"Long-acting" olanzapine in maintenance therapy of schizophrenia: A study with plasma levels

Therapeutic Drug Monitoring of Long-Acting Injectable Antipsychotics as a Predictor of Relapse in Schizophrenia Spectrum Disorders: A 1-Year Pilot Study

BACKGROUND

Long-acting injectable antipsychotics (LAIs) have been shown to reduce acute episodes of schizophrenia spectrum disorders (SSDs). However, breakthrough relapses are frequent, possibly because of underdosing in clinical practice. In this framework, the advantages of therapeutic drug monitoring (TDM) may be overlooked. This study explored the association of low steady-state LAI levels with a higher risk of relapse in SSDs, despite the use of a licensed posology.

METHODS

Forty-eight clinically stable outpatients with SSD underwent LAI-TDM using liquid chromatography-mass spectrometry for routine observational purposes. Baseline anamnestic, pharmacological, and psychometric evaluations compared subjects with "under-range" versus "in-range" LAI serum levels; between-group comparisons for different LAI treatments were also performed. A binary logistic regression explored which baseline factors (age, sex, previous hospitalizations, psychopathology, specific LAI treatment, and underrange serum levels) predicted relapse during the next 12 months.

RESULTS

Baseline comparisons did not show significant between-group differences, except for a higher percentage of underrange values in individuals receiving olanzapine pamoate. A total of 10 patients (20.8%) relapsed during the follow-up; only underrange LAI levels predicted the event (odds ratio 0.03, 95% confidence interval 0.01-0.36; P = 0.005).

CONCLUSIONS

Even if relapse remains as a multifactorial event, LAI-TDM may identify subjects at risk for this negative outcome, thus optimizing antipsychotic maintenance treatment in the context of precision medicine. The finding of underrange LAI plasma levels in real-world practice should prompt adequate monitoring of clinically stable outpatients to identify the early signs of psychopathological deterioration.

Serious Adverse Drug Reactions to Antipsychotics in Minors with Multiple Disabilities: Preventability and Potential Cost Savings by Therapeutic Drug Monitoring

INTRODUCTION

Children and adolescents with multiple disabilities and mental disorders (CAMD) are frequently treated with antipsychotic drugs. However, CAMD are particularly susceptible to serious adverse drug reactions (sADRs). This retrospective study examined the frequency of sADRs to antipsychotics in CAMD. Further, the potential preventability of these sADRs through therapeutic drug monitoring (TDM) and the potential socio-economic benefits of TDM were explored.

METHODS

Routine clinical data of all patients treated at a specialized psychiatric clinic for CAMD between January 2017 and December 2018 were retrospectively examined. Data on the occurrence of sADRs (definition according to the European Medicines Agency), their causality with antipsychotics, as well as their preventability (Schumock criteria) were extracted from patient files. The prolongation of the hospital stay due to sADRs was calculated, and the cost savings were estimated if TDM had been applied. The data were based on a subsample of the KiDSafe project, supported by the Innovation Fund of the Joint Federal Committee, grant number 01NVF16021.

RESULTS

One hundred two CAMD who were administered at least one antipsychotic drug during inpatient treatment were identified. Of these patients, 22 (21.6%) sADRs with a possible causal relationship with the antipsychotic treatment were documented. Eleven sADRs (50%) could potentially have been prevented through TDM. Mitigating sADRs through TDM likely would have prevented prolonged hospital stays and thus conferred considerable savings for health insurance companies.

DISCUSSION

The routine implementation of TDM is urgently recommended for antipsychotic treatment in CAMD to increase drug therapy safety.

The Relation between the Plasma Concentrations of Long-Acting Atypical Antipsychotics and Clinical Effectiveness in Patients Affected by Schizophrenia or Schizoaffective Disorder: A Comprehensive Overview

Atypical antipsychotic depot medications are currently recommended for patients with schizophrenia (SCZ) to prevent relapse and ameliorate the long-term prognosis of these patients. This review critically summarizes the available data about the association between the plasma concentrations of long-acting Second- Generation Antipsychotics (SGAs) and the clinical effectiveness of these compounds in patients affected by SCZ or schizoaffective disorder. Our question is if the measurement of these concentrations can be helpful for clinicians in predicting treatment response and clinical stabilization of patients. Bibliographic research on the main databases was performed, and 13 studies were finally included in this review. Contrasting results were found between plasma concentrations of long-acting injectable (LAI) risperidone and clinical amelioration according to rating scale scores. Data are too scanty to draw conclusions for olanzapine and paliperidone. In contrast, despite small sample sizes, data are quite concordant in showing a relation between long-acting SGA plasma concentrations and D2 receptor occupancy. Despite the preliminary encouraging results, particularly for D2 receptor occupancy, future research with larger samples will have to confirm the clinical usefulness of measuring LAI SGA plasma concentrations to predict the clinical response of patients affected by severe mental conditions such as SCZ.

