A double blind placebo controlled trial of ginkgo biloba extract in acute cerebral ischaemia. 6-Month double-blind randomised clinical trial of Ginkgo biloba extract versus placebo in two parallel groups in patients suffering from peripheral arterial insufficiency. [The effect of Ginkgo biloba extract in patients with intermittent claudication]. A double-blind, placebo controlled study of Ginkgo biloba extract ('tanakan') in elderly outpatients with mild to moderate memory impairment. [Effect of Ginkgo-biloba extract on mental performance. Double-blind study using computerized measurement conditions in patients with cerebral insufficiency]. [Treatment of cerebral aging disorders with Ginkgo biloba extract. A longitudinal multicenter double-blind drug vs. placebo study]. Proof of efficacy of the ginkgo biloba special extract EGb 761 in outpatients suffering from mild to moderate primary degenerative dementia of the Alzheimer type or multi-infarct dementia. Clinical efficacy of Ginkgo biloba special extract EGb 761 in dementia of the Alzheimer type. [Cerebral insufficiency--treatment with Ginkgo-biloba extract. Time of onset of effect in a double-blind study with 60 inpatients].
A double blind placebo controlled trial was conducted in 55 patients of acute ischaemic stroke. Twenty one and twenty six patients were randomly allotted in group A and group B respectively. In group A, the patients received 40 mg Ginkgo biloba extract at 6 hourly intervals along with routine management. The placebo tablets were dispensed in the tablet form of same size, shape and colour and were given in the same way. After the patients were subjected to computerized tomographic (CT) scan to confirm acute ischaemic infarction, they were assessed on Mathew's scale and reassessed, at 2 weeks and 4 weeks of drug/placebo administration. Both groups showed significant improvement in Mathew's scale score after 2 weeks and 4 weeks. The difference in degree of change was negligible (p > 0.05) in either group. Estimation of relative changes of neurological deficit based on baseline values also showed negligible (p > 0.05) difference. A trial of Ginkgo biloba extract within 6 hours of stroke in a larger dose and in larger sample could be beneficial clinically in patients of cerebral ischaemic infarct, and needs further study. The usefulness of the plant extract has been demonstrated clinically and experimentally in more than 40 trials of chronic cerebral ischaemia, done elsewhere. This was not evident in our study as our study group was different (more than 48 hours after stroke). There appears to be no contraindication or adverse effect of this medication (Ginkgo biloba) in acute ischaemic stroke. 79 patients suffering from peripheral arteriopathy (Fontaine's stage IIb) completed a 6-month double-blind randomised clinical trial of Ginkgo biloba extract (GBE) (as coated tablets containing 40 mg GBE; rökan) versus placebo in two parallel groups. From the results of measurements of pain-free walking distance, maximum walking distance and plethysmography recordings, GBE was shown to be active and significantly superior to placebo. These results correlated with the physician's and patients' overall assessment of response to treatment. Eighteen patients with stable intermittent claudication were randomized in a double blind cross-over study comparing the effects of the Ginkgo biloba extract GB-8 at a dose of 120 mg o.d. with placebo. All patients were treated for three months with the active extract and three months with placebo. The effects of treatment on arterial insufficiency were quantified by measurements of systemic and peripheral systolic blood pressures, and pain-free and maximal walking distances on a tread-mill. Questionnaires based on visual analogue scales were used to quantify the severity of leg pain, impairment of concentration, and inability to remember. Short-term memory was objectively assessed. We did not find any significant changes in either peripheral blood pressures, walking distances or the severity of leg pain. Systemic blood pressure was reduced both by placebo and GB-8. The impairment of concentration and the inability to remember were both reduced, when comparing results during active treatment to placebo. Short-term memory did not change significantly. In conclusion, our study has shown that treatment with the Ginkgo biloba extract GB-8 improves some cognitive functions in elderly patients with moderate arterial insufficiency, whereas the extract did not change signs and symptoms of vascular disease in the patients. Thirty-one patients over the age of 50 years and showing a mild to moderate degree of memory impairment entered a 6-month double-blind, placebo controlled, parallel group design study to assess the effects of a standardized Ginkgo biloba extract (containing 24% flavonoid glycosides and 6% terpenes) on cognitive function. Patients were allocated at random to receive oral doses of 40 mg Ginkgo biloba extract or identical placebo 3-times daily. Assessments were made at baseline and after 12 and 24 weeks of treatment using a range of psychometric tests. Efficacy data were available for 27 patients (15 in the placebo group and 12 in the active treatment group). Statistical analysis of the data as compared to baseline suggests that Ginkgo biloba extract had a beneficial effect on cognitive function in this group of patients. Performance on the Digit Copying sub-test of the Kendrick battery was significantly improved at both 12 and 24 weeks, while the median speed of response on a computerized version of a classification task also showed a significant superiority over placebo at 24 weeks. Problem: The effect of ginkgo biloba extract EGb 761 on basic parameters of mental performance. Patients: Seventy-two outpatients with cerebral insufficiency at three test centers. Study design: Double-blind, randomized