Risperidone versus placebo for schizophrenia

A Long-Term Safety and Tolerability Study of TV-46000 for Subcutaneous Use in Patients with Schizophrenia: A Phase 3, Randomized, Double-Blinded Clinical Trial

BACKGROUND

TV-46000 is a long-acting subcutaneous antipsychotic (LASCA) formulation of risperidone that is approved by the United States Food and Drug Administration for the treatment of schizophrenia in adults. In the phase 3, randomized, double-blind RIsperidone Subcutaneous Extended-release (RISE) study, TV-46000 once monthly (q1m) and once every 2 months (q2m) significantly prolonged time to impending relapse compared with placebo [5.0-fold (q1m) and 2.7-fold (q2m)]. This phase 3, randomized, double-blind Safety in Humans of TV-46000 subcutaneous INjection Evaluation (SHINE) study was designed to evaluate the long-term safety, tolerability, and exposure of TV-46000 in schizophrenia.

METHODS

Patients who completed RISE without relapse (rollover) or who were newly recruited (de novo) were eligible for the SHINE study. Patients were initially stabilized on oral risperidone for 12 weeks (completed in RISE for rollover, or in SHINE for de novo). Patients in the de novo cohort and patients who received placebo in RISE were randomized 1:1 in SHINE to receive TV-46000 q1m or q2m for up to 56 weeks. Primary endpoint for SHINE was frequency of reported adverse events (AEs); event rates [ER; events per 100 patient-years (PYs)] were calculated for each AE by patients upon general questioning.

RESULTS

Overall, 336 patients were randomized in SHINE [TV-46000 q1m, n = 174; TV-46000 q2m, n = 162; of these, de novo, n = 109 and rollover, n = 227 (n = 172 patients were treated and n = 55 received placebo)]. A total of 334 patients were evaluated for safety [q1m, n = 172 (PY = 97.8); q2m, n = 162 (PY = 104.5)]. Proportions of patients (ER) with ≥ 1 AE and ≥ 1 treatment-related AE were 37% (180.0) and 21% (84.9) for TV-46000 q1m and 46% (157.9) and 20% (70.8) for TV-46000 q2m, respectively. Frequent treatment-related AEs [≥ 3% of patients in either group; proportion of patients (ER)] were injection site pain [q1m, 5% (24.5); q2m, 4% (22.0)] and injection site nodule [q1m, 2% (9.2); q2m, 6% (12.4)]. The proportions of patients with serious AEs was 5% for TV-46000 q1m and 7% for TV-46000 q2m; serious AEs reported for ≥ 2 patients overall were worsening schizophrenia [q1m, n = 1 (< 1%; ER, 1.02); q2m, n = 2 (1%; ER, 1.91)] and hyperglycemia [q1m, n = 1 (< 1%; ER, 1.02); q2m, n = 1 (< 1%; ER, 0.96)]. Of three reported deaths, none were related to treatment. Overall, eight patients discontinued treatment because of AEs. Similar or somewhat lower rates of AEs were reported for patients who rolled over from TV-46000 treatment compared with those who had no prior TV-46000 treatment (de novo and placebo rollover). Most AEs related to injection site reactions were mild; no patient had a severe reaction.

CONCLUSION

Results from this long-term safety study add to the favorable safety profiles of TV-46000 q1m and q2m, consistent with other formulations of risperidone and previous studies with TV-46000.

REGISTRATION

ClinicalTrials.gov, NCT03893825; 27 March 2019.

Benefits and harms of Risperidone and Paliperidone for treatment of patients with schizophrenia or bipolar disorder: a meta-analysis involving individual participant data and clinical study reports

BACKGROUND

Schizophrenia and bipolar disorder are severe mental illnesses which are highly prevalent worldwide. Risperidone and Paliperidone are treatments for either illnesses, but their efficacy compared to other antipsychotics and growing reports of hormonal imbalances continue to raise concerns. As existing evidence on both antipsychotics are solely based on aggregate data, we aimed to assess the benefits and harms of Risperidone and Paliperidone in the treatment of patients with schizophrenia or bipolar disorder, using individual participant data (IPD), clinical study reports (CSRs) and publicly available sources (journal publications and trial registries).

