PubMed Health⌕ Search

Biomedical subjects

M Kieser

Publications and source records attributed to M Kieser.

At least 19 recordsLinked to original sources
PubMed2006

Ginkgo biloba special extract EGb 761 in generalized anxiety disorder and adjustment disorder with anxious mood: a randomized, double-blind, placebo-controlled trial.

Ginkgo biloba special extract EGb 761, an anti-dementia drug, enhances cognitive functioning and stabilizes mood in cognitively impaired elderly subjects. Moreover, EGb 761 had been found to alleviate symptoms of anxiety in people with mental decline, therefore it was now tested for clinical efficacy in younger patients suffering from anxiety. One hundred and seven patients with generalized anxiety disorder (GAD, n=82) or adjustment disorder with anxious mood (ADWAM, n=25) according to the diagnostic and statistical manual of mental disorders, third edition - revised (DSM-III-R) were randomized to daily doses of 480 mg EGb 761, 240 mg EGb 761 or placebo for 4 weeks. Intention-to-treat (ITT) analyses were performed on the primary outcome measure, the Hamilton rating scale for anxiety (HAMA), and the secondary variables, the clinical global impression of change (CGI-C), the Erlangen anxiety tension and aggression scale (EAAS), the list of complaints (B-L'), and the patient's global rating of change. The HAMA total scores decreased by -14.3 (+/-8.1), -12.1 (+/-9.0) and -7.8 (+/-9.2) in the high-dose EGb 761, the low-dose EGb 761 and the placebo group, respectively. Changes were significantly different from placebo for both treatment groups with p=0.0003 (high-dose group) and p=0.01 (low-dose). Regression analyses revealed a dose-response trend (p=0.003). EGb 761 was significantly superior to placebo on all secondary outcome measures. It was safe and well tolerated and may thus be of particular value in elderly patients with anxiety related to cognitive decline.

Adjustment Disorders↗
PubMed2006

Comparison of Hypericum extract WS 5570 and paroxetine in ongoing treatment after recovery from an episode of moderate to severe depression: results from a randomized multicenter study.

OBJECTIVE: To test and compare the efficacy and safety of Hypericum extract WS 5570 to paroxetine, a potent SSRI, in patients suffering from moderate or severe depression according to DSM-IV criteria. METHODS: In a multicenter, randomized, double-blind phase III study, the changes in moderate to severe major depression DSM-IV; 17-item Hamilton Depression Rating Scale (HAM-D total>or=22) after an acute treatment with Hypericum extract WS 5570 or paroxetine were analyzed in a 16-week continuation phase for relapse prevention. Patients with a HAM-D total score decrease of >or=50% during the 6 weeks of acute treatment were asked to continue the treatment for another 4 months. One-hundred and thirty-three adult out-patients who received maintenance doses of 900 (n=33) or 1800 mg/d (n=38) of WS 5570 and 20 (n=28) or 40 mg/d (n=34) of paroxetine, respectively, were included. The relevant dosage was already fixed during the acute treatment. RESULTS: Between baseline of the acute phase and end of continuation treatment the HAM-D total score decreased from 25.3+/-2.5 (mean+/-SD) to 4.3+/-6.2 points for WS 5570 and from 25.3+/-2.6 to 5.2+/-5.5 points for paroxetine (p=0.49, two-sided t-test; median relative decrease: 92.0 and 85.5%, respectively). During maintenance treatment alone (day 154-day 42), 61.6% of the patients randomized to WS 5570 and 54.6% treated with paroxetine showed an additional reduction (p=0.59) with respect to the HAM-D total score. Remission (HAM-D endpoint total score below 8) occurred in 81.6% (31 patients) of the patients for WS 5570 and in 71.4% (30 patients) for paroxetine (p=0.29). Three patients in the WS 5570 group and 2 patients in the paroxetine group showed a HAM-D increase>5 points during continuation treatment. In the continuation phase there were 0.006 adverse events per day of exposure for WS 5570 and 0.007 events for paroxetine. CONCLUSION: This study showed that WS 5570 and paroxetine were similarly effective in preventing relapse in a continuation treatment after recovery from an episode of moderate to severe depression and point therefore to an important alternative treatment option for long-term relapse-prevention.