placebo-controlled study of 24 weeks duration. Test parameters: Psychometric computer-aided examination of the short-term memory and basic learning rate. Results: Statistically significant improvement in the shortterm memory after 6 weeks and of the learning rate after 24 weeks in the test substance group, but not in the placebo group (longitudinal analysis). The difference between the test substance and placebo groups (horizontal analysis) reached statistical significance in the 24th week. Conclusions: Treatment with ginkgo biloba extract EGb 761 improves mental/mnestic performance. The effectiveness of Ginkgo biloba extract in the treatment of cerebral disorders due to ageing was evaluated in a multicentric, double-blind, drug versus placebo trial involving 166 patients. In this study carried out under strict methodological conditions a specially devised geriatric clinical evaluation scale was used. The results confirmed that Ginkgo biloba extract is effective against cerebral disorders due to ageing. The difference between control and treatment groups became significant at 3 months and increased during the following months. These results were concordant with the overall clinical assessment made by the specialist in charge. The efficacy of the ginkgo biloba special extract EGb 761 in outpatients with presenile and senile primary degenerative dementia of the Alzheimer type (DAT) and multi-infarct dementia (MID) according to DSM-III-R was investigated in a prospective, randomized, double-blind, placebo-controlled, multi-center study. After a 4-week run-in period, 216 patients were included in the randomized 24-week treatment period. These received either a daily oral dose of 240 mg EGb 761 or placebo. In accordance with the recommended multi-dimensional evaluation approach, three primary variables were chosen: the Clinical Global Impressions (CGI Item 2) for psychopathological assessment, the Syndrom-Kurztest (SKT) for the assessment of the patient's attention and memory, and the Nürnberger Alters-Beobachtungsskala (NAB) for behavioral assessment of activities of daily life. Clinical efficacy was assessed by means of a responder analysis, with therapy response being defined as response in at least two of the three primary variables. The data from the 156 patients who completed the study in accordance with the study protocol were taken into account in the confirmatory analysis of valid cases. The frequency of therapy responders in the two treatment groups differed significantly in favor of EGb 761, with p < 0.005 in Fisher's Exact Test. The intent-to-treat analysis of 205 patients led to similar efficacy results. Thus, the clinical efficacy of the ginkgo biloba special extract EGb 761 in dementia of the Alzheimer type and multi-infarct dementia was confirmed. The investigational drug was found to be well tolerated. Among the psychiatric illnesses associated with old age primary degenerative dementia of the Alzheimer type (DAT) has gained increasing importance in recent years. Even though a curative treatment of the disease is currently impossible, various drugs can be used to slow down its progression. In the present study the influence of oral treatment with 240 mg/day of Ginkgo bilabo special extract EGb 761 (Tebonin forte, manufactured by Dr Willmar Schwabe, Karlsruhe) on the clinical course of DAT was investigated in a double-blind, randomized, placebo-controlled parallel-group design in 20 outpatients. The duration of treatment was 3 months. The primary outcome variable was the sum score in the SKT-test for the determination of attention and memory. Other psychometric tests (trailmaking test, ADAS, CGI) and electrophysiological investigations (EEG topography) were evaluated descriptively. Although the active-treatment group, with a mean sum score of 19.67 points in the, S.K.T., had a poorer baseline level than the placebo group (18.11 points), it experienced an improvement to 16.78 points under treatment with EGb 761 whereas the placebo group deteriorated to 18.89 points. The differences between the baseline and final values formed the basis for a statistical group comparison, which gave a result favourable to EGb 761, at a significance level of p < .013. In addition to this psychometric confirmation of efficacy, certain descriptive trends were found at the psychopathological (Clinical Global Impression) and dynamic functional (EEG findings) levels, which can be interpreted as evidence of effectiveness of Ginkgo biloba special extract EGb 761 in mild to moderate dementia and of local effects in the central nervous system. Inter-group differences in the ADAS cognitive and non-cognitive subscales did not reach statistical significance, probably because of the small sample size. Sixty inpatients with cerebral insufficiency and the leading symptom depressive mood, were treated in a double-blind study for 6 weeks with a daily dose of 160 mg Ginkgo biloba extract or placebo. After 2, 4 and 6 weeks, changes in 12 typical symptoms in comparison with the last examination, were evaluated. In the group receiving placebo, small, but progressive improvements were observed. In the Ginkgo-biloba group, the overall number of improvements was significantly larger. After 2 weeks the differences were marked for only a few of the symptoms; after 4 and 6 weeks in contrast, in 11 of the 12 symptoms. The largest number of improvements in the Ginkgo-biloba group was observed between the 2nd and 4th weeks of treatment. In this period, about two-thirds of the patients on Ginkgo-biloba, and about one-fifth of the patients on placebo showed improvements.
There was no convincing evidence from trials of sufficient methodological quality to support the routine use of Ginkgo biloba extract to promote recovery after stroke. High-quality and large-scale randomised controlled trials are needed to test its efficacy.