METHODS

We searched MEDLINE, Central, EMBASE and PsycINFO until December 2020 for randomised placebo-controlled trials of Risperidone, Paliperidone or Paliperidone palmitate in patients with schizophrenia or bipolar disorder. We obtained IPD and CSRs from the Yale University Open Data Access project. The primary outcome Positive and Negative Syndrome Scale (PANSS) score was analysed using one-stage IPD meta-analysis. Random-effect meta-analysis of harm outcomes involved methods for coping with rare events. Effect-sizes were compared across all available data sources using the ratio of means or relative risk. We registered our review on PROSPERO, CRD42019140556.

RESULTS

Of the 35 studies, IPD meta-analysis involving 22 (63%) studies showed a significant clinical reduction in the PANSS in patients receiving Risperidone (mean difference - 5.83, 95% CI - 10.79 to - 0.87, I2 = 8.5%, n = 4 studies, 1131 participants), Paliperidone (- 6.01, 95% CI - 8.7 to - 3.32, I2 = 4.3%, n = 13, 3821) and Paliperidone palmitate (- 7.89, 95% CI - 12.1 to - 3.69, I2 = 2.9%, n = 5, 2209). CSRs reported nearly two times more adverse events (4434 vs. 2296 publication, relative difference (RD) = 1.93, 95% CI 1.86 to 2.00) and almost 8 times more serious adverse events (650 vs. 82; RD = 7.93, 95% CI 6.32 to 9.95) than the journal publications. Meta-analyses of individual harms from CSRs revealed a significant increased risk among several outcomes including extrapyramidal disorder, tardive dyskinesia and increased weight. But the ratio of relative risk between the different data sources was not significant. Three treatment-related gynecomastia events occurred, and these were considered mild to moderate in severity.

CONCLUSION

IPD meta-analysis conclude that Risperidone and Paliperidone antipsychotics had a small beneficial effect on reducing PANSS score over 9 weeks, which is more conservative than estimates from reviews based on journal publications. CSRs also contained significantly more data on harms that were unavailable in journal publications or trial registries. Sharing of IPD and CSRs are necessary when performing meta-analysis on the efficacy and safety of antipsychotics.

Schizophrenia Treatment with Second-Generation Antipsychotics: A Multi-Country Comparison of the Costs of Cardiovascular and Metabolic Adverse Events and Weight Gain

PURPOSE

Cardiovascular and metabolic adverse events are costly to treat, and their incidence is increased amongst people with schizophrenia, with different rates observed for second-generation antipsychotics. To inform treatment choice, this study sought to estimate the lifetime costs associated with antipsychotic choice, and how these costs varied across European countries.

METHODS

Systematic searches were conducted to identify evidence on effectiveness and costs. A Markov model was developed to assess the costs of ten antipsychotics: aripiprazole, brexpiprazole, cariprazine, lumateperone, lurasidone, olanzapine, paliperidone, quetiapine, risperidone and ziprasidone. Costs were obtained for seven countries: Italy, Hungary, France, Slovenia, Spain, Sweden and the UK. The costs considered were adverse events (including diabetes, myocardial infarction, stroke and weight gain), drug costs, relapse, treatment discontinuation and schizophrenia management. Two adult populations were modelled; initiating either acute or maintenance treatment, with a lifetime horizon for both.

RESULTS

Lurasidone was associated with the lowest lifetime costs amongst patients initiating acute treatment compared to all other atypical antipsychotics considered. The second lowest costs were for ziprasidone. These results were observed for all seven countries. The main drivers of cost differences were rates of diabetes and cardiovascular diseases, which were lowest for lurasidone, followed by ziprasidone then lumateperone. Costs for managing weight gain were lowest for lurasidone and ziprasidone. Similar results were observed for patients initiating maintenance treatment.

CONCLUSION

Diabetes and cardiovascular events are large drivers of lifetime costs for people with schizophrenia. Lurasidone is predicted to have the lowest rates of these adverse events, and so the lowest costs amongst patients initiating acute treatment in seven European countries compared to nine other antipsychotics. Future research should investigate the individual costs of relapse management, including differences in the costs and proportions of hospitalizations.

