Skip to main content
Open access
REVIEWS AND OVERVIEWS
Published Online: 29 June 2020

Updating the Comparative Evidence on Second‐Generation Antipsychotic Use With Schizophrenia

Publication: Psychiatric Research and Clinical Practice

Abstract

Objective

The objective of this study was to conduct a systematic review of literature comparing second‐generation antipsychotics (SGAs) with each other and with first‐generation antipsychotics (FGAs) in treating schizophrenia.

Methods

MEDLINE, the Cochrane Library, and PsycINFO databases were searched through January 2020. Following standard methods, recent high‐quality systematic reviews of each drug comparison and subsequently published primary studies were included to update the meta‐analyses with any new data. Two reviewers independently conducted study selection, abstraction, and quality assessment.

Results

Two systematic reviews and 29 newer trials (total of 162 trials of SGAs, N=53,861; 116 trials of SGAs versus FGAs, N=119,558) were included. Most trials were of fair quality, industry‐funded, and included older SGAs and a few recently approved SGAs (asenapine, lurasidone, iloperidone, cariprazine, brexpiprazole and long‐acting injection [LAI] formulations of aripiprazole and paliperidone). Older SGAs had similar effects on function, quality of life, mortality, and adverse event incidence, although clozapine improved symptoms more than most other drugs and olanzapine and risperidone were superior to some other drugs. Olanzapine, risperidone, ziprasidone, and aripiprazole performed similarly on outcomes of benefit compared with haloperidol. Risperidone LAI and olanzapine resulted in fewer withdrawals due to adverse events, but risk of diabetes increased with olanzapine. Haloperidol had greater incidence of adverse events than did olanzapine and risperidone, but similar effects on other outcomes.

Conclusions

Most comparative evidence favored older SGAs, with clozapine, olanzapine, and risperidone superior on more outcomes than other SGAs. Older SGAs had similar benefits as haloperidol but with fewer adverse events.

HIGHLIGHTS

Use of the second‐generation antipsychotics olanzapine, aripiprazole, risperidone, quetiapine, and ziprasidone resulted in similar function, quality of life, mortality, and overall incidence of adverse events.
Core illness symptoms improved more with olanzapine and risperidone than asenapine, quetiapine, or ziprasidone, and more with paliperidone than lurasidone or iloperidone.
Haloperidol showed similar benefits but more adverse events than did olanzapine or risperidone.
Schizophrenia is a chronic mental health condition that most often manifests in early adulthood and can lead to episodic and varying levels of disability. The most recent version of the DSM‐5 (1) reflects the DSM‐III and DSM‐IV diagnostic criteria for schizophrenia, simplified and clarified, with no change in the defined patient population among the editions (2). DSM‐5 criteria define schizophrenia as the presence of two or more of five core symptoms (delusions, hallucinations, disorganized speech, grossly disorganized or catatonic behavior, and negative symptoms). At least one of the symptoms must be delusions, hallucinations, or disorganized speech, and symptoms must be present for at least 6 months. Lifetime prevalence is reported to be 0.3% to 0.7%, with onset most commonly occurring in late adolescence through the third decade (3). Differential diagnosis is broad and includes delineation from mood disorders (bipolar disorder or major depressive disorder) with psychotic features and substance and/or medication‐induced psychotic disorders. The course of schizophrenia varies; approximately 20% of patients may experience significant improvement, including, in some cases, full recovery (4). However, most patients experience some degree of social and occupational difficulty as well as need for support in daily living. Recent research and practice have focused on early intervention with first‐episode psychosis, which has demonstrated promise toward improving outcomes, reducing longer‐term disability, and improving the likelihood of full recovery (5).
A mainstay of early intervention is pharmacologic therapy (6). Antipsychotic medications act primarily via dopaminergic antagonism and can result in meaningful improvements in symptoms. Ideally, improvements in symptoms translate to long‐term, clinically relevant changes in other outcome areas, with limited, manageable adverse effects. Although efficacy trials of antipsychotics conducted for regulatory approval are limited to measurement of changes in symptoms, measurement of recovery‐oriented outcomes (e.g., remission) reflecting improvement in social and occupational functioning, and ultimately quality of life, are necessary. Historically, there has been uncertainty regarding the impact of antipsychotic drugs on long‐term patient‐centered outcomes, such as consistent employment, successful interpersonal relationships, maintenance of independent living, and the absolute and relative risk of serious long‐term adverse effects (e.g., tardive dyskinesia and diabetes). Many patients discontinue their prescribed antipsychotic medication, and discontinuation rates and time to discontinuation vary by treatment and patient characteristics. Older, first‐generation antipsychotics (FGAs), such as haloperidol, have proven efficacy in reducing symptoms, but adverse effects, such as extrapyramidal symptoms and sometimes tardive dyskinesia, often limit long‐term use. Second‐generation antipsychotics (SGAs) were introduced as having efficacy equal to or better than that of FGAs, particularly for negative symptoms, and possibly lower risk for the adverse events that limited use of FGAs (7, 8, 9). SGAs, however, also have potentially serious long‐term adverse effects (e.g., cardiovascular and endocrinological effects) that make their overall risk‐benefit profile less clear‐cut. Additionally, the specific mechanisms of action (e.g., interaction with dopamine receptors) and adverse effect profiles vary across the SGAs. Twelve SGAs (with 22 formulations) are currently marketed in the United States, along with several FGAs. Given the availability of newer drugs and formulations, and the need to select specific treatments for individual patients with schizophrenia, updated evaluation of the comparative evidence for a range of outcomes, including symptoms, function, and quality of life, associated with these drugs is important.
In this review, we aim to update and summarize the key findings of a systematic review on the comparative effectiveness of SGAs versus each other and versus FGAs as treatments for patients with schizophrenia. These findings are part of a broader report funded and published by the Agency for Healthcare, Research and Quality (AHRQ) (10). The review topic was nominated by the American Psychiatric Association (APA) to provide evidence in support of updating guidelines on treatments for schizophrenia. The full report includes evidence on psychosocial treatments and is much more detailed in both methods and results reporting but is less accessible for most readers.

METHODS

We adhered to AHRQ guidance for methodology in comparative effectiveness reviews (11, 12). The scope of this review was based on consultation with an APA guideline development group and was refined through consultation with experts. The Oregon Health and Science University Institutional Review Board determined that systematic reviews conducted by the Evidence‐Based Practice Center are not human subjects research. The protocol has been published on the AHRQ Effective Health Care website. The work was conducted between January 2016 and March 2017, with updating in January 2020. The draft of that report was revised based on comments from invited reviewers and comments received through public posting prior to finalization. In this review, we have updated the findings with new evidence published since the AHRQ report.

Literature Search and Study Selection

A research librarian searched MEDLINE, the Cochrane Central Register of Controlled Trials, the Cochrane Database of Systematic Reviews, PsycINFO, and web pages of organizations that fund systematic reviews through February 2017 for the AHRQ report, and conducted updated searches in MEDLINE through January 2020 for this manuscript. In accordance with AHRQ guidance to improve efficiency (13), we first searched for recent, high‐quality systematic reviews that had a similar scope to our AHRQ review; that is, reviews of randomized controlled trials (RCTs) of at least 12 weeks duration that directly compared SGAs with each other or an FGA for patients with schizophrenia. We included one review for any given drug comparison‐outcome pair, so that data from any given study were included only once. We then searched for and included RCTs that were published after we had searched for the included systematic reviews. We requested information from pharmaceutical manufacturers and searched reference lists of the included studies. Key outcomes were clinical and patient centered (i.e., focused on health outcomes) and were selected based on input from an expert panel. These outcomes were functional quality of life improvements, reductions in self‐harm, treatment discontinuation, symptom‐related outcomes, withdrawals due to adverse events, and significant adverse events (including deaths). Search results were independently screened for eligibility by two reviewers, with disagreements resolved by achieving consensus. Complete search strategies and lists of included studies and studies excluded after full‐text review can be found in the appendices of the full report (10).