Adolescent↗
PubMed2005

Acute treatment of moderate to severe depression with hypericum extract WS 5570 (St John's wort): randomised controlled double blind non-inferiority trial versus paroxetine.

OBJECTIVE: To investigate the efficacy of hypericum extract WS 5570 (St John's wort) compared with paroxetine in patients with moderate to severe major depression. DESIGN: Randomised double blind, double dummy, reference controlled, multicentre non-inferiority trial. SETTING: 21 psychiatric primary care practices in Germany. PARTICIPANTS: 251 adult outpatients with acute major depression with total score > or = 22 on the 17 item Hamilton depression scale. INTERVENTIONS: 900 mg/day hypericum extract WS 5570 three times a day or 20 mg paroxetine once a day for six weeks. In initial non-responders doses were increased to 1800 mg/day hypericum or 40 mg/day paroxetine after two weeks. MAIN OUTCOME MEASURES: Change in score on Hamilton depression scale from baseline to day 42 (primary outcome). Secondary measures were change in scores on Montgomery-Asberg depression rating scale, clinical global impressions, and Beck depression inventory. RESULTS: The Hamilton depression total score decreased by mean 14.4 (SD 8.8) points, corresponding to 56.6% (SD 34.3%) of the baseline value, in the hypericum group and by 11.4 (SD 8.6) points (44.8% (SD 33.5%) of baseline value) in the paroxetine group (intention to treat analysis; similar results were observed in the per protocol analysis). The intention to treat analysis (lower one sided 97.5% confidence limit 1.5 points for the difference hypericum minus paroxetine) and the per protocol analysis (lower confidence limit 0.7 points) showed non-inferiority of hypericum and statistical superiority over paroxetine. The lower limits in both cases exceeded the pre-specified non-inferiority margin of -2.5 points and the superiority margin of 0. The incidence of adverse events was 0.035 and 0.060 events per day of exposure for hypericum and paroxetine, respectively. CONCLUSIONS: In the treatment of moderate to severe major depression, hypericum extract WS 5570 is at least as effective as paroxetine and is better tolerated.

Antidepressive Agents, Second-Generation↗
PubMed2005

Predicting stable treatment response in patients with major depression treated with hypericum extract WS 5570/5572.

OBJECTIVE: Recent research with several synthetic antidepressants indicates that early improvement during the initial weeks of treatment may be a highly sensitive predictor of therapeutic success in major depression. We investigated whether early improvement is sensitive and specific in predicting sustained response and non-response to antidepressant treatment with Hypericum extract WS(R) 5570/5572 and whether the results reported for synthetic antidepressants apply to these Hypericum extracts as well. METHODS: We analyzed original data of 3 double-blind, randomized trials including a total of 594 adult out-patients suffering from major depression according to DSM-IV criteria, who received well-characterized Hypericum extract preparations WS(R) 5570, WS(R) 5572, WS(R) 5573 or placebo for 6 weeks. The main outcome measure was the prediction of a sustained > or = 50 % decrease of the Hamilton Depression Scale (HAM-D) total score versus baseline ('sustained response') by the presence of > or =20 % HAM-D total score improvement after 1 and 2 weeks of treatment ('early improvement'). RESULTS: For Hypericum extract, early improvement had a sensitivity of 87 % (95 % confidence interval [CI], 82-93 %) and a specificity of 54 % (95 % CI, 45-62 %) at day 14, and a sensitivity of 43 % (95 % CI, 35-51 %) and a specificity of 86 % (95 % CI, 80-92 %) at day 7 for predicting sustained response. After 2 weeks of treatment, 78 % (95 % CI, 69-87 %) of the patients who failed to improve did not show sustained response later during treatment. CONCLUSION: A substantial fraction of the patients treated with Hypericum extracts WS(R) 5570/5572 showed a meaningful reduction of depressive symptoms during the first two weeks of treatment (early improvement), which was found to be a sensitive predictor of sustained response. The results determined for the herbal extracts were comparable to those for effective synthetic antidepressants investigated previously.

