The approval of the Alzheimer’s medicine Aduhelm in the United States has already sparked debate. According to a new study, the majority of Alzheimer’s sufferers could not have participated in the clinical studies that led to the approval.
The US Food and Drug Administration gave Aduhelm, also known as aducanumab, expedited approval in June for treating patients with moderate cognitive impairment or mild dementia caused by Alzheimer’s disease.
The decision was quickly criticized, owing to the exorbitant cost of the Biogen medicine ($56,000 per year) and concerns about possible coordination between regulators and the drug’s maker.
This new analysis now identifies further flaws.
The phase 3 trials of the drug showed an increased risk of certain adverse vascular events.
Although the trials excluded elderly patients, those with certain chronic diseases and those using blood thinners, the FDA approved use of the drug in these patient populations without noting any precautions.
“Our findings are concerning given the broad FDA labeling for aducanumab,” said researcher Dr. Timothy Anderson, an assistant professor of medicine at Beth Israel Lahey Health in Boston.
“The public conversation on aducanumab has focused on limited benefit and high costs. It is equally important to consider that the majority of patients with Alzheimer’s disease are likely to face higher risks of adverse events than the patients studied in the trials,” Anderson said in a health system news release.
The researchers examined Medicare claims for 27 million individuals with cognitive — mental — impairment, Alzheimer’s disease, or Alzheimer’s disease-related diseases for the study.
They discovered that the majority of these patients had one or more characteristics that would have disqualified them from participating in the aducanumab clinical trials, such as cardiovascular disease, stroke, blood thinner use, or being over 85.
For example, statistics showed that nearly nine out of ten patients with Alzheimer’s disease-related dementia or Alzheimer’s disease had at least one condition that would have disqualified them from participating in the trials. Similarly, at least one disqualifying condition was present in 85 percent of patients with cognitive impairment.
According to the study, more than three-quarters of patients with Alzheimer’s disease-related dementia had many of these disqualifiers.
“Clinical trials of aducanumab studied relatively healthy participants who do not reflect the majority of older adults with dementia in the U.S.,” Anderson said. “As a result, Medicare should consider restricting coverage for aducanumab to patients who meet the trial eligibility criteria.”
He said additional clinical trials of the high-risk groups excluded from the prior trials should be required and include rigorous study of adverse events.
The report was published Tuesday in the Journal of the American Medical Association.
Two Congressional committees were investigating the procedure that led to the drug’s approval and its high cost in July, according to reports.
Despite the fact that an FDA advisory committee concluded that there was insufficient evidence to support Aduhelm’s effectiveness, the FDA approved it. Three members of the advisory committee subsequently resigned.