Study Quality and Evidence Synthesis

By using predefined criteria (10), we assessed the quality of RCTs and systematic reviews. We evaluated the RCTs using methods developed by the Drug Effectiveness Review Project (14). We assessed systematic reviews by using A Measurement Tool to Assess Systematic Reviews (AMSTAR), a quality‐rating instrument (15). We rated studies as good, fair, or poor. Studies deemed poor quality, with multiple flaws, were considered less reliable and were not synthesized with higher‐quality studies. Study quality was independently assessed by two reviewers, with disagreements resolved by achieving consensus.
Meta‐analyses were considered, depending on the data available and the similarity among studies in design, patient populations, interventions, and outcomes. Meta‐analyses including systematic reviews were updated with data from newer trials where possible, and if no new data were available, the results of the meta‐analyses in the included reviews were reported. We used the DerSimonian and Laird random‐effects model for pairwise meta‐analyses. We updated the pair‐wise meta‐analyses by using StatsDirect, version 3.0 (Camcode). Statistical heterogeneity was assessed using the I2 statistic (16). We updated network meta‐analyses of symptom response, overall discontinuation of drug, and withdrawal due to adverse events that were initially conducted in the included systematic review of SGAs (17) by using Stata/SE, version 14.1 (StataCorp), and the Bayesian model was performed with OpenBUGS, version 3.2.3 (18, 19). We controlled the analysis for variation in study duration, mean daily dose levels (low, medium, and high), and whether studies enrolled patients with a first episode of schizophrenia or whose symptoms were resistant to prior treatment. We defined response as 20% improvement on the Positive and Negative Syndrome Scale (PANSS) or by using other scales, such as the Clinical Global Impression‐Improvement scale (CGI‐I) and combinations of these scales). Where results were not combinable in a meta‐analysis because of heterogeneous populations, interventions, comparators, or outcome measures, or where an important outcome was reported for a given comparison in only a single trial, we report individual trial results. There were not enough new data to update meta‐analyses of SGAs versus FGAs.
Strength of the body of evidence for each key outcome was assessed by using the approach outlined for AHRQ evidence‐based practice centers by evaluating the following domains: study limitations (i.e., cumulative study quality), consistency, directness of evidence, and precision of estimates (12, 20). We assigned overall grades of high, moderate, low, or insufficient based on the domain evaluations: high strength of the body of evidence indicated confidence in the estimate of effect, whereas moderate and low reflected lower levels of confidence such that future evidence could alter the results. A rating of insufficient indicated that no or very limited evidence was available or the body of evidence had unacceptable deficiencies, precluding reaching a conclusion.

RESULTS

We included a total of 278 RCTs (see flow diagram in the online supplement); one systematic review of 138 trials (N=47,189) (17) and 24 additional trials (N=6,672) (21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44) for SGAs versus other SGAs, and one systematic review of 111 trials (N=118,503) (45, 46) and five additional trials (N=1,055) (35, 47, 48, 49, 50) for FGAs versus SGAs. The two systematic reviews also included 33 cohort studies (N =652,505) (17, 45, 46). Table 1 provides an overview of characteristics of the included RCTs. Although most RCTs were 8 to 12 weeks in duration, some studies were longer (3 to 4 years). The typical patient was age 37 (younger in first‐episode studies) and male. Slightly less than 50% (N=137) of the studies were conducted solely in the United States, and close to 70% (N=193) were funded by the pharmaceutical industry. A majority of studies were judged to be of fair quality; key limitations of RCTs were unclear randomization procedures, unclear or lack of blinding of outcome assessors, and incomplete reporting. Older SGAs (clozapine, risperidone, olanzapine, quetiapine, ziprasidone, and aripiprazole) were most frequently studied, with little comparative evidence for the newest drugs (asenapine, brexpiprazole, cariprazine, iloperidone, lurasidone, paliperidone, and long‐acting injection [LAI] formulations of aripiprazole and pal‐iperidone). Detailed descriptions of studies and systematic reviews can be found in the full report 10). Among the included trials was the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) schizophrenia study (51, 52, 53, 54, 55), a large, good‐quality, federally funded effectiveness trial with three phases, examining four SGAs (clozapine, risperidone, olanza‐pine, and ziprasidone) and one FGA (perphenazine), with all‐cause treatment discontinuation as the primary outcome.
TABLE 1. Characteristics of RCTs (N=278) included in a review of second‐generation antipsychotics (SGAs) for patients with schizophrenia
MedicationSpecific comparisonsN of RCTsN of patientsMedian duration (range) % female participants 
Mean ageStudy quality
SGA vs. SGAMost were older SGAs (clozapine, risperidone, olanzapine, quetiapine, ziprasidone, and aripiprazole); few were newest drugs (long‐acting injectables, cariprazine, brexpiprazole)162a53,86112 weeks (6 weeks–3 years)37 years (26 years for first‐episode studies)22–77Good, 9%; fair, 73%; poor: 18%
FGAb vs. SGAMost comparisons involved haloperidol vs. olanzapine and/or risperidone.116c69,6008 weeks (1 day–4 years)37 years25–42Good, 0%; fair, 63%; poor, 37%
a
138 randomized controlled trials (RCTs) were included in a good‐quality systematic review, and 24 additional RCTs were identified.
b
FGA, first‐generation antipsychotic.
c
111 RCTs were included in a good‐quality systematic review, and five additional RCTs were identified.
Table 2 presents a summary of key findings and the strength of evidence according to drug comparison and outcome. Some harms outcomes (diabetes, weight gain, tardive dyskinesia, extrapyramidal symptoms, and changes in sexual function) were not addressed in the review of FGAs versus SGAs. No body of evidence in these areas met criteria for high‐strength evidence, primarily because of limitations of the individual studies, lack of precise estimates, and inconsistencies across studies (see online supplement). Detailed tables of individual study characteristics, results and quality assessments, and domain‐based ratings of the strength of the bodies of evidence are available in the full report (10). Estimates of comparative risk are reported below only when they are statistically significant.
TABLE 2. Summary of key findings and strength of evidence in a review of second‐generation antipsychotics (SGAs), by outcomea
OutcomeModerate strength of evidenceLow strength of evidence
Improved social function Risperidone LAI significantly better than quetiapine in social function over 24 months. No difference between paliperidone palmitate LAI (monthly) and risperidone LAI (every 2 weeks).
Improved occupational function No significant differences between risperidone, olanzapine, quetiapine, or ziprasidone at 18 months (CATIE).
Improved global functioning Global functioning did not differ between olanzapine and either risperidone or quetiapine.
Improved quality of lifeOlanzapine did not significantly differ from risperidone, ziprasidone, haloperidol, or perphenazine. Perphenazine did not significantly differ from quetiapine, risperidone, or ziprasidone.Olanzapine and risperidone did not significantly differ from quetiapine. Risperidone LAI did not significantly differ from quetiapine. Oral aripiprazole did not significantly differ from aripiprazole monthly LAI.
ResponseRisperidone did not significantly differ from haloperidolResponse was significantly more likely with olanzapine and risperidone than quetiapine and with olanzapine than with haloperidol. Haloperidol did not significantly differ from aripiprazole, quetiapine, or ziprasidone.
Mortality No difference between asenapine and olanzapine, quetiapine and risperidone, paliperidone palmitate LAI (monthly) and risperidone, LAI risperidone and olanzapine or quetiapine, or olanzapine and quetiapine (including cardiovascular mortality).
Self‐harmClozapine was superior to olanzapine in preventing significant suicide attempts or hospitalization to prevent suicide in high‐risk patientsClozapine was associated with lower risk of suicide or suicide attempts than were olanzapine, quetiapine, or ziprasidone.
Improved total scale scoresOlanzapine and risperidone improved symptoms more than haloperidolClozapine improved symptoms more than the other SGAs, except for olanzapine. Olanzapine and risperidone improved symptoms more than most other SGAs (except for each other and for paliperidone). Paliperidone improved symptoms more than lurasidone and iloperidone did. In patients with treatment‐resistant disorders, olanzapine improved symptoms more than quetiapine.
Overall adverse eventsOverall incidence of adverse events did not differ between olanzapine and asenapine. Haloperidol had greater risk of any adverse event than did aripiprazole, risperidone, and ziprasidone.No significant differences were found between Quetiapine ER vs. quetiapine and risperidone; risperidone vs. clozapine and aripiprazole; olanzapine vs. paliperidone; risperidone LAI vs. paliperidone and paliperidone palmitate monthly LAI; and aripiprazole vs. aripiprazole monthly LAI.
Withdrawal due to adverse eventsHaloperidol had greater risk of withdrawals due to adverse event than aripiprazole, olanzapine, risperidone, or ziprasidone.Based on a network meta‐analysis of 90 trials, risperidone LAI had significantly lower risk than clozapine, lurasidone, quetiapine ER, risperidone, and ziprasidone. Olanzapine had lower risk than clozapine, lurasidone, quetiapine, risperidone, and ziprasidone. Aripiprazole had lower risk than clozapine and ziprasidone. Cariprazine and iloperidone had lower risk than clozapine.
a
No interventions met high strength of evidence criteria for any outcome (see online supplement for details of strength of evidence ratings and effect sizes). CATIE, Clinical Antipsychotic Trials of Intervention Effectiveness; ER, extended release; IR, immediate release; LAI, long‐acting injectable.

Function

SGA versus SGA

No significant differences in social junction outcomes, as assessed by a variety of measures, were found between the older oral SGAs, between paliperidone palmitate monthly LAI and risperidone biweekly LAI, or between risperidone and cariprazine (17, 28). Social functioning was better with risperidone LAI than with quetiapine, as measured by the Social and Occupational Functioning Assessment Scale at 6 to 18 months (one RCT, between‐group differences 3.4 to 5.5 on a 100‐point scale) (56). CATIE phase 1 found no significant differences in rates of employment among patients taking risperidone, olanzapine, quetiapine, perphenazine, and zipra‐sidone at 18 months. Global functioning did not differ (as measured by the Global Assessment of Functioning [GAF] scale) among patients taking olanzapine and risperidone (four cohort studies) or quetiapine (two RCTs) (17).