Adult↗
PubMed2005

Identification of adverse drug reactions by evaluation of a prescription database, demonstrated for "risk of bleeding".

OBJECTIVE: Information about adverse drug reactions plays an important role when assessing the benefit/risk profile of a drug. Identifying rare adverse drug reactions, however, is a difficult task. This paper illustrates the advantages of using a prescription database for this purpose. METHODS: The mediplus database used in our analysis covered data from 320,644 outpatients observed between July 1999 and June 2002. The example of bleeding complications during intake of antidementia drugs is used to illustrate this approach. The comparison of cohorts and subgroups is nearly always a problem in surveys. For our analyses we considered a set of patients who had taken a selected medication for a certain period of time and compared the frequency of adverse events with those occurring when the same patients did not take this medication. Hence, the comparison with versus without a certain medication is based on the same set of patients as in a cross-over study. RESULTS: Our evaluations indicate that the rate of bleeding complications is low when taking any of the widely used antidementia drugs, glutamate modulators, cholinesterase inhibitors, calcium antagonists or the phytomedicine Ginkgo biloba. CONCLUSION: Basing the comparison of the rates of complications during periods with and without intake of a certain drug on the same set of patients may be a useful tool for assessing adverse drug reactions from data reported in prescription databases.

Adult↗
PubMed2004

Continuation and long-term maintenance treatment with Hypericum extract WS 5570 after successful acute treatment of mild to moderate depression--rationale and study design.

Unipolar major depression is often a chronic disease that may require lifelong prophylaxis. Recovery from an acute episode is followed by 4-6 months of relapse prevention. After that, long-term maintenance treatment is administered to avoid recurrence. We present the rationale and design of an ongoing double-blind, randomized, placebo-controlled trial investigating the efficacy of Hypericum extract WS 5570 in relapse prevention in recurrent unipolar depression. An estimated sample of 425 adults with recurrent, mild to moderate major depression (ICD-10 and DSM-IV criteria), > or = 3 previous episodes (last 5 years) and a total score > or = 20 points on the 17-item Hamilton Rating Scale for Depression (HAMD) will be included. After a one-week wash out patients receive 3 x 300 mg/day WS 5570 single-blind for 6 weeks. Responders are randomized to 26 weeks of double-blind continuation treatment with 3 x 300 mg/day WS 5570 or placebo. Patients completing continuation treatment without relapse enter 52 weeks of doubleblind maintenance treatment, where those treated with WS 5570 are re-randomized to 3 x 300 mg/day WS 5570 or placebo. The primary outcome measure is the time to relapse during continuation treatment (HAMD > or = 16, clinical diagnosis of depression, or premature treatment termination for inefficacy). Hypericum extract, with its favourable tolerability profile, could be an interesting option for long-term prophylaxis. The trial was designed according to current consensus and guidance. Notably, it includes long-term prophylactic treatment with the same drug and the same therapeutic dose applied during acute treatment, uses well-defined outcome measures and provides a clear distinction between relapse and recurrence.

Acute Disease↗
PubMed2002

[Pharmaco-economic evaluation of Ginkgo special extract EGb 761 for dementias in Austria].

The aim of the study was to carry out an economic evaluation of the therapeutic effects achievable with ginkgo special extract Egb 761 in dementia in Austria. The care-cost savings that could be achieved with ginkgo special extract Egb 761 therapy were estimated on the basis of the extent to which it delayed growing dependency and an increasing need for care--this being ascertained from the active treatment/placebo differences on GERRI after 6 months of treatment with Egb 761 and evaluated using the rates of the Austrian Federal Care Allowance Law--and compared with the cost of this therapy. The duration of illness, the start and duration of treatment, and the Egb 761 dose were varied in a series of scenarios in a sensitivity analysis. In all the scenarios the care-cost savings exceed the costs of the ginkgo special extract Egb 761 therapy. The cost/savings ratio is most favourable when the treatment is started early and when it is used in patients with dementia of the Alzheimer type. For every month by which the transition from the stage requiring a small to moderate amount of care to the stage requiring considerable or very considerable care can be delayed, one can save 812 [symbol: see text]. Prescribing ginkgo special extract Egb 761 for dementia makes sense from the national economic viewpoint because the product can yield care-cost savings that exceed the cost of the treatment itself.

