Aduhelm Insurance Denied? Appealing Aducanumab Coverage for Alzheimer's Disease

Aduhelm (aducanumab) became the first FDA-approved treatment for Alzheimer's disease with a disease-modifying mechanism when the FDA granted it accelerated approval in June 2021. The approval was controversial — the FDA's own advisory committee had voted against it — and was based on amyloid plaque reduction as a surrogate endpoint rather than demonstrated clinical benefit. Medicare's subsequent decision to limit coverage to clinical trial participants created one of the most restrictive coverage situations of any FDA-approved drug in recent memory. Biogen voluntarily discontinued Aduhelm's commercial availability in early 2024 following commercial failures, though patients enrolled in ongoing studies may still seek coverage.

This guide explains why Aduhelm denials occur and what options remain for patients who were being treated or who qualify under specific access programs.

Why Aduhelm Is Almost Universally Denied

CMS Coverage with Evidence Development (CED) restriction. Medicare's National Coverage Determination for anti-amyloid antibodies initially (under the original NCD) restricted coverage for Aduhelm specifically to patients enrolled in qualified clinical studies. This was an extraordinary restriction for an FDA-approved drug. The NCD was subsequently updated as Leqembi (lecanemab) received traditional approval, but Aduhelm's coverage situation remains highly restricted.

Accelerated approval without demonstrated clinical benefit. The FDA approved Aduhelm based on amyloid plaque reduction, a surrogate endpoint. The two pivotal trials showed inconsistent results — one demonstrated clinical benefit while the other did not. CMS used this clinical uncertainty as justification for its restrictive coverage policy.

Commercial insurer exclusions. Most commercial insurers followed Medicare's lead and either excluded Aduhelm from coverage or required enrollment in clinical trials or registries.

Biogen's commercial discontinuation. As of early 2024, Biogen discontinued the commercial marketing and sale of Aduhelm in the United States, redirecting resources to Leqembi. This means new patient access is essentially unavailable outside of continued access programs for existing patients or ongoing clinical research.

What Options Remain for Aduhelm Patients

If you were previously receiving Aduhelm and your coverage was denied or disrupted, the following arguments may still apply:

Continuity of care. If you were already receiving Aduhelm under a coverage arrangement that has been discontinued, you may be entitled to coverage continuity while transitioning to an alternative or completing a course of treatment. Document your prior treatment history and request bridge coverage.

Clinical trial enrollment. If you are enrolled in an ongoing clinical study involving Aduhelm or related anti-amyloid antibodies, your clinical trial costs may be covered under the ACA's clinical trial coverage provision (Section 2709), which requires plans to cover routine clinical care costs for participants in approved trials.

Transition to Leqembi. If you were being treated with Aduhelm, your neurologist may determine that transition to Leqembi — which now has traditional FDA approval and broader Medicare coverage — is clinically appropriate. A Leqembi appeal is likely to be more productive. See our separate guide on Leqembi insurance denials.

Building an Appeal for Existing Aduhelm Coverage

If you are an existing patient who received Aduhelm coverage and the insurer has now denied continuation:

Document treatment history and response. Provide records showing the duration of treatment, amyloid PET results before and after treatment, cognitive assessments during treatment, and clinical notes from your neurologist.

Cite continuity of care obligations. Many state insurance laws and plan documents contain continuity of care provisions protecting patients who are mid-course in an approved treatment.

Clinical trial participation documentation. If enrolled in a clinical study, provide the IRB-approved study protocol and ClinicalTrials.gov registration to support coverage of routine care costs under the ACA's clinical trial provision.

Neurologist letter. Your neurologist should document the clinical rationale for continued treatment, the patient's response to date, and the medical risks of discontinuation.

The Broader Lesson: CED and the Coverage Gap

Aduhelm's story illustrates a broader risk for patients with rare or controversial treatments: even FDA-approved drugs can face near-total coverage denial when the FDA's approval pathway is contested and CMS imposes Coverage with Evidence Development restrictions. If you are facing a similar situation with another therapy approved under accelerated approval with contested evidence, the arguments used in Aduhelm cases — clinical trial coverage rights, continuity of care, surrogate endpoint interpretation — may apply.

Expedited Review Rights

For any Aduhelm patient experiencing active cognitive decline and seeking continued access or transition coverage, document clinical urgency with your neurologist. Alzheimer's disease is progressive and irreversible, and delays in treatment decisions can have permanent consequences.

External Independent Review: Complete Guide" class="auto-link">External Review

External review remains available for Aduhelm denials. An independent neurologist reviewer can assess whether the insurer's denial criteria are clinically appropriate given the patient's specific situation, prior treatment, and response.

Patient Assistance

While Aduhelm is no longer commercially available, Biogen may maintain limited access programs for existing patients. Contact Biogen's patient support team for current options. For patients transitioning to Leqembi, Eisai and Biogen offer the Leqembi patient support program.

The Alzheimer's Association provides insurance advocacy resources. NORD may assist with emergency financial support.

Fight Back With ClaimBack

Even in a complex coverage environment, a denial is not automatically the final word. Whether you are seeking continued access, transition coverage, or clinical trial cost coverage, ClaimBack helps you build the strongest possible appeal.

Start your appeal at https://claimback.app/appeal.

Related Reading

• How to Write an Insurance Appeal Letter
• Internal vs. External Insurance Appeal: Which Should You File?
• Common Reasons Insurance Claims Are Denied