FGA versus SGA

In studies comparing FGAs and SGAs, outcomes related to function were rarely reported, with no significant differences reported for any measure of function (45). This evidence included single studies comparing the effects of haloperidol with olanzapine, quetiapine, or ziprasidone on patients' GAF scores, single studies comparing the use of perphenazine with olanzapine, quetiapine, risperidone, or ziprasidone on the proportion of patients with paid employment, and a trial of the effects of haloperidol versus risperidone on patients' economic independence.

Quality of Life

SGA versus SGA

Although there were small improvements from baseline, quality of life did not differ among patients taking older SGAs (clozapine, risperidone oral and LAI, olanzapine, quetiapine, and ziprasidone). Olanzapine did not significantly differ from risperidone (two RCTs), ziprasidone (two RCTs), or quetiapine (one RCT), and risperidone did not differ from quetiapine or ziprasidone (one RCT each) at 12 months, as assessed by patient results on the HeinrichCarpenter Quality of Life Scale. Risperidone LAI did not differ from quetiapine on patient results on the Short Form Health Survey or the Schizophrenia Quality of Life Scale–Revision 4 at 24 months (one RCT) (17).

FGA versus SGA

The evidence comparing FGAs and SGAs did not support a differential effect in quality of life, as determined by various measures. Two trials reported inconsistent findings between haloperidol and ziprasidone; five RCTs reported no differences between haloperidol and olanzapine; and one RCT each found no differences between perphenazine and olanzapine, quetiapine, risperidone, or ziprasidone (45).

Response, Improvement in Symptoms, and Relapse

SGA versus SGA

Response to treatment was significantly more likely with olanzapine (five RCTs, odds ratio [OR]=1.71, 95% confidence interval [CI]=1.11 to 2.68) and risperidone (nine RCTs, OR=1.41, 95% CI=1.01 to 2.00) than with quetiapine, according to a network meta‐analysis of head‐to‐head RCTs (N=12,536) (see online supplement) (17). Response ranged from 20% to 80% in individual study arms. A metaregression examining study duration, dose level, treatment resistance, or first‐episode status, and response definition did not identify any predictors of response.
Clozapine was found to improve symptoms (as assessed by scores on the PANSS or Brief Psychiatric Rating Scale) significantly more than the other SGAs (standardized mean differences [SMDs]=−0.32 to −0.55) (57). Olanzapine and risperidone were similar to each other, but demonstrated greater improvements than the other SGAs, except for paliperidone (SMDs=−0.13 to −0.26) (57). Paliperidone was found to improve symptoms more than lurasidone and iloperidone (both SMDs=−0.17).
The evidence on relapse suffers from lack of blinding, high attrition, and lack of a consistent definition of relapse (17). Evidence on the comparison of olanzapine with risperidone and quetiapine was inconsistent, and conclusions could not be drawn. Risperidone LAI resulted in lower relapse rates than oral risperidone (5% to 18% versus 33% to 50%; p<0.010) or quetiapine (16.5% versus 31.3%; p<0.001) at 1 year (one RCT each). In the few studies available, no differences were found in comparisons of risperidone and quetiapine to each other or to clozapine and lurasidone. No differences in relapse rates were found for comparisons of lurasidone and quetiapine extended release (ER) or risperidone, risperidone and quetiapine ER, olanzapine and aripiprazole, or aripi‐prazole LAI or risperidone LAI.
For patients with first‐episode psychosis, no significant differences were found between oral olanzapine, quetiapine, risperidone, ziprasidone, aripiprazole, or paliperidone (17 RCTs) in response, remission, or symptom improvement, regardless of study duration, specific drugs, age or gender, history of cannabis use disorder, or treatment blinding, but aripiprazole resulted in more weight gain than ziprasi‐done (17).

FGA versus SGA

Compared with haloperidol, olanzapine use was associated with greater response (14 RCTs, relative risk [RR]=0.86, 95% CI=0.78 to 0.96) and remission (three RCTs; RR=0.64, 95% CI=0.45 to 0.94) (45). There was no difference in response between haloperidol and aripiprazole, quetia‐pine, risperidone, and ziprasidone and no difference in remission versus ziprasidone (45).
Reductions in symptoms were greater with older SGAs than with haloperidol. Compared with haloperidol, total PANSS scores were better with olanzapine (15 RCTs, mean difference [MD]=2.31, 95% CI=0.44 to 4.18) and risperidone (21 RCTs, MD=3.24, 95% CI=1.62 to 4.86).
For patients with a first episode of schizophrenia and/or psychosis, the evidence showed no significant differences between FGAs and SGAs. Among patients with treatment‐resistant disorders, response was significantly better with ziprasidone (one RCT, RR=1.54, 95% CI=1.19 to 2.00) than with FGAs.

Discontinuation of Treatment

SGA versus SGA

Results of a network analysis (111 studies, N=32,096) found that olanzapine and clozapine had significantly lower treatment discontinuation rates than asenapine, cariprazine, iloperidone, lurasidone, olanzapine LAI, que‐tiapine, risperidone, and ziprasidone (odds ratios [ORs] ranged from 0.42 for clozapine versus iloperidone to 0.69 for clozapine versus risperidone) (17). Clozapine also resulted in lower risk of treatment discontinuation than paliperidone palmitate monthly LAI (OR=0.56, 95% CI=0.33 to 0.92), and olanzapine resulted in lower risk than paliperidone (OR=0.67, 95% CI=0.50 to 0.89). Quetiapine ER resulted in lower risk of treatment discontinuation than iloperidone (OR=0.28, 95% CI=0.09 to 0.84), olanzapine LAI (OR=0.31, 95% CI=0.09 to 0.99), or quetiapine (OR=0.35, 95% CI=0.12 to 0.88), and both risperidone and aripiprazole had lower risk than iloperidone (OR=0.62, 95% CI=0.43 to 0.90; OR=0.61, 95% CI=0.40 to 0.94, respectively) or quetiapine (OR=0.77, 95% CI=0.66 to 0.91; OR=0.76, 95% CI=0.61 to 0.95, respectively). Both risperidone (OR=0.62, 95% CI=0.43 to 0.90) and aripiprazole monthly LAI (OR=0.52, 95% CI=0.28 to 0.98) had lower risk of treatment discontinuation than iloperidone. A meta‐regression analysis examining study duration, dose level, and either treatment‐resistant or first‐episode status resulted in no significant findings.
Time to discontinuation was 2 to 4 months longer with olanzapine compared with quetiapine (17 studies), risperidone (31 studies), and ziprasidone (10 studies), on the basis of trial and observational evidence. Time to discontinuation may be longer with clozapine (7.2 to 7.8 months longer) than with olanzapine, risperidone, or quetiapine, as assessed by phase 2E of the CATIE trial (51).
Results of a network meta‐analysis (90 RCTs, N=29,678) revealed significantly lower withdrawals because of adverse events with risperidone LAI than with clozapine (OR=0.27, 95% CI=0.10 to 0.71), lurasidone (OR=0.39, 95% CI=0.18 to 0.84), quetiapine (OR=0.43, 95% CI=0.22 to 0.81), risperidone (OR=0.50, 95% CI=0.25 to 0.99), and ziprasidone (OR=0.40, 0.20 to 0.82). Olanzapine had lower risk than clozapine (OR=0.39, 95% CI=0.19 to 0.79), lurasidone (OR=0.57, 95% CI=0.34 to 0.94), quetiapine (OR=0.62, 95% CI=0.44 to 0.87), risperidone (OR=0.72, 95% CI=0.55 to 0.96), and ziprasidone (OR=0.58, 95% CI=0.41 to 0.82). Aripiprazole had lower incidence of withdrawals than ziprasidone (OR=0.64, 95% CI=0.44 to 0.94) and clozapine (OR=0.43, 0.21 to 0.88). Cariprazine (OR=0.40, 95% CI=0.17 to 0.95) and iloperidone (OR=0.34, 95% CI=0.13 to 0.91) had lower risk of withdrawal than clozapine. Our meta‐regression analysis resulted in no significant findings.

FGA versus SGA

All‐cause discontinuation of treatment was not reported in the systematic review of FGAs versus SGAs (45). However, withdrawals due to adverse events were significantly higher with haloperidol use compared with aripi‐prazole (eight RCTs, RR=1.25), olanzapine (24 RCTs, RR=1.89), risperidone (25 RCTs, RR=1.32), and ziprasidone (27 RCTs, RR=1.68) (35, 45, 47, 48, 49). There were no differences in withdrawal due to adverse events in comparisons of haloperidol and clozapine (five RCTs) or quetiapine (10 RCTs). On the basis of single studies for each comparison, no significant differences were found in comparisons of haloperidol to asenapine; fluphenazine to olanzapine or quetiapine; and perphenazine to aripiprazole, olanzapine, quetiapine, risper‐idone, or ziprasidone.

Mortality and Self‐Harm

SGA versus SGA

In 10 RCTs, incidence of all‐cause mortality was low, and did not differ between the SGAs over 4 to 24 months; evidence was not available for the newest SGAs (10, 21, 33, 58, 59, 60, 61, 62, 63, 64, 65). In a good quality RCT, among patients at high risk for suicide, clozapine was found to be superior to olanzapine in preventing substantial suicide attempts or hospitalization to prevent suicide (hazard ratio [HR]=0.76, 95% CI=0.58 to 0.97) and in CGI‐Severity‐Suicidality Scale ratings (HR=0.78, 95% CI=0.61 to 0.99) (66). Two observational studies confirmed these findings in broader populations (67, 68).

