Clinical trial design in schizophrenia: implications for clinical decisions

Effectiveness, tolerability, and safety of ziprasidone in patients with schizophrenia or schizoaffective disorder: Results of a multi-centre observational trial

Purpose

The ZEISIG study (Ziprasidone Experience in Schizophrenia in Germany/Austria) investigated the effectiveness of ziprasidone as measured by discontinuation rates and mean changes of the BPRS total. Secondary objectives included quality of life, subjective well-being, tolerability, and safety.

Subjects and methods

Two hundred and seventy-six subjects with schizophrenia and schizoaffective disorder were treated within an open-label, 12-week, prospective, flexible-dose observational trial of ziprasidone (40–160 mg/day). Baseline and outcome assessments mainly included Brief Psychiatric Rating Scale (BPRS), Clinical Global Impressions Scale (CGI), Short-Form 12 (SF-12), and Subjective Well-being under Neuroleptic treatment (SWN-K).

Results

Study discontinuation due to any cause was evident in 58% of subjects, most of them within the first 4 weeks after study initiation. In study completers, ziprasidone was associated with improvements in BPRS total (44.8 to 33.6; p < 0.001), CGI, SF-12, and SWN-K total scores (80.5 to 89.5). Ziprasidone was related to reduction of weight, fasting glucose, and serum lipids. No cardiovascular adverse event or significant increase of the QTc interval was observed.

Discussion and conclusion

Approximately 60% of subjects discontinued ziprasidone prematurely, probably related to an initial and overall underdose. The present study confirmed previous tolerability and safety data of ziprasidone as well as results of its effectiveness. Independent from reason to switch, previous antipsychotic class, and severity of illness at baseline, the recommended starting dose of 80 mg/day as well as the maximum treatment dose of 160 mg/day may not be sufficient for a selected subgroup of patients.

Valproate for schizophrenia

BACKGROUND

Many people with schizophrenia do not achieve a satisfactory treatment response with ordinary antipsychotic drug treatment. In these cases, various add-on medications are used, and valproate is one of these.

OBJECTIVES

To examine whether:1. valproate alone is an effective treatment for schizophrenia and schizoaffective psychoses; and2. valproate augmentation of antipsychotic medication is an effective treatment for the same illnesses.

SEARCH METHODS

We searched the Cochrane Schizophrenia Group's Study-Based Register of Trials (July 2002; February 2007; July 2012; March 04, 2016). We also contacted pharmaceutical companies and authors of relevant studies in order to identify further trials.

SELECTION CRITERIA

We included all randomised controlled trials comparing valproate to antipsychotics or to placebo (or no intervention), whether as the sole agent or as an adjunct to antipsychotic medication for the treatment of people with schizophrenia or schizophrenia-like psychoses.

DATA COLLECTION AND ANALYSIS

We independently inspected citations and, where possible, abstracts, ordered papers, and re-inspected and quality-assessed these. At least two review authors independently extracted data. We analysed dichotomous data using risk ratio (RR) and its 95% confidence intervals (CI). We analysed continuous data using mean differences (MD) and their 95% CI. We assessed risk of bias for included studies and used GRADE (Grading of Recommendations Assessment, Development and Evaluation) to create a 'Summary of findings' table.

MAIN RESULTS

The 2012 update search identified 19 further relevant studies, most of which were from China. Thus the review currently includes 26 studies with a total of 2184 participants. All trials examined the effectiveness of valproate as an adjunct to antipsychotics. With the exception of two studies, the studies were small, the participants and personnel were not blinded (neither was outcome assessment), and most were short-term and incompletely reported.For this update we prespecified seven main outcomes of interest: clinical response (clinically significant response, aggression/agitation), leaving the study early (acceptability of treatment, overall tolerability), adverse events (sedation, weight gain) and quality of life.Adding valproate to antipsychotic treatment resulted in more clinically significant response than adding placebo to antipsychotic drugs (14 RCTs, n = 1049, RR 1.31, 95% CI 1.16 to 1.47, I2 = 12%, low-quality evidence). However, this effect was removed after excluding open RCTs in a sensitivity analysis. In terms of acceptability of treatment (measured by the number of participants leaving the study early due to any reason) valproate was just as acceptable as placebo (11 RCTs, n = 951, RR 0.76, 95% CI 0.47 to 1.24, I2 = 55%). Also overall tolerability (measured by the number of participants leaving the study early for adverse events) between valproate and placebo was similar (6 RCTs, n = 974, RR 1.33, 95% CI 0.90 to 1.97, I2 = 0).Participants in the valproate group were found to be less aggressive than the control group based on the Modified Overt Aggression Scale (3 RCTs, n = 186, MD -2.55, 95% CI -3.92 to -1.19, I2 = 82%, very low-quality evidence). Participants receiving valproate more frequently experienced sedation (8 RCTs, n = 770, RR 1.38, 95% CI 1.07 to 1.79, I2 = 0, low-quality evidence) but were no more likely to gain weight than those receiving placebo (4 RCTs, n = 427, RR 1.17, 95% CI 0.76 to 1.82, I2 = 0, low-quality evidence). No study reported on the important outcome of quality of life.

