Ziprasidone versus olanzapine, risperidone or quetiapine in patients with chronic schizophrenia: a 12-week open-label, multicentre clinical trial

The effect of differences in trial design on estimates of efficacy of olanzapine in randomized studies

BACKGROUND

Differences in trial design may affect estimates of efficacy of psychotropic drugs. The purpose of this meta-analysis is to evaluate whether the use of Olanzapine (OLZ) as either investigational or control drug affects the observed efficacy of OLZ.

METHODS

We performed a search for Randomized-Controlled Trials (RCTs) in which the efficacy of OLZ is assessed in patients with schizophrenia or schizoaffective disorder. We assessed overall efficacy of OLZ and performed subgroup analyses of studies with OLZ as intervention or comparator. Mixed-effect meta-regression analyses were performed.

RESULTS

Of the 25 RCTs included, OLZ was considered as investigational drug or active control in 13 and 12 studies, respectively. The reduction of PANSS score was greater in trials in which OLZ was used as investigational drug. Multivariate meta-regression models showed that a higher PANSS score at baseline and trial duration were the main predictors of greater PANSS score reduction.

CONCLUSIONS

Trials with OLZ used as investigational drug differ from those of trials with OLZ as comparator for baseline PANSS scores and study duration; these differences may produce differences in estimates of efficacy. As a consequence, the severity of illness at enrollment and trial duration should be carefully considered to ensure the reliability of indirect comparisons among antipsychotics.

Systematic Literature Review of the Methods Used to Compare Newer Second-Generation Agents for the Management of Schizophrenia: A focus on Health Technology Assessment

BACKGROUND

The challenges of comparative effectiveness to support health technology assessment (HTA) agencies are important considerations in the choices of antipsychotic medications for the treatment of schizophrenia.

OBJECTIVES

Our aim was to assess the study methods used and outcomes reported in the published literature to address the question of comparative effectiveness of newer antipsychotic agents and the adequacy and availability of evidence to support HTA agencies.

DATA SOURCE

A systematic search of the PubMed database from 1 January 2009 to 30 September 2013 was conducted to identify studies evaluating new atypical antipsychotics reporting on comparative effectiveness.

STUDY SELECTION

The systematic review comprised of studies on schizophrenia patients where at least two drugs were being compared and at least one treatment group received one of the following second-generation antipsychotics: risperidone, olanzapine, aripiprazole, paliperidone, asenapine, iloperidone, lurasidone, and quetiapine. The included studies were also required to have an efficacy, safety or economic outcome, such as Positive and Negative Syndrome Scale (PANSS) score, weight gain, resource utilization, or costs.

STUDY APPRAISAL AND SYNTHESIS METHODS

Two reviewers (BW and GK) independently applied the inclusion criteria. Disagreements between reviewers were resolved by consensus, referring to the original sources. Information on the methodology and outcomes was collected for each included study. This included study description, head-to-head drug comparison, patient population, study methodology, statistical methods, reported outcomes, study support, and journal type.

RESULTS

A total of 198 studies were identified from electronic search methods. The largest category of studies was randomized controlled trials [RCTs] (N = 73; 36.9%), which were largely directed at the regulatory endpoint. Fewer studies were undertaken for HTA-purposes cohort studies (N = 53; 26.8%), meta-analyses (N = 32; 16.2%), economic studies (N = 14; 7.1%), and cross-sectional studies (N = 13; 6.6%). Direct head-to-head comparisons preferred by HTA were dominated by the comparison involving olanzapine and risperidone, representing 149 (75.3%) and 119 (60.1%) studies, respectively. RCTs, which are the primary study type for regulatory submissions, showed a lack of bias. Studies aimed at HTA were not as well performed. Cohort studies suffered from bias in the selection of comparison groups, lack of control for confounders, and differential dropout rates. As a group, cross-sectional studies scored poorly for bias, with a primary failure to identify a representative sample. Economic studies showed highly variable bias, with bias in the representation of effectiveness data, model assumptions without validation, and lack of sensitivity analyses.

LIMITATIONS

One limitation of this systematic review is that it only included studies from 2009 to 2013, potentially excluding some earlier comparator studies, particularly those involving first-generation antipsychotics.

