The failure of placebo-controlled studies. ECNP Consensus Meeting, September 13, 1997, Vienna. European College of Neuropsychopharmacology

Raising Placebo Efficacy in Antidepressant Trials Across Decades Explained by Small-Study Effects: A Meta-Reanalysis

BACKGROUND

Recent meta-analyses reported placebo response rate in antidepressant trials to be stable since the 1970s. These meta-analyses however were limited in considering only linear time trends, assessed trial-level covariates based on single-model hypothesis testing only, and did not adjust for small-study effects (SSE), a well-known but not yet formally assessed bias in antidepressant trials.

METHODS

This secondary meta-analysis extends previous work by modeling nonlinear time trends, assessing the relative importance of trial-level covariates using a multimodel approach, and rigorously adjusting for SSE. Outcomes were placebo efficacy (continuous), based on the Hamilton Depression Scale, and placebo response rate.

RESULTS

Results suggested that any nonlinear time trends in both placebo efficacy (continuous) and response rate were best explained by SSE. Adjusting for SSE revealed a significant gradual increase in placebo efficacy (continuous) from 1979 to 2014. A similar observation was made for placebo response rate, but did not reach significance due higher susceptibility to SSE. By contrast, trial-level covariates alone were found to be insufficient in explaining time trends.

CONCLUSION

The present findings contribute to the ongoing debate on antidepressant placebo outcomes and highlight the need to adjust for bias introduced by SSE. The results are of clinical relevance because SSE may affect the evaluation of success or failure in antidepressant trials.

Placebos in the era of open-label trials: An update for clinicians

Placebos have been used extensively by vast numbers of physicians, in a majority of clinical trials. Placebo effects involve behavioural, psychological and genetic factors and have been subject to ethical controversies stemming from the use of deception in treating patients. The patient-physician encounter, endogenous pharmacological pathways, personality traits and genetic diversity have all been reported to be key players in placebo responses. In the last decade, a new methodological paradigm of placebo research has emerged, using open-label placebos to investigate their effects which showed promising results for various common medical conditions. In this review, we will summarize the current body of evidence on placebos in clinical practice, with a view to open-label placebo trials in particular. It is our view that future larger-scale randomized blinded open placebo trials will benefit physicians and improve patient outcomes.

Guarding the Gate: Remote Structured Assessments to Enhance Enrollment Precision in Depression Trials

BACKGROUND

Failed treatment trials are common in major depressive disorder and treatment-resistant depression, and remotely performed multifaceted, centralized structured interviews can potentially enhance signal detection by ensuring that enrolled patients meet eligibility criteria.

METHODS

We assessed the use of a specific remote structured interview that validated the diagnosis, level of treatment resistance, and depression severity. The objectives were to (1) assess the rate at which patients who were deemed eligible for participation in trials by site investigators were ineligible, (2) assess the reasons for ineligibility, (3) compare rates of ineligibility between academic and nonacademic sites, (4) compare eligibility between US and non-US sites, and (5) report the placebo response rates in trials utilizing this quality assurance approach, comparing its placebo response rates with those reported in the literature. Methods included a pooled analysis of 9 studies that utilized this methodology (SAFER interviews).

RESULTS

Overall, 15.33% of patients who had been deemed eligible at research sites were not eligible after the structured interviews. The most common reason was that patients did not meet the study requirements for level of treatment resistance. Pass rates were significantly higher at non-US compared with US sites (94.6% vs 83.3%, respectively; P < 0.001). There was not a significant difference between academic and nonacademic sites (87.8% vs 82.4%; P = 0.08). Placebo response rates were 13.0% to 27.3%, below the 30% to 40% average in antidepressant clinical trials, suggesting a benefit of the quality assurance provided by these interviews.

CONCLUSIONS

The use of a remotely structured interview by experienced clinical researchers was feasible and possibly contributed to lower-than-average placebo response rates. The difference between US and non-US sites should be the subject of further research.

Placebo response rates in antidepressant trials: a systematic review of published and unpublished double-blind randomised controlled studies

BACKGROUND

Previous studies have shown that placebo response rates in antidepressant trials have been increasing since the 1970s. However, these studies have been based on outdated or limited datasets and have used inappropriate statistical methods. We did a systematic review of placebo-controlled randomised controlled trials of antidepressants to examine associations between placebo-response rates and study and patient characteristics.

METHODS

In this systematic review, we searched for published and unpublished double-blind randomised placebo-controlled trials of first-generation and second-generation antidepressants for acute treatment of major depression in adults (update: Jan 8, 2016). The log-transformed proportions of placebo response, defined as 50% or greater reduction in depression severity score from baseline, were meta-analytically synthesised for each year. We then looked for a structural break point in the secular changes in these characteristics through the years and examined the influence of the study year and other trial and patient characteristics on the response rates through meta-regression.

FINDINGS

We identified 252 placebo-controlled trials (26 324 patients on placebo) done between 1978 and 2015. There was a structural break in 1991, and since then, the average placebo response rates in antidepressant trials have remained constant in the range between 35% and 40% (relative risk [RR] 1·00, 95% CI 0·97-1·03, p=0·99, for every 5-year increase). The length of the study and the number of study centres were significant factors (RR 1·03, 95% CI 1·01-1·05 for 1 more week in trial length; 1·32, 1·11-1·57 for multicentre vs single-centre trials).