Activities of Daily Living↗
PubMed2002

Influence of the severity of cognitive impairment on the effect of the Gnkgo biloba extract EGb 761 in Alzheimer's disease.

OBJECTIVE: To explore the treatment effect of EGb 761((R)) (EGb) in Alzheimer's disease depending on baseline severity. METHODS: We applied stratification to the intent-to-treat data set collected during a 52-week, randomized, double-blind, placebo-controlled, parallel-group, multicenter study with 120 mg of EGb, using cutoff points of 23 and 14 for the Mini-Mental State Examination (MMSE) score. Outcome measures used were the cognitive subscale of the Alzheimer's Disease Assessment Scale (ADAS-Cog) and the Geriatric Evaluation by Relative's Rating Instrument (GERRI). RESULTS: In the severity stratum 1 (MMSE >23), the placebo group did not show significant changes, while the EGb group improved significantly by 1.7 points on the ADAS-Cog and by 0.09 points on the GERRI. In the severity stratum 2 (MMSE <24), the placebo group worsened by 4.1 points on the ADAS-Cog and 0.18 points on the GERRI, whereas the EGb group showed 60% less decline on the ADAS-Cog (treatment difference of 2.5 points) and no change on the GERRI (treatment difference of 0.25 points). The most severely impaired subgroup (MMSE <15) showed slightly more pronounced worsening for both treatment groups. However, in comparison to placebo, EGb induced virtually the same magnitude of effect as was observed in the entire stratum 2. CONCLUSIONS: The results of this retrospective analysis indicated that a treatment effect favorable to EGb could be observed with respect to cognitive performance (p = 0.02) and social functioning (p = 0.001) regardless of the stage of dementia, whether mild or moderately severe. However, the relative changes from baseline measured at endpoint depended heavily on the severity at baseline. Improvement was observed in the group of patients with very mild to mild cognitive impairment, while in more severe dementia, the mean EGb effect should be considered more in terms of stabilization or slowing down of worsening, as compared to the greater deterioration observed with placebo.

Aged↗
PubMed2002

Efficacy of St. John's wort extract WS 5570 in major depression: a double-blind, placebo-controlled trial.

OBJECTIVE: In a double-blind, randomized, placebo-controlled trial with 375 patients the authors investigated the antidepressant efficacy and safety of 300 mg t.i.d. of hydroalcoholic Hypericum perforatum extract WS 5570. METHOD: The study participants were male and female adult outpatients with mild to moderate major depression (single or recurrent episode, DSM-IV criteria). After a single-blind placebo run-in phase, the patients were randomly assigned, 186 to WS 5570 and 189 to placebo, after which they received double-blind treatment for 6 weeks. Follow-up visits were held after 1, 2, 4, and 6 weeks. The primary outcome measure was the change from baseline in the total score on the 17-item Hamilton Depression Rating Scale. In addition, analyses of responders (patients with at least a 50% reduction in Hamilton total score) and patients with remissions (patients with a total score of 6 or less on the Hamilton scale at treatment end) were carried out, and subscale/subgroup analyses were conducted. The design included an adaptive interim analysis performed after random assignment of 169 patients with options for group size adjustment or early termination. RESULTS: Compared to placebo, WS 5570 produced a significantly greater reduction in total score on the Hamilton depression scale and significantly more patients with treatment response or remission. It was more effective in patients with higher baseline Hamilton scores and led to global reduction of depression-related core symptoms, assessed with the melancholia subscale of the Hamilton scale. The placebo and WS 5570 groups had comparable adverse events. CONCLUSIONS: H. perforatum extract WS 5570 was found to be safe and more effective than placebo for the treatment of mild to moderate depression.

Adolescent↗
PubMed2001

A comparison of methods for adaptive sample size adjustment.

