Closeup of doctor viewing brain scan images

A clot-busting drug administered during a stroke helped lead to the death of a woman taking the experimental Alzheimer’s disease drug lecanemab, a peer-reviewed autopsy analysis has revealed. The Food and Drug Administration will review this and other events linked to lecanemab while making a expected approval decision on the drug this week. 

The report, published Thursday, Jan. 5, in the New England Journal of Medicine, found that the effects of the tissue plasminogen activator (tPA) likely combined with those of lecanemab to cause significant brain bleeding and the stroke patient’s death.

At the time of the stroke, the patient was participating in a lecanemab trial. The new report confirms the opinion of expert observers on the cause of her death. Blood vessels in the patient’s brain were already likely weakened by lecanemab, they theorized. The stroke drug tPA, an anticoagulant given to some stroke patients, likely further increased the risk of a brain bleed.

Bleeding issues

The report “showed extensive brain hemorrhaging, amyloid deposits in the brain, Alzheimer’s disease neuropathologic changes, and inflammation involving amyloid deposits within the blood-vessel walls,” Reuters has reported.

Lecanemab’s makers posted promising clinical trial results in the fall of 2022. Treated patients had a 27% reduced rate of cognitive decline when compared to placebo, the data showed. But there was a 20% rate of adverse events. Brain swelling was experienced by 13% of participants, and about the same percentage were diagnosed with brain microbleeds, according to Reuters. To date, three deaths have been associated with the drug.

FDA approval

If approved by the FDA, lecanemab, made by Biogen and Eisai, would be the second anti-amyloid Azheimer’s drug on the market. Its predecessor Aduhelm was approved under a cloud of controversy, with some FDA advisers and other experts questioning that drug’s safety and efficacy. Aduhelm ultimately was relegated to use in clinical trials only.  

The federal government this week published a withering report on the approval process for Aduhelm. Congressional investigators called the FDA review “atypical” and accused drugmaker Biogen of making decisions based on “corporate greed.” They recommended that the FDA return to its normal review protocol for future drug approval decisions such as that for lecanemab. 

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