Loxapine delivered as a thermally generated aerosol does not prolong QTc in a thorough QT/QTc study in healthy subjects

First generation antipsychotic-associated serious adverse events in women: a retrospective analysis of a pharmacovigilance database

BACKGROUND

Women have been under-represented in trials of antipsychotic medications.

AIM

Our primary objective was to evaluate five adverse events (AE) associated with first-generation antipsychotics (FGAs) among women relative to men through an analysis of the FDA Adverse Event Reporting System (FAERS).

METHOD

We queried 24.6 million AE reports from 2000 to 2023 involving FGAs. The study cohort consisted of chlorpromazine (n = 3317), fluphenazine (n = 1124), haloperidol (n = 16,709), loxapine (n = 3151), perphenazine (n = 816), thioridazine (n = 665), thiothixene (n = 244), and trifluoperazine (n = 360). Cases of neuroleptic malignant syndrome (NMS), tardive dyskinesia (TD), Torsades de Pointes (TdP), agranulocytosis (AG), and cerebrovascular adverse events (CVAE) were identified. Reporting odds ratios (ROR) and associated 95% confidence intervals (CI) were calculated with logistic regression for each AE among women relative to men.

RESULTS

A total of 2,857 serious AEs were evaluated in the study cohort (NMS = 1810, TD = 434, TdP = 260, AG = 149, CVAE = 204). The ROR for women compared to men was 0.79 (95% CI, 0.71-0.87) for NMS, 0.83 (0.68-1.01) for TD, 1.21 (0.94-1.53) for TdP, 0.71 (0.51-0.98) for AG, and 0.91 (0.68-1.19) for CVAE. A secondary analysis revealed a higher odds in women compared to men of hospitalization associated with reports of TD (ROR = 1.95, 1.29-2.94) and death associated with reports of AG (ROR = 2.46, 1.15-5.24). A subgroup analysis of haloperidol revealed an ROR = 1.67 (1.26-2.21) for women relative to men for TdP.

CONCLUSION

The subgroup analysis of haloperidol AEs revealed a significantly higher reporting odds ratio for TdP. Additionally, the secondary study findings suggest that women were more vulnerable to worse outcomes associated with certain AEs of FGAs.

Predictors for prolonged qt intervals in acute antipsychotic poisoned patients

Background

Acute antipsychotic poisoning is correlated to a high prevalence of qt interval prolongation.

Aim

This study aimed to evaluate early qt interval prolongation predictors in acute antipsychotic-poisoned patients.

Methodology

This prospective cohort study enrolled 70 symptomatic patients with acute antipsychotic poisoning. Sociodemographic data, toxicological, clinical, investigation, and outcomes were collected and analyzed. The estimation of the corrected qt interval (QTc) was performed using Bazett's method. Primary outcome was normal or abnormal length of QTc interval. Secondary outcomes included duration of hospital stay, complete recovery and mortality. The corrected qt interval was analyzed by univariate and multivariate logistic regression analysis.

Results

Patients were divided into groups A (normal QTc interval up to 440 msec; 58.6% of cases) and B (prolonged QTc interval ≥ 440 msec; 41.4% of cases). Patients in group B had significantly high incidences of quetiapine intake, bradycardia, hypotension, hypokalemia, and long duration of hospital stay. By multivariate analysis, quetiapine [Odd's ratio (OR): 39.674; Confidence Interval (C.I:3.426-459.476)], bradycardia [OR: 22.664; C.I (2.534-202.690)], and hypotension [OR: 16.263; (C.I: 2.168-122.009)] were significantly correlated with prolonged QTc interval.

Conclusion

In acute antipsychotic poisoning, quetiapine, bradycardia, and hypotension are early clinical predictors for prolonged QTc interval.

Fifty years of experience with loxapine for the rapid non-coercive tranquilization of acute behavioral disturbances in schizophrenia patients, and beyond

INTRODUCTION

Acute behavioral disturbances in psychosis, including agitation, comprise a heterogeneous group of manifestations varying in intensity and duration they last for. They require rapid, non-coercive treatments ranging from verbal de-escalation to the calming effect of pharmacological agents. The treatment goals are reduction of patient suffering and prevention of disease deterioration. Stabilizing rather than sedating is preferred to ensure improved compliance and a stronger therapeutic alliance. Furthermore, animal pharmacology and clinical studies on agitation reveal the robust calming and anxiolytic properties of loxapine.

AREAS COVERED

This review covers the pharmacological and clinical history of loxapine along with research developments. It emphasizes the advantages of its multiple formulations ranging from injectable forms and tablets to orally inhaled forms to attain rapid and fine-tuned tranquilization.

