A phase II randomized trial of sodium oligomannate in Alzheimer's dementia.

Background: Sodium oligomannate (GV-971), a marine-derived oligosaccharide, is a novel agent that may improve cognition in AD patients.

Methods: The 24-week multicenter, randomized, double-blind, placebo parallel controlled clinical trial was conducted in AD in China between 24 October 2011 and 10 July 2013. The study included a 4-week screening/washout period, followed by a 24-week treatment period. Patients were randomized in a 1:1:1 ratio to receive GV-971 900 mg, 600 mg, or placebo capsule in treatment period, respectively. The primary outcome was cognitive improvement as assessed by changes in Alzheimer's Disease Assessment Scale-cognitive subscale 12-item (ADAS-cog12) scores from baseline to week 24. The secondary efficacy outcomes included CIBIC-Plus, ADCS-ADL, and NPI at 24 weeks after treatment compared with baseline. A subgroup study was assessment of the change in cerebral glucose metabolism by fluorodeoxyglucose positron emission tomography measurements.

Results: Comparing with the placebo group (n = 83, change - 1.45), the ADAS-cog12 score change in the GV-971 600-mg group (n = 76) was - 1.39 (p = 0.89) and the GV-971 900-mg group (n = 83) was - 2.58 (p = 0.30). The treatment responders according to CIBIC-Plus assessment were significantly higher in the GV-971 900-mg group than the placebo group (92.77% vs. 79.52%, p < 0.05). The GV-971 900-mg subgroup showed a lower decline of cerebral metabolic rate for glucose than the placebo subgroup at the left precuneus, right posterior cingulate, bilateral hippocampus, and bilateral inferior orbital frontal at uncorrected p = 0.05. The respective rates of treatment-related AEs were 5.9%, 14.3%, and 3.5%.

Conclusions: GV-971 was safe and well tolerated. GV-971 900 mg was chosen for phase III clinical study.

Trial Registration: ClinicalTrials.gov, NCT01453569 . Registered on October 18, 2011.