FGA versus SGA

Mortality was not reported in the trials included in the systematic review comparing FGAs and SGAs, and the majority of trials excluded people at risk of suicide (45). No differences were found in risk of suicide outcomes between perphenazine or haloperidol and olanzapine (45) or between LAI haloperidol and LAI paliperidone, as evidenced by a single trial per comparison (50).

Diabetes Mellitus and Weight Gain

The evidence directly comparing SGAs on incidence of diabetes mellitus, ketoacidosis, and weight gain was limited and did not adequately control for confounding factors (17). Olanzapine was associated with increased risk of new‐onset diabetes compared with risperidone (six cohort studies, OR=1.16, 95% CI=1.03 to 1.31), but differences were not consistently found among other older SGAs (17). Evidence on the incidence diabetic ketoacidosis with olan‐zapine, risperidone, and quetiapine was inconsistent (two studies).
The risk of clinically important weight gain (≥7% increase) was greater with olanzapine than with aripiprazole, asenapine, clozapine, quetiapine, risperidone, or ziprasidone, with relative risks from 1.81 with risperidone to 5.76 with ziprasidone (55 RCTs) (17). Single studies found greater risk of weight gain with risperidone compared with aripiprazole (OR=4.74,95% CI=1.55 to 14.47) or cariprazine (RR=1.98,95% CI=1.03 to 3.80) and with aripiprazole compared with ziprasidone (OR=2.72, 95% CI=1.22 to 6.08) (10, 69). Single studies found no differences in weight change between olanzapine and olanzapine ER, olanzapine oral dissolving tablet, and paliperidone palmitate injection, or between aripiprazole and paliperidone or quetiapine.

Overall Adverse Event Incidence, Tardive Dyskinesia, Extrapyramidal Symptoms, and Sexual Function

There were no significant differences between the SGAs in the proportions of patients reporting any adverse event, as assessed by 72 RCTs and 31 drug comparisons (17). Observational evidence suggested that compared with olan‐zapine, risperidone significantly increased the risk of new‐onset tardive dyskinesia (OR=1.70, 95% CI=1.35 to 2.14), but not compared with clozapine or quetiapine (17). Rates of new‐onset tardive dyskinesia were 3% with risperidone and 1%‐2% for the other medications. The rates of patients experiencing extrapyramidal side effects (prevalent or incident) and severe symptoms mostly did not differ among the drugs, although use of anticholinergic medications was lower with quetiapine than with olanzapine, risperidone, or ziprasidone.
Evidence on sexual function revealed inconsistent findings; studies had small samples sizes and often lacked explicit methodology to measure symptoms (17). A study comparing risperidone and quetiapine ER (N=798) found that significantly more men reported adverse sexual effects with ris‐peridone at 6 months (13% versus 6%; p<0.050), but the difference was not significant at 12 months. Four very small trials of risperidone compared with quetiapine were inconclusive, and individual trials found no significant differences in results between olanzapine and paliperidone, risperidone, or ziprasidone or between risperidone and paliperidone or aripiprazole.
Overall adverse event rates (incidence of any adverse event) were greater with haloperidol than with aripiprazole (three RCTs, RR=1.11; 95% CI=1.06 to 1.17), risperidone (eight RCTs, RR=1.20, 95% CI=1.01 to 1.42), and ziprasidone (six RCTs, RR=1.13, 95% CI=1.03 to 1.23). Withdrawals due to adverse events were significantly higher with haloperidol than with SGAs: compared with aripiprazole (eight RCTs, RR=1.25, 95% CI=1.07 to 1.47), olanzapine (24 RCTs, RR=1.89; 95% CI=1.57 to 2.27), risperidone (25 RCTs, RR=1.32; 95% CI=1.09 to 1.60), and ziprasidone (seven RCTs, RR=1.68, 95% CI=1.26 to 2.23).

New Evidence

Since the finalization of the AHRQ report, we identified two new, small RCTs that focused on long‐acting injectable formulations: a 12‐month study conducted in Italy of patients with co‐occurring substance use disorder (aripiprazole LAI versus paliperidone LAI) and a 13‐week study conducted in China of patients with first‐episode schizophrenia (paliperidone LAI versus oral olanzapine) (70, 71). These studies showed no differences in symptom‐based outcomes or in weight gain for the 13‐week study of first‐episode patients (71). Results of the study of patients experiencing comorbid substance use disorder and psychosis (89% with schizophrenia, 11% with bipolar disorder) (70) revealed better improvement on cravings and some quality of life measures with aripiprazole; however, baseline differences between the groups suggest that caution must be used in interpreting these findings.

DISCUSSION

We evaluated the evidence on antipsychotic medications for schizophrenia, comparing drugs with each other, from 278 RCTs among 173,419 patients. Trials were mostly of fair quality (i.e., moderate risk of bias), and bodies of evidence for specific outcomes and intervention pairs were primarily of low and moderate strength, meaning we had low‐to‐moderate confidence that the findings were stable (i.e., are unlikely to change significantly with additional evidence). The majority of evidence from head‐to‐head drug trials was about older SGAs, with sparse data on SGAs approved in the past 10 years (asenapine, lurasidone, iloperidone, cariprazine, brexpipra‐zole) and recent long‐acting injection formulations of aripi‐prazole and paliperidone. Older SGAs were similar in measures of function, quality of life, mortality, and overall and/or any adverse events, except that patients taking risperidone LAI demonstrated better social function than patients taking que‐tiapine. Symptoms improved more with olanzapine and ris‐peridone than with asenapine, quetiapine, and ziprasidone and more with paliperidone than lurasidone and iloperidone; all were superior to placebo. Risperidone LAI and olanzapine resulted in less withdrawal due to adverse events. Compared with olanzapine and risperidone, haloperidol, the most studied FGA, resulted in similar improvement in symptoms, symptom response, and remission but greater incidence of adverse event outcomes, such as tardive dyskinesia.
These findings are consistent with findings of prior systematic reviews that have made comparisons among the SGAs and between SGAs and FGAs, although our findings differed to some extent from previous reviews because we considered outcomes prioritized with input from technical experts, incorporated newer evidence and the most recently approved drugs, and included three updated network metaanalyses (57, 72, 73, 74, 75, 76). For example, in comparing SGAs, our network meta‐analyses of patient response, withdrawal due to adverse events, and all‐cause treatment discontinuation incorporated evidence on brexpiprazole and cariprazine, the two most recently approved oral drugs, and all of the long‐acting injection SGAs, whereas previously published network meta‐analyses were limited to older oral drugs, did not control for important potential effect modifiers, and included drugs not approved in the United States (57, 72, 74, 76, 77, 78, 79). Our review is consistent with other reviews of the older SGAs in that clozapine, risperidone, and olanzapine showed the most consistent evidence of superiority for specific outcomes (e.g., symptom improvement, response, self‐harm, all‐cause treatment discontinuations, and time to discontinuation) or populations (those with a first episode or treatment‐resistant disorders) (75, 78, 80, 81, 82). Some of our other findings are new, such as the finding that risperidone LAI and olan‐zapine resulted in significantly fewer withdrawals caused by adverse events than most other SGAs. Our findings on FGAs versus SGAs are mainly consistent with those of a prior review (45), which concluded that there were few clinically important differences in effectiveness outcomes and that the evidence on "patient‐important" outcomes and adverse events was not well studied. New findings include moderate‐strength evidence of specific SGAs resulting in better symptom improvement (olanzapine and risperidone) and lower rates of overall adverse events (aripiprazole) and withdrawal due to adverse events (aripiprazole, olanzapine, risperidone, and ziprasidone) than haloperidol.
Potential limitations of our review included decisions that were made regarding eligibility criteria for the AHRQ report. Because the scope of the overall report was broad, incorporating both drug and psychosocial interventions, with a strict budget and time line, some decisions were made to improve efficiency. These constraints included focusing on longer‐term outcomes, limiting studies to those of 12 weeks or longer, including only studies that directly compared the drugs, and incorporating preexisting systematic reviews. These decisions were made after consultation with an expert panel, AHRQ, and representatives of the APA guideline group, and the protocol was posted publicly. The duration threshold reflected the clinical consideration that treatments are typically given for extended periods and that results found in short‐term trials are not always sustained. Limiting the review to head‐to‐head trials also reflected our experience that the findings of indirect comparisons using placebo‐controlled trials can be misleading (83, 84). This finding may be due to the narrower inclusion criteria used by most trials designed for drug approval, and, importantly with antipsychotics, some drugs had doses way above those used clinically today. There may be concern that our use of two preexisting systematic reviews may have resulted in double‐counting data from some studies. Each of the reviews focused on disparate comparisons, such that data for comparisons were not included twice. For example, if an RCT had three arms, two with SGAs and one with an FGA, data for the SGA comparison were included in one of the reviews, whereas data from the FGA versus SGA comparison were included only in the other review.
The findings of this review are applicable to adults (mean age 25 to 50) with mainly moderate and moderate‐to‐severe disease. There was fairly robust evidence on first‐episode patients, but less on patients with treatment‐resistant disorders, and the evidence was not clearly applicable to adolescents, older adults, or patients with multiple comorbid conditions. For the SGAs versus each other, there was evidence for all of the prioritized outcomes; however, the majority of the evidence on effectiveness (long‐term health outcomes) was limited to the older drugs. For FGAs versus SGAs, the outcomes were more limited, with little good‐quality evidence on effectiveness outcomes, such as function, quality of life, self‐harm, and mortality. There was little evidence on long‐term follow‐up (greater than 2 years). For SGAs compared with each other, the evidence applied only to outpatients, while almost half the studies of FGAs versus SGAs were conducted among inpatients.
Although study quality was not a key limitation, funding source may have been, because more than 80% of the studies were funded by the manufacturer of one of the drugs in the trial. Other limitations included variability in patient characteristics, which were often poorly reported, and variability in the specific outcomes selected for study and how they were measured or reported. Consensus on which outcomes are most important and how to best measure them is needed; for example, the primary outcome measure in the CATIE trials (time to discontinuation of drug), which was selected for well‐publicized reasons, was not prioritized by our expert panel. Although many of the older studies lacked general‐izability to the real‐life practice setting, because either the doses used were higher or lower than those used in practice today or the dose comparisons were unfair (e.g., a low dose of one drug versus a high dose of a comparator drug), our analysis of these issues as part of our network analyses indicated that more recent studies have fewer issues with dosing. In comparing drugs, an important limitation was that the typical dosing for some drugs has changed over time, with lower doses used in more recent studies of several older drugs. Also, the prior treatment experience of patients enrolled varied over time (fewer patients had prior FGA exposure or resistance in more recent studies). Evidence on the subgroups was limited by the small sample sizes, and most analyses were post hoc rather than either preplanned analyses or trials designed to address these subgroups as their primary objective. Although we limited our analyses to direct, head‐to‐head comparisons of drugs, the inclusion of indirect (e.g., placebo‐controlled trial) evidence may have led to erroneous conclusions (85, 86). The specific characteristics of enrolled patients, dosing, or other treatment considerations may have played a role in the results, particularly when the indirect evidence was based on studies conducted for marketing approval of a drug. An example of this situation may be seen with clozapine, which was typically found to be superior to all other antipsychotics among patients with treatment‐resistant disease. In contrast, we found that olanzapine and risperidone may also be useful, and we did not find clozapine to be highly superior. In related prior work, we found that older placebo‐controlled trials of clozapine enrolled patients with very severe symptoms, in whom a larger margin of change was likely to be seen with an effective treatment, and that clozapine dosing was much higher than is acceptable today (87).
Our findings are mainly compatible with other recent systematic reviews and meta‐analyses, which have varied in scope and focus (88, 89, 90). For example, a recent large network meta‐analysis (88) covered many of the same SGAs and outcomes as our review but excluded studies of patients with treatment‐resistant disease, a first episode, or with predominant negative symptoms. Importantly, many of the drugs included in the network meta‐analysis (88) are not available in the United States at this time or were identified as a drug not currently used to treat schizophrenia (54% of the drugs in the network). Inclusion of such a large amount of data that is not relevant to the current U.S. setting would influence the results. Other fairly recent reviews have focused on specific subpopulations of patients with schizophrenia (e.g., first episode or long duration studies only) and also have included drugs not available in the United States (89, 90). All of these reviews excluded the newer long‐acting injectable drugs, which were of key interest to inform APA guidelines. These scope issues are decisions that were made early in the review process; our review was intentionally broad in population and outcome criteria and specific to the needs of the APA for drug interventions studied. As required to perform review work for AHRQ, none of our review team had conflicts of interest to declare, whereas this was not true for these other recent reviews.
On the basis of the limitations identified here, several research recommendations can be made. Future studies should involve multiple newer SGA drugs (approved in the past 10 years); include comparable dosing with the most appropriate dosing titration methods for all drugs included; measure key health outcomes (including harms); have study durations of 3 to 5 years of follow‐up; incorporate the concept of recovery into study designs (i.e., inclusion of recovery as a primary outcome, with an a priori definition and criteria), with testing of duration of effect and discontinuation of drug treatment following remission; enroll patients who reflect real populations (e.g., older patients, multiple comorbidities, concomitant medications, severe disease); and prespecify subgroup analyses (e.g., women and racial‐ethnic groups).

