Sanofi and Regeneron's Dupixent Gains FDA Approval for Chronic Spontaneous Urticaria, Marking Its Seventh Indication

The U.S. Food and Drug Administration (FDA) has approved Dupixent (dupilumab) for the treatment of chronic spontaneous urticaria (CSU) in patients aged 12 and older who remain symptomatic despite antihistamine use. This latest approval marks the seventh indication for the blockbuster drug, jointly developed by Sanofi and Regeneron Pharmaceuticals.

Breakthrough in Chronic Hives Treatment

Dupixent is now the first new targeted treatment for CSU in over a decade, offering hope to an estimated 300,000 patients in the United States who struggle with persistent symptoms despite current standard-of-care treatments. The approval comes after an initial setback in 2023 when the FDA rejected the drug for this indication, requesting additional efficacy data.

Dr. George Yancopoulos, Chief Scientific Officer at Regeneron, highlighted the significance of this approval, stating, "Dupixent is the first new targeted treatment for chronic spontaneous urticaria, or CSU, in over ten years, with pivotal trials demonstrating its ability to help patients significantly reduce the hallmark symptoms of intense itch and unpredictable hives associated with this disease."

Clinical Trial Success and FDA Approval

The FDA's decision was based on positive results from the Liberty-Cupid Study C, which enrolled patients with uncontrolled symptoms who were already taking antihistamines. The trial showed that patients who added Dupixent to their regimen experienced an almost 50% reduction in itch and urticaria activity scores compared to those given a placebo.

Key findings from the Liberty-Cupid C trial include:

• A reduction of 8.6 points in itch severity (on a scale of 21) for Dupixent-treated patients, compared to a 6.1-point reduction for patients on placebo plus standard-of-care (SOC) antihistamines
• A 15.9-point reduction in itch and hive severity (on a 42-point scale) for the Dupixent group versus an 11.2-point reduction for the control group
• 30% of Dupixent-treated patients experienced a complete response, compared with 18% of those on placebo

Market Implications and Competition

Dupixent, which generated nearly $14 billion in sales last year, now faces both opportunities and challenges in the CSU market. While the approval opens up a new patient population for the drug, some analysts remain skeptical about its commercial potential in this indication.

Analysts at Cantor Fitzgerald have described Dupixent's results in urticaria as "underwhelming" compared to data generated by competitors such as Celldex Therapeutics. Additionally, the investment bank Jefferies reported that dermatologists view the drug as a "non-factor" compared to other emerging agents for the condition.

The CSU market is becoming increasingly competitive, with several pharmaceutical companies advancing new therapies. Novartis, which markets Xolair (omalizumab) - the only other biologic approved for CSU - is developing remibrutinib, an oral BTK inhibitor that has shown promise in two phase 3 trials. With Xolair facing upcoming biosimilar competition, the landscape for CSU treatment is likely to evolve rapidly in the coming years.