Single-patient brain study finds less tau damage where amyloid was cleared

The short version

• Researchers at the Perelman School of Medicine published the single-patient brain study in JAMA.[ScienceDaily]
• In the donor's brain, areas where aducanumab cleared amyloid plaques showed little tau buildup, while uncleared neighboring areas showed heavy damage.[ScienceDaily]
• Co-senior author David Wolk called the findings some of the clearest human evidence to date, but the study cannot show how much amyloid removal is needed.[ScienceDaily]

Key facts

• Researchers at the Perelman School of Medicine at the University of Pennsylvania published the study in JAMA and presented it at the 2026 Alzheimer's Association International Conference.[ScienceDaily]
• The patient was diagnosed with mild cognitive impairment in his fifties and received 30 aducanumab doses over four and a half years in a clinical trial.[ScienceDaily]
• The patient died about four years after his last dose.[ScienceDaily]
• Brain regions where amyloid plaques were cleared showed little tau buildup, while nearby regions that still contained amyloid showed higher tau levels and continued neurodegeneration.[ScienceDaily]
• The study cannot establish how much amyloid must be removed to achieve lasting protection or prove that plaque clearance directly caused the differences in tau and brain damage.[ScienceDaily]

Sources

Outlet counts describe coverage, not independent confirmation. Reports may share a wire service or original source.

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