CONCLUSIONS

This review of comparative effectiveness studies of second-generation antipsychotic agents for schizophrenic patients revealed a wide range of study types, study methodologies, and outcomes. For traditional efficacy outcomes and select safety outcomes, there is strong evidence from many well-conducted studies; however, there are fewer studies of types preferred by HTA with limited head-to-head comparisons and a higher risk of bias in the execution of these studies.

Evaluation of the pharmacokinetics, safety and clinical efficacy of ziprasidone for the treatment of schizophrenia and bipolar disorder

INTRODUCTION

Multiple strategies exist for the pharmacological treatment of schizophrenia and related disorders. In the last 20 years, several 'new' compounds have been introduced, called 'atypical antipsychotics', which have higher efficacy and better tolerability than first-generation neuroleptics. Among them, ziprasidone (ZPR) is currently finding widespread use, and it has also been shown to be active as an augmenter in bipolar disorder therapy.

AREAS COVERED

This review aims to provide the latest information on ZPR, an 'atypical' agent for the pharmacological therapy of schizophrenia and bipolar disorder. A literature search has been carried out with the keywords 'ziprasidone', 'schizophrenia', 'psychosis', 'bipolar', 'pharmacokinetics' and 'clinical trials'. In this process, particular attention has been paid to the drug pharmacokinetic characteristics and its safety in clinical use.

EXPERT OPINION

ZPR shares most advantages and disadvantages with other atypical antipsychotics. However, it can be useful for its low tendency to cause metabolic syndrome and hyperprolactinaemia, especially in patients suffering from excess weight, hyperlipidaemia, diabetes or who have suffered from hyperprolactinaemia when using other antipsychotics. However, there are serious doubts as to whether ZPR should be administered to patients suffering from arrhythmias or QTc prolongation, and even more for administration to bipolar patients undergoing polypharmacy with antidepressants.

The effectiveness of cross-tapering switching to ziprasidone in patients with schizophrenia or schizoaffective disorder

OBJECTIVE

Switching antipsychotics is one useful therapeutic option when the treatment of schizophrenia encounters suboptimal efficacy and intolerability issues. This study aimed to investigate the efficacy and tolerability of cross-tapering switching to ziprasidone from other antipsychotics.

METHODS

A total of 67 patients with schizophrenia or schizoaffective disorder were recruited in this 12-week, multicenter, non-comparative, open-label trial. Prior antipsychotics were allowed to be maintained for up to 4 weeks during the titration of ziprasidone. Efficacy was primarily measured using the 18-item Brief Psychotic Rating Scale (BPRS) at baseline, 4 weeks, 8 weeks, and 12 weeks. Efficacy was secondarily measured by the Clinical Global Impression-Severity (CGI-S) scale and the Global Assessment of Functioning (GAF) scale at each visit. Regarding the metabolic effects of switching to ziprasidone, weight, body mass index (BMI), waist-to-hip ratio (WHR), and lipid profile-including triglyceride (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), and total cholesterol levels-were measured at each follow-up visit.

RESULTS

The BPRS scores were significantly improved at 12 weeks after switching to ziprasidone (F=5.96, df=2.11, p=0.003), whereas the CGI-S and GAF scores were not significantly changed. BMIs, WHRs, and TG levels were significantly decreased, with no significant changes in other lipid profiles.

CONCLUSION

Cross-tapering switching to ziprasidone is effective for patients with schizophrenia spectrum disorders. Beyond the efficacy of the procedure, favorable metabolic profiles show that switching to ziprasidone may be helpful for maintenance therapy over an extended period.

Olanzapine in Chinese patients with schizophrenia or bipolar disorder: a systematic literature review

BACKGROUND

Despite the burden of schizophrenia and bipolar disorder in the Chinese population, country-specific data to guide practitioners regarding antipsychotic therapy are lacking. The primary aim of this systematic review was to examine evidence of the efficacy, effectiveness, and safety of olanzapine in Chinese populations.

METHODS

A systematic literature search was conducted using databases covering international and Chinese core journals using search terms related to schizophrenia and bipolar disorder, specified countries (People's Republic of China, Hong Kong, Taiwan), and olanzapine treatment. Following initial screening, inclusion and exclusion criteria were applied to the search results to identify relevant studies from which data were extracted.