Current and emerging long-acting antipsychotics for the treatment of schizophrenia

Introduction: In this review, the authors discuss the role of long-acting injectable antipsychotics (LAIs) for schizophrenia, focusing on the effectiveness and new perspectives introduced by such treatment strategy. Despite their promising pharmacokinetic features and their potential advantages in medication adherence, clinical outcomes, and medical costs, LAIs are not habitually presented as an option for patients, especially in the early phase of schizophrenia.Areas covered: This review explores the panorama of available LAIs for the treatment of schizophrenia, first-episode of psychosis, approved indications, medical costs, medication adherence, side effects, effectiveness and differences between first-generation (FGA)-LAIs and second-generation (SGA)-LAIs.Expert Opinion: LAIs differ in terms of specific indications, approved injection sites, needle size, injection volume, injection interval as well as potential drug-drug interactions, and commonly reported adverse reactions. The approved indications have expanded beyond schizophrenia to include bipolar and schizoaffective disorder. SGA-LAIs are often preferred to FGA-LAIs. FGA-LAIs although are less chosen in new patients due to the induction of cognitive and extrapyramidal side effects, even if, on the other hand, many SGA-LAIs are burden by hyperprolactinemia and weight gain. After a review of the available evidence, insight is provided into the potential and current therapeutic opportunities offered by LAI antipsychotic formulations.

Therapeutic Drug Monitoring of Long-Acting Injectable Antipsychotic Drugs

BACKGROUND

The use of therapeutic drug monitoring (TDM) to guide treatment with long-acting injectable (LAI) antipsychotics, which are increasingly prescribed, remains a matter of debate. The aim of this review was to provide a practical framework for the integration of TDM when switching from an oral formulation to the LAI counterpart, and in maintenance treatment.

METHODS

The authors critically reviewed 3 types of data: (1) positron emission tomography data evaluating dopamine (D2/D3) receptor occupancy related to antipsychotic concentrations in serum or plasma; D2/D3 receptors are embraced as target sites in the brain for antipsychotic efficacy and tolerability, (2) pharmacokinetic studies evaluating the switch from oral to LAI antipsychotics, and (3) pharmacokinetic data for LAI formulations. Based on these data, indications for TDM and therapeutic reference ranges were considered for LAI antipsychotics.

RESULTS

Antipsychotic concentrations in blood exhibited interindividual variability not only under oral but also under LAI formulations because these concentrations are affected by demographic characteristics such as age and sex, genetic peculiarities, and clinical variables, including comedications and comorbidities. Reported data combined with positron emission tomography evidence indicated a trend toward lower concentrations under LAI administration than under oral medications. However, the available evidence is insufficient to recommend LAI-specific therapeutic reference ranges.

CONCLUSIONS

Although TDM evidence for newer LAI formulations is limited, this review suggests the use of TDM when switching an antipsychotic from oral to its LAI formulation. The application of TDM practice is more accurate for dose selection than the use of dose equivalents as it accounts more precisely for individual characteristics.

A review of a recently published guidelines' "strong recommendation" for therapeutic drug monitoring of olanzapine, haloperidol, perphenazine, and fluphenazine

Introduction

In addition to clozapine, there is a growing body of evidence that supports therapeutic drug monitoring (TDM) for additional antipsychotics commonly used in the United States.

Methods

The Arbeitsgemeinschaft für Neuropsychopharmakologie und Pharmakopsychiatrie (AGNP) published TDM guidelines for several psychiatric medications. Sources were identified that the authors used to establish therapeutic reference ranges for haloperidol, fluphenazine, perphenazine, and olanzapine-4 antipsychotics commonly used in the United States with a "strong recommendation" for TDM. The sources were then reviewed for content and appropriateness for utilization in establishing the reference ranges.

Results

Olanzapine had 15 citations, haloperidol had 9, perphenazine had 4, and fluphenazine had 2. The studies' methods were reviewed along with the proposed therapeutic reference ranges.

Discussion

Several limitations of the guidelines were identified. Reference ranges were suggested based on studies of patients with various diagnoses; some patients had an acute exacerbation, and others were in a maintenance phase. An additional publication was identified that reviewed similar (and additional) TDM studies; those conclusions were in slight contrast with those of the AGNP guidelines. In the future, guidance should be given to those looking to conduct TDM studies to standardize methods and make meta-analysis of this data more feasible.

[Therapeutic drug monitoring of risperidone and its active metabolite 9-hydroxyrisperidone in the treatment of schizophrenia]

AIM

To conduct a routine therapeutic drug monitoring (TDM) and analyze its results for the optimization of pharmacotherapy.

MATERIAL AND METHODS

Fifty-six inpatients (in total 68 samples) with various forms of schizophrenia were enrolled. High performance liquid chromatography with mass-spectrometric detection was used for quantitative determination of risperidone and 9-hydroxyrisperidone in the serum.

