Anti Amyloid Leqembi denied as non-formulary by Aetna?

Aetna's specific coverage criteria for anti amyloid leqembi are defined in its own published medical/coverage policy and the FDA-approved prescribing label. A successful appeal documents that your medical records satisfy each criterion those sources list — confirmed diagnosis, any required prior treatments (with dates and outcomes), and clinical severity. If the exact criteria weren't included with your denial, request them in writing; your appeal then maps each requirement to the matching fact in your chart.

## Why Aetna Denied Leqembi as Non-Formulary — and Your Path to Coverage

A non-formulary denial means Leqembi (lecanemab) is either not included on Aetna's approved drug list for your specific plan or is placed on a tier that requires additional approval. Non-formulary denials are common for newer specialty biologics and do not mean the drug is unsafe, inappropriate, or unavailable — they mean you need to use the formulary exception process to obtain coverage.

## Why This Denial Happens

Formularies are updated on annual cycles. Leqembi, as a relatively recently approved anti-amyloid therapy, may not yet be included in every Aetna plan's formulary, or may be listed with a non-preferred designation that triggers prior authorization or cost-sharing requirements. Aetna is required by ACA and ERISA to have a formulary exception process, and that process is specifically designed for situations where no formulary alternative is clinically appropriate.

## Federal Appeal Rights

• Formulary exception request: Before or alongside a formal appeal, submit a formulary exception request with supporting clinical documentation. If Aetna denies the exception, that denial itself triggers full appeal rights.
• Internal appeal (ACA §2719 / ERISA §503): File a written appeal within the timeframe on your denial notice. The full-and-fair review standard requires clinical review, not just formulary-category comparison.
• Expedited appeal: Available if your neurologist certifies urgency; Aetna must respond within 72 hours.
• External review: After final internal denial, you have approximately four months to request independent external review. Non-formulary denials are overturned by IROs when the record shows no formulary alternative is clinically equivalent to the requested drug.

## Documentation to Gather

1. Diagnosis and eligibility records — Clinical notes confirming early symptomatic Alzheimer's disease with amyloid confirmation consistent with Leqembi's FDA-approved indication. 2. No-equivalent-alternative letter — Ask the prescribing neurologist to write a letter stating that no drug currently on Aetna's formulary is a clinically equivalent substitute for Leqembi, with a brief explanation of the mechanistic distinction. 3. FDA prescribing label — The current label confirming the approved indication and mechanism of action. 4. Aetna's formulary and exception policy — Request the formulary tier listing for your plan and Aetna's written formulary exception criteria. 5. Prescriber medical-necessity letter — A letter documenting medical necessity and explaining why formulary alternatives (if any exist) are not appropriate for this patient.

## Criteria-Mapping Structure for Your Exception/Appeal

| Aetna Exception Criterion | Your Response | Evidence | |---|---|---| | No formulary alternative is clinically equivalent | Leqembi's mechanism is distinct | Neurologist letter + FDA label comparison | | Drug is medically necessary for this patient | Confirmed diagnosis + clinical profile | Specialist notes + amyloid confirmation | | Patient meets FDA-approved indication | Early symptomatic AD + amyloid confirmed | Diagnosis records + imaging/CSF report |

If Aetna's denial letter lists a specific formulary alternative it considers equivalent, your appeal must directly address why that drug is not interchangeable — mechanistically and clinically — with Leqembi for this patient.