Researchers: Ancillary Services Would Comprise 20% of Medicare Spending on Aduhelm

The policy that CMS proposed this week to restrict Medicare coverage of Aduhelm (aducanumab) to people enrolled in approved clinical trials would likely lead to fewer Alzheimer’s patients taking the drug and reduced Medicare expenditures.

Even so, the cost burden of Aduhelm worries payers. The discussion of the drug's cost has been almost exclusively on the price of the drug itself, which Biogen slashed in half late last year, from $56,000 to $28,200, in a bid to make the drug more palatable to payers. In November 2021, before Biogen announced the price cut, CMS announced a 14.5% increase in 2022 Medicare Part B premiums that was attributed, in part, to the added cost of covering Aduhelm.

John Mafi, M.D., M.P.H.

But a research team led by John Mafi, M.D., M.P.H., of UCLA argue in a research published in JAMA Health Forum yesterday that Aduhelm will result in spending on PET and MRI scans and other “ancillary” services beyond the cost of the drug itself. In their calculations, the cost of those ancillary services would comprise 20% of the total estimated Medicare Part B spending associated with Aduhelm.

Prior to the CMS proposal that might restrict coverage to those enrolled in sanctioned clinical trials, Mafi and his colleagues calculated that 1.1 million people might be eligible for Part B coverage of Aduhelm in a “lower bound” estimate that assumes prescribers would stick to the criteria used in clinical trial. Their “upper bound” estimate of eligibility was 5.7 million people.

Based on those estimates and a projection that just 25% of those eligible would receive Aduhelm, the researchers estimated that Medicare spending on Aduhelm could range from $7 billion per year, $1.4 billion of which would be for ancillary services, up to $37.4 billion, $7.5 billion would be for ancillary services.

Some of the ancillary services included in these calculations are PET scans ($2,300 per year per patient on average, counting patient coinsurance), routine MRIs ($555), APO E serum testing ($100 per patient), and hospitalization for adverse events ($294).

One of the important predicates for these calculations is that a large percentage (41% of those on the highest dose) of the patients in the pivotal clinical trials of Aduhelm developed amyloid-related imaging abnormalities (ARIA) that are characterized by fluid retention and microhemorrhages in the brain. The ARIAs weren’t necessarily serious or symptomatic, but they would likely to mean additional MRI scans and visits with neurologists and, therefore, added expense.