Introduction: Human studies on low-dose resveratrol are scarce. This study aims to evaluate the safety, tolerability, and efficacy of an oral preparation of resveratrol, glucose, and malate (RGM) in slowing the progression of Alzheimer's disease (AD).
Methods: Thirty-nine subjects with mild to moderate AD who were free of life-threatening disease and who did not have contraindications to the use of the study product were screened. Progression of AD was measured by change in the cognitive portion of the Alzheimer's Disease Assessment Scale-cognitive subscale. Secondary outcomes included Clinician's Global Impression of Change, Mini-Mental State Examination, Alzheimer's Disease Cooperative Study-Activities of Daily Living Scale, and Neuropsychiatric Inventory. 15 mL of the following preparation per dose, i.e., 5 g dextrose, 5 g malate, and 5 mg resveratrol, or matching placebo was ingested with an 8 oz glass of commercial unsweetened grape juice twice a day for 1 year. Group differences in the rate of change in the outcome measures were examined using generalized estimating equations.
Results: The treatment and control groups were similar on all of the screening variables. At 12 months, change scores on Alzheimer's Disease Assessment Scale-cognitive subscale, Mini-Mental State Examination, Alzheimer's Disease Cooperative Study-Activities of Daily Living Scale, or Neuropsychiatric Inventory all showed less deterioration in the treatment than the control group; however, none of the change scores reached statistical significance. The most common AE were falls, all in the control group. None of the falls were deemed to be study related.
Conclusion: Low-dose oral resveratrol is safe and well tolerated. Interpretation of the effects on clinical outcomes trajectories remains uncertain. A larger study is required to determine whether low-dose resveratrol may be beneficial.
Trial registration: ClinicalTrials.gov (NCT00678431), Registered 05/15/2008.
Keywords: Double-blind methods; Drug therapy; Efficacy; Resveratrol; Safety.