FDA Approves First Treatment for Allergic Fungal Rhinosinusitis

The FDA has approved dupilumab (Dupixent) for the treatment of allergic fungal rhinosinusitis (AFRS), marking the first approved therapy for this condition.

The approval applies to adults and children aged 6 years and older who have previously undergone sino-nasal surgery, reflecting the high risk of disease recurrence after surgical treatment alone.

This decision represents an important advancement in managing AFRS, a condition historically limited to surgery and supportive medical therapies.

Condition

Allergic fungal rhinosinusitis (AFRS) is an uncommon type of chronic sinus inflammation caused by an allergic reaction to fungi growing in the sinuses, with production of thick, sticky mucus often described as resembling peanut butter. AFRS affects up to 8% of people with chronic sinus inflammation and nasal polyps, is more common in warm, humid areas where fungi thrive, and typically begins in teenagers and young adults. If left untreated, AFRS can cause serious problems, including expansion of the sinuses, erosion of surrounding bone (in up to 90% of patients), and spread to the eye area or brain, leading to facial deformities, vision problems, and nerve damage.

Data Supporting Dupixent

Dupilumab's effectiveness and safety were evaluated in a 52-week study of adult and pediatric participants aged 6 years and older with AFRS. The study showed that dupilumab significantly improved sinus opacification compared to placebo, as measured by CT scan scores (Lund-Mackay score). Additional measures — including nasal polyp size, nasal congestion, and sense of smell — also showed significant improvement and supported the main findings.

Dupilumab substantially reduced the need for systemic corticosteroids and sinus surgery compared to placebo over 52 weeks, which is particularly important given the severity of AFRS. The medication also reduced sinus bone erosion, a serious complication unique to AFRS. Together, these results demonstrate clear benefits across imaging findings, endoscopic results, and patient-reported symptoms.

The safety profile of dupilumab in AFRS patients is similar to what has been observed in patients with chronic rhinosinusitis with nasal polyps, both in clinical trials and post-market setting. No safety issues were identified that would outweigh the benefits of dupilumab.

For children and adolescents aged 6 to <18 years, the effectiveness of dupilumab is based on adult AFRS data, supported by the fact that the disease works similarly across age groups and that children achieve comparable drug levels at weight-adjusted doses. Safety data comes from supportive results in children and adolescents treated for other conditions.

Based on the trial results and the existing safety database for dupilumab's approved uses, the benefits outweigh the risks for treating AFRS in patients 6 years and older.

Safety Information

The most common side effects of Dupixent are injection-site reactions, eosinophilia (elevated count of white blood cells), insomnia, toothache, gastritis, and joint pain.

Designation

Dupixent received priority review designation for this indication.