CONCLUSIONS

Most of the comparative evidence has described older SGAs (clozapine, olanzapine, risperidone, quetiapine, and zipra‐sidone), with some evidence describing paliperidone and aripiprazole and newer long‐acting injectable formulations, and very little addressing newer SGAs approved in the past 10 years (asenapine, brexpiprazole, cariprazine, iloperidone, and lurasidone). Although none were superior on multiple high‐priority outcomes, among the SGAs, clozapine, olan‐zapine, and risperidone oral and LAI showed superior performance on more outcomes, and quetiapine and ziprasidone were not better on any outcome. On the basis of limited evidence, newer SGAs were not found to be superior to older SGAs. Compared with haloperidol, olanzapine, risperidone, ziprasidone, and aripiprazole performed similarly on benefit outcomes and resulted in lower incidence of adverse events or withdrawals.

Footnotes

This project was funded by the Agency for Healthcare Research and Quality (AHRQ), U.S. Department of Health and Human Services (DHHS) (290‐2015‐00009‐I).
AHRQ retains a license to display, reproduce, and distribute the data and the report from which the manuscript was derived under the terms of the agency's contract with the authors. These views represent the opinions of the authors and not necessarily those of the AHRQ or the DHHS.
The authors report no financial relationships with commercial interests.

Supplementary Material

File (rcp21012-sup-0001-suppl-data.pdf)
Supplementary material

REFERENCES

1.
Diagnostic and Statistical Manual of Mental Disorders, 5th ed. Washington, DC, American Psychiatric Association, 2013
2.
Tandon R, Gaebel W, Barch DM, et al: Definition and description of schizophrenia in the DSM‐5. Schizophr Res 2013; 150:3‐10
3.
McGrath J, Saha S, Chant D, et al: Schizophrenia: a concise overview of incidence, prevalence, and mortality. Epidemiol Rev 2008; 30: 67‐76
4.
Harding CM: Changes in schizophrenia across time: paradoxes, patterns and predictors; in Schizophrenia Into Later Life: Treatment, Research and Policy. Edited by Cohen CI. Arlington, VA, American Psychiatric Association, 2003
5.
Wils RS, Gotfredsen DR, Hjorthøj C, et al: Antipsychotic medication and remission of psychotic symptoms 10 years after a first‐episode psychosis. Schizophr Res 2017; 182:42‐48
6.
Keating D, McWilliams S, Schneider I, et al: Pharmacological guidelines for schizophrenia: a systematic review and comparison of recommendations for the first episode. BMJ Open 2017; 7: e013881‐e013881
7.
Remington G, Chong SA: Conventional versus novel antipsychotics: changing concepts and clinical implications. J Psychiatry Neurosci 1999; 24:431‐441
8.
Kane JM: Pharmacologic treatment of schizophrenia. Biol Psychiatry 1999; 46:1396‐1408
9.
Markowitz JS, Brown CS, Moore TR: Atypical antipsychotics. part I: pharmacology, pharmacokinetics, and efficacy. Ann Pharmacother 1999; 33:73‐85
10.
McDonagh M, Dana T, Selph S, et al: Treatments for Schizophrenia in Adults: A Systematic Review. Comparative Effectiveness Review no 198. AHRQ pub no 17(18)‐EHC031‐EF Rockville, MD, Agency for Healthcare Research and Quality, 2017
11.
Moher D, Liberati A, Tetzlaff J, et al: Preferred reporting items for systematic reviews and meta‐analyses: the PRISMA statement. BMJ 2009; 339:b2535
12.
Methods Guide for Effectiveness and Comparative Effectiveness Reviews. AHRQ Publication no 10(14)‐EHC063‐EF. Rockville MD, Agency for Healthcare Research and Quality, 2014.
13.
White CM, Ip S, McPheeters M, et al. Using existing systematic reviews to replace de novo processes in conducting comparative effectiveness reviews; in Methods Guide for Effectiveness and Comparative Effectiveness Reviews. Rockville, MD, Agency for Healthcare Research and Quality, 2008
14.
McDonagh MS, Jonas DE, Gartlehner G, et al: Methods for the drug effectiveness review project. BMC Med Res Methodol 2012; 12:140
15.
SheaBJ, Grimshaw JM, Wells GA, et al: Development of AMSTAR: a measurement tool to assess the methodological quality of systematic reviews. BMC Med Res Methodol 2007; 7:10
16.
Higgins JPT, Thompson SG: Quantifying heterogeneity in a metaanalysis. Stat Med 2002; 21:1539‐1558
17.
McDonagh M, Peterson K, Fu R, et al: Second Generation Anti‐psychotic Drugs. Final Update 4 Report. Portland, OR, Oregon Health & Science University, Pacific Northwest Evidence‐Based Practice Center for the Drug Effectiveness Review Project, 2013. https://www.ohsu.edu/sites/default/files/2019‐01/SGA_final‐update‐4‐report_Nov‐2013_version‐2.pdf
18.
Lu G, Ades AE: Combination of direct and indirect evidence in mixed treatment comparisons. Stat Med 2004; 23:3105‐3124
19.
Lu X, Cheng H, Song S, et al: A study of quetiapine and risperidone and clozapine in the treatment of schizophrenia. China and Foreign Medical Journal 2006; 4:62‐4
20.
Berkman ND, Lohr KN, Ansari MT, et al: Grading the strength of a body of evidence when assessing health care interventions: an EPC update. J Clin Epidemiol 2015; 68:1312‐1324
21.
Citrome L, Ota A, Nagamizu K, et al: The effect of brexpiprazole (OPC‐34712) and aripiprazole in adult patients with acute schizophrenia: results from a randomized, exploratory study. Int Clin Psychopharmacol 2016; 31:192‐201
22.
Detke HC, Weiden PJ, Llorca PM, et al: Comparison of olanzapine long‐acting injection and oral olanzapine: a 2‐year, randomized, open‐label study in outpatients with schizophrenia. J Clin Psy‐chopharmacol 2014; 34:426‐434
23.
Di Fiorino M, Montagnani G, Trespi G, et al: Extended‐release quetiapine fumarate (quetiapine XR) versus risperidone in the treatment of depressive symptoms in patients with schizoaffective disorder or schizophrenia: a randomized, open‐label, parallel‐group, flexible‐dose study. Int Clin Psychopharmacol 2014; 29:166‐176
24.
Durgam S, Starace A, Li D, et al: An evaluation of the safety and efficacy of cariprazine in patients with acute exacerbation of schizophrenia: a phase II, randomized clinical trial. Schizophr Res 2014; 152: 450‐457
25.
Fleischhacker WW, Sanchez R, Perry PP, et al: Aripiprazole once‐monthly for treatment of schizophrenia: double‐blind, randomised, non‐inferiority study. Br J Psychiatry 2014; 205:135‐144
26.
Green AI, Brunette MF, Dawson R, et al: Long‐acting injectable vs oral risperidone for schizophrenia and co‐occurring alcohol use disorder: a randomized trial. J Clin Psychiatry 2015; 76:1359‐1365
27.
Ishigooka J, Nakamura J, Fujii Y, et al: Efficacy and safety of aripiprazole once‐monthly in Asian patients with schizophrenia: a multicenter, randomized, double‐blind, non‐inferiority study versus oral aripiprazole. Schizophr Res 2015; 161:421‐428
28.
Koshikawa Y, Takekita Y, Kato M, et al: The comparative effects of risperidone long‐acting injection and paliperidone palmitate on social functioning in schizophrenia: a 6‐month, open‐label, randomized controlled pilot trial. Neuropsychobiology 2016; 73:35‐42
29.