INTERPRETATION

Contrary to the widely held belief, the average placebo response rates in antidepressant trials have been stable for more than 25 years. This new evidence should have an effect on the interpretation of the scientific literature and the future of psychopharmacology, both from a clinical and methodological point of view.

FUNDING

Japan Society for Promotion of Science, Great Britain Sasakawa Foundation.

Manipulating the Placebo Response in Experimental Pain by Altering Doctor's Performance Style

Background: Performance is paramount in traditional healing rituals. From a Western perspective, such performative behavior can be understood principally as inducing patients’ faith in the performer’s supernatural healing powers and effecting positive changes through the same mechanisms attributed to the placebo response, which is defined as improvement of clinical outcome in individuals receiving inactive treatment. Here we examined the possibility of using theatrical performance tools, including stage directions and scripting, to reproducibly manipulate the style and content of a simulated doctor–patient encounter and influence the placebo response in experimental pain.

Methods: A total of 122 healthy volunteers (18–45 years, 76 men) exposed to experimental pain (the cold pressor test) were assessed for pain threshold and tolerance before and after receiving a placebo cream from a “doctor” impersonated by a trained actor. The actor alternated between two distinct scripts and stage directions, i.e., performance styles created by a theater director/playwright, one emulating a standard doctor–patient encounter (scenario A) and the other emphasizing attentiveness and strong suggestion, elements also present in ritual healing (scenario B). The placebo response size was calculated as the %difference in pain threshold and tolerance after exposure relative to baseline. In addition, subjects demonstrating a ≥30% increase in pain threshold or tolerance relative to baseline were defined as responders. Each encounter was videotaped in its entirety.

Results: Inspection of the videotapes confirmed the reproducibility and consistency of the distinct scenarios enacted by the “doctor”-performer. Furthermore, scenario B resulted in a significant increase in pain threshold relative to scenario A. Interestingly, this increase derived from the placebo responder subgroup; as shown by two-way analysis of variance (performance style, F = 4.30; p = 0.040; η² = 0.035; style × responder status interaction term, F = 5.21; p = 0.024) followed by post hoc analysis showing a ∼60% increase in pain threshold in responders exposed to scenario B (p = 0.020).

Conclusion: These results support the hypothesis that structured manipulation of physician’s verbal and non-verbal performance, designed to build rapport and increase faith in treatment, is feasible and may have a significant beneficial effect on the size of the response to placebo analgesia. They also demonstrate that subjects, who are not susceptible to placebo, are also not susceptible to performance style.

Placebo Response in a Patient with Chronic Migraine and Ergotic Overuse

Facilitation of nociceptive systems has been implicated in Chronic-Migraine pathogenesis. Daily consumption of medication may be a contributing factor. The patient was male, aged 76 years, with history of migraine without aura. Six years ago, he presented with a mild-moderate daily pulsating headache. He was overusing analgesics and ergotamine. After withdrawing, the patient started a non-pulsating headache, diffuse and constant. During follow up, he was refractive to several symptomatic and prophylactic treatments. When we treated him with placebo capsules, the headache responded very well. At first, pain-relief occurred for 6 h and progressively, extended. Two years later, when our patient started to use transdermal patches of fentanyl for treatment of a complex regional pain syndrome type 1, his headache did not improve. Patient has maintained prolonged response to placebo. Actually, he is pain-free for 2-3 days with 1 placebo capsule. We discuss mechanisms of chronic-migraine, drug-overuse, drug-induced headache and placebo addiction. Powerful psychological mechanisms could determine response to placebo in this patient.

Fewer study participants needed to demonstrate superior antidepressant efficacy when using the Hamilton melancholia subscale (HAM-D₆) as outcome measure

BACKGROUND

In the development of new antidepressant treatments, the failed study has unfortunately become a prevalent problem. The number of failed studies could probably be reduced significantly by applying more informative outcome measures. Previous studies have indicated that the 6-item melancholia subscale (HAM-D6) of the 17-item Hamilton Depression Rating Scale (HAM-D17) may be more informative than other scales, due to its superior psychometric properties. In the present study we investigated whether the HAM-D6 had higher informativeness than the HAM-D17 based on data from a randomized placebo-controlled trial (RCT) testing the effect of erythropoietin (EPO) as augmentation therapy in patients with treatment-resistant depression.

METHODS

We assessed the scalability (Mokken analysis of unidimensionality), responsiveness (item responsiveness analysis) and ability to show drug-placebo separation (estimation of sample size needed to detect statistically significant difference between EPO and placebo) of the HAM-D6 and the HAM-D17.

RESULTS

The HAM-D6 demonstrated higher scalability, higher responsiveness, and better drug-placebo separation compared to the HAM-D17. As a consequence, only 39 participants per group would be required to detect a statistically significant difference between EPO and placebo when using the HAM-D6 as outcome measure, whereas the required group size for HAM-D17 would be 146 participants.

LIMITATIONS

The EPO RCT was not originally designed to investigate the research questions addressed in this study.

CONCLUSIONS

Both for ethical and financial reasons it is of interest to minimize the number of participants in clinical trials. Therefore, we suggest employing the HAM-D6 as outcome measure in clinical trials of depression.

