Pilot trial links rapamycin to improved brain blood flow in APOE4 carriers

Researchers at the University of Missouri studied healthy adults aged 45–65, including carriers and non-carriers of the APOE4 variant associated with increased Alzheimer’s disease risk. All participants received a low daily dose of rapamycin for four weeks. The study, described as a pilot single-arm trial, assessed cerebral blood flow and metabolic, inflammatory and microbiome profiles. The source does not report the sample size or numerical effect estimates.

Brain blood flow improved in participants with APOE4; the same benefit was not observed in those without the variant. The largest improvements were reported among female APOE4 carriers. The study did not establish whether rapamycin prevents Alzheimer’s disease, delays its onset or preserves memory over time.

These findings are preliminary and concern a short-term physiological outcome, not clinical disease progression. The source provides no detailed safety results or quantitative findings, and further research is needed to determine whether the blood-flow changes translate into lasting brain-health benefits.