Racial/Ethnic Differences in the Pharmacokinetics of Antipsychotics: Focusing on East Asians

Discontinuation Rate of Lurasidone and Quetiapine Extended Release in Bipolar Depression

INTRODUCTION

Lurasidone (LUR) was compared with quetiapine extended release (QUE-ER) regarding 1-year discontinuation in patients with bipolar depression (n=317).

METHODS

This is a retrospective cohort study.

RESULTS

Although the time to all-cause discontinuation was estimated using the Kaplan-Meier survival curve with log-rank tests to compare treatment groups, no difference was found (p=0.317). The Cox proportional hazard model revealed that only the presence of adverse events (AEs) is associated with increased treatment discontinuation (p<0.0001). The most common AEs were akathisia for LUR (17.7%) and somnolence for QUE-ER (34.7%). In other Cox models divided by LUR or QUE-ER, the presence of akathisia or somnolence was associated with increased LUR (p=0.0205) or QUE-ER (p<0.0001) discontinuation, respectively.

DISCUSSION

The acceptability of both antipsychotics to bipolar depression in clinical practice may be similar. However, specific AEs for each antipsychotic (LUR: akathisia and QUE-ER: somnolence) were associated with high treatment discontinuation.

Effect of antipsychotics and mood stabilisers on metabolism in bipolar disorder: a network meta-analysis of randomised-controlled trials

Background

Antipsychotics and mood stabilisers are gathering attention for the disturbance of metabolism. This network meta-analysis aims to evaluate and rank the metabolic effects of the commonly used antipsychotics and mood stabilisers in treating bipolar disorder (BD).

Methods

Registries including PubMed, Embase, Cochrane Library, Web of Science, Ovid, and Google Scholar were searched before February 15th, 2024, for randomised controlled trials (RCTs) applying antipsychotics or mood stabilisers for BD treatment. The observed outcomes were twelve metabolic indicators. The data were extracted by two reviewers independently, and confirmed by another four reviewers and a corresponding author. The above six reviewers all participated in data analyses. Data extraction was based on PRISMA guidelines, and quality assessment was conducted according to the Cochrane Handbook. Use a random effects model for data pooling. The PROSPERO registration number is CRD42023466669.

Findings

Together, 5421 records were identified, and 41 publications with 11,678 complete-trial participants were confirmed eligible. After eliminating possible sensitivity, risperidone ranked 1st in elevating fasting serum glucose (SUCRA = 90.7%) and serum insulin (SUCRA = 96.6%). Lurasidone was most likely to elevate HbA1c (SUCRA = 82.1%). Olanzapine ranked 1st in elevating serum TC (SUCRA = 93.3%), TG (SUCRA = 89.6%), and LDL (SUCRA = 94.7%). Lamotrigine ranked 1st in reducing HDL (SUCRA = 82.6%). Amisulpride ranked 1st in elevating body weight (SUCRA = 100.0%). For subgroup analyses, quetiapine is more likely to affect indicators of glucose metabolism among male adult patients with bipolar mania, while long-term lurasidone tended to affect glucose metabolism among female patients with bipolar depression. Among patients under 18, divalproex tended to affect glucose metabolism, with lithium affecting lipid metabolism. In addition, most observed antipsychotics performed higher response and remission rates than placebo, and displayed a similar dropout rate with placebo, while no between-group significance of rate was observed among mood stabilisers.

Interpretation

Our findings suggest that overall, antipsychotics are effective in treating BD, while they are also more likely to disturb metabolism than mood stabilisers. Attention should be paid to individual applicability in clinical practice. The results put forward evidence-based information and clinical inspiration for drug compatibility and further research of the BD mechanism.

Funding

The National Key Research and Development Program of China (2023YFC2506200), and the Research Project of Jinan Microecological Biomedicine Shandong Laboratory (No. JNL-2023001B).

Global perspectives on bipolar disorder treatment: in-depth comparative analysis of international guidelines for medication selection

BACKGROUND

Bipolar disorder, a chronic mental health condition characterised by fluctuations in mood, energy and functionality, affects millions of individuals worldwide. Its management requires a comprehensive approach, and, as such, treatment guidelines have a pivotal role in guiding clinicians to alleviate symptoms, prevent relapse and enhance overall patient well-being. However, the treatment landscape is far from homogenous, with significant variations existing across different countries.

AIMS

This study aimed to explore and compare treatment guidelines for bipolar disorder in various regions, shedding light on the factors that influence therapeutic approaches and thus offering insights that could contribute to the ongoing refinement of evidence-based practices in management.

METHOD

The study explores various international treatment guidelines for bipolar disorder that have been updated after 2014. Guidelines from the UK, Canada, Australia/New Zealand, South Korea and the International College of Neuropsychopharmacology are scrutinised to identify factors contributing to the observed differences among them.