Placebo response in antipsychotic trials of patients with acute mania: Results of an individual patient data meta-analysis

We examined the role of placebo response in acute mania trials. Specifically, whether placebo response: (1) predicts treatment effect, (2) can be predicted by patient and study characteristics, and (3) can be predicted by a parsimonious model. We performed a meta-analysis of individual patient data from 10 registration studies (n=1019) for the indication acute manic episode of bipolar disorder. We assessed the effect of 14 determinants on placebo response. Primary outcome measures were mean symptom change score (MCS) on the Young Mania Rating Scale (YMRS) and response rate (RR), defined as ≥ 50% YMRS symptom improvement from baseline to endpoint. The overall placebo response was 8.5 points improvement on the YMRS (=27.9%) with a RR of 32.8%. Placebo response was significantly associated with the overall treatment response. Five determinants significantly (p<0.05) predicted the placebo response. The multivariate prediction model, which consisted of baseline severity, psychotic features at baseline, number of geographic regions, and region, explained 10.4% and 5.5% of the variance in MSC and RR, respectively. Our findings showed that the placebo response in efficacy trials of antipsychotics for acute mania is substantial and an important determinant of treatment effect. Placebo response is influenced by patient characteristics (illness severity and presence of psychotic features) and by study characteristics (study year, number of geographic regions and region). However, the prediction model could only explain the placebo response to a limited extent. Therefore, limiting trials to certain patients in certain geographic regions seems not a viable strategy to improve assay sensitivity.

Placebo, prozac and PLoS: significant lessons for psychopharmacology

Kirsch et al. (2008, Initial severity and antidepressant benefits: a meta-analysis of data submitted to the Food and Drug Administration. PLoS Med 5: e45), conducted a meta-analysis of data from 35 placebo controlled trials of four newer antidepressants. They concluded that while these drugs are statistically significantly superior to placebo in acute depression, the benefits are unlikely to be clinically significant. This paper has attracted much attention and debate in both academic journals and the popular media. In this critique, we argue that Kirsch et al.'s is a flawed analysis which relies upon unusual statistical techniques biased against antidepressants. We present results showing that re-analysing the same data using more appropriate methods leads to substantially different conclusions. However, we also believe that psychopharmacology has lessons to learn from the Kirsch et al. paper. We discuss issues surrounding the interpretation of clinical trials of antidepressants, including the difficulties of extrapolating from randomized controlled trials to the clinic, and the question of failed trials. We call for more research to establish the effectiveness of antidepressants in clinically relevant populations under naturalistic conditions, for example, in relapse prevention, in patients with co-morbidities, and in primary care settings.

Placebo and nocebo effects in randomized double-blind clinical trials of agents for the therapy for fatigue in patients with advanced cancer

BACKGROUND

A significant response to placebo in randomized controlled trials of treatments for cancer-related fatigue (CRF) had been reported. A retrospective study was conducted to determine the frequency and predictors of response to placebo effect and nocebo effects in patients with CRF treated in those trials.

METHODS

The records of 105 patients who received placebo in 2 previous randomized clinical trials conducted by this group were reviewed. The proportion of patients who demonstrated clinical response to fatigue, defined as an increase in Functional Assessment of Chronic Illness Therapy-Fatigue score of > or = 7 from baseline to Day 8, and the proportion of patients with a nocebo effect, defined as those reporting >2 side effects, were determined. Baseline patient characteristics and symptoms recorded using the Edmonton Symptom Assessment Scale (ESAS) were analyzed to determine their association with placebo and nocebo effects.

RESULTS

Fifty-nine (56%) patients had a placebo response. Worse baseline anxiety and well-being subscale score (univariate) and well-being (multivariate) were significantly associated with placebo response. Commonly reported side effects were insomnia (79%), anorexia (53%), nausea (38%), and restlessness (34%). Multivariate analysis indicated that worse baseline (ESAS) sleep, appetite, and nausea were associated with increased reporting of the corresponding side effects.

CONCLUSIONS

Greater than half of advanced cancer patients enrolled in CRF trials had a placebo response. Worse baseline physical well-being score was associated with placebo response. Patients experiencing specific symptoms at baseline were more likely to report these as side effects of the medication. These findings should be considered in the design of future CRF trials.

Reconsidering the placebo response from a broad anthropological perspective

This paper considers how the full range of human experience may catalyze a placebo response. The placebo effect has been characterized as something to control in clinical research, something to cultivate in clinical practice and something present in all healing encounters. We examine domains in which the term 'placebo' is used in discourse: clinical research, clinical practice, media representations of treatment efficacy and lay interpretations of placebo--an underresearched topic. We briefly review major theoretical frameworks proposed to explain the placebo effect: classical conditioning, expectancy, the therapeutic relationship and sociocultural 'meaning.' As a corrective to what we see as an overemphasis on conscious cognitive approaches to understanding placebo, we reorient the discussion to argue that direct embodied experience may take precedence over meaning-making in the healing encounter. As an example, we examine the neurobiology of rehearsing or visualizing wellness as a mode of directly (performatively) producing an outcome often dismissed as a 'placebo response.' Given body/mind/emotional resonance, we suggest that the placebo response is an evolutionarily adaptive trait and part of healing mechanisms operating across many levels--from genetic and cellular to social and cultural.

Predicting response to opiate antagonists and placebo in the treatment of pathological gambling

RATIONALE

Although opiate antagonists have shown promise in the treatment of pathological gambling (PG), individual responses vary. No studies have systematically examined predictors of medication treatment outcome in PG. Understanding clinical variables related to treatment outcome should help generate treatment algorithms for PG.

OBJECTIVE

We sought to identify clinical variables associated with treatment outcome in PG subjects receiving opiate antagonists.