EXPERT OPINION

Rapid tranquillization is achieved within 2-6 hours using liquid orally-consumed loxapine, and within an hour or less with its IM or orally inhaled forms. Loxapine has been adopted in the management of a wide range of acute disturbances, such as agitation in psychosis. In the context of personalized medicine, key cellular and molecular elements of the schizophrenia phenotype were recently shown to be improved with loxapine.

Recent advances in drug delivery to the central nervous system by inhalation

INTRODUCTION

Drugs need to enter the systemic circulation efficiently before they can cross the blood-brain barrier and reach the central nervous system. Although the respiratory tract is not a common route of administration for delivering drugs to the central nervous system, it has attracted increasing interest in recent years for this purpose.

AREAS COVERED

In this article, we compare pulmonary delivery to three other common routes (parenteral, oral, and intranasal) for delivering drugs to the central nervous system, followed by summarising the devices used to aerosolise neurological drugs. Recent studies delivering drugs for different neurological disorders via inhalation are then discussed to illustrate the strengths of pulmonary delivery.

EXPERT OPINION

Recent studies provide strong evidence and rationale to support inhaling neurological drugs. Since inhalation can achieve improved pharmacokinetics and rapid onset of action for multiple drugs, it is a non-invasive and efficient method to deliver drugs to the central nervous system. Future research should focus on delivering other small and macro-molecules via the lungs for different neurological conditions.

The future of dry powder inhaled therapy: Promising or Discouraging for systemic disorders?

Dry powder inhalation therapy has been shown to be an effective method for treating respiratory diseases like asthma, Chronic Obstructive Pulmonary Diseases and Cystic Fibrosis. It has also been widely accepted and used in clinical practices. Such success has led to great interest in inhaled therapy on treating systemic diseases in the past two decades. The current coronavirus (COVID-19) pandemic also has increased such interest and is triggering more potential applications of dry powder inhalation therapy in vaccines and antivirus drugs. Would the inhaled dry powder therapy on systemic disorders be as encouraging as expected? This paper reviews the marketed and in-development dry powder inhaler (DPI) products on the treatment of systemic diseases, their status in clinical trials, as well as the potential for COVID-19 treatment. The advancements and unmet problems on DPI systems are also summarized. With countless attempts behind and more challenges ahead, it is believed that the dry powder inhaled therapy for the treatment of systemic disorders still holds great potential and promise.

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.

Up-to-date expert opinion on the safety of recently developed antipsychotics

Introduction There are several new and emerging antipsychotic medication strategies recently marketed or under clinical development for the treatment of several mental disorders. There is the need to provide an up-to-date overview on the safety of this new generation of antipsychotic medications, which includes also the third-generation antipsychotics (TGA). Areas covered The authors aimed at providing a synthesis of the most current evidence about the safety profile of the recently developed and/or marketed antipsychotics. Qualitative synthesis followed an electronic search made inquiring of the following databases: MEDLINE, Embase, PsycINFO, and the Cochrane Library from inception until March 2020, combining free terms and MESH headings for the topics of TGA and recently developed and/or marketed antipsychotics as following: ((safety OR adverse events OR side effects) AND ((brexpiprazole OR cariprazine OR inhaled loxapine OR lumateperone (ITI-007) OR lurasidone OR pimavanserin OR roluperidone (MIN-101) OR transdermal patch asenapine)). Expert opinion Overall, newer antipsychotics display a good safety profile, with a well-demonstrated lower metabolic liability compared to second-generation antipsychotics. Furthermore, TGA appear to specifically target negative symptomatology and improving cognitive domains. Abbreviations Aps=Antipsychotic Drugs; AEs = Adverse Effects; EPS = Extrapyramidal Symptoms; NMS = Neuroleptic malignant syndrome; D = Dopamine; K_i = Inhibitory Constant; 5-HT = Serotonin; ECG = Electrocardiogram; H = Histamine; M = Muscarinic; BMI = Body Mass Index.

Clinical Outcomes in Patients Taking Inhaled Loxapine, Haloperidol, or Ziprasidone in the Emergency Department

OBJECTIVES

Our objective was to compare outcomes of discharge disposition, need for additional medications, and restraint use for patients who received inhaled loxapine compared with patients receiving traditional antipsychotic drugs in the emergency department (ED).

METHODS

A retrospective chart review was conducted on all patients who presented to the ED with agitation and received antipsychotic therapy, including loxapine, ziprasidone, or haloperidol from December 1, 2014, through October 31, 2016.

RESULTS

The mean time from physician assignment to medical clearance was 7.9 hours for patients treated with inhaled loxapine versus 10.3 hours for controls (P < 0.01). Those who received inhaled loxapine were given significantly less benzodiazepines as additional rescue medications as compared with other antipsychotic medications (P < 0.01, 35.2% vs 65.1%). Additionally, restraints were utilized less frequently in the loxapine group (P < 0.01, 1.8% vs 19.8%).