RESULTS

A total of 489 publications were retrieved and 61 studies were identified for inclusion. Most studies were related to schizophrenia (n=54), with six studies related to bipolar disorder and one study related to both conditions. The quality of study methods and reporting in international journals was noticeably better than in Chinese language journals. Most studies included relatively small patient populations and were of short duration. The efficacy of olanzapine in Chinese populations was confirmed by multiple comparative and noncomparative studies that found statistically significant reductions in symptom measures in studies conducted for ≥6 weeks (schizophrenia) or ≥3 weeks (bipolar disorder). Findings related to effectiveness (treatment discontinuation, quality of life, and neurocognitive improvements) were generally consistent with those observed in non-Chinese populations. No new safety signals specific for Chinese populations were raised for olanzapine.

CONCLUSION

Chinese and non-Chinese populations with schizophrenia or bipolar disorder treated with olanzapine display broadly similar responses. Differences between these populations, especially in relation to the relative efficacy of olanzapine versus other antipsychotics, may warrant further investigation via studies incorporating both populations. Use of local data to provide evidence for practice guidelines should be encouraged, and may promote ongoing improvements in the quality of research and study reporting.

Switching to ziprasidone in the clinical practice setting: an open-label study

OBJECTIVE

This observational study evaluates the long-term outcome of switching to ziprasidone in patients with schizophrenia in the clinical practice setting.

METHODS

Patients (208) with schizophrenia who had been switched to ziprasidone monotherapy due to partial response or tolerability problems were followed for 1 year. Efficacy was assessed at baseline and months 1, 3, and 12 with Brief Psychiatric Rating Scale (BPRS), Clinical Global Impression-severity (CGI-S), and CGI-improvement. Quality of life, functionality, and safety measures, including metabolic parameters, were also assessed; 195 subjects comprised the per protocol analysis population.

RESULTS

A reduction > or = 30% in BPRS total score was observed in 42.5% of the subjects. Mean scores of the BPRS (global and positive and negative clusters), CGI-S and CGI-I significantly decreased at endpoint (p < 0.001). Ziprasidone treatment was also associated with statistically significant improvements in the GAF, WHO-DAS-II, and SF-12. After 1-year follow-up, a mean weight decrease of -1.6 kg (p < 0.05) was observed. Mean levels of LDL cholesterol and triglycerides also decreased (p < 0.01) while HDL cholesterol levels increased (p < 0.05) at endpoint. No significant changes in mean glucose levels at study end were detected.

CONCLUSION

These findings suggest that switching to ziprasidone is effective and well tolerated in patients with schizophrenia requiring a change in antipsychotic medication.

Medical needs in the treatment of psychotic disorders

Schizophrenia and psychotic disorders represent psychiatric disease patterns characterized by remarkable impairment arising from alterations in cognition, perception, and mood. Although these severe illnesses have been known for more than 100 years, psychopharmacological treatment of their characteristically broad spectrum of symptoms as well as patients' quality of life, compliance, and time to relapse still remain a challenge in everyday clinical practice. In the following, we will provide a brief synopsis of first-generation antipsychotics (FGAs) followed by a detailed description of current second-generation antipsychotics (SGAs) along with their effects and side effects to evaluate unmet needs in the treatment of schizophrenia and psychotic disorders.Overall, drug profiles differ concerning their efficacy, associated side effects, cost, and mechanism of action. Thus, a shared decision-making process taking all these factors into account is necessary to develop an effective treatment based on currently approved compounds. To date, however, the spectrum of options is limited and only serves a limited proportion of patients. In addition, certain symptoms do not respond well to currently available strategies or respond only at the price of considerable side effects leading to reduced compliance and adherence in a substantial number of cases.Unmet needs in the field of antipsychotic treatment are found in a wide range of areas starting from efficacy, safety and tolerability, compliance and adherence, and continuing to stage-dependent and more personalized approaches.

Comparison of metabolic effects of ziprasidone versus olanzapine treatment in patients with first-episode schizophrenia

OBJECTIVE

The objective of the study was to compare metabolic effects of ziprasidone versus olanzapine treatment in patients with first-episode schizophrenia.