MATERIALS AND METHODS

Two hundred eighty-four subjects [137 (48.2%) women] with DSM-IV PG were treated in one of two double-blind placebo-controlled trials (16 weeks of nalmefene or 18 weeks of naltrexone). Gambling severity was assessed with the Yale Brown Obsessive Compulsive Scale Modified for Pathological Gambling (PG-YBOCS) with positive response defined as > or =35% reduction in PG-YBOCS score for at least 1 month by study endpoint. Depression, anxiety, and psychosocial functioning were included in stepwise logistic regression analyses designed to identify clinical factors independently associated with treatment response.

RESULTS

The clinical variable most strongly associated with a positive response to an opiate antagonist was a positive family history of alcoholism (p = 0.006). Among individuals receiving higher doses of opiate antagonists (i.e., nalmefene 50 or 100 mg/day or naltrexone 100 or 150 mg/day), intensity of gambling urges (PG-YBOCS urge subscale) was associated with a positive response on a trend level (p = 0.036). Among individuals receiving placebo, younger age was associated, on a trend level, with positive treatment outcome (p = 0.012).

CONCLUSIONS

A family history of alcoholism appears to predict response to an opiate antagonist in PG. Future research is needed to identify specific factors (e.g., genetic) mediating favorable responses.

Continuation and long-term maintenance treatment with Hypericum extract WS 5570 after recovery from an acute episode of moderate depression--a double-blind, randomized, placebo controlled long-term trial

The efficacy and safety of Hypericum extract WS 5570 in preventing relapse during 6 months' continuation treatment and 12 months' long-term maintenance treatment after recovery from an episode of recurrent depression were investigated in a double-blind, placebo controlled multicenter trial. Adult out-patients with a recurrent episode of moderate major depression, a 17-item Hamilton Depression Rating Scale (HAMD) total score > or =20 and > or =3 previous episodes in 5 years participated. After 6 weeks of single-blind treatment with 3 x 300 mg/day WS 5570 patients with score < or =2 on item 'Improvement' of the Clinical Global Impressions (CGI) scale and a HAMD total score decrease > or =50% versus baseline were randomized to 3 x 300 mg/day WS 5570 or placebo for 26 weeks. 426 patients were evaluated for efficacy. Relapse rates during continuation treatment were 51/282 (18.1%) for WS 5570 and 37/144 (25.7%) for placebo. Average time to relapse was 177+/-2.8 and 163+/-4.4 days for WS 5570 and placebo, respectively (time-to-event analysis; p=0.034; alpha=0.025 one-sided). Patients treated with WS 5570 showed more favorable HAMD and Beck Depression Inventory time courses and greater over-all improvement (CGI) than those randomized to placebo. In long-term maintenance treatment a pronounced prophylactic effect of WS 5570 was observed in patients with an early onset of depression as well as in those with a high degree of chronicity. Adverse event rates under WS 5570 were comparable to placebo. WS 5570 showed a beneficial effect in preventing relapse after recovery from acute depression. Tolerability in continuation and long-term maintenance treatment was on the placebo level.

Evaluation of treatment response in depression studies using a Bayesian parametric cure rate model

Efficacy trials with antidepressant drugs often fail to show significant treatment effect even though efficacious treatments are investigated. This failure can, amongst other factors, be attributed to the lack of sensitivity of the statistical method as well as of the endpoints to pharmacological activity. For regulatory purposes the most widely used efficacy endpoint is still the mean change in HAM-D score at the end of the study, despite evidence from literature showing that the HAM-D scale might not be a sensitive tool to assess drug effect and that changes from baseline at the end of treatment may not reflect the extent of response. In the current study, we evaluate the prospect of applying a Bayesian parametric cure rate model (CRM) to analyse antidepressant effect in efficacy trials with paroxetine. The model is based on a survival approach, which allows for a fraction of surviving patients indefinitely after completion of treatment. Data was extracted from GlaxoSmithKline's clinical databases. Response was defined as a 50% change from baseline HAM-D at any assessment time after start of therapy. Survival times were described by a log-normal distribution and drug effect was parameterised as a covariate on the fraction of non-responders. The model was able to fit the data from different studies accurately and results show that response to treatment does not lag for two weeks, as is mythically believed. In conclusion, we demonstrate how parameterisation of a survival model can be used to characterise treatment response in depression trials. The method contrasts with the long-established snapshot on changes from baseline, as it incorporates the time course of response throughout treatment.

Genomics and the future of pharmacotherapy in psychiatry

Pharmacogenetic studies of psychotropic drug response have focused on determining the relationship between variation in specific candidate genes and the positive and adverse effects of drug treatment. Preliminary evidence exists for a significant relationship between a promoter region polymorphism in the serotonin transporter gene and antidepressant response, as well as for associations between candidate neurotransmitter receptor genes and second generation antipsychotic drug response. More recent work in schizophrenia has focused on the use of first episode, antipsychotic naïve subjects, which may provide greater study power as suggested by studies examining dopamine receptor genetic variation and clinical response measures. An emerging body of literature suggests that pharmacogenetic strategies may be especially useful in the prediction of drug-induced adverse effects, in particular for the important side effect of antipsychotic-induced weight gain. New developments in genomics, including whole genome genotyping approaches and comprehensive information on genomic variation across populations, coupled with large-scale clinical trials in which DNA collection is routine, now provide the impetus for a next generation of pharmacogenetic studies. These increasingly comprehensive approaches should provide informative data on the genes associated with psychotropic drug response, a critical step towards the ultimate goal of 'personalized' medicine.