Regulation of Reactive Oxygen Species-Mediated Damage in the Pathogenesis of Schizophrenia

The biochemical integrity of the brain is paramount to the function of the central nervous system, and oxidative stress is a key contributor to cerebral biochemical impairment. Oxidative stress, which occurs when an imbalance arises between the production of reactive oxygen species (ROS) and the efficacy of the antioxidant defense mechanism, is believed to play a role in the pathophysiology of various brain disorders. One such disorder, schizophrenia, not only causes lifelong disability but also induces severe emotional distress; however, because of its onset in early adolescence or adulthood and its progressive development, consuming natural antioxidant products may help regulate the pathogenesis of schizophrenia. Therefore, elucidating the functions of ROS and dietary antioxidants in the pathogenesis of schizophrenia could help formulate improved therapeutic strategies for its prevention and treatment. This review focuses specifically on the roles of ROS and oxidative damage in the pathophysiology of schizophrenia, as well as the effects of nutrition, antipsychotic use, cognitive therapies, and quality of life on patients with schizophrenia. By improving our understanding of the effects of various nutrients on schizophrenia, it may become possible to develop nutritional strategies and supplements to treat the disorder, alleviate its symptoms, and facilitate long-term recovery.

Psychological interventions for psychosis in adolescents

BACKGROUND

Psychosis is an illness characterised by alterations in thoughts and perceptions resulting in delusions and hallucinations. Psychosis is rare in adolescents but can have serious consequences. Antipsychotic medications are the mainstay treatment, and have been shown to be effective. However, there is emerging evidence on psychological interventions such as cognitive remediation therapy, psycho-education, family therapy and group psychotherapy that may be useful for adolescents with psychosis.

OBJECTIVES

To assess the effects of various psychological interventions for adolescents with psychosis.

SEARCH METHODS

We searched the Cochrane Schizophrenia Group's study-based Register of Trials including clinical trials registries (latest, 8 March 2019).

SELECTION CRITERIA

All randomised controlled trials comparing various psychological interventions with treatment-as-usual or other psychological treatments for adolescents with psychosis. For analyses, we included trials meeting our inclusion criteria and reporting useable data.

DATA COLLECTION AND ANALYSIS

We independently and reliably screened studies and we assessed risk of bias of the included studies. For dichotomous data, we calculated risk ratios (RRs) and 95% confidence intervals (CIs) on an intention-to-treat basis. For continuous data, we used mean differences (MDs) and the 95% CIs. We used a random-effects model for analyses. We created a 'Summary of findings' table using GRADE.