In fixed sample size designs, precise knowledge about the magnitude of the outcome variable's variance in the planning phase of a clinical trial is mandatory for an adequate sample size determination. Wittes and Brittain introduced the internal pilot study design that allows recalculation of the sample size during an ongoing trial using the estimated variance obtained from an interim analysis. However, this procedure requires the unblinding of the treatment code. Since unblinding of an ongoing trial should be avoided whenever possible, there should be some benefit of this design compared with blinded sample size recalculation procedures to justify the unveiling of the treatment code. In this paper, we compare several sample size recalculation procedures with and without unblinding. The simulation results indicate that the procedures behave similarly. In particular, breaking of the blind is not required for an efficient sample size adjustment. We also compare these pure sample size adaptation procedures with study designs which additionally allow for early stopping. Evaluation of the cumulative distribution function of the resulting sample sizes shows that the option for early stopping may lead to lower expectation but generally to a higher variability. The procedures are illustrated by an example of a trial in the treatment of depression.

Computer Simulation↗
PubMed2001

Efficacy of kava-kava in the treatment of non-psychotic anxiety, following pretreatment with benzodiazepines.

A 5-week randomized, placebo-controlled, double-blind study was carried out to investigate the efficacy of kava-kava special extract WS1490 in non-psychotic nervous anxiety, tension and restlessness states. During the first treatment week, the study dose drug was increased from 50 mg to 300 mg per day and pretreatment with benzodiazepines was tapered off over 2 weeks. These dosage adjustments were followed by 3 weeks of monotherapy with WS1490 or placebo. Outcome measures were the differences between baseline and end of treatment on the Hamilton Anxiety Scale (HAMA) and on a subjective well-being scale (Bf-S), as well as the benzodiazepine withdrawal symptoms. Changes in the Erlanger Anxiety, Tension and Aggression Scale (EAAS) and Clinical Global Impressions (CGI) were analyzed as secondary measures. Treatment safety was checked by interviews, adverse event reports and laboratory investigations. Forty patients (2x20) were included into the study. WS1490 was superior to placebo regarding the HAMA (P=0.01) and Bf-S (P=0.002) total scores and all secondary efficacy measures. The tolerance of WS1490 was not inferior to placebo. The study confirms the anxiolytic efficacy and good tolerance of WS1490 and shows that a further symptom reduction is possible after a change-over from benzodiazepine treatment.

Adult↗
PubMed2001

Efficacy and tolerability of hypericum extract WS 5572 versus placebo in mildly to moderately depressed patients. A randomized double-blind multicenter clinical trial.

We have investigated the antidepressant efficacy and safety of Hypericum perforatum (St. John's wort) extract WS5572 in a double-blind, placebo-controlled multicenter clinical trial. 72 patients (WS 5572: 37, placebo: 35) with a diagnosis of mild to moderate major depressive disorder (according to DSM-IV criteria) were randomized in 42 days of treatment with either 300 mg WS5572 t.i.d. or placebo. The primary efficacy variable was the change of the 17-item Hamilton Depression Scale (HAMD) total score between baseline and double-blind treatment. The study was conducted with an adaptive interim analysis, which led to early stopping because convincing treatment efficacy could already be demonstrated. Group differences in favor of WS 5572 were descriptively apparent as early as day 7 of randomized treatment and were statistically significant at days 28 (p = 0.011) and day 42 (p < 0.001). Between baseline and treatment end, the HAMD total score decreased from 19.7 +/- 3.4 to 8.9 +/- 4.3 points in the Hypericum group and from 20.1 +/- 2.6 to 14.4 +/- 6.8 points in the placebo group (mean +/- SD). Responder rates were consistently higher in the Hypericum group. Comparable group differences in favor of WS 5572 were also found for von Zerssen's Depression Scale (D-S; self-rating), Clinical Global Impressions (CGI) and a global patient's self-assessment (GPA). Tolerability was very good in both groups, with no adverse drug reactions and no clinically relevant changes in safety parameters. The results indicate that Hypericum extract WS 5572 is an effective and well-tolerated drug for the treatment of mild to moderate major depressive disorder.

Adult↗
PubMed2001

A loss-function based approach for dose selection in two-stage dose-response trials.