Drug Treatment in Juvenile Depression - Is St. John's Wort a Safe and Effective Alternative?

Analyses of juvenile depression studies with long established anti-depressants (tricyclic anti-depressants) have revealed discouragingly little benefit, while side effects have been profound. Modern anti-depressants like selective serotonin reuptake inhibitors seemed to solve part of this problem until they were found to be associated with an increased risk of suicidal attempts and ideation, hostile behaviour and self-harm, while meta-analyses have revealed only marginal therapeutic effects for the majority. Actually, no drug is unequivocally accepted as the gold-standard for young depressive patients. St. John's Wort (SJW) has been traditionally used in Europe to treat symptoms associated with juvenile depression. Close to 50 clinical studies performed over the last two decades have been presented as evidence that standardized SJW preparations are equally effective as synthetic anti-depressants in the treatment of mild to moderate depression in adults. Tolerability is excellent, but some relevant drug interactions have to be considered. Today, SJW is by far the most frequently prescribed medication for child and adolescent depression in Germany. Some pilot and observational studies from Germany, Canada and the US have delivered promising results. However, randomised controlled trials amongst this age group have yet to be carried out and are long overdue.

The future of selective serotonin reuptake inhibitors (SSRIs) in psychiatric treatment

Selective serotonin reuptake inhibitors (SSRIs) are widely prescribed and widely regarded as a first-line treatment for depression. Yet, a growing body of evidence indicates that these agents are only moderately more effective than placebo in treating major depressive disorder. In recent years, it has been debated whether SSRIs offer any clinically meaningful advantage over placebos. As part of this debate, it has been argued that these agents are first-line treatments for some forms of depression but not necessarily for others. The present paper examines two hypotheses that are central to these issues. The first hypothesis is that SSRIs are more effective than placebo for some types of depression but not for others. The second is that SSRIs are more effective than psychotherapies for some types of depression than others. A review of the empirical literature reveals three main classifications of depression that are relevant to the first hypothesis: (a) more vs. less severe depression, (b) melancholic vs. non-melancholic depression, and (c) depression defined according to associated genetic factors (particularly the long vs. short allele of the serotonin transporter gene promoter). There is no strong or consistent support for (a) or (b). There is, however, emerging and consistent evidence for (c), and so the first hypothesis is tentatively supported, but only for (c). Most of the empirical evidence does not support the second hypothesis. Psychotherapies (cognitive-behavioral and interpersonal therapies) and SSRIs generally have equivalent efficacy, regardless of the severity of depression. The research literature also suggests a third hypothesis that remains to be evaluated: that SSRIs are more effective for treating anxiety disorders (and possibly other disorders) than they are for treating depression. If that hypothesis is supported by subsequent research, then the future of SSRIs may lie largely in the treatment of anxiety disorders, and in the management of particular subtypes of depression.

Assessment of a method to expel intraperitoneal gas after gynecologic laparoscopy

STUDY OBJECTIVE

To assess a method using instillation of saline to expel all residual intraperitoneal CO2 after laparoscopy. If successful, this would enable clinicians to use radiography as a simple diagnostic test to detect bowel perforation following laparoscopic surgery.

DESIGN

Cohort study (Canadian Task Force classification II-2).

SETTING

Department of Endo-Gynecology, Royal Hospital for Women, Sydney, Australia.

PATIENTS

Thirty women undergoing elective gynecologic laparoscopic surgery.

INTERVENTIONS

At completion of surgery, the patient remained in maximum head- down position as the abdomen was filled with up to 1 L of normal saline. The suprapubic port remained open to allow the CO2 to escape as it was displaced by the saline. Closure of abdominal ports was completed in routine manner. Erect upper abdominal radiographs were taken 24 hours after surgery, and measurements of any subdiaphragmatic gas were recorded. If gas was evident at 24 hours, a repeat radiograph was performed at 48 hours.

MEASUREMENTS AND MAIN RESULTS

Of the 30 patients recruited, four did not complete the study protocol. There was evidence of subdiaphragmatic gas in 25 (96%) of 26 patients on the radiograph taken 24 hours postsurgery. The median volume of gas was 12.9 mL (range 0-2003 mL; IQ range 2.0-144 mL). Of the patients that had a second radiograph, 76% still had subdiaphragmatic gas present.

CONCLUSION

This method for displacement of residual intraperitoneal gas at the end of laparoscopy does not appear to be effective.

Comparing the effects of antidepressants: consensus guidelines for evaluating quantitative reviews of antidepressant efficacy

With increasing numbers of treatment options available for patients with major depression over the last decade and the growing body of evidence describing their efficacy and safety, clinicians often find it difficult to determine the best and most appropriate evidence-based treatment for each patient. Systematic reviews utilizing statistical methods that synthesize and evaluate data from a number of studies have become increasingly more available over the past decade. We review major findings and lessons learned from salient examples of quantitative analyses of antidepressant research and provide recommendations for meta-analysts, journal and grant reviewers, and research 'consumers' (ie, clinicians) for conducting, reporting, and evaluating such analyses.

