How to appeal a Dupixent denial

Dupixent (dupilumab) was first approved in March 2017 for eczema (atopic dermatitis). As of November 2026, its label lists these uses:

• Moderate-to-severe atopic dermatitis, age 6 months and older.
• Moderate-to-severe eosinophilic or steroid-dependent asthma, age 6 and older.
• Chronic rhinosinusitis with nasal polyps, age 12 and older.
• Eosinophilic esophagitis, age 1 and older and at least 15 kg.
• Prurigo nodularis in adults.
• COPD with an eosinophilic phenotype in adults, approved September 2024.
• Chronic spontaneous urticaria (hives) despite antihistamines, approved April 2025 and extended to children 2 and older in April 2026.
• Bullous pemphigoid in adults, approved June 2025.
• Allergic fungal rhinosinusitis after sinus surgery, age 6 and older, approved February 2026.

If your condition is not on this list, the plan may call the request off-label or experimental. See experimental denials.

Each plan writes its own prior-authorization criteria. For eczema, the label itself covers disease not adequately controlled with topical prescription therapies. One insurer's national policy, reviewed April 2026, turns that into specific rules for a first approval:

• Eczema on at least 10 percent of the body, or moderate-to-severe hand or foot eczema for age 12 and up.
• A prescription topical steroid used daily for at least 28 days without enough improvement.
• A prescription from, or in consultation with, an allergist, immunologist or dermatologist.

For asthma, the same policy asks for a blood eosinophil count of at least 150 or steroid-dependent asthma, plus three months of an inhaled steroid and another controller.

Approvals can be time-limited. Under that policy, renewal requires that the patient has responded to therapy, so follow-up notes should describe the improvement.

Job-based plans must cite the specific plan provision behind a denial and give you a free copy of any criteria they used if you ask. Ask for it. Compare each line to your records.

• "Criteria not met" or "step therapy" means the plan wants proof of severity or prior treatment. See step therapy denials.
• "Not medically necessary" is a medical-judgment denial that can go to external review. See medical necessity denials.
• "Non-formulary" means the plan prefers another drug; ask for an exception.
• "Experimental" or "off-label" for a condition that appears on the FDA label is worth challenging. Attach the label page that lists your condition.

Ask your doctor for a letter that walks through your history against the plan's criteria. It helps when it includes:

• The diagnosis and how severe it is, with measures the plan asks for, such as body surface area for eczema or dated eosinophil counts for asthma.
• Every prior treatment: drug name, strength, dates, how long you used it, and what happened.
• Side effects or reasons a treatment was not safe for you.
• The specialist's role in your care.
• For renewals, specific signs of improvement since starting Dupixent.

This mirrors what exception rules ask doctors to show: that covered drugs have not worked or will not work as well, or are likely to cause harm. Pharmacy records and old prescriptions help prove the dates.

Send the letter with a copy of the denial, the plan's criteria, recent visit notes, and any test results the criteria mention. Number each criterion in the letter and point to the page of your records that meets it, so the reviewer does not have to search.

File the internal appeal within 180 days of the denial. If you are already on Dupixent and coverage lapses, say so: being in the middle of a course of treatment on a non-formulary drug qualifies for an expedited exception in individual and small-group plans. Those plans must decide a formulary exception within 72 hours, or 24 hours when you are mid-treatment, and a denial can go to an independent reviewer.

With a Medicare drug plan, an exception request needs a statement from your prescriber; the plan must decide within 72 hours, or 24 hours if expedited, and you have 65 days to appeal. Part D exceptions can also address step therapy and dose limits. See Part D appeals.

If a private plan upholds a medical-necessity denial, you can ask for external review within 4 months of the final decision. Your insurer has to accept the reviewer's decision.

The manufacturers run DUPIXENT MyWay, which offers help understanding insurance coverage and financial assistance options.