Medicare will cover Biogen’s Alzheimer’s treatment Aduhelm only during clinical trials, the Centers for Medicare and Medicaid Services announced Thursday, completing a proposal in January.

Medicare beneficiaries participating in clinical trials overseen by CMS, the Food and Drug Administration, or the National Institutes of Health are eligible for Aduhelm coverage new policy. Previous versions limited drug reimbursement to patients in CMS or NIH-approved studies.

CMS said the limited Aduhelm coverage decision will not automatically extend to new Alzheimer’s drugs as long as they undergo a full review by the FDA, rather than the accelerated process the regulator uses to approve Biogen treatments.

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