RESULTS

Concentrations of risperidone and 9-hydroxyrisperidone were correlated with drug dose. Total concentrations in the blood at doses from 2 to 8 mg per day were distributed as follows: 44.1% were in the therapeutic, 29.4% in sub-therapeutic (<20 ng/mL) and 26.5% in conditionally toxic range (>60 ng/mL).

CONCLUSIONS

Concentrations of risperidone and 9-hydroxyrisperidone did not follow the normal distribution. The results showed that monitoring of the total concentration of risperidone and its metabolite 9-hydroxyrisperidone was an effective tool for testing and quality control for the purpose of individualization of pharmacotherapy.

Age Impacts Olanzapine Exposure Differently During Use of Oral Versus Long-Acting Injectable Formulations: An Observational Study Including 8,288 Patients

PURPOSE

Olanzapine is a commonly prescribed antipsychotic available as oral and long-acting injectable (LAI) formulations. Data are lacking on the use and safety of olanzapine-LAI in older patients. The aim of this study was to investigate the effect of increasing age on olanzapine exposure during oral versus LAI administration in a real-life setting.

METHODS

This observational study was based on routine therapeutic drug monitoring data collected during 2005-2017. As a measure of exposure, absolute concentrations and concentration/dose ratios of olanzapine were defined as outcome variables. Linear mixed-model analyzes were used to allow for inclusion of multiple samples per patient and adjustment for covariate effects.

RESULTS

Olanzapine concentrations and doses from 8,288 patients (21,378 measurements) were included. The number of patients on oral treatment was 7,893 (42%, 50 years or older), while 395 were using olanzapine-LAI (27%, 50 years or older). In contrast to oral use, where the dose-adjusted concentration of olanzapine increased significantly for patients 50 years or older (P < 0.001), increasing age had no effect on olanzapine concentration following LAI administration (P = 0.550). The effects of smoking habits and gender were equal in oral and olanzapine-LAI users.

CONCLUSION

While the dose-adjusted systemic exposure of olanzapine increases by age after oral administration, these novel findings from a large patient population show that systemic exposure of olanzapine-LAI is unaffected by age, probably due to the lacking influence of age-related changes in gastrointestinal absorption and/or presystemic metabolism. From a pharmacokinetic point of view, it is therefore no reason to restrict the use of olanzapine-LAI in older patients requiring long-term treatment.

Gray matter volumes may predict the clinical response to paliperidone palmitate long-acting in acute psychosis: A pilot longitudinal neuroimaging study

In schizophrenia, paliperidone palmitate (PP) long acting injectable (LAI) has been reported to sustain plasma concentrations and improve clinical symptoms. Moreover, it has also been demonstrated the important role of total gray matter (GM) volumes in predicting the clinical outcome. However, no studies investigating the association between PP-LAI treatment and brain morphometry has been published so far. Therefore, the main aim of our 24 weeks prospective observational exploratory study was to investigate the relation between brain anatomy and clinical outcome in seven patients with acute psychosis treated with PP-LAI. At baseline and every month (from T0 to T6) patients were clinically evaluated with the Brief Psychiatric Rating Scale (BPRS). 3T Magnetic Resonance Imaging at baseline was acquired and total GM and intracranial volumes were extracted to explore their predictive values on BPRS scores. After 24 weeks of treatment with PP-LAI, patients showed statistically significant improvements in BPRS scores. Moreover, subjects with higher total GM volumes had a significantly higher BPRS improvement at 24 weeks compared to patients with lower total GM volumes. Our findings confirm the effectiveness of PP-LAI in treating acute psychosis and suggest that greater GM volumes predict drug response, potentially supporting a favorable prognosis.

Olanzapine pamoate for the treatment of schizophrenia--a safety evaluation

INTRODUCTION

Non-adherence to long-term treatment is a major issue for patients with schizophrenia and is associated with an increased risk of relapse. Long-acting injectable (LAI) antipsychotics can offer a useful option to improve adherence. Due to the type of sustained-release mechanism, olanzapine pamoate (OLAI) can differ in safety as compared with oral olanzapine. Recent safety data concerning olanzapine pamoate required an update of previous systematic reviews.

AREAS COVERED

Safety data were found in US and EU clinical trial registries, and a literature search was undertaken using the databases PubMed and EMBASE to find all relevant published studies. Where appropriate, the number needed to harm and 95% confidence interval for categorical safety outcomes were calculated.

EXPERT OPINION

The safety profile of OLAI was similar to the well-known safety profile of oral olanzapine, except for the risk of occurrence of post-injection delirium/sedation syndrome (PDSS). Olanzapine pamoate can be a choice for schizophrenic patients with a history of response to and acceptable tolerance of oral olanzapine, who have easy access to mental healthcare settings with emergency services for the treatment of PDSS. Long-term, prospective studies assessing the efficacy and safety of OLAI and head-to-head comparisons with other LAI and oral antipsychotics are needed.