MAIN RESULTS

The current review includes 7 studies (n = 319) assessing a heterogenous group of psychological interventions with variable risk of bias. Adverse events were not reported by any of the studies. None of the studies was sponsored by industry. Below, we summarise the main results from four of six comparisons, and the certainty of these results (based on GRADE). All scale scores are average endpoint scores. Cognitive Remediation Therapy (CRT) + Treatment-as-Usual (TAU) versus TAU Two studies compared adding CRT to participants' TAU with TAU alone. Global state (CGAS, high = good) was reported by one study. There was no clear difference between treatment groups (MD -4.90, 95% CI -11.05 to 1.25; participants = 50; studies = 1, very low-certainty). Mental state (PANSS, high = poor) was reported by one study. Scores were clearly lower in the TAU group (MD 8.30, 95% CI 0.46 to 16.14; participants = 50; studies = 1; very low-certainty). Clearly more participants in the CRT group showed improvement in cognitive functioning (Memory digit span test) compared to numbers showing improvement in the TAU group (1 study, n = 31, RR 0.58, 95% CI 0.37 to 0.89; very low-certainty). For global functioning (VABS, high = good), our analysis of reported scores showed no clear difference between treatment groups (MD 5.90, 95% CI -3.03 to 14.83; participants = 50; studies = 1; very low-certainty). The number of participants leaving the study early from each group was similar (RR 0.93, 95% CI 0.32 to 2.71; participants = 91; studies = 2; low-certainty). Group Psychosocial Therapy (GPT) + TAU versus TAU One study assessed the effects of adding GPT to participants' usual medication. Global state scores (CGAS, high = good) were clearly higher in the GPT group (MD 5.10, 95% CI 1.35 to 8.85; participants = 56; studies = 1; very low-certainty) but there was little or no clear difference between groups for mental state scores (PANSS, high = poor, MD -4.10, 95% CI -8.28 to 0.08; participants = 56; studies = 1, very low-certainty) and no clear difference between groups for numbers of participants leaving the study early (RR 0.43, 95% CI 0.15 to 1.28; participants = 56; studies = 1; very low-certainty). Cognitive Remediation Programme (CRP) + Psychoeducational Treatment Programme (PTP) versus PTP One study assessed the effects of combining two types psychological interventions (CRP + PTP) with PTP alone. Global state scores (GAS, high = good) were not clearly different (MD 1.60, 95% CI -6.48 to 9.68; participants = 25; studies = 1; very low-certainty), as were mental state scores (BPRS total, high = poor, MD -5.40, 95% CI -16.42 to 5.62; participants = 24; studies = 1; very low-certainty), and cognitive functioning scores (SPAN-12, high = good, MD 2.40, 95% CI -2.67 to 7.47; participants = 25; studies = 1; very low-certainty). Psychoeducational (PE) + Multifamily Treatment (MFT) Versus Nonstructured Group Therapy (NSGT, all long-term) One study compared (PE + MFT) with NSGT. Analysis of reported global state scores (CGAS, high = good, MD 3.38, 95% CI -4.87 to 11.63; participants = 49; studies = 1; very low-certainty) and mental state scores (PANSS total, high = poor, MD -8.23, 95% CI -17.51 to 1.05; participants = 49; studies = 1; very low-certainty) showed no clear differences. The number of participants needing hospital admission (RR 0.84, 95% CI 0.36 to 1.96; participants = 49; studies = 1) and the number of participants leaving the study early from each group were also similar (RR 0.52, 95% CI 0.10 to 2.60; participants = 55; studies = 1; low-certainty).

AUTHORS' CONCLUSIONS

Most of our estimates of effect for our main outcomes are equivocal. An effect is suggested for only four outcomes in the SOF tables presented. Compared to TAU, CRT may have a positive effect on cognitive functioning, however the same study reports data suggesting TAU may have positive effect on mental state. Another study comparing GPT with TAU reports data suggesting GPT may have a positive effect on global state. However, the estimate of effects for all the main outcomes in our review should be viewed with considerable caution as they are based on data from a small number of studies with variable risk of bias. Further data could change these results and larger and better quality studies are needed before any firm conclusions regarding the effects of psychological interventions for adolescents with psychosis can be made.

Effectiveness of Proprioceptive Neuromuscular Facilitation on Pain Intensity and Functional Disability in Patients with Low Back Pain: A Systematic Review and Meta-Analysis

BACKGROUND

This systematic review aimed to investigate the effectiveness of proprioceptive neuromuscular facilitation (PNF) training on back pain intensity and functional disability in people with low back pain (LBP).

METHODS

Totally, five electronic databases, including PubMed/Medline (NLM), Scopus, Google Scholar, PEDro, and Cochrane Central Register of Controlled Clinical Trials were searched up to October 31, 2018. Clinical trials with a concurrent comparison group (s) that compared the effectiveness of PNF training with any other physical therapy intervention were selected. Publication language was restricted to English language articles. Methodologic quality was assessed using the PEDro scale. The measures of continuous variables were summarized as Hedges's g.

RESULTS

In total, 20 eligible trials were identified with 965 LBP patients. A large effect size (standardized mean difference [SMD]=-2.14, 95% confidence interval [CI]=3.23 to -1.05) and significant effect were observed favoring the use of PNF training to alleviate back pain intensity in patients with LBP. Moreover, large effect size and the significant result were also determined for the effect of PNF training on functional disability improvement (SMD=-2.68, 95% CI=-3.36 to -2.00) in population with LBP. A qualitative synthesis of results indicated that PNF training can significantly improve sagittal spine ROM. Statistical heterogeneity analysis showed that there was considerable statistical heterogeneity among the selected trials for the primary outcomes (I2 ≥ 86.6%).

