Q7 — Biogen's Aduhelm (aducanumab)

How did Aduhelm affect Medicare and its beneficiaries?

CMS projected a 15% rise in 2022 Part B premiums citing Aduhelm as the main reason — meaning 50 million beneficiaries paid more in anticipation of a drug very few would use, and mid-year corrections were legally impossible.

Julia Reyes/November 8, 2025
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Because Aduhelm is infused in clinics, it falls under Medicare Part B, which is partly funded by premiums paid by all beneficiaries. For 2022, CMS projected a 15% increase in Part B premiums and cited potential coverage of Aduhelm as the main reason. HHS Secretary Xavier Becerra ordered CMS to reassess the premium after the price cut, but legal and operational hurdles prevented mid-year changes, and the savings were rolled into 2023 premiums. In April 2022 Medicare finalised a narrow national coverage determination limiting payment to patients in qualifying clinical trials. The result was that the more than 50 million Americans who pay Part B premiums paid higher premiums in 2022 in anticipation of spending on a drug that very few would use.