Hypericum extract LI 160 and fluoxetine in mild to moderate depression: a randomized, placebo-controlled multi-center study in outpatients

Efficacy and tolerability of Hypericum LI 160 was compared to fluoxetine and placebo in mild to moderate Major Depression (DSM-IV) in a 4-week randomized, double-blind trial. One hundred and sixty-three outpatients from 15 general practitioner centers received either 900 mg Hypericum LI 160, 20 mg fluoxetine, or placebo daily. Amelioration was measured by the Hamilton and the Montgomery-Asberg Depression scales. Response and remission rates and global ratings by investigators and patients were measured. Adverse event reports, laboratory screening, vital signs, physical exams and ECG were collected. No significant differences could be observed regarding efficacy measures except for remission rate (Hypericum 24%; fluoxetine 28%; placebo 7 %). Hypericum was significantly better tolerated than fluoxetine. Hypericum LI 160 or fluoxetine were not more effective in short-term treatment in mild to moderate depression than placebo.

Treatment of somatoform disorders with St. John's wort: a randomized, double-blind and placebo-controlled trial

OBJECTIVE

To investigate efficacy and safety of St. John's wort (SJW) LI 160 in somatoform disorders.

METHODS

In a prospective, randomized, placebo-controlled, and double-blind parallel group study, 184 outpatients with somatization disorder (ICD-10 F45.0), undifferentiated somatoform disorder (F45.1), and somatoform autonomic dysfunction (F45.3), but not major depression, received either 300 mg of SJW extract LI 160 twice daily or matching placebo for 6 weeks. Six outcome measures were evaluated as a combined measure by means of the Wei Lachin test: Somatoform Disorders Screening Instrument--7 days (SOMS-7), somatic subscore of the HAMA, somatic subscore of the SCL-90-R, subscores "improvement" and "efficacy" of the CGI, and the global judgment of efficacy by the patient.

RESULTS

In the intention to treat population (N=173), for each of the six primary efficacy measures as well as for the combined test, statistically significant medium to large-sized superiority of SJW treatment over placebo was demonstrated (p <.0001). Of the SJW patients, 45.4% were classified as responders compared with 20.9% with placebo (p =.0006). Tolerability of SJW treatment was equivalent to placebo.

CONCLUSIONS

Administration of 600 mg of SJW extract LI 160 daily is effective and safe in the treatment of somatoform disorders, thereby confirming results from a previous study.

Do equivalent doses of escitalopram and citalopram have similar efficacy? A pooled analysis of two positive placebo-controlled studies in major depressive disorder

Escitalopram is the S-enantiomer of citalopram. In this study, we compared the efficacy of equivalent dosages of escitalopram and citalopram in the treatment of moderate to severe major depressive disorder (MDD), based on data from two, pooled, randomized, double-blind, placebo-controlled studies of escitalopram in which citalopram was the active reference. The primary efficacy parameter was the mean change from baseline in the Montgomery Asberg Depression Rating Scale (MADRS) total score. Significant differences in favour of escitalopram were observed for the MADRS [P<0.05, observed cases (OC)/last observation carried forward (LOCF)] and Clinical Global Improvement-Severity of Illness scores (CGI-S; P<0.05, OC/LOCF). Escitalopram separated from placebo at week 1 on the primary efficacy parameter, whereas citalopram first separated from placebo at week 6. An analysis of time to response showed that escitalopram-treated patients responded significantly faster to treatment than citalopram-treated patients (P<0.01). More patients responded to and achieved remission with escitalopram than to citalopram (P<0.05, OC). The HAMD scale was only used in the fixed-dose study, where escitalopram-treated patients had a significant reduction in HAMD-17 total score at week 8 compared to citalopram-treated patients (P<0.05, OC/LOCF). In the pooled subpopulation of severely ill patients (MADRS> or = 30), escitalopram-treated patients showed greater improvement than citalopram-treated patients (P<0.05, LOCF/OC). Escitalopram showed consistently superior efficacy compared to citalopram in the treatment of moderate to severe MDD on all efficacy parameters, and was similarly well tolerated.

Implementing A Research Agenda for Complementary and Alternative Medicine

Complementary and alternative medicine (CAM) consists of diverse clinical interventions that are practiced because of their popularity rather than the prior demonstration of safety and efficacy required for conventional agents. CAM therapies can be grouped into five categories: biologically based therapies, manipulative and body-based interventions, mind-body interventions, "energy" therapies, and alternative medical systems. The present evidence that individual CAM interventions are efficacious is largely anecdotal, but hundreds of small trials have yielded positive results. For a few modalities, existing data are either very encouraging or else sufficient to conclude that they are ineffective. CAM interventions are presumed to be safe, yet they may not be, particularly in the case of botanical agents with inherent toxicities, significant drug interactions, or potent adulterants. The public health questions regarding CAM can only be addressed through a research agenda that defines which interventions have favorable therapeutic indices. Implementation of this agenda involves adequate characterization and standardization of the product or practice, with rigorous investigation to demonstrate its safety, mechanism of action, and efficacy.