Li H, Luo J, Wang C, et al: Efficacy and safety of aripiprazole in Chinese Han schizophrenia subjects: a randomized, double‐blind, active parallel‐controlled, multicenter clinical trial. Schizophr Res 2014; 157:112‐119
30.
Liu J, Sun J, Shen X, et al: Randomized controlled trial comparing changes in serum prolactin and weight among female patients with first‐episode schizophrenia over 12 months of treatment with risperidone or quetiapine. Shanghai Jingshen Yixue 2014; 26:88‐94
31.
Maat A, Cahn W, Gijsman HJ, et al: Open, randomized trial of the effects of aripiprazole versus risperidone on social cognition in schizophrenia. Eur Neuropsychopharmacol 2014; 24:575‐584
32.
Naber D, Hansen K, Forray C, et al: Qualify: a randomized head‐to‐head study of aripiprazole once‐monthly and paliperidone palmitate in the treatment of schizophrenia. Schizophr Res 2015; 168:498‐504
33.
Naber D, Peuskens J, Schwarzmann N, et al: Subjective well‐being in schizophrenia: a randomised controlled open‐label 12‐month non‐inferiority study comparing quetiapine XR with risperidone (RECOVER). Eur Neuropsychopharmacol 2013; 23:1257‐1269
34.
Németh G, Laszlovszky I, Czobor P, et al: Cariprazine versus ris‐peridone monotherapy for treatment of predominant negative symptoms in patients with schizophrenia: a randomised, doubleblind, controlled trial. Lancet 2017; 389:1103‐1113
35.
Parabiaghi A, Tettamanti M, D'Avanzo B, et al: Metabolic syndrome and drug discontinuation in schizophrenia: a randomized trial comparing aripiprazole olanzapine and haloperidol. Acta Psychiatr Scand 2016; 133:63‐75
36.
Park S, Yi KK, Kim MS, et al: Effects of ziprasidone and olanzapine on body composition and metabolic parameters: an open‐label comparative pilot study. Behav Brain Funct 2013; 9:27
37.
Robinson DG, Gallego JA, John M, et al: A randomized comparison of aripiprazole and risperidone for the acute treatment of first‐episode schizophrenia and related disorders: 3‐month outcomes. Schizophr Bull 2015; 41:1227‐1236
38.
Sanz‐Fuentenebro J, Taboada D, Palomo T, et al: Randomized trial of clozapine vs risperidone in treatment‐naïve first‐episode schizophrenia: results after one year. Schizophr Res 2013; 149:156‐161
39.
Savitz AJ, Xu H, Gopal S, et al: Efficacy and safety of paliperidone palmitate 3‐month formulation for patients with schizophrenia: a randomized, multicenter, double‐blind, noninferiority study. Int J Neuropsychopharmacol 2016; 19:pyw018
40.
Shoja Shafti S, Kaviani H: Quetiapine versus aripiprazole in the management of schizophrenia. Ther Adv Psychopharmacol 2015; 5: 166‐171
41.
Subotnik KL, Casaus LR, Ventura J, et al: Long‐acting injectable risperidone for relapse prevention and control of breakthrough symptoms after a recent first episode of schizophrenia. A randomized clinical trial. JAMA Psychiatry 2015; 72:822‐829
42.
Tybura P, Mak M, Samochowiec A, et al: The influence of anti‐psychotic therapy on the cognitive functions of schizophrenic patients [in Polish]. Psychiatr Pol 2013; 47:567‐578
43.
Tybura P, Trześniowska‐Drukala B, Bienkowski P, et al: Pharmacogenetics of adverse events in schizophrenia treatment: comparison study of ziprasidone, olanzapine and perazine. Psychiatry Res 2014; 219:261‐267
44.
Wani RA, Dar MA, Chandel RK, et al: Effects of switching from olanzapine to aripiprazole on the metabolic profiles of patients with schizophrenia and metabolic syndrome: a double‐blind, randomized, open‐label study. Neuropsychiatr Dis Treat 2015; 11:685‐693
45.
Abou‐Setta AM, Mousavi SS, Spooner C, et al: First‐Generation Versus Second‐Generation Antipsychotics in Adults: Comparative Effectiveness. Comparative effectiveness review No. 63. Pub no AHRQ‐12‐EHC054‐EF. Rockville, MD, Agency for Healthcare Research and Quality, 2012
46.
Hartling L, Abou‐Setta AM, Dursun S, et al: Antipsychotics in adults with schizophrenia: comparative effectiveness of first‐generation versus second‐generation medications: a systematic review and meta‐analysis. Ann Intern Med 2012; 157:498‐511
47.
Crespo‐Facorro B, Pérez‐Iglesias R, Mata I, et al: Effectiveness of haloperidol, risperidone and olanzapine in the treatment of firstepisode non‐affective psychosis: results of a randomized, flexible‐dose, open‐label 1‐year follow‐up comparison. J Psychopharmacol 2011; 25:744‐754
48.
San L, Arranz B, Perez V, et al: One‐year, randomized, open trial comparing olanzapine, quetiapine, risperidone and ziprasidone effectiveness in antipsychotic‐naive patients with a first‐episode psychosis. Psychiatry Res 2012; 200:693‐701
49.
Amr M, Lakhan SE, Sanhan S, et al: Efficacy and tolerability of quetiapine versus haloperidol in first‐episode schizophrenia: a randomized clinical trial. Int Arch Med 2013; 6:47
50.
McEvoy JP, Byerly M, Hamer RM, et al: Effectiveness of paliper‐idone palmitate vs haloperidol decanoate for maintenance treatment of schizophrenia: a randomized clinical trial. JAMA 2014; 311:1978‐1987
51.
Lieberman JA, Stroup TS, McEvoy JP, et al: Effectiveness of antipsychotic drugs in patients with chronic schizophrenia. N Engl J Med 2005; 353:1209‐1223
52.
McEvoy JP, Lieberman JA, Stroup TS, et al: Effectiveness of clo‐zapine versus olanzapine, quetiapine, and risperidone in patients with chronic schizophrenia who did not respond to prior atypical antipsychotic treatment. Am J Psychiatry 2006; 163:600‐610
53.
Stroup TS, Lieberman JA, McEvoy JP, et al: Effectiveness of olan‐zapine, quetiapine, and risperidone in patients with chronic schizophrenia after discontinuing perphenazine: a CATIE study. Am J Psychiatry 2007; 164:415‐427
54.
Stroup TS, Lieberman JA, McEvoy JP, et al: Effectiveness of olan‐zapine, quetiapine, risperidone, and ziprasidone in patients with chronic schizophrenia following discontinuation of a previous atypical antipsychotic. Am J Psychiatry 2006; 163:611‐622
55.
Stroup TS, Lieberman JA, McEvoy JP, et al: Results of phase 3 of the CATIE schizophrenia trial. Schizophr Res 2009; 107:1‐12
56.
Rouillon F, Eriksson L, Burba B, et al: Functional recovery results from the risperidone long‐acting injectable versus quetiapine relapse prevention trial (ConstaTRE). Acta Neuropsychiatr 2013; 25:297‐306
57.
Leucht S, Cipriani A, Spineli L, et al: Comparative efficacy and tolerability of 15 antipsychotic drugs in schizophrenia: a multiple‐treatments meta‐analysis. Lancet 2013; 382:951‐962
58.
A Multicenter, Open‐Label, Flexible‐Dose, Parallel‐Group Evaluation of the Cataractogenic Potential of Quetiapine Fumarate (Sero‐quel) and Risperidone (Risperdal) in the Long‐Term Treatment of Patients with Schizophrenia or Schizoaffective disorder [CLEARS]. Clinical Study Report Synopsis. AstraZeneca, 2010
59.
An 8‐Week, Multicenter, Double‐Blind, Randomized, Parallel‐Group, Placebo‐Controlled Study of the Efficacy and Safety of Quetiapine Fumarate (SEROQUEL) Extended‐Release in Children and Adolescent Subjects with Bipolar Depression. Clinical Study Report Synopsis D144AC00001. AstraZeneca, 2011