METHODS

In this 6-week, multicenter, open-label trial, 260 patients were randomly assigned to receive ziprasidone or olanzapine treatment (130 per group). Primary metabolic measures were changes in weight and body mass index (BMI). Secondary metabolic measures were changes in glucose, insulin, lipids, and blood pressure. Efficacy and safety were also measured additionally.

RESULTS

A total number of 230 patients completed the study. The mean daily dosages were 138.2(28.6) mg for ziprasidone and 19.0(2.3) mg for olanzapine. After 6-week treatment, there were significant between-group differences in change scores on weight [4.22(3.49) kg versus -0.84(2.04) kg, p < 0.001] and BMI [1.59(1.37) versus -0.30(0.74), p < 0.001]. In addition, there were significant between-group differences in change scores on fasting plasma glucose, insulin, homeostasis model assessment 2-insulin resistance, low-density lipoprotein, total cholesterol, and triglycerides (p < 0.001); all the changes were clinically in favor of ziprasidone treatment. Both medications were effective in improving schizophrenia symptoms, but the decreases in Positive and Negative Syndrome Scale total scores of the olanzapine group were significantly greater than that of the ziprasidone group (p < 0.05). Compared with olanzapine, ziprasidone also induced more prolonging of corrected QT interval and extrapyramidal side effects (p < 0.05). Both medications were well tolerated, and no serious adverse events were observed in either group.

CONCLUSIONS

Compared with olanzapine, ziprasidone treatment was associated with less adverse effects on glucose and lipid metabolism in patients with first-episode schizophrenia.

Switching among antipsychotics in everyday clinical practice: focus on ziprasidone

OBJECTIVES

This article addresses points to consider when switching patients to the second-generation antipsychotic (SGA), ziprasidone, in everyday clinical practice: 1) the pharmacologic properties of the pre-switch antipsychotic and of ziprasidone; 2) switch and dosing strategies to ensure maintenance or attainment of efficacy; 3) recognition and management of possible rebound effects of the pre-switch medication discontinuation; 4) recognition and management of potential side effects of ziprasidone; and 5) education and support for patients/caregivers concerning correct ziprasidone administration.

METHODS

A Medline search (up to July 7, 2010) identified studies in which adult patients with schizophrenia were switched to ziprasidone from another antipsychotic. In addition, based on their extensive clinical experience, an expert faculty of European psychiatrists provided advice on identifying patients who may be appropriate candidates for switching to ziprasidone, and on establishing optimal strategies for switching to ziprasidone in everyday clinical practice.

RESULTS

Data from 10 studies, in which 1395 patients were switched to ziprasidone, showed that switching from first-generation antipsychotics (FGAs) or SGAs generally resulted in maintenance or improvement of efficacy across all studied symptom domains, improvements in tolerability, and acute and long-term benefits regarding cardiometabolic parameters, including body weight. Maintenance of efficacy is most likely to be achieved using a plateau cross-titration strategy, with a rapid uptitration of ziprasidone to a dose range of 60 to 80 mg administered twice daily with food. Temporary coadministration of benzodiazepines, anticholinergics, or beta-blockers should be considered for the management of potential rebound effects.

CONCLUSION

Optimal switching of patients with schizophrenia from FGAs or SGAs to ziprasidone requires careful attention to differences in the pharmacological profiles of the pre-switch medication and of ziprasidone, which may impact efficacy and tolerability. Good communication between the clinician and patient/caregiver about the goals of switching, the importance of adherence to the chosen switch strategy, and the correct administration of ziprasidone are essential.

Ziprasidone hydrocloride: what role in the management of schizophrenia?

Background

Since schizophrenia is considered one of the top ten causes of disease-related disability in the world, the development of second-generation (atypical) antipsychotics (SGAs) has increased the hopes of psychiatrists. SGAs, however, cannot be considered a unique pharmacological class since each SGA has many complex pharmacologic actions, only some of which are shared with other SGAs. Even though manyantipsychotics have similar efficacy on average, prescribers may be able to achieve better than average results by considering differences in selecting a specific drug for a specific patient. Clinicians know that each patient is unique. In order to achieve best outcomes for the individual patient, the better therapy is the therapy tailored for the single patient.