Treatment of anxiety, tension and restlessness states with Kava special extract WS 1490 in general practice: a randomized placebo-controlled double-blind multicenter trial

The efficacy and tolerability of 150 mg/d Kava special extract WS 1490 were investigated in a randomized, placebo-controlled, double-blind multicenter study in patients suffering from neurotic anxiety (DSM-III-R diagnoses 300.02, 300.22, 300.23, 300.29, or 309.24). 141 adult, male and female out-patients received 3 x 1 capsule of 50 mg/d WS 1490 or placebo for four weeks, followed by two weeks of observation without study-specific treatment. During randomized treatment the total score of the Anxiety Status Inventory (ASI) observer rating scale showed more pronounced decreases in the WS 1490 group than in the placebo group. Although a treatment group comparison of the post-treatment ASI scores was not significant (p > 0.05), an exploratory analysis of variance across the differences between treatment end and baseline, with center as a second factor, showed superiority of the herbal extract over placebo (p < 0.01, two-sided). 73% of the patients treated with WS 1490 exhibited ASI score decreases > 5 points versus baseline, compared to 56% for placebo. Significant advantages for WS 1490 were also evident in a structured well-being self-rating scale (Bf-S) and the Clinical Global Impressions (CGI), while the Erlangen Anxiety, Tension and Aggression Scale (EAAS) and the Brief Test of Personality Structure (KEPS) showed only minor treatment group differences. Although the results show consistent advantages for WS 1490 over placebo in several psychiatric scales and indicate significant improvements in the patients' general well-being, the differences versus placebo were not as large as in previous trials which employed 300 mg/d of the same extract. WS 1490 was well tolerated, with no influence on liver function tests and only one trivial adverse event (tiredness) attributable to the study drug.

Affective and anxiety comorbidity in post-traumatic stress disorder treatment trials of sertraline

Comorbidity of mood and anxiety disorders is common in patients suffering from post-traumatic stress disorder (PTSD). The current study evaluated the efficacy and tolerability of sertraline in a subgroup of PTSD patients suffering from anxiety or depression comorbidity. Two multicenter, 12-week, double-blind, flexible-dose US studies of adult outpatients from the general population with a DSM-III-R diagnosis of PTSD evaluated the safety and efficacy of sertraline (50 to 200 mg/d) compared to placebo in the treatment of PTSD. The total severity score of the Clinician-Administered PTSD Scale (CAPS-2) and the Davidson Trauma Scale (DTS) were used to examine the effect of comorbidity on treatment outcome. Among the combined 395 subjects enrolled in the two trials, 32.9% had a comorbid depressive diagnosis (no anxiety diagnosis), 6.3% had a comorbid anxiety disorder diagnosis (no depression), 11.4% had both a depression and anxiety disorder diagnosis, and 49.4% had no comorbidity. The correlation, at baseline, between Hamilton Depression Rating Scale (HAM-D) total score and the three CAPS-2 clusters was 0.37 for the re-experiencing/intrusion cluster, 0.52 for the avoidance/numbing cluster, and 0.45 for the hyperarousal cluster. Patients suffering from PTSD complicated by a current diagnosis of both depression and an anxiety disorder showed the highest baseline CAPS-2 cluster score severity. Patients treated with sertraline improved significantly (P <.05) compared to placebo on both the CAPS-2 and DTS whether or not they had a comorbid depressive or anxiety disorder. Sertraline was well tolerated. The presence of comorbidity was associated with a modest and mostly nonspecific increase in the side effect burden of approximately 10% to 20% on both study treatments. Patients suffering from dual depression and anxiety disorder comorbidity benefited from somewhat higher doses (147 mg v 125 mg; P =.08). Similarly, the presence of dual comorbidity resulted in a modest but nonsignificant increase in the mean time to response from 4.5 weeks to 5.5 weeks. We conclude that sertraline (50 to 200 mg/d) is effective and well tolerated in the treatment of PTSD for patients suffering from a current, comorbid depressive or anxiety disorders.

Determination of the dose of agomelatine, a melatoninergic agonist and selective 5-HT(2C) antagonist, in the treatment of major depressive disorder: a placebo-controlled dose range study

Agomelatine (S 20098) has a unique and new pharmacological profile. It is a melatoninergic agonist and selective antagonist of 5-HT2C receptors, and has been shown to be active in several animal models of depression. The aim of this study was to determine the active dose of agomelatine in the treatment of major depressive disorder (DSM-IV criteria). The methodology used was a conventional double-blind design comparing three different doses of agomelatine (1, 5 and 25 mg once a day) with placebo over an 8-week treatment period. Paroxetine was used as the study validator. Seven hundred and eleven patients with a baseline mean score of 27.4 on the 17-item Hamilton Rating Scale for Depression (HAM-D) were included. On the pivotal analysis, the mean final HAM-D total score (Full Analysis Set LOCF) demonstrated agomelatine 25 mg to be statistically more effective than placebo. This was confirmed by other analyses and criteria (responders, remission, subpopulation of severely depressed patients, Montgomery-Asberg Depression Rating Scale, Clinical Global Impression-Severity of Illness). Agomelatine 25 mg alleviated the anxiety associated with depression, as measured on Hamilton Anxiety Scale. Paroxetine was found to be effective on pivotal analysis and most of the secondary criteria used to validate the study methodology and population. Agomelatine, whatever the dose, showed good acceptability with a side-effects profile close to that of placebo. In conclusion, this study demonstrates that agomelatine is efficient in the treatment of major depressive disorder and that 25 mg is the target dose.

Efficacy and safety of amisulpride 50 mg versus paroxetine 20 mg in major depression: a randomized, double-blind, parallel group study

The efficacy of amisulpride in depressive disorders has been demonstrated in dysthymia and in double depression. Limited data are available in major depression. A randomized, double-blind, parallel group, multicentre study was set up to compare the efficacy and tolerability of amisulpride (50 mg o.d.) and paroxetine (20 mg o.d.) for 8 weeks in 272 patients with major depression (DSM-IV and baseline Hamilton Depression Rating Scale (HAMD) score > or = 18). The study was designed as a non-inferiority trial based on the proportion of responders (> or = 50% decrease in HAMD total score) at end-point, with a maximal allowable difference of 15%; secondary end-points included HAMD total and cluster scores, Montgomery and Asberg Depression Rating Scale score and responders rates and Clinical Global Impression improvement. The tolerability evaluation was based on incidence of adverse events and routine laboratory tests. The results did not disclose statistically significant differences between treatments, although the hypothesis of an efficacy difference between the two treatments within the set limit at day 56 could not be accepted. The issue of non-inferiority trials is discussed.

