Alzheimer’s research breakthrough: diabetes drug reduces toxic tau protein

Two widely available drugs — the anti-diabetic empagliflozin and intranasal insulin — have been found to improve brain health in people with mild cognitive impairment and early-stage Alzheimer’s disease, according to a new clinical study by the Wake Forest University School of Medicine in the U.S.

The study, published in the journal Alzheimer’s & Dementia of the Alzheimer’s Association, is the first to examine empagliflozin in non-diabetic Alzheimer’s patients and shows encouraging results in memory, brain health, and cerebral blood flow, CE Report quotes ANA-MPA.

Researchers noted that, despite recent approvals of anti-amyloid drugs, their benefits remain limited and many patients cannot take them due to side effects or medical contraindications. Moreover, such drugs do not target the metabolic and vascular dysfunctions that accelerate disease progression and do not help restore brain function after damage occurs.

The four-week trial involved 47 adults, with an average age of 70, who had mild cognitive impairment or early Alzheimer’s. Participants were randomly assigned to one of four groups: one received only intranasal insulin, one only empagliflozin, one both drugs, and one a placebo. The insulin was delivered using a precision device that sent it directly to the brain through the nasal passage, bypassing the bloodstream — and in higher doses than in previous studies.

Both drugs were found to be safe and well-tolerated, with mild side effects across all groups. Results revealed distinct benefits from each drug:

• Intranasal insulin improved performance on cognitive tests detecting early memory and thinking changes. Brain imaging showed increased white matter integrity and improved blood flow to memory-related regions. It also reduced levels of GFAP, a blood biomarker of astrocyte dysfunction elevated in Alzheimer’s.

• Empagliflozin, on the other hand, significantly reduced tau protein levels in cerebrospinal fluid — a key pathological marker of Alzheimer’s — along with other indicators of neuronal and vascular dysfunction. It also altered blood flow patterns in key brain areas and raised HDL (“good”) cholesterol levels, demonstrating positive metabolic effects even in non-diabetic patients.

Both drugs influenced proteins in the cerebrospinal fluid and blood in ways suggesting activation of protective immune responses and reduction of harmful inflammation.

Since both medications are already approved for other conditions, they could potentially be made available to Alzheimer’s patients faster than entirely new drugs. Researchers now plan larger, longer-term studies in individuals with early and preclinical Alzheimer’s disease.

The study was supported by the Alzheimer’s Association through its Part the Cloud program, which has raised nearly $90 million to fund 72 clinical trials aimed at slowing, halting, or curing Alzheimer’s disease.