Objectives

With this article, we provide information on a relatively new antipsychotic ziprasidone released in 2001 by Pfizer for the treatment of schizophrenia. Compared with other first line atypical antipsychotics ziprasidone has a unique profile due to potent interaction with serotonergic receptors and lesser action upon α1 adrenergic, H1 and M1 antagonist activities. This paper describes the development of ziprasidone, its unique properties and its metabolically-friendly profile including its receptor binding affinities, pharmacokinetics, CNS activity results of clinical efficacy and relevant clinical trials. Safety, efficacy and patient preference are also examined. The available literature on ziprasidone of the last five years is reviewed.

Ziprasidone versus other atypical antipsychotics for schizophrenia

BACKGROUND

In many countries of the industrialised world second generation ('atypical') antipsychotics have become the first line drug treatment for people with schizophrenia. The question as to whether, and if so how much, the effects of the various new generation antipsychotics differ is a matter of debate. In this review we examined how the efficacy and tolerability of ziprasidone differs from that of other second generation antipsychotics.

OBJECTIVES

To evaluate the effects of ziprasidone compared with other atypical antipsychotics for people with schizophrenia and schizophrenia-like psychoses.

SEARCH STRATEGY

We searched the Cochrane Schizophrenia Group Specialised Register (April 2007) and references of all identified studies for further trial citations. We contacted pharmaceutical companies and authors of trials for additional information.

SELECTION CRITERIA

We included all randomised, at least single-blind, controlled trials comparing oral ziprasidone with oral forms of amisulpride, aripiprazole, clozapine, olanzapine, quetiapine, risperidone or zotepine in people with schizophrenia or schizophrenia-like psychoses.

DATA COLLECTION AND ANALYSIS

We extracted data independently. For continuous data, we calculated weighted mean differences (MD) for dichotomous data we calculated relative risks (RR) and their 95% confidence intervals (CI) on an intention-to-treat basis based on a random-effects model. We calculated numbers needed to treat/harm (NNT/NNH) where appropriate.

MAIN RESULTS

The review currently includes nine randomised controlled trials (RCTs) with 3361 participants. The overall rate of premature study discontinuation was very high (59.1%). Data for the comparisons of ziprasidone with amisulpride, clozapine, olanzapine, quetiapine and risperidone were available. Ziprasidone was a less acceptable treatment than olanzapine (leaving the studies early for any reason: 5 RCTs, n=1937, RR 1.26 CI 1.18 to 1.35, NNH 7 CI 5 to 10) and risperidone (3 RCTs, n=1029, RR 1.11 CI 1.02 to 1.20, NNH 14 CI 8 to 50), but not than the other second generation antipsychotic drugs. Ziprasidone was less efficacious than amisulpride (leaving the study early due to inefficacy: 1 RCT, n=123, RR 4.72 CI 1.06 to 20.98, NNH 8 CI 5 to 50) olanzapine (PANSS total score: 4 RCTs, n=1291, MD 8.32 CI 5.64 to 10.99) and risperidone (PANSS total score: 3 RCTs, n=1016, MD 3.91 CI 0.27 to 7.55). Based on limited data there were no significant differences in tolerability between ziprasidone and amisulpride or clozapine. Ziprasidone produced less weight gain than olanzapine (5 RCTs, n=1659, MD -3.82 CI -4.69 to -2.96), quetiapine (2 RCTs, n=754, RR 0.45 CI 0.28 to 0.74) or risperidone (3 RCTs, n=1063, RR 0.49 CI 0.33 to 0.74). It was associated with less cholesterol increase than olanzapine, quetiapine and risperidone. Conversely ziprasidone produced slightly more extrapyramidal side-effects than olanzapine (4 RCTs, n=1732, RR 1.43 CI 1.03 to 1.99, NNH not estimable) and more prolactin increase than quetiapine (2 RCTs, n=754, MD 4.77 CI 1.37 to 8.16), but less movement disorders (2 RCTs, n=822, RR 0.70 CI 0.51 to 0.97, NNT not estimable) and less prolactin increase (2 RCTs, n=767, MD -21.97 CI -27.34 to -16.60) than risperidone.

AUTHORS' CONCLUSIONS

Ziprasidone may be a slightly less efficacious antipsychotic drug than amisulpride, olanzapine and risperidone. Its main advantage is the low propensity to induce weight gain and associated adverse effects. However, the high overall rate of participants leaving the studies early limits the validity of any findings.