CONCLUSIONS

Treating patients with agitation due to psychotic episodes in an ED setting with inhaled loxapine versus haloperidol or ziprasidone was associated with significantly improved treatment outcomes, suggesting that inhaled loxapine may be a more effective and rapid treatment option.

Examining the safety, efficacy, and patient acceptability of inhaled loxapine for the acute treatment of agitation associated with schizophrenia or bipolar I disorder in adults

Agitation is a common and serious symptom of bipolar mania and schizophrenia, and can be defined as excessive motor and verbal activity. If left unrecognized and untreated, agitation can evolve into aggression, resulting in potential patient and staff injury. An ideal treatment for agitation would have a rapid onset, cause calmness without sedation, and be tolerable, efficacious, and non-coercive, while managing the underlying condition. A novel approach for the treatment of agitation is inhaled loxapine. Inhaled loxapine is rapidly absorbed into the systemic circulation through the alveoli, resulting in a near immediate onset of action. The efficacy of inhaled loxapine was established in an extensive clinical development program that included persons with schizophrenia and bipolar mania. Additionally, inhaled loxapine has comparable efficacy to intramuscular ziprasidone, olanzapine, haloperidol, aripiprazole, and lorazepam, with the added benefit of being non-painful and non-traumatizing. Inhaled loxapine carries a bolded black box warning for bronchospasm, and as a result, in the US, requires enrollment in a Risk Evaluation and Mitigation Strategy program, and is contraindicated in those with pulmonary disease. Additionally, the use of inhaled loxapine can be associated with dysgeusia and throat irritation. Inhaled loxapine requires some degree of patient cooperation, and therefore may not be appropriate for all agitated patients.

Oral Agents for the Management of Agitation and Agitated Delirium in Critically Ill Patients

Agitation is one of the most common issues that critically ill patients experience. Medications used to manage agitation are often administered intravenously or intramuscularly in the acutely agitated, critically ill patient. However, a multimodal approach that utilizes multiple routes of administration may be appropriate. This review summarizes the available literature on oral antipsychotics, clonidine, and valproic acid to manage agitation in critically ill patients while also focusing on their pharmacology and appropriate monitoring. Despite inconclusive findings from different studies, antipsychotics, clonidine, and valproic acid may provide benefit for specific patient populations. As more evidence emerges, these agents may start playing a greater role in the management of agitation, which is not amenable to first-line agents. As health care professionals, it is prudent to be familiar with their dosing regimens, common adverse effects, and the monitoring required to maximize patient benefits and minimize harms.

The Role of Inhaled Loxapine in the Treatment of Acute Agitation in Patients with Psychiatric Disorders: A Clinical Review

Loxapine is a first generation antipsychotic, belonging to the dibenzoxazepine class. Recently, loxapine has been reformulated at a lower dose, producing an inhaled powder that can be directly administered to the lungs to treat the agitation associated with psychiatric disorders, such as schizophrenia and bipolar disorder. Thus, the aim of this narrative and clinical mini-review was to evaluate the efficacy and tolerability of inhaled loxapine in the treatment of acute agitation in patients with psychiatric disorders. The efficacy of inhaled loxapine has been evaluated in one Phase II trial on patients with schizophrenia, and in two Phase III trials in patients with schizophrenia and bipolar disorder. Moreover, there are two published case series on patients with borderline personality disorder and dual diagnosis patients. Inhaled loxapine has proven to be effective and generally well tolerated when administered to agitated patients with schizophrenia and bipolar disorder. Two case series have suggested that inhaled loxapine may also be useful to treat agitation in patients with borderline personality disorder and with dual diagnosis, but further studies are needed to clarify this point. However, the administration of inhaled loxapine requires at least some kind of patient collaboration, and is not recommended in the treatment of severe agitation in totally uncooperative patients. Moreover, the drug-related risk of bronchospasm must always be kept in mind when planning to use inhaled loxapine, leading to a careful patient assessment prior to, and after, administration. Also, the higher costs of inhaled loxapine, when compared to oral and intramuscular medications, should be taken into account when selecting it for the treatment of agitation.

Inhaled loxapine for the urgent treatment of acute agitation associated with schizophrenia or bipolar disorder

BACKGROUND

Acute agitation is a serious complication of schizophrenia and bipolar disorder, which may escalate quickly to aggressive behavior. Rapid treatment is therefore important to calm and stabilize the patient, reducing the potential for harm to the patient and others, and allowing further assessment. Current guidelines suggest that where pharmacologic intervention is indicated, medication should preferably be non-invasive, should have a rapid onset and should control aggressive behavior in the short term without compromising the physician-patient relationship in the long term.

