and debilitating skin condition characterized by severe itchiness, blisters, and painful skin lesions primarily affecting the elderly. If approved, Dupixent would be the first targeted treatment for BP in the United States, with an FDA decision expected by June 20, 2025.

BP is a condition marked by underlying type 2 inflammation, leading to intense itching, blisters, red patches, and painful sores on the skin. This disease frequently causes the skin to bleed and form crusts, increasing the risk of infections and significantly affecting daily life. In the U.S., approximately 27,000 adults suffer from BP that cannot be adequately controlled with systemic corticosteroids.

The sBLA submission for Dupixent is grounded in data from a pivotal clinical study that evaluated the drug's efficacy and safety in 106 adults with moderate-to-severe BP. The study achieved its primary endpoint, revealing that patients treated with Dupixent were five times more likely to achieve sustained disease remission compared to those on a placebo. Sustained remission was defined as complete clinical remission following the tapering off of oral corticosteroids (OCS) by week 16 and relying solely on Dupixent for at least 20 weeks without relapse. Over the 36-week treatment period, Dupixent demonstrated notable reductions in disease severity, itching, and reliance on OCS compared to placebo.

While Dupixent showed significant benefits, it also presented some adverse effects. Observed side effects occurring more frequently in the Dupixent group than in the placebo group included peripheral edema, joint pain, back pain, blurred vision, high blood pressure, asthma, conjunctivitis, constipation, upper respiratory infections, limb injuries, and insomnia.

Dupixent's priority review status is a recognition by the FDA of the potential for significant advancements in treating serious conditions. This status can expedite the review process for therapies showing promise in improving treatment, diagnosing, or preventing life-threatening diseases. Additionally, Dupixent has received orphan drug designation from the FDA, a status granted to investigational treatments for rare conditions affecting fewer than 200,000 people in the United States.

Dupixent, a fully human monoclonal antibody, works by inhibiting the signaling of the interleukin-4 (IL4) and interleukin-13 (IL13) pathways, key drivers of type 2 inflammation. It is not an immunosuppressant. The Dupixent development program has shown substantial clinical benefits and reduced type 2 inflammation in phase 3 studies, establishing its importance for conditions related to type 2 inflammation.

Globally, Dupixent has received regulatory approvals in over 60 countries for various indications, including atopic dermatitis, asthma, chronic rhinosinusitis with nasal polyps, eosinophilic esophagitis, prurigo nodularis, chronic spontaneous urticaria, and chronic obstructive pulmonary disease. Over one million patients worldwide are currently being treated with Dupixent.

The development of Dupilumab is a collaborative effort between Sanofi and Regeneron. It has been studied in over 60 clinical trials involving more than 10,000 patients with chronic diseases partly driven by type 2 inflammation. Research continues on other potential uses of Dupilumab, including chronic pruritus of unknown origin and lichen simplex chronicus, though these applications are still under investigation.