60.
Mullen J, Jibson MD, Sweitzer D: A comparison of the relative safety, efficacy, and tolerability of quetiapine and risperidone in outpatients with schizophrenia and other psychotic disorders: the quetiapine experience with safety and tolerability (QUEST) study. Clin Ther 2001; 23:1839‐1854
61.
Schoemaker J, Naber D, Vrijland P, et al: Long‐term assessment of asenapine vs olanzapine in patients with schizophrenia or schizoaffective disorder. Pharmacopsychiatry 2010; 43:138‐146
62.
Buchanan RW, Panagides J, Zhao J, et al: Asenapine versus olanzapine in people with persistent negative symptoms of schizophrenia. J Clin Psychopharmacol 2012; 32:36‐45
63.
Fleischhacker WW, Gopal S, Lane R, et al: A randomized trial of paliperidone palmitate and risperidone long‐acting injectable in schizophrenia. Int J Neuropsychopharmacol 2012; 15:107‐118
64.
Li H, Rui Q, Ning X, et al: A comparative study of paliperidone palmitate and risperidone long‐acting injectable therapy in schizophrenia. Prog Neuropsychopharmacol Biol Psychiatry 2011; 35: 1002‐1008
65.
Savitz AJ, Lane R, NuamahI, et al: Efficacy and safety of paliperidone extended release in adolescents with schizophrenia: a randomized, double‐blind study. J Am Acad Child Adolesc Psychiatry 2015; 54: 126‐137.e1.
66.
Meltzer HY, Alphs L, Green AI, et al: Clozapine treatment for suicidality in schizophrenia: International Suicide Prevention Trial (InterSePT). Arch Gen Psychiatry 2003; 60:82‐91
67.
Kiviniemi M, Suvisaari J, Koivumaa‐Honkanen H, et al: Antipsychotics and mortality in first‐onset schizophrenia: prospective Finnish register study with 5‐year follow‐up. Schizophr Res 2013; 150:274‐280
68.
Bitter I, Katona L, Zámbori J, et al: Comparative effectiveness of depot and oral second generation antipsychotic drugs in schizophrenia: a nationwide study in Hungary. Eur Neuropsychopharmacol 2013; 23:1383‐1390
69.
Pérez‐Iglesias R, Ortiz‐Garcia de la Foz V, Martínez García O, et al: Comparison of metabolic effects of aripiprazole, quetiapine and ziprasidone after 12 weeks of treatment in first treated episode of psychosis. Schizophr Res 2014; 159:90‐94
70.
Cuomo I, Kotzalidis GD, de Persis S, et al: Head‐to‐head comparison of 1‐year aripiprazole long‐acting injectable (LAI) versus paliperidone LAI in comorbid psychosis and substance use disorder: impact on clinical status, substance craving, and quality of life. Neuro‐psychiatr Dis Treat 2018; 14:1645‐1656
71.
Huang M, Yu L, Pan F, et al: A randomized, 13‐week study assessing the efficacy and metabolic effects of paliperidone palmitate injection and olanzapine in first‐episode schizophrenia patients. Prog Neuropsychopharmacol Biol Psychiatry 2018; 81:122‐130
72.
Kishimoto T, Robenzadeh A, Leucht C, et al: Long‐acting injectable vs oral antipsychotics for relapse prevention in schizophrenia: a meta‐analysis of randomized trials. Schizophr Bull 2014; 40:192‐213
73.
Ranasinghe I, Sin J: A systematic review of evidence‐based treatment for individuals with treatment‐resistant schizophrenia and a suboptimal response to clozapine monotherapy. Psychosis 2014; 6:253‐265
74.
Samara MT, Dold M, Gianatsi M, et al: Efficacy, acceptability, and tolerability of antipsychotics in treatment‐resistant schizophrenia: a network meta‐analysis. JAMA Psychiatry 2016; 73:199‐210
75.
Souza JS, Kayo M, Tassell I, et al: Efficacy of olanzapine in comparison with clozapine for treatment‐resistant schizophrenia: evidence from a systematic review and meta‐analyses. CNS Spectr 2013; 18:82‐89
76.
Zhang J‐P, Gallego JA, Robinson DG, et al: Efficacy and safety of individual second‐generation vs first‐generation antipsychotics in first‐episode psychosis: a systematic review and meta‐analysis. Int J Neuropsychopharmacol 2013; 16:1205‐1218
77.
Fusar‐Poli P, Kempton MJ, Rosenheck RA: Efficacy and safety of second‐generation long‐acting injections in schizophrenia: a metaanalysis of randomized‐controlled trials. Int Clin Psychopharmacol 2013; 28:57‐66
78.
Soares‐Weiser K, Béchard‐Evans L, Lawson AH, et al: Time to all‐cause treatment discontinuation of olanzapine compared to other antipsychotics in the treatment of schizophrenia: a systematic review and meta‐analysis. Eur Neuropsychopharmacol 2013; 23:118‐125
79.
Tonin FS, Piazza T, Wiens A, et al: Adverse events and treatment failure leading to discontinuation of recently approved antipsychotic drugs in schizophrenia: a network meta‐analysis. Schizophr Res 2015; 169:483‐485
80.
Asenjo Lobos C, Komossa K, Rummel‐Kluge C, et al: Clozapine versus other atypical antipsychotics for schizophrenia. Cochrane Database Syst Rev 2010; 11:CD006633
81.
Asmal L, Flegar SJ, Wang J, et al: Quetiapine versus other atypical antipsychotics for schizophrenia. Cochrane Database Syst Rev 2013; 11:CD006625
82.
Ayub M, Saeed K, Munshi TA, et al: Clozapine for psychotic disorders in adults with intellectual disabilities. Cochrane Database Syst Rev 2015; 9:CD010625
83.
Chou R, Carson S, Chan BK: Gabapentin versus tricyclic antide‐pressants for diabetic neuropathy and post‐herpetic neuralgia: discrepancies between direct and indirect meta‐analyses of randomized controlled trials. J Gen Intern Med 2009; 24:178‐188
84.
Chou R, Fu R, Huffman LH, et al: Initial highly‐active antiretroviral therapy with a protease inhibitor versus a non‐nucleoside reverse transcriptase inhibitor: discrepancies between direct and indirect meta‐analyses. Lancet 2006; 368:1503‐1515
85.
Trinquart L, Attiche N, Bafeta A, et al: Uncertainty in treatment rankings: reanalysis of network meta‐analyses of randomized trials. Ann Intern Med 2016; 164:666‐673
86.
Chou R, Carson S, Chan BK: Pegylated interferons for chronic hepatitis C virus infection: an indirect analysis of randomized trials. J Viral Hepat 2008; 15:551‐570
87.
McDonagh M, Peterson K, Freeman M, et al: Drug Class Review: Atypical Antipsychotic Drugs, Update 1 Portland, OR, Oregon Health & Science University, Pacific Northwest Evidence‐Based Practice Center for the Drug Effectiveness Review Project 2006. https://www.ohsu.edu/evidence-based-practice-center/derp-reports#section-114911. Accessed December, 1, 2019
88.
Huhn M, Nikolakopoulou A, Schneider‐Thoma J, et al: Comparative efficacy and tolerability of 32 oral antipsychotics for the acute treatment of adults with multi‐episode schizophrenia: a systematic review and network meta‐analysis. Lancet 2019; 394:939‐951
89.
Kishimoto T, Hagi K, Nitta M, et al: Long‐term effectiveness of oral second‐generation antipsychotics in patients with schizophrenia and related disorders: a systematic review and meta‐analysis of direct head‐to‐head comparisons. World Psychiatry 2019; 18:208‐224
90.
Zhu Y, Krause M, Huhn M, et al: Antipsychotic drugs for the acute treatment of patients with a first episode of schizophrenia: a systematic review with pairwise and network meta‐analyses. Lancet Psychiatry 2017; 4:694‐705

