Long-term safety and tolerability of aripiprazole lauroxil in patients with schizophrenia

Barriers to long-acting injectable atypical antipsychotic use in Japan: Insights from a comparative psychiatrist survey

AIMS

To investigate the negative attitudes of Japanese psychiatrists toward atypical long-acting injectable (LAI) antipsychotics, which are the current mainstream LAIs in Japan.

METHODS

We surveyed 69 Japanese psychiatrists using a 5-point Likert scale to assess their attitudes toward atypical LAI antipsychotics. Our assessment referenced concerns identified in a study conducted in Japan a decade ago, which found significant differences when compared with a survey of German psychiatrists. We also identified the factors influencing these negative attitudes. Additionally, the results were compared with those of previous Japanese and German studies.

RESULTS

More than 50% of Japanese psychiatrists expressed negative attitudes toward atypical LAI antipsychotics in various areas. These concerns included apprehensions about cost, reluctance to recommend them initially, pain from injections, complexity of switching to LAI, usage in first-episode cases, and sufficient medication adherence with oral drugs. In all three studies, cost and adequate adherence to oral medication were concerns that exceeded the average of the three negative comments. Age and experience in psychiatry influenced the psychiatrists' attitudes toward using these drugs in first-episode cases.

CONCLUSIONS

These findings shed light on the reasons for the underutilization of atypical LAI antipsychotics and suggest opportunities to enhance their appropriate use in clinical settings.

The antipsychotic medications aripiprazole, brexpiprazole and cariprazine are off-target respiratory chain complex I inhibitors

Antipsychotic drugs are the mainstay of treatment for schizophrenia and provide adjunct therapies for other prevalent psychiatric conditions, including bipolar disorder and major depressive disorder. However, they also induce debilitating extrapyramidal syndromes (EPS), such as Parkinsonism, in a significant minority of patients. The majority of antipsychotic drugs function as dopamine receptor antagonists in the brain while the most recent 'third'-generation, such as aripiprazole, act as partial agonists. Despite showing good clinical efficacy, these newer agents are still associated with EPS in ~ 5 to 15% of patients. However, it is not fully understood how these movement disorders develop. Here, we combine clinically-relevant drug concentrations with mutliscale model systems to show that aripiprazole and its primary active metabolite induce mitochondrial toxicity inducing robust declines in cellular ATP and viability. Aripiprazole, brexpiprazole and cariprazine were shown to directly inhibit respiratory complex I through its ubiquinone-binding channel. Importantly, all three drugs induced mitochondrial toxicity in primary embryonic mouse neurons, with greater bioenergetic inhibition in ventral midbrain neurons than forebrain neurons. Finally, chronic feeding with aripiprazole resulted in structural damage to mitochondria in the brain and thoracic muscle of adult Drosophila melanogaster consistent with locomotor dysfunction. Taken together, we show that antipsychotic drugs acting as partial dopamine receptor agonists exhibit off-target mitochondrial liabilities targeting complex I.

Long-term efficacy and safety of once-monthly Risperidone ISM® in the treatment of schizophrenia: Results from a 12-month open-label extension study

OBJECTIVE

To evaluate long-term efficacy, safety and tolerability of Risperidone ISM® in patients with schizophrenia, a multicenter, open-label extension of the PRISMA-3 study was conducted.

METHODS

Eligible placebo (unstable) and Risperidone ISM® (stabilized) rollover patients from a previous 12-week double-blind phase and de novo stable patients received once-monthly intramuscular injections of Risperidone ISM® 75 or 100 mg for 12 months. The long term-efficacy assessment included the Positive and Negative Syndrome Scale (PANSS), Clinical Global Impression-Severity (CGI-S) and Clinical Global Impression-Improvement (CGI-I) scales. Safety evaluation included treatment-emergent adverse events (TEAEs), injection site reactions (ISR), laboratory tests and several safety scales.

RESULTS

Altogether, 215 patients entered the study (55 unstable, 119 stabilized and 41 stable patients). Most patients (74.9%) completed, and discontinuation rates were broadly similar across the study subgroups, mainly due to withdrawal of consent (12.1%). PANSS total and subscales scores decreased from baseline to endpoint in all groups, with the largest decrease for unstable patients. Improvement from baseline to 12 months was also shown for CGI-S and CGI-I scores for both unstable and stabilized patients; the CGI-S and CGI-I scores remained almost unchanged for the stable group. At least one treatment-related TEAE was reported in 39.1% of patients; the most common were headache (12.1%), hyperprolactinemia (9.8%) and asthenia (5.1%). ISR were reported in 8 (0.3%) patients; injection site pain score was low across the 2355 doses assessed.