CONCLUSION

There is a low quality of evidence and weak strength of recommendation that PNF training has positive effects on back pain and disability in LBP people. Further high-quality randomized clinical trials regarding long-term effects of PNF training versus validated control intervention in a clinical setting is recommendable.

Cognitive-behavioural therapy for clozapine-resistant schizophrenia: the FOCUS RCT

BACKGROUND

Clozapine (clozaril, Mylan Products Ltd) is a first-choice treatment for people with schizophrenia who have a poor response to standard antipsychotic medication. However, a significant number of patients who trial clozapine have an inadequate response and experience persistent symptoms, called clozapine-resistant schizophrenia (CRS). There is little evidence regarding the clinical effectiveness of pharmacological or psychological interventions for this population.

OBJECTIVES

To evaluate the clinical effectiveness and cost-effectiveness of cognitive-behavioural therapy (CBT) for people with CRS and to identify factors predicting outcome.

DESIGN

The Focusing on Clozapine Unresponsive Symptoms (FOCUS) trial was a parallel-group, randomised, outcome-blinded evaluation trial. Randomisation was undertaken using permuted blocks of random size via a web-based platform. Data were analysed on an intention-to-treat (ITT) basis, using random-effects regression adjusted for site, age, sex and baseline symptoms. Cost-effectiveness analyses were carried out to determine whether or not CBT was associated with a greater number of quality-adjusted life-years (QALYs) and higher costs than treatment as usual (TAU).

SETTING

Secondary care mental health services in five cities in the UK.

PARTICIPANTS

People with CRS aged ≥ 16 years, with an International Classification of Diseases, Tenth Revision (ICD-10) schizophrenia spectrum diagnoses and who are experiencing psychotic symptoms.

INTERVENTIONS

Individual CBT included up to 30 hours of therapy delivered over 9 months. The comparator was TAU, which included care co-ordination from secondary care mental health services.

MAIN OUTCOME MEASURES

The primary outcome was the Positive and Negative Syndrome Scale (PANSS) total score at 21 months and the primary secondary outcome was PANSS total score at the end of treatment (9 months post randomisation). The health benefit measure for the economic evaluation was the QALY, estimated from the EuroQol-5 Dimensions, five-level version (EQ-5D-5L), health status measure. Service use was measured to estimate costs.

RESULTS

Participants were allocated to CBT (n = 242) or TAU (n = 245). There was no significant difference between groups on the prespecified primary outcome [PANSS total score at 21 months was 0.89 points lower in the CBT arm than in the TAU arm, 95% confidence interval (CI) -3.32 to 1.55 points; p = 0.475], although PANSS total score at the end of treatment (9 months) was significantly lower in the CBT arm (-2.40 points, 95% CI -4.79 to -0.02 points; p = 0.049). CBT was associated with a net cost of £5378 (95% CI -£13,010 to £23,766) and a net QALY gain of 0.052 (95% CI 0.003 to 0.103 QALYs) compared with TAU. The cost-effectiveness acceptability analysis indicated a low likelihood that CBT was cost-effective, in the primary and sensitivity analyses (probability < 50%). In the CBT arm, 107 participants reported at least one adverse event (AE), whereas 104 participants in the TAU arm reported at least one AE (odds ratio 1.09, 95% CI 0.81 to 1.46; p = 0.58).

CONCLUSIONS

Cognitive-behavioural therapy for CRS was not superior to TAU on the primary outcome of total PANSS symptoms at 21 months, but was superior on total PANSS symptoms at 9 months (end of treatment). CBT was not found to be cost-effective in comparison with TAU. There was no suggestion that the addition of CBT to TAU caused adverse effects. Future work could investigate whether or not specific therapeutic techniques of CBT have value for some CRS individuals, how to identify those who may benefit and how to ensure that effects on symptoms can be sustained.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN99672552.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 7. See the NIHR Journals Library website for further project information.