The double-blind variable placebo lead-in period: results from two antidepressant clinical trials

The 1-week single-blind placebo lead-in has long been a standard in double-blind psychopharmacology clinical trials. Although a lead-in period is often necessary (e.g., to receive laboratory results before randomization), some authors have demonstrated that the standard single-blind placebo lead-in's performance was similar to having a lead-in in which placebo was not administered. The single-blind placebo lead-in did not decrease postrandomization placebo response, nor did it increase drug-placebo differences. To eliminate a higher percentage of placebo responders before randomization and to reduce potential biases in baseline ratings, the authors designed and implemented two depression studies with a double-blind variable placebo lead-in period. In these designs, both the patients and personnel at the investigative sites were blinded to the length of the placebo lead-in period and the start of the active treatment period. Approximately 28% of the patients in the double-blind placebo lead-in studies met criteria to be placebo lead-in responders, as compared with fewer than 10% from two single-blind placebo lead-in studies conducted in a similar time frame. Although all patients continued in the study (including placebo lead-in responders), the primary efficacy analysis prospectively excluded double-blind placebo lead-in responders. Analysis of postrandomization changes revealed that double-blind placebo lead-in responders, even when continuing to receive placebo treatment, maintained their response. At the study endpoint, these placebo lead-in responders had significantly lower severity scores than their counterparts who were not lead-in responders. The prospective removal of lead-in responders thus resulted in an increase in mean endpoint placebo group severity scores. This resulted in an increased drug-placebo treatment difference in one of the two studies but had no effect on the treatment difference in the other study.

Faster response on amisulpride 50 mg versus sertraline 50-100 mg in patients with dysthymia or double depression: a randomized, double-blind, parallel group study

Amisulpride (50 mg o.d.) was compared with sertraline (50-100 mg o.d.) for 12 weeks in a double-blind, parallel-group study in 313 outpatients with dysthymia (DSM-IV +/- episode of major depression). Full response rate [> or = 50% decrease in Hamilton Depression Rating Scale (HAMD) total score] was higher with amisulpride after 4 weeks (63% versus 50%, P < 0.02) and 8 weeks (82% versus 69%, P < 0.009). Time to initial improvement (> or = 25% decrease in HAMD total score) and to > or = 50% HAMD decrease were significantly shorter with amisulpride (P < 0.0033 and P < 0.0080, respectively). A faster response was also present in the subgroup of patients with pure dysthymia. The improvement in HAMD, Montgomery and Asberg Depression Rating Scale and Social and Occupational Assessment Scale total scores, as well as Clinical Global Impression improvement, was significantly greater with amisulpride after 4 weeks. Both drugs were equally effective at week 12. The tolerability of both drugs was satisfactory. Amisulpride is significantly more effective than sertraline during the first weeks of treatment in dysthymia.

The placebo response in social phobia

The placebo response forms a growing problem in randomized, placebo-controlled clinical trials in psychiatry. Research into the placebo response is on the increase, but remains very limited in relation to social phobia. Together with the dropout rate, the placebo effect is an important factor limiting the discriminative properties of any study. In this study, we reviewed 15 placebo-controlled studies in social phobia, focussing on patients and study characteristics. In social phobia, the placebo effect has turned out to be moderately large and has shown no increase over the past decade. Placebo response was highest in large, multicentred trials and was independent of study duration. No validation for a placebo run-in was found. Taking into account both response to placebo and active drug, as well as dropout rate, the most discriminative results are probably to be expected in a sample of patients who are moderately to severely impaired. More research in the field of the placebo response is needed.

The psychodynamic and pharmacodynamic effects of drugs: a differentiated evaluation of the efficacy of phytotherapy

The therapeutic usefulness of medicines is nowadays usually measured in terms of parameters devised in the artificial surroundings of a double blind clinical trial. The difference between the active drug and the placebo is accepted as being the same as the desired overall effect. Yet, when applied to whole categories of medicines, this yardstick can be misleading, as has become apparent from the discussion which has recently arisen regarding the genuine and the illusory pharmacodynamic effects of synthetic antidepressants. Differentiated analysis of a representative number of placebo-controlled studies has shown that when used for depressive conditions, the psychodynamic components contribute far more to the overall effect than do the pharmacodynamic components. In this respect, modern synthetic antidepressants are no better than Hypericum products of plant origin. Among other things, this means that for depressive states and similar indications, the safety, tolerability and acceptability of a medicine must be given much greater weight than its pharmacodynamic effects as assessed simply by testing against a placebo. The quantification of the two therapeutic components, as can be accomplished by a placebo-controlled drug trial, has revealed that the overall outcome of therapy for various important indications of this kind is attributable predominantly to the psychodynamic component. It may reasonably be assumed that the contribution made by the pharmacodynamic effects to the overall therapeutic response will amount to only about 20-50%. This raises questions regarding the clinical relevance and economic value of placebo-controlled studies. When assessing data on drug efficacy for the purpose of licensing applications, greater attention should be given to this reality.