CONCLUSION

Risperidone ISM® is an effective, safe, and well-tolerated long-term treatment of schizophrenia in adults, regardless of the initial disease severity or whether patients were previously treated with Risperidone ISM® during an acute exacerbation or switched from stable doses of oral risperidone.

An Integrated Pharmacokinetic-Pharmacodynamic-Pharmacoeconomic Modeling Method to Evaluate Treatments for Adults with Schizophrenia

INTRODUCTION

Schizophrenia is a chronic mental disorder that worsens with each relapse. Long-acting injectable (LAI) antipsychotics may prevent the exacerbation of symptoms and occurrence of relapses through improved continuity of care. Different dose regimens are available for the LAIs aripiprazole monohydrate (AM) and aripiprazole lauroxil (AL), but their cost effectiveness is unclear.

OBJECTIVES

The study aim was to compare costs and effects (relapses) of the different aripiprazole LAI dose regimens to inform clinical and US payer decisions.

METHODS

A state-transition model calculated the outcomes of eight LAI dose regimens based on their relapse rates. As effectiveness data from randomized controlled trials were unavailable, relapse rates were modeled using pharmacokinetic and pharmacodynamic evidence. These described blood plasma levels of aripiprazole as a function of AM and AL dose regimens and described the probability of relapse as a function of aripiprazole blood plasma levels. The analysis had a time horizon of 1 year and took the US healthcare payer perspective. The incremental cost per relapse avoided and the probability of cost effectiveness were calculated in deterministic and probabilistic analyses. Scenario analyses explored the model's main assumptions, and results were validated against external data and other cost-effectiveness analyses.

RESULTS

Monthly administration of AM 400 mg consistently yielded the lowest predicted number of relapses across deterministic, probabilistic, and scenario analyses. The costs of treatment and relapses were projected to be the lowest with a monthly administration of AL 441 mg. The incremental cost per relapse avoided with AM 400 mg ranged from AM 400 mg being dominant to $US83,300. From willingness-to-pay thresholds of $US30,000 per relapse avoided, the probability of cost effectiveness was highest for AM 400 mg. The validation showed alignment with external data.

CONCLUSION

The analysis highlighted the robustness of the novel framework based on pharmacokinetic and pharmacodynamic evidence and demonstrated an application in a postmarketing setting.

New Antipsychotic Medications in the Last Decade

PURPOSE OF REVIEW

Over the last ten years, the treatment of psychosis has seen a near explosion of creative development in both novel agents and new delivery modalities. The current review summarizes these developments over the past decade (2011-2020). We performed a systematic review utilizing PubMed and PsychInfo with the aim of identifying all the RCT and related analyses in adults with psychosis (schizophrenia and mania).

RECENT FINDINGS

We identified 11 significant developments: the introduction of new antipsychotics cariprazine, brexpiprazole, lumateperone, and pimavanserin; introduction of new delivery methods: subcutaneous long-acting risperidone, aripiprazole lauroxil, transdermal asenapine, and inhaled loxapine; and the introduction of new approaches such as olanzapine/samidorphan for olanzapine-associated weight gain, examination of the TAAR1 agonist SEP 363,856 as a test of concept, and the combination of Xanomeline/Trospium, an M₁ and M₄ muscarinic receptor agonist in conjunction with a peripheral anticholinergic. Last decade has seen a tremendous development in second-generation antipsychotics which provides unprecedented treatment options for clinicians in treating psychosis.

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.

Long-term effect of aripiprazole lauroxil on health-related quality of life in patients with schizophrenia

BACKGROUND

This post hoc analysis of clinical trial data evaluated long-term, self-reported mental and physical health-related quality of life (HRQoL) scores in schizophrenia patients receiving aripiprazole lauroxil (AL), an atypical long-acting injectable (LAI) antipsychotic approved for the treatment of schizophrenia in adults.