RESULTS

The variations in recommended drugs across guidelines arise from the approaches employed in guideline development - whether relying on expert consensus or meta-analysis results. Timing disparities in conducting these analyses and the selection of studies also exert influence. Moreover, differences in metabolic enzymes among diverse races and the health policies implemented by individual nations play a significant part in shaping these differences.

CONCLUSION

The primary hindrance to consistent treatment conclusions lies in the scarcity of high-quality research results, leading to variations in guidelines. Enhancing evidence-based recommendations necessitates the undertaking of large-scale studies dedicated to assessing treatments for bipolar disorder.

Comparison of brexpiprazole, aripiprazole, and placebo for Japanese major depressive disorder: A systematic review and network meta-analysis

AIM

This systematic review and frequentist network meta-analysis used random-effects models is conducted to determine whether there are differences in the efficacy, acceptability, tolerability, and safety profiles of brexpiprazole (BRE) and aripiprazole (ARI) for Japanese with major depressive disorder (MDD) who were inadequately responsive to antidepressants.

METHODS

Outcome measures were scores on the Montgomery Åsberg Depression Rating Scale (primary), the Clinical Global Impression severity scale, and social functioning scale; the non-response rate; the non-remission rate; all-cause discontinuation; discontinuation due to adverse events (DAE); at least one adverse event (1AE); serious adverse event, akathisia; tremor; weight gain.

RESULTS

A literature search identified three double-blind, randomized, placebo-controlled trials. These comprised one BRE study (with a 1 mg/day [BRE1] and a 2 mg/day [BRE2]) and two ARI studies (with a 3 mg/day arm and a flexible-dose arm[within the dosage range approved in Japan]) (n = 1736). Both BRE and ARI demonstrated better efficacy than the placebo. BRE but not ARI had a higher DAE than the placebo. ARI but not BRE had a higher 1AE than the placebo. BRE and ARI had a higher risk of akathisia and weight gain than the placebo. There were no significant differences between BRE and ARI for any of the outcomes. Although BRE1 had good efficacy, it carried risk of weight gain. Although BRE2 also had efficacy, it carried risks of DAE, akathisia, and weight gain. However, the risk of akathisia in BRE2 was reduced by an initial dose of 0.5 mg/day rather than 1.0 mg/day.

CONCLUSIONS

Overall BRE showed similar utility to ARI and a good risk-benefit balance.

Does dose reduction of afatinib affect treatment outcomes of patients with EGFR-mutant metastatic non-small cell lung cancer in real-world clinical practice?

Background

Afatinib can be started at a dose lower than the recommended starting dose of 40 mg/day for the treatment of epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC), however treatment outcomes in real-world clinical practice remains unclear.

Methods

This retrospective study of patients with NSCLC from 18 major hospitals (public, private or university teaching hospitals) enrolled in Malaysia's National Cardiovascular and Thoracic Surgical Database (NCTSD) assessed the efficacy of lower doses of afatinib on treatment outcomes in a real-world clinical practice. Data on clinical characteristics, afatinib dosing, and treatment outcomes for patients included in NCTSD from 1st January 2015 to 31st December 2020 were analyzed.

Results

Of the 133 patients studied, 94.7% had adenocarcinoma. Majority of the patients (60.9%) had EGFR exon 19 deletion and 23.3% had EGFR exon 21 L858R point mutation. The mean age of patients was 64.1 years and majority (83.5%) had Eastern Cooperative Oncology Group performance status of 2-4 at diagnosis. The most common afatinib starting doses were 40 mg (37.6%), 30 mg (29.3%), and 20 mg (26.3%) once daily (OD), respectively. A quarter of patients had dose reduction (23.3%) due to side effects or cost constraints. Majority of the patients had partial response to afatinib (63.2%) whilst 2.3% had complete response. Interestingly, the objective response rate was significantly higher (72.3%) with afatinib OD doses of less than 40 mg compared to 40 mg (54.0%) (P=0.032). Patients on lower doses of afatinib were two times more likely to achieve an objective response [odds ratio =2.64; 95% confidence interval (CI): 1.20-5.83; P=0.016]. These patients had a numerically but not statistically longer median time to treatment failure (TTF). Median TTF (95% CI) for the overall cohort was 12.4 (10.02-14.78) months. Median overall survival (95% CI) was 21.30 (15.86-26.75) months.

Conclusions

Lower afatinib doses (<40 mg OD) could be equally effective as standard dose in patients with EGFR-mutant advanced NSCLC and may be more suited to Asian patients, minimizing side effects that may occur at higher dosages of afatinib leading to dose interruptions and affecting treatment outcomes.