Randomized, double-blind, 6-week non-inferiority study of lurasidone and risperidone for the treatment of schizophrenia

AIM

The aim of the present study was to evaluate the efficacy and safety of lurasidone for the treatment of Chinese schizophrenic patients.

METHODS

Hospitalized schizophrenia patients aged 18-65 were randomized to 6 weeks of double-blind, double-dummy, flexible-dose treatment with lurasidone (40 or 80 mg/day) or risperidone (2, 4 or 6 mg/day). Efficacy was evaluated using a non-inferiority comparison of lurasidone relative to risperidone based on week 6 change in the Positive and Negative Syndrome Scale (PANSS) total score. Safety assessments included adverse events, clinical laboratory measures, and electrocardiograms.

RESULTS

Four hundred and forty-four patients were screened to obtain an intent-to-treat sample of 384 patients, of whom 54 patients discontinued treatment prior to 6 weeks. Lurasidone met the criteria for non-inferiority versus risperidone on the PANSS total score. Adjusted mean (SE) change at week 6 on the PANSS total score was -31.2 (1.0) and -34.9 (1.0) in the lurasidone and risperidone group, respectively. The mean difference score was 3.7, and the upper boundary of the 95%-confidence interval (1.0-6.3) was less than the prespecified margin of 7.0. No clinically meaningful between-treatment group differences were evident on secondary efficacy measures, including PANSS positive, PANSS negative, Clinical Global Impression scale - Severity, and Calgary Depression Scale for Schizophrenia scales. The incidence of adverse events was lower for lurasidone vs risperidone for extrapyramidal symptoms (17.0% vs 38.2%), akathisia (7.2% vs 13.6%), prolactin increase (3.1% vs 14.1%), and weight increase (0.5% vs 5.2%).

CONCLUSION

Lurasidone was found to be non-inferior to risperidone on the primary endpoint with minimal effects on weight, metabolic parameters, or prolactin levels.

Treatment response prediction and individualized identification of first-episode drug-naïve schizophrenia using brain functional connectivity

Identifying biomarkers in schizophrenia during the first episode without the confounding effects of treatment has been challenging. Leveraging these biomarkers to establish diagnosis and make individualized predictions of future treatment responses to antipsychotics would be of great value, but there has been limited progress. In this study, by using machine learning algorithms and the functional connections of the superior temporal cortex, we successfully identified the first-episode drug-naive (FEDN) schizophrenia patients (accuracy 78.6%) and predict their responses to antipsychotic treatment (accuracy 82.5%) at an individual level. The functional connections (FC) were derived using the mutual information and the correlations, between the blood-oxygen-level dependent signals of the superior temporal cortex and other cortical regions acquired with the resting-state functional magnetic resonance imaging. We also found that the mutual information and correlation FC was informative in identifying individual FEDN schizophrenia and prediction of treatment response, respectively. The methods and findings in this paper could provide a critical step toward individualized identification and treatment response prediction in first-episode drug-naive schizophrenia, which could complement other biomarkers in the development of precision medicine approaches for this severe mental disorder.

Clinical Pharmacokinetics of a Lipid-Based Formulation of Risperidone, VAL401: Analysis of a Single Dose in an Open-Label Trial of Late-Stage Cancer Patients

BACKGROUND AND OBJECTIVES

A clinical trial was conducted to measure and analyse the pharmacokinetic parameters of a lipid formulation of risperidone, VAL401. The VAL401 formulation is designed to repurpose risperidone from an antipsychotic to an adenocarcinoma treatment, with the lipid formulation altering the cellular uptake of risperidone, thus enabling anticancer biology to be exhibited in preclinical testing.

METHODS

This first human trial of VAL401 measured the concentrations of risperidone and its primary metabolite, 9-hydroxyrisperidone, in the blood of patients after treatment with a single 2-mg dose of VAL401.

RESULTS

The trial provided information on differences in the pharmacokinetic profile of risperidone in VAL401 that may be caused by the formulation and/or the nature of the cancer patient population. VAL401 provided the following key pharmacokinetic parameters for the risperidone plasma concentration after a single 2-mg dose of VAL401, with results normalised to a dosage of 1 mg for comparison with literature values: Tmax, 2 h; Cmax, 8 ng/ml; half-life, 3.5 h; area under the plasma concentration-time curve from time zero to infinity (AUC0-∞), 58.2 ng h2/mL.