METHODS

The study population included 291 stable schizophrenia outpatients enrolled in 2 consecutive long-term safety studies of AL given every 4 weeks for up to 124 weeks. HRQoL was measured using the SF-36v2® Health Survey (SF-36v2) over the course of the follow-up. The primary outcome was change in SF-36v2 mental component summary (MCS) and physical component summary (PCS) scores from baseline to 124 weeks. To contextualize these scores, descriptive analyses were conducted to compare the scores with available scores for the general population as well as for other populations with chronic medical (ie, hypertension and type 2 diabetes) or psychiatric (ie, depression) conditions.

RESULTS

Results from this post hoc analysis indicated that the mean MCS score for patients continuing AL improved significantly from baseline over 124 weeks (P < .05, all timepoints), while mean PCS score showed little change over 124 weeks. At baseline, patients had lower (worse) MCS scores than the normed general population, but by week 124, patients had MCS scores comparable to those in the general population. This pattern of change was not observed with PCS scores. Comparison of study MCS scores with those associated with other diseases showed that this schizophrenia cohort had lower scores than those with chronic medical conditions but higher scores than those with depression. PCS scores were higher in the study population than published scores for all reference populations at baseline and week 124.

CONCLUSIONS

In this post hoc analysis, outpatients with schizophrenia who continued the LAI antipsychotic AL showed gradual and sustained improvement in self-reported mental HRQoL over several years of follow-up, whereas self-reported physical HRQoL did not change. By the end of follow-up, mental health scores of study patients with schizophrenia were comparable to those of the general population and better than those of patients with depression.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT01626456 [trial registration date: June 15, 2012] and NCT01895452 [trial registration date: July 5, 2013]).

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.

Pharmacokinetics, Safety, and Tolerability of a 2-Month Dose Interval Regimen of the Long-Acting Injectable Antipsychotic Aripiprazole Lauroxil: Results From a 44-Week Phase I Study

BACKGROUND

Aripiprazole lauroxil (AL) is a long-acting injectable antipsychotic approved for treatment of schizophrenia in adults. Approved AL doses and dosing regimens include 441 mg monthly, 662 mg monthly, and 882 mg monthly or every 6 weeks (q6wk), as well as the most recently approved dose, 1064 mg, administered every 2 months.

OBJECTIVE

Pharmacokinetics, safety, and tolerability of an AL regimen with a dose interval of every 2 months (1064 mg) were compared with two other regimens available as monthly and q6wk options.

METHODS

This study evaluated pharmacokinetics of AL given at a higher dosage strength (1064 mg) and at a longer dose interval (every 8 weeks [q8wk]) than previously studied. Patients with schizophrenia or schizoaffective disorder entering this 44-week, phase I, open-label, multicenter study had no recent exposure to aripiprazole and were maintained on other oral antipsychotics throughout the study. Patients were randomized to one of three AL dose regimens for 24 weeks (four 1064-mg injections [q8wk], five 882-mg injections [q6wk], or seven 441-mg injections [q4wk], with the last AL exposure at week 24). Oral aripiprazole was prohibited. Patients were followed for an additional 20 weeks to assess terminal aripiprazole plasma concentrations and ongoing safety. Plasma concentration samples were obtained at regular intervals to provide pharmacokinetic data for the duration of AL exposure and to measure persistence of plasma aripiprazole concentrations after AL discontinuation.

RESULTS

Eligible patients received AL 1064 mg q8wk (n = 35), 882 mg q6wk (n = 34), or 441 mg q4wk (n = 35). Overall, 103/104 (99.0%) patients were taking concomitant non-aripiprazole oral antipsychotic medications during the study. All three AL dose regimens provided continuous exposure to aripiprazole. Mean aripiprazole concentrations from the 1064-mg q8wk regimen were comparable to the 882-mg q6wk regimen and higher than the 441-mg q4wk regimen. Overall incidence by group of any adverse events (AEs) throughout the study was 68.6% (1064 mg q8wk), 50.0% (882 mg q6wk), and 65.7% (441 mg q4wk). The most common AE across regimens was injection-site pain (range 8.6%-11.4%). Serious AEs were reported by eight patients (all but one [increased psychosis in one patient, 441-mg q4wk group] considered unrelated to study drug). Discontinuations due to AEs were reported for 2.9%, 11.8%, and 5.7% of patients receiving the 8-, 6-, and 4-week regimens, respectively. AEs of akathisia, dyskinesia, and dystonia occurred in 2.9%, 8.6%, and 5.7% of patients in the 1064-mg q8wk group, 8.8%, 0%, and 2.9% in the 882-mg q6wk group, and 8.6%, 0%, and 0% in the 441-mg q4wk group, respectively.