Tardive dyskinesia in Asia- current clinical practice and the role of neurologists in the care pathway

Tardive dyskinesia (TD) is a movement disorder that can arise as a side effect of treatment with dopamine receptor-blocking agents (DRBAs), including antipsychotic drugs (APDs) used to manage psychotic illnesses. Second-generation APDs (SGAs) are often preferred to first-generation drugs due to their lower propensity to cause TD, however many SGAs-treated patients still develop the condition. Although TD is a global health concern, evidence regarding the occurrence of TD and how it is managed in Asian countries is currently limited. This article reports the results of a systematic review of the published literature on TD focusing on its prevalence, types of patients, knowledge of the condition, causative factors, and usual treatment pathways in clinical practice in Asian countries. Epidemiological data suggest that the prevalence of TD is increasing globally due to an overall rise in APD use, contributing factors being polypharmacy with multiple APDs, the use of higher than necessary doses, and off-label use for non-psychotic indications. Although exact prevalence figures for TD in Asian countries are difficult to define, there is a similar pattern of rising APD use which will result in increasing numbers of TD patients in this region. These issues need to be addressed and strategies developed to minimize TD risk and manage this disabling condition which impacts patients' quality of life and daily functioning. To date, both research into TD has been predominantly psychiatry focused and the perspectives from neurologists regarding the clinical management of this challenging condition are scarce. However, neurologists have an essential role in managing the movement disorders manifestations that characterize TD. Optimum management of TD, therefore, should ideally involve collaboration between psychiatrists and neurologists in joint care pathways, wherever practical. Collaborative pathways are proposed in this article, and the challenges that will need to be addressed in Asian countries to improve the care of people with TD are highlighted, with a focus on the neurologist's viewpoint and the implications for the management of TD globally.

Quetiapine Oral Solution in Alzheimer's Disease: Efficacy and Dosage Insights from a Real-World Retrospective Study

BACKGROUND

Neuropsychiatric symptoms (NPS) are distressing for patients with dementia, often accelerating functional decline and nursing home placement. Medications such as quetiapine are used to alleviate NPS, but their side effects require cautious use. Liquid formulations such as quetiapine oral suspension suit specific populations; however, real-world data on their use in patients with dementia are limited.

OBJECTIVE

The purpose of this retrospective, naturalistic study was to provide preliminary data on the effects of treatment with quetiapine oral suspension on behavioral and psychiatric disturbances in Alzheimer's disease (AD) outpatients in Taiwan.

METHODS

Between January 2022 and June 2023, data were collected from outpatients with a diagnosis of probable AD who received treatment with Qting® (quetiapine oral solution 25 mg/ml). Primary outcome measures were changes in Neuropsychiatric Inventory (NPI) total score and its sub-items from baseline to the endpoint.

RESULTS

We recruited 66 AD patients with a mean age of 72.1±7.6 years, most of whom were female (69.7%). Twenty-three patients had data on neuropsychological test and NPI scores before and after quetiapine treatment. There was no significant change in global cognitive function from baseline to the endpoint. A significant reduction in NPI total score after quetiapine treatment was noted, while the effect on NPI sub-items was limited. The average maintenance dose was 1.5±0.6 ml.

CONCLUSIONS

We demonstrated our clinical experience of the use of quetiapine oral solution in AD patients with NPS. Our results showed that quetiapine oral solution treatment significantly improved these symptoms at a relatively low dose.

Meta-analysis of CYP2C19 and CYP2D6 metabolic activity on antidepressant response from 13 clinical studies using genotype imputation

Cytochrome P450 enzymes including CYP2C19 and CYP2D6 are important for antidepressant metabolism and polymorphisms of these genes have been determined to predict metabolite levels. Nonetheless, more evidence is needed to understand the impact of genetic variations on antidepressant response. In this study, individual clinical and genetic data from 13 studies of European and East Asian ancestry populations were collected. The antidepressant response was clinically assessed as remission and percentage improvement. Imputed genotype was used to translate genetic polymorphisms to metabolic phenotypes (poor, intermediate, normal, and rapid+ultrarapid) of CYP2C19 and CYP2D6. The association of CYP2C19 and CYP2D6 metabolic phenotypes with treatment response was examined using normal metabolizers as the reference. Among 5843 depression patients, a higher remission rate was found in CYP2C19 poor metabolizers compared to normal metabolizers at nominal significance but did not survive after multiple testing correction (OR=1.46, 95% CI [1.03, 2.06], p=0.033, heterogeneity I2=0%, subgroup difference p=0.72). No metabolic phenotype was associated with percentage improvement from baseline. After stratifying by antidepressants primarily metabolized by CYP2C19 and CYP2D6, no association was found between metabolic phenotypes and antidepressant response. Metabolic phenotypes showed differences in frequency, but not effect, between European- and East Asian-ancestry studies. In conclusion, metabolic phenotypes imputed from genetic variants using genotype were not associated with antidepressant response. CYP2C19 poor metabolizers could potentially contribute to antidepressant efficacy with more evidence needed. CYP2D6 structural variants cannot be imputed from genotype data, limiting inference of pharmacogenetic effects. Sequencing and targeted pharmacogenetic testing, alongside information on side effects, antidepressant dosage, depression measures, and diverse ancestry studies, would more fully capture the influence of metabolic phenotypes.