BACKGROUND: Adaptive two-stage designs are a flexible tool in drug development and have the potential for an improvement of power over one-stage designs. In an adaptive two-stage dose-response trial, the dose-response relationship is examined in a preplanned interim analysis. If efficacy has not yet been proved, a subset of the most favourable doses may be selected for the second stage. This design offers the opportunity to combine dose selection and proof of efficacy within a single trial. METHODS: We consider a change-point regression model describing the dose-response relationship. In this framework, selection of the most favourable dose can be achieved by estimating the change point in the regression model. We introduce a change-point estimator that can be optimised by a loss-function based approach, taking into account both efficacy and safety aspects. We investigate the power characteristics of our approach. RESULTS: The proposed procedure performs well with regard to statistical power. The proposal demonstrates the feasibility of simultaneous modelling of efficacy and safety aspects by a loss-function based approach. CONCLUSION: Adaptive two-stage designs, in conjunction with an elaborated dose-selection rule, can support the decision about the suitable dose to use, leading to a considerable gain in power (or saving in sample size) and possibly speeding up the time-to-market in drug development.

Clinical Trials as Topic↗
PubMed2000

Re-calculating the sample size in internal pilot study designs with control of the type I error rate.

When designing a clinical trial, there is usually some uncertainty about the variability of the primary outcome variable. This may lead to an unnecessarily high or inadequately low sample size. The internal pilot study approach uses data from patients recruited up to an interim stage to re-estimate the variance and to re-calculate the final sample size accordingly. Previously, simulation studies have shown that this methodology may highly improve the chance to obtain a well-powered trial. However, it also turned out that the type I error rate may be inflated by this procedure. We quantify the maximum excess of the type I error rate for normally distributed outcomes. If strict control of the alpha-level is considered to be an important issue, a method is proposed to achieve this when re-calculating the sample size in internal pilot studies. The characteristics of the power distributions are investigated for various sample size adaptation rules and implications are discussed.

Data Interpretation, Statistical↗
PubMed2000

Modeling the recovery from depressive illness by an exponential model with mixed effects.

In clinical trials of antidepressant treatments, a depression rating score is usually measured at several points of time for each patient. We propose an approach to fit data from this type of clinical trial using an exponential mixed-effects model. Compared to previous proposals, this approach has the advantage that individual recovery curves are fitted rather than curves of means. Furthermore, no artificial fixing of model parameters is needed as in other approaches. The flexibility of the proposed model is shown for various situations. The approach is illustrated by an example from a placebo-controlled study for the treatment of depression with St. John's Wort (Hypericum perforatum).

Antidepressive Agents↗
PubMed1999

Combining different phases in the development of medical treatments within a single trial.

In the development of medical treatments, identification of promising therapies and inference on selected treatments are usually performed in subsequent separate trials. An adaptive two-stage design is proposed for the situation of multiple treatments to be compared with a control, allowing integration of both steps within a single confirmatory trial controlling the multiple level alpha. After the interim analysis, the trial may be terminated early or is continued with a second stage, where the set of treatments may be reduced due to lack of efficacy or to safety problems. The procedure is highly flexible with respect to the distributional assumptions, stopping rules and selection criteria and allows a completely free recalculation of the sample size for the second stage. Simulations show that the method may be substantially more powerful than classical one-stage multiple treatment designs with the same total sample size. As in conventional strategies with a series of separate experiments, a reasonable selection strategy has to be applied in order to prevent proceeding with non-optimal treatments.

Clinical Trials as Topic↗
PubMed1999

Sample size determination for proving equivalence based on the ratio of two means for normally distributed data.

Equivalence trials aim to demonstrate that two treatments do not differ by more than a prespecified clinically irrelevant amount. We consider the problem when equivalence is defined in terms of the ratio of population means and the original (untransformed) data are normally distributed. Application of the intersection-union principle to the test proposed by Sasabuchi results in a two one-sided tests procedure of size alpha. We give the associated 100 (1-2 alpha) per cent confidence interval and derive the exact methods for calculation of power and sample sizes for the parallel group design and the two-period cross-over. We present tables and figures of required sample sizes and achieved power.

Administration, Inhalation↗