Information & Authors

Information

Published In

Go to Psychiatric Research and Clinical Practice
Psychiatric Research and Clinical Practice
Pages: 76 - 87

History

Received: 21 January 2020
Revision received: 14 February 2020
Revision received: 13 March 2020
Accepted: 27 March 2020
Published online: 29 June 2020
Published in print: December 2020

Authors

Affiliations

Marian S. McDonagh, Pharm.D.
Pacific Northwest Evidence‐Based Practice Center, Portland, Oregon (M. S. McDonagh, T. Dana, S. Selph, A. Cantor, C. Bougatsos, I. Blazina, S. Grusing, R. Fu); Department of Medical Informatics and Clinical Epidemiology (M. S. McDonagh, T. Dana, S. Selph, A. Cantor, C. Bougatsos, I. Blazina, S. Grusing); Department of Family Medicine (A. Cantor); School of Public Health (R. Fu); Department of Psychiatry (D. W. Haupt); Oregon Health and Science University, Portland (E. B. Devine); Department of Pharmacy, and Comparative Health Outcomes Police and Economics Institute, University of Washington, Seattle (E. B. Devine)
Tracy Dana, M.L.S.
Pacific Northwest Evidence‐Based Practice Center, Portland, Oregon (M. S. McDonagh, T. Dana, S. Selph, A. Cantor, C. Bougatsos, I. Blazina, S. Grusing, R. Fu); Department of Medical Informatics and Clinical Epidemiology (M. S. McDonagh, T. Dana, S. Selph, A. Cantor, C. Bougatsos, I. Blazina, S. Grusing); Department of Family Medicine (A. Cantor); School of Public Health (R. Fu); Department of Psychiatry (D. W. Haupt); Oregon Health and Science University, Portland (E. B. Devine); Department of Pharmacy, and Comparative Health Outcomes Police and Economics Institute, University of Washington, Seattle (E. B. Devine)
Shelley Selph, M.D., M.P.H.
Pacific Northwest Evidence‐Based Practice Center, Portland, Oregon (M. S. McDonagh, T. Dana, S. Selph, A. Cantor, C. Bougatsos, I. Blazina, S. Grusing, R. Fu); Department of Medical Informatics and Clinical Epidemiology (M. S. McDonagh, T. Dana, S. Selph, A. Cantor, C. Bougatsos, I. Blazina, S. Grusing); Department of Family Medicine (A. Cantor); School of Public Health (R. Fu); Department of Psychiatry (D. W. Haupt); Oregon Health and Science University, Portland (E. B. Devine); Department of Pharmacy, and Comparative Health Outcomes Police and Economics Institute, University of Washington, Seattle (E. B. Devine)
Emily B. Devine, Pharm.D., Ph.D.
Pacific Northwest Evidence‐Based Practice Center, Portland, Oregon (M. S. McDonagh, T. Dana, S. Selph, A. Cantor, C. Bougatsos, I. Blazina, S. Grusing, R. Fu); Department of Medical Informatics and Clinical Epidemiology (M. S. McDonagh, T. Dana, S. Selph, A. Cantor, C. Bougatsos, I. Blazina, S. Grusing); Department of Family Medicine (A. Cantor); School of Public Health (R. Fu); Department of Psychiatry (D. W. Haupt); Oregon Health and Science University, Portland (E. B. Devine); Department of Pharmacy, and Comparative Health Outcomes Police and Economics Institute, University of Washington, Seattle (E. B. Devine)
Amy Cantor, M.D., M.P.H.
Pacific Northwest Evidence‐Based Practice Center, Portland, Oregon (M. S. McDonagh, T. Dana, S. Selph, A. Cantor, C. Bougatsos, I. Blazina, S. Grusing, R. Fu); Department of Medical Informatics and Clinical Epidemiology (M. S. McDonagh, T. Dana, S. Selph, A. Cantor, C. Bougatsos, I. Blazina, S. Grusing); Department of Family Medicine (A. Cantor); School of Public Health (R. Fu); Department of Psychiatry (D. W. Haupt); Oregon Health and Science University, Portland (E. B. Devine); Department of Pharmacy, and Comparative Health Outcomes Police and Economics Institute, University of Washington, Seattle (E. B. Devine)
Christina Bougatsos, M.P.H.
Pacific Northwest Evidence‐Based Practice Center, Portland, Oregon (M. S. McDonagh, T. Dana, S. Selph, A. Cantor, C. Bougatsos, I. Blazina, S. Grusing, R. Fu); Department of Medical Informatics and Clinical Epidemiology (M. S. McDonagh, T. Dana, S. Selph, A. Cantor, C. Bougatsos, I. Blazina, S. Grusing); Department of Family Medicine (A. Cantor); School of Public Health (R. Fu); Department of Psychiatry (D. W. Haupt); Oregon Health and Science University, Portland (E. B. Devine); Department of Pharmacy, and Comparative Health Outcomes Police and Economics Institute, University of Washington, Seattle (E. B. Devine)
Ian Blazina, M.P.H.
Pacific Northwest Evidence‐Based Practice Center, Portland, Oregon (M. S. McDonagh, T. Dana, S. Selph, A. Cantor, C. Bougatsos, I. Blazina, S. Grusing, R. Fu); Department of Medical Informatics and Clinical Epidemiology (M. S. McDonagh, T. Dana, S. Selph, A. Cantor, C. Bougatsos, I. Blazina, S. Grusing); Department of Family Medicine (A. Cantor); School of Public Health (R. Fu); Department of Psychiatry (D. W. Haupt); Oregon Health and Science University, Portland (E. B. Devine); Department of Pharmacy, and Comparative Health Outcomes Police and Economics Institute, University of Washington, Seattle (E. B. Devine)
Sara Grusing, B.A.
Pacific Northwest Evidence‐Based Practice Center, Portland, Oregon (M. S. McDonagh, T. Dana, S. Selph, A. Cantor, C. Bougatsos, I. Blazina, S. Grusing, R. Fu); Department of Medical Informatics and Clinical Epidemiology (M. S. McDonagh, T. Dana, S. Selph, A. Cantor, C. Bougatsos, I. Blazina, S. Grusing); Department of Family Medicine (A. Cantor); School of Public Health (R. Fu); Department of Psychiatry (D. W. Haupt); Oregon Health and Science University, Portland (E. B. Devine); Department of Pharmacy, and Comparative Health Outcomes Police and Economics Institute, University of Washington, Seattle (E. B. Devine)
Rongwei Fu, Ph.D.
Pacific Northwest Evidence‐Based Practice Center, Portland, Oregon (M. S. McDonagh, T. Dana, S. Selph, A. Cantor, C. Bougatsos, I. Blazina, S. Grusing, R. Fu); Department of Medical Informatics and Clinical Epidemiology (M. S. McDonagh, T. Dana, S. Selph, A. Cantor, C. Bougatsos, I. Blazina, S. Grusing); Department of Family Medicine (A. Cantor); School of Public Health (R. Fu); Department of Psychiatry (D. W. Haupt); Oregon Health and Science University, Portland (E. B. Devine); Department of Pharmacy, and Comparative Health Outcomes Police and Economics Institute, University of Washington, Seattle (E. B. Devine)
Daniel W. Haupt, M.D.
Pacific Northwest Evidence‐Based Practice Center, Portland, Oregon (M. S. McDonagh, T. Dana, S. Selph, A. Cantor, C. Bougatsos, I. Blazina, S. Grusing, R. Fu); Department of Medical Informatics and Clinical Epidemiology (M. S. McDonagh, T. Dana, S. Selph, A. Cantor, C. Bougatsos, I. Blazina, S. Grusing); Department of Family Medicine (A. Cantor); School of Public Health (R. Fu); Department of Psychiatry (D. W. Haupt); Oregon Health and Science University, Portland (E. B. Devine); Department of Pharmacy, and Comparative Health Outcomes Police and Economics Institute, University of Washington, Seattle (E. B. Devine)

Notes

Send correspondence to Dr. McDonagh ([email protected])

Metrics & Citations

Metrics

Citations

Export Citations

If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.

For more information or tips please see 'Downloading to a citation manager' in the Help menu.

Format
Citation style
Style
Copy to clipboard

There are no citations for this item

View Options

View options

PDF/ePub

View PDF/ePub

Get Access

Login options

Already a subscriber? Access your subscription through your login credentials or your institution for full access to this article.

Personal login Institutional Login Open Athens login

Not a subscriber?

Subscribe Now / Learn More

PsychiatryOnline subscription options offer access to the DSM-5-TR® library, books, journals, CME, and patient resources. This all-in-one virtual library provides psychiatrists and mental health professionals with key resources for diagnosis, treatment, research, and professional development.

Need more help? PsychiatryOnline Customer Service may be reached by emailing [email protected] or by calling 800-368-5777 (in the U.S.) or 703-907-7322 (outside the U.S.).

Media

Figures

Other

Tables

Share

Share

Share article link

Share