Biogen's Aduhelm 'likely' linked to Alzheimer's patient's death, RBC analyst says

In the aftermath of an Alzheimer's disease patient's death, Biogen and industry watchers have been trying to piece together the situation and determine whether the company's recently minted Alzheimer's drug should carry any blame. The answer? Probably so, one analyst says.

After poring over a "detailed case report" obtained through the Freedom of Information Act, RBC Capital Markets' Brian Abrahams wrote to clients that it appears the patient's death was related to a known side effect of Aduhelm called amyloid-related imaging abnormalities, or ARIA. This "was likely due to aducanumab, in our view," Abrahams wrote. Aducanumab is the generic name for Biogen's Aduhelm.

"It appears likely to us that progressively severe cerebral edema/ARIA, which led to status epilepticus, was the inciting factor for the [patient's] deterioration and ultimate demise, and that this is likely to have been caused by aducanumab," Abrahams wrote.

Abrahams is a licensed non-practicing physician, according to RBC Capital Markets' website. 

For its part, Biogen said the RBC report "only provides a partial view of the case." The cause of death remains unknown, and the company is continuing its investigation, Biogen said.

"We take this event very seriously and continue to work with the reporting investigator," a spokesperson said. "We have reported this case to global regulators, investigators, ethics committees, and institutional review boards and we are committed to sharing relevant information with the medical community."

RELATED: Biogen's Aduhelm records one patient death. Is the controversial Alzheimer's drug to blame?

Abrahams' assessment comes a little more than a week after reports surfaced that a patient on Aduhelm had died. The death was reported to the FDA Adverse Event Reporting System (FAERS), the agency disclosed earlier this month. The patient in question was a 75-year-old woman in Canada who died after being diagnosed with ARIA.

From the RBC team's perspective, the case “highlights the potential for the ARIA side effect of beta-amyloid antibodies to be severe.” Such a severe side effect is probably “unusual," the analyst wrote, and is unlikely to warrant a withdrawal of the drug from the market. Still, a potential risk of severe ARIA could spur “more careful labeling/monitoring and may further dissuade uptake,” he wrote.

Aduhelm has faced an uphill climb since its controversial approval this summer. Aduhelm’s label recommends MRI monitoring for ARIA events before starting the treatment and before the 7th and 12th infusions. 

RELATED: Biogen posts more Aduhelm biomarker data and a 'correlation' with Alzheimer's clinical benefit

Aduhelm generated $300,000 in third-quarter sales, coming in far below industry watchers’ expectations.