CONCLUSIONS

AL 1064 mg q8wk provided continuous exposure to aripiprazole throughout the 8-week dosing interval and had a safety profile consistent with the 4- and 6-week regimens. These findings were used to support FDA approval of the 1064-mg dose administered every 2 months.

REGISTRATION

Clinicaltrials.gov: NCT02320032.

Switching stable patients with schizophrenia from their oral antipsychotics to aripiprazole lauroxil: a post hoc safety analysis of the initial 12-week crossover period

OBJECTIVE

Switching antipsychotic medications is common in patients with schizophrenia who are experiencing persistent symptoms or tolerability issues associated with their current drug regimen. This analysis assessed the safety of switching from an oral antipsychotic to the long-acting injectable antipsychotic aripiprazole lauroxil (AL).

METHODS

This was a post hoc analysis of outpatients with schizophrenia who were prescribed an oral antipsychotic and who enrolled in an international, open-label, long-term (52-week) safety study of AL. The analysis focused on the first 3 injections of AL 882 mg over 12 weeks, divided into the immediate 4-week crossover period between the first and second AL injections (initiation phase) and the subsequent 8 weeks (stabilization phase). Patients were grouped by preswitch oral antipsychotic medication, and safety and clinical symptoms were assessed.

RESULTS

In total, 190 patients had switched from one of the following oral antipsychotic medications: aripiprazole, conventional antipsychotics, risperidone/paliperidone, olanzapine, or quetiapine. The 12-week completion rate was high (92.1%) and similar across the different preswitch oral antipsychotic groups. Overall, adverse event (AE) rates experienced over 12 weeks were modest; no AEs were considered serious. The most common AEs in the initiation phase were injection site pain (5.8%), insomnia (5.8%), and akathisia (3.2%). No apparent relationship was observed between preswitch medication and early-onset AEs. Mean Positive and Negative Syndrome Scale total scores remained stable during this period across preswitch antipsychotic groups.

CONCLUSION

Switching from an oral antipsychotic to AL was feasible in an outpatient setting for patients with schizophrenia, and the 12-week retention rate was favorable.

Pharmacokinetic Evaluation of a 1-Day Treatment Initiation Option for Starting Long-Acting Aripiprazole Lauroxil for Schizophrenia

BACKGROUND

Aripiprazole lauroxil (AL), a long-acting injectable antipsychotic for the treatment of schizophrenia, requires 21 days of oral aripiprazole supplementation upon initiation. We report findings from a phase 1 study investigating a nanocrystalline milled dispersion of AL (ALNCD) as a potential 1-day initiation regimen. The 1-day initiation regimen is designed to enable rapid achievement of plasma aripiprazole concentrations that are comparable with the 21-day oral initiation regimen. Here, a 6-month pharmacokinetic study compared 2 different initiation regimens for starting AL.

METHODS

Patients were randomized 1:1:1:1 to receive 1 of 4 treatments consisting of the 1-day (single ALNCD injection + one 30-mg dose of oral aripiprazole on day 1 only) or the 21-day (15-mg daily dose of oral aripiprazole for 21 days) initiation regimen, each combined with a starting AL dose of either 441 mg or 882 mg.

RESULTS

In total, 133/161 patients completed the study. The pharmacokinetic profile of the 1-day initiation regimen was comparable to the 21-day initiation regimen; both achieved aripiprazole concentrations in the therapeutic range within 4 days and remained in a comparable concentration range during treatment initiation. Common adverse events (≥5.0%) were injection-site pain, headache, increased weight, insomnia, dyspepsia, and anxiety. Nine akathisia events occurred (4 events in 4 patients and 5 events in 2 patients in the 1-day and 21-day initiation regimen groups, respectively).

CONCLUSIONS

The 1-day initiation regimen resulted in plasma aripiprazole concentrations consistent with the 21-day initiation regimen. Therefore, a single dose of ALNCD with a single 30-mg oral dose of aripiprazole provides an alternative initiation regimen for starting AL.