AUTHORS' CONCLUSIONS

There is limited evidence, based on a number of trials, that the augmentation of antipsychotics with valproate may be effective for overall clinical response, and also for specific symptoms, especially in terms of excitement and aggression. However, this evidence was entirely based on open RCTs. Moreover, valproate was associated with a number of adverse events among which sedation and dizziness appeared significantly more frequently than in the control groups. Further randomised studies which are blinded are necessary before any clear recommendation can be made. Ideally these would focus on people with schizophrenia and aggression, on those with treatment-resistant forms of the illness and on those with schizoaffective disorders.

Patient participation in antipsychotic drug choice decisions

Patient inclusion in antipsychotic drug decisions is recommended by international treatment guidelines. For N=300 in patients with schizophrenia, we analysed patients' preferences for inclusion in decisions and physicians' estimates which patients actually participated in drug choice. Path analysis was used to examine the relationships between patients' preferences/actual participation and clinical variables measured. Forty percent of the patients expressed a wish to participate in clinical decisions. Those patients wishing to participate in medical decisions had less insight into the necessity of treatment. Psychiatrists gave better ratings of the doctor-patient relationship to those patients whom they rated as having participated in their drug choice. These patients had more positive attitudes towards antipsychotic medication. There was no relationship between the desire to participate and actual participation in the drug choice. When working with patients exhibiting poor insight and negative drug attitudes, psychiatrists use authoritative decision-making styles despite the patient's desire to participate.

Appraising evidence for intervention effectiveness in early psychosis: conceptual framework and review of evaluation approaches

The literature that is relevant to evaluation of treatment effectiveness is large, scattered and difficult to assemble for appraisal. This scoping review first develops a conceptual framework to help organize the field, and second, uses the framework to appraise early psychosis intervention (EPI) studies. Literature searches were used to identify representative study designs, which were then sorted according to evaluation approach. The groupings provided a conceptual framework upon which a map of the field could be drawn. Key words were cross-checked against definitions in dictionaries of scientific terms and the National Library of Medicine Medical Subject Headings (MeSH) browser. Using the final list of key words as search terms, the EPI evaluation literature was appraised. Experimental studies could be grouped into two classes: efficacy and effectiveness randomized controlled trials. Non-experimental studies could be subgrouped into at least four overlapping categories: clinical epidemiological; health service evaluations; quality assurance studies; and, quasi-experimental assessments of treatment effects. Applying this framework to appraise EPI studies indicated promising evidence for the effectiveness of EPI irrespective of study design type, and a clearer picture of where future evaluation efforts should be focused. Reliance on clinical trials alone will restrict the type of information that can inform clinical practice. There is convergent evidence for the benefits of specialized EPI service functions across a range of study designs. Greater investment in health services research and quality assurance approaches in evaluating EPI effectiveness should be made, which will involve scaling up of study sizes and development of an EPI programme fidelity rating template. The degree of complexity of the evaluation field suggests that greater focus on research methodology in the training of Australasian psychiatrists is urgently needed.

Conceptual and methodological issues in the design of clinical trials of antipsychotics for the treatment of schizophrenia

Schizophrenia is one of the most severe and disabling psychiatric disorders. Antipsychotic drugs offer considerable benefits in controlling symptoms and preventing relapse. The strategy for the present review of clinical trials was to ask 'What are the features of schizophrenia and the existing treatments of the illness that have implications for future clinical trials'? Six key facts were identified.First, schizophrenia is genetically 'complex'. Trials may benefit from designs including genetically related illnesses, by focussing on cross-cutting aspects of the phenotype such as psychosis or cognitive dysfunction, and by collecting information on possible moderators and mediators of treatment response.Second, schizophrenia affects multiple neurotransmitter systems. Multiple signalling pathways may need to be considered, with different time courses of response. Outcome measures from clinical trials could be collected at more frequent intervals, particularly in the early phase of response.Third, the clinical features used to define the illness are a mix of symptoms and social-occupational dysfunction, yet treatment response is often defined only by changes in symptoms. Multiple measures of functioning need to be collected at baseline and at the endpoint of trials. Consensus definitions for response, remission, relapse, recovery and recurrence need to be developed.Fourth, schizophrenia is often highly disabling. Linking treatment response in clinical trials to measures of quality-adjusted life-years will allow comparison with other medical illnesses using common metrics.Fifth, the general health and care of individuals with schizophrenia is often poor. 'Complex' interventions, which include, but are not limited to, antipsychotic medications, need to be designed and tested for the problems facing these patients.Finally, large gaps exist between clinical trials, practice guidelines and patterns of practice. Trials need to be designed to investigate widely used approaches such as antipsychotic polypharmacy, where actual practice diverges from evidence-based guidelines.

Clinical trials in children with Down syndrome: Issues from a cognitive research perspective

Clinical and translational research play a key role in the transition of basic research discoveries to effective therapies. In Down syndrome (DS), these research approaches are not well utilized or developed to test new therapies to improve cognitive and/or adaptive function in this population. This article reviews the history of clinical trial research in children with DS from a cognitive research perspective and discusses important issues relevant to the conduct of well designed clinical trials for this population. Specific issues addressed include: funding, study design, study medication, subject recruitment and retention, safety, and efficacy challenges. The Duke Down Syndrome Research Team's program of clinical research of cholinesterase inhibitors for individuals with DS serves as the model application for the identified research principles. It is hoped that this article will raise awareness of the unmet need for clinical research in the cognitive and adaptive function of individuals with DS, especially children with DS.