Efficacy and safety of Ginkgo biloba extract EGb 761 in mild cognitive impairment with neuropsychiatric symptoms: a randomized, placebo-controlled, double-blind, multi-center trial

Objective: The study was conducted to explore the effects of EGb 761 (Dr. Willmar Schwabe GmbH & Co. KG, Karlsruhe, Germany) on neuropsychiatric symptoms (NPS) and cognition in patients with mild cognitive impairment (MCI).

Methods: One hundred and sixty patients with MCI who scored at least 6 on the 12-item Neuropsychiatric Inventory (NPI) were enrolled in this double-blind, multi-center trial and randomized to receive 240 mg EGb 761 daily or placebo for a period of 24 weeks. Effects on NPS were assessed using the NPI, the state sub-score of the State-Trait Anxiety Inventory and the Geriatric Depression Scale. Further outcome measures were the Trail-Making Test (A/B) for cognition and global ratings of change. Statistical analyses followed the intention-to-treat principle.

Results: The NPI composite score decreased by 7.0 ± 4.5 (mean, standard deviation) points in the EGb 761-treated group and by 5.5 ± 5.2 in the placebo group (p = 0.001). Improvement by at least 4 points was found in 78.8% of patients treated with EGb 761 and in 55.7% of those receiving placebo (p = 0.002). Superiority of EGb 761 over placebo (p < 0.05) was also found for the State-Trait Anxiety Inventory score, the informants' global impression of change, and both Trail-Making Test scores. There were statistical trends favoring EGb 761 in the Geriatric Depression Scale and the patients' global impression of change. Adverse events (all non-serious) were reported by 37 patients taking EGb 761 and 36 patients receiving placebo.

Conclusions: EGb 761 improved NPS and cognitive performance in patients with MCI. The drug was safe and well tolerated.