CONCLUSIONS

Further comparisons of the pharmacokinetic parameters of risperidone and 9-hydroxyrisperidone in plasma of patients administered VAL401 and the corresponding parameters obtained from published data for conventionally formulated risperidone provide evidence for altered biological processing of VAL401 as compared to risperidone. The absolute values obtained provide support for future studies of VAL401 as a cancer treatment, as the Cmax demonstrates sufficient exposure to reach the concentrations seen during preclinical anticancer testing, yet the overall exposure to the active moiety supports the use of the safety and tolerability data from conventional risperidone during future clinical trials.

Movement Disorders Associated With Antipsychotic Medication in People With Schizophrenia: An Overview of Cochrane Reviews and Meta-Analysis

Movement disorders associated with antipsychotic medications are relatively common, stigmatising, and potentially disabling. Their prevalence in people with psychosis who are prescribed second-generation antipsychotics (SGAs) is uncertain, as is their level of recognition by clinicinas. We conducted meta-analyses of randomised controlled trials included in the Cochrane Database of Systematic Reviews on schizophrenia and schizophrenia-like psychoses to estimate the prevalence of new-onset dystonia, akathisia, parkinsonism, and tremor with SGAs (amisulpride, asenapine, aripiprazole, clozapine, olanzapine, paliperidone, quetiapine, risperidone, L-sulpiride, and ziprasidone) approved in Canada and the UK, comparing them with haloperidol and chlorpromazine. We used a random effects model because of the heterogeneity between-studies in drug dosage and method of ascertainment of movement disorders. Our systematic search yielded 37 Cochrane systematic reviews (28 for SGAs), which generated 316 informative randomised controlled trials (243 for SGAs). With respect to SGAs, prevalence estimates ranged from 1.4% (quetiapine) to 15.3% (L-sulpiride) for dystonia, 3.3% (paliperidone) to 16.4% (L-sulpiride) for akathisia, 2.4% (asenapine) to 29.3% (L-sulpiride) for parkinsonism, and 0.2% (clozapine) to 28.2% (L-sulpiride) for tremor. Prevalence estimates were not influenced by treatment duration, the use of a flexible or fixed dosing scheme, or whether studies used validated instruments for the screening/rating of movement disorders. Overall, we found high overlap on the prevalence of new-onset movement disorders across different SGAs precribed for established psychoses. Variations in prevalence figures across antipsychotic medications were observed for the different movement disorders. Differences in pharmacological properties, such as for the dopamine D2 R association rate and serotonin 5-HT2A antagonism, could contribute to this variation.

Risperidone ameliorates cognitive deficits, promotes hippocampal proliferation, and enhances Notch signaling in a murine model of schizophrenia

Antipsychotic agents have been reported to promote hippocampal neurogenesis and improve cognitive deficits; yet, the molecular mechanisms underlying these actions remain unclear. In the present study, we used a murine model of schizophrenia induced by 5-day intraperitoneal injection with the non-competitive N-methyl-d-aspartate receptor antagonist MK801 (0.3mg/kg/day) to assess cognitive behavioral deficits, changes in Notch signaling, and cellular proliferation in the hippocampus of adult male C57BL/6 mice after 2-week administration of risperidone (Rip, 0.2mg/kg/day) or vehicle. We then utilized in vivo stereotaxic injections of a lentivirus expressing a short hairpin RNA (shRNA) for Notch1 into the dentate gyrus to examine the role of Notch1 in the observed actions of Rip. We found that Rip ameliorated cognitive deficits and restored cell proliferation in MK801-treated mice in a manner associated with the up-regulation of Notch signaling molecules, including Notch1, Hes1, and Hes5. Moreover, these effects were abolished by pretreatment with Notch1 shRNA. Our results suggest that the ability of Rip to improve cognitive function in schizophrenia is mediated in part by Notch signaling.