Srt Fabry Galafold denied as duplicate or overlapping therapy by Aetna?

Aetna's specific coverage criteria for srt fabry galafold 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 May Deny Galafold (Migalastat) for Fabry Disease as Duplicate Therapy

Aetna's duplicate-therapy denial for migalastat (Galafold) in Fabry disease means a clinical reviewer concluded that the patient is already receiving another treatment that serves the same therapeutic purpose — most commonly enzyme replacement therapy (ERT). However, migalastat and ERT are not interchangeable for all patients: migalastat is an oral pharmacological chaperone approved only for patients whose Fabry disease is caused by a specific subset of amenable GLA gene variants, whereas ERT is a biweekly intravenous infusion suitable for a broader mutation profile. A patient who is currently on ERT and transitioning to migalastat — or who is being considered for migalastat as an alternative — may receive a duplicate-therapy denial if the clinical record does not clearly document the rationale for the transition and the mutation-amenability basis for migalastat.

This denial is appealable because the two treatment modalities have distinct mechanisms, distinct patient-eligibility profiles, and distinct routes of administration.

## Federal Appeal Framework

• Internal appeal (ACA §2719 / ERISA §503): File within the deadline on your EOB. Aetna must respond within 30 days (prospective) or 60 days (post-service).
• External review: If the internal appeal is denied, IRO review is available, generally within four months of the final adverse internal determination. An independent clinical reviewer with rare-disease expertise can assess whether the duplicate-therapy characterization is clinically accurate.
• Expedited track: Available (72 hours) where delay would cause serious health harm.

## Documentation to Gather

1. GLA mutation amenability documentation: The single most important document. Obtain the patient's confirmed GLA gene variant from the diagnostic report and confirm — using the FDA-approved prescribing label's amenability criteria or the manufacturer's amenability tool — that the variant is listed as amenable. This directly distinguishes migalastat from ERT at the biological level. 2. Transition rationale letter: If transitioning from ERT to migalastat, the treating physician's letter should explain the clinical basis for the transition — including the confirmed amenable mutation, the clinical appropriateness of the switch, and why continued ERT alongside migalastat is not the plan. 3. Diagnosis and variant confirmation: Genetic testing report confirming Fabry disease diagnosis and the specific GLA variant. 4. Current medication list with clinical context: If the concern is simultaneous use, document that the plan is to transition, not to use both therapies concurrently. 5. Applicable guideline reference: Reference relevant guidance from organizations such as the applicable rare-disease or metabolic-disorder specialist society generically.

## Criteria-Mapping Structure

Obtain Aetna's current medical policy for migalastat and the FDA-approved prescribing label. For each duplicate-therapy criterion cited in the denial, provide the specific chart or genetic test evidence that addresses it. Lead the appeal with the mutation amenability data — this is the clinical fact that most directly refutes a duplicate-therapy characterization.