A 26-week analysis of a double-blind, placebo-controlled trial of the Ginkgo biloba extract EGb 761® in dementia

This intent-to-treat (ITT) analysis was performed to provide a realistic image of the efficacy that could be expected after 26 weeks treatment with a 120-mg dose (40 mg t.i.d.) of EGb 761(R) (EGb). The data were collected during a 52-week, double-blind, placebo-controlled, fixed dose, parallel-group, multicenter study. Patients were mildly to severely impaired and diagnosed with uncomplicated Alzheimer's disease or multi-infarct dementia according to ICD-10 and DSM-III-R criteria. The primary outcome measures included the Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-Cog), Geriatric Evaluation by Relative's Rating Instrument (GERRI) and Clinical Global Impression of Change. From 309 patients included in the ITT analysis, 244 patients (76% for placebo and 73% for EGb) actually reached the 26th week visit. In comparison to the baseline values, the placebo group showed a statistically significant worsening in all domains of assessment, while the group receiving EGb was considered slightly improved on the cognitive assessment and the daily living and social behavior. Mean treatment differences favored EGb with 1.3 and 0.12 points, respectively, on the ADAS-Cog (p = 0.04) and the GERRI (p = 0.007). In the group receiving EGb, 26% of the patients achieved at least a 4-point improvement on the ADAS-Cog, compared to 17% with placebo (p = 0.04). On the GERRI, 30% of the EGb group improved and 17% worsened, while the placebo group showed an opposite trend with 37% of patients worsening for 25% improved (p = 0.006). Regarding safety, no differences between EGb and placebo were observed. Copyright (C) 2000 S. Karger AG, Basel.