Pilot clinical study of Taxifolin Aqua effect in patients with amnestic mild cognitive impairment.

Taxifolin (dihydroquercetin), a potent antioxidant flavonoid, shows promise for neurodegenerative conditions. Our pilot study aimed at evaluation the efficacy and safety of Taxifolin in patients with amnestic mild cognitive impairment (aMCI) and monitored a set of blood measures. Twenty-three patients (18 female; aged 53-87) received dihydroquercetin oral solution for 8 weeks with a 4-week follow-up period in an open-label study design. Thirteen patients with aMCI were monitored as controls. Outcomes were assessed using cognitive status (MMSE, MoCA, FCSRT-IR), neuropsychiatric symptoms' (NPI-Q, HDRS), and rater's impression (CGI) scales, along with blood measures monitoring (glutathione reductase (GR), glutamate dehydrogenase (GDH), and superoxide dismutase (SOD); plasma neutrophil elastase (NE), alpha-1-proteinase inhibitor (alpha-1PI)). Responder classification using composite Z-score changes was based on all clinical scales. Results: Eleven patients were classified as responders, showing significant MMSE and MoCA improvement (mean +2.73 points, p=0.001) sustained through 4-week follow-up. Non-responders and control group showed slight cognitive decline. Composite Z-score changes at the 4-week follow-up revealed differences between responders/non-responders (ANOVA F(2,20)=17.38, p=0.001); biomarker analysis revealed difference in NE/alpha-1PI ratio (p=0.034), SOD (p=0.023), and GR dynamics (p=0.022), which correlated negatively with clinical response (R=-0.547, p=0.007), and baseline GDH (p=0.049). Conclusion: Taxifolin treatment resulted in significant cognitive benefits in ~half of aMCI patients, with effects sustained for one month post-treatment. Biomarker changes reveal possible mechanisms involving oxidative stress modulation and inflammatory pathways. These findings support further controlled trials of Taxifolin in populations at risk of Alzheimer's disease.