Most With AD, MCI Would Have Been Excluded From Aducanumab Clinical Trials

Overall, 92.2, 91.0, and 85.5 percent of Medicare beneficiaries with ADRDs, Alzheimer disease, and MCI met at least one of the exclusion criteria

THURSDAY, Sept. 16, 2021 (HealthDay News) — The two phase 3 clinical trials on which the approval of aducanumab is based used exclusion criteria that would exclude the vast majority of Medicare beneficiaries with Alzheimer disease-related disorders (ADRDs), Alzheimer disease, and mild cognitive impairment (MCI), according to a research letter published online Sept. 9 in the Journal of the American Medical Association.

Timothy S. Anderson, M.D., from Beth Israel Deaconess Medical Center in Boston, and colleagues evaluated whether patients enrolled in aducanumab trials were representative of patients with dementia enrolled in Medicare by estimating the proportions of Medicare beneficiaries with Alzheimer disease or MCI who would have been excluded from the trials. Three cohorts of patients potentially eligible for aducanumab treatment were identified: those with ADRDs, those with Alzheimer disease specifically, and those with MCI. Data were included for 27,785,076 Medicare beneficiaries, of whom 10.3, 3.7, and 1.4 percent had been diagnosed with ADRDs, Alzheimer disease, and MCI, respectively.

The researchers found that 92.2, 91.0, and 85.5 percent of patients with ADRDs, Alzheimer disease, and MCI, respectively, met at least one of the trial exclusion criteria, with the most common exclusion criteria being cardiovascular disease, conditions associated with anticoagulation, chronic kidney disease, and age older than 85 years. The majority of patients met multiple exclusion criteria, including 77.4 and 64.4 percent of those with ADRDs and MCI, respectively.

“Medicare should consider restricting coverage for aducanumab to patients who meet the trial eligibility criteria, and additional clinical trials of the high-risk groups excluded from the prior trials should be required, including rigorous study of adverse events, prior to broadening coverage,” Anderson said in a statement.

Anderson disclosed receiving personal fees from Alosa Health.