OBJECTIVES

This article presents an overview of a new inhaled formulation of the established antipsychotic loxapine, which aims to provide a more rapidly acting agent for the treatment of acute agitation without the disadvantages of intramuscular or intravenous injection.

DISCUSSION

Inhaled loxapine is rapidly absorbed with intravenous-like pharmacokinetics, with a time to maximum plasma concentration of 2 minutes and a plasma half-life of approximately 6 hours. In phase III studies, loxapine reduced agitation within 10 minutes of inhalation; agitation was decreased at all subsequent assessments during a 24-hour evaluation period. Inhaled loxapine was generally well tolerated with no undue sedation. The most common adverse events were dysgeusia, mild sedation, and dizziness. Inhaled loxapine is contraindicated in patients with asthma, COPD or other pulmonary disease associated with bronchospasm.

CONCLUSIONS

Inhaled loxapine rapidly reduces acute agitation in patients with schizophrenia or bipolar disorder and is generally well tolerated. The non-invasive route of delivery respects the patient's autonomy, reducing the perception of coercion or forced medication. Inhaled loxapine is therefore an effective and appropriate option for use in the emergency setting in patients with acute agitation.

A randomized, placebo-controlled repeat-dose thorough QT study of inhaled loxapine in healthy volunteers

OBJECTIVE

This randomized, double-blind, active- and placebo-controlled, crossover, thorough QT study assessed the effect of two inhaled loxapine doses on cardiac repolarization as measured by corrected QT (QTc) interval in healthy subjects (ClinicalTrials.gov NCT01854710).

METHODS

Subjects received two doses of inhaled loxapine (10 mg) 2 hours apart + oral placebo, two doses of inhaled placebo + oral placebo, or two doses of inhaled placebo + oral moxifloxacin (400 mg; positive control), with ≥ 3 days washout between treatments. Two-sided 90% confidence intervals (CIs) were calculated around least-squares mean predose placebo-subtracted individually corrected QT durations (ΔΔQTcIs) at 12 time points throughout 24 hours after dosing. A ΔΔQTcI 95% upper CI exceeding 10 msec was the threshold indicating QTc prolongation (primary endpoint). Secondary endpoints included Fridericia- and Bazettcorrected QT duration and QTcI outliers Pharmacokinetics and adverse events (AEs) were also assessed.

RESULTS

Of 60 subjects enrolled (mean age, 33.8 years; 52% male), 44 completed the study. Post loxapine dosing, no ΔΔQTcI 95% upper CI exceeded 10 msec; the largest was 6.31 msec 5 minutes post dose 2. Methodology was validated by ΔΔQTcI 95% lower CIs exceeding 5 msec at 9 of 12 time points after moxifloxacin dosing. Loxapine plasma concentrations increased rapidly (mean Cmax, 177 ng/mL; median tmax 2 minutes after dose 2, 2.03 hours after dose 1). There were no deaths, serious AEs, or AEs leading to discontinuation, and one severe AE.

CONCLUSIONS

Primary and secondary endpoints indicated two therapeutic doses of inhaled loxapine did not cause threshold QTc prolongation in this study.

Single Doses up to 800 mg of E-52862 Do Not Prolong the QTc Interval--A Retrospective Validation by Pharmacokinetic-Pharmacodynamic Modelling of Electrocardiography Data Utilising the Effects of a Meal on QTc to Demonstrate ECG Assay Sensitivity

Background

E-52862 is a Sigma-1 receptor antagonist (S1RA) currently under investigation as a potential analgesic medicine. We successfully applied a concentration-effect model retrospectively to a four-way crossover Phase I single ascending dose study and utilized the QTc shortening effects of a meal to demonstrate assay sensitivity by establishing the time course effects from baseline in all four periods, independently from any potential drug effects.

Methods

Thirty two healthy male and female subjects were included in four treatment periods to receive single ascending doses of 500 mg, 600 mg or 800 mg of E-52862 or placebo. PK was linear over the dose range investigated and doses up to 600 mg were well tolerated. The baseline electrocardiography (ECG) measurements on Day-1 were time-matched with ECG and pharmacokinetic (PK) samples on Day 1 (dosing day).

Results

In this conventional mean change to time-matched placebo analysis, the largest time-matched difference to placebo QTcI was 1.44 ms (90% CI: -4.04, 6.93 ms) for 500 mg; -0.39 ms (90% CI: -3.91, 3.13 ms) for 600 mg and 1.32 ms (90% CI: -1.89, 4.53 ms) for 800 mg of E-52862, thereby showing the absence of any QTc prolonging effect at the doses tested. In addition concentration-effect models, one based on the placebo corrected change from baseline and one for the change of QTcI from average baseline with time as fixed effect were fitted to the data confirming the results of the time course analysis.

Conclusion

The sensitivity of this study to detect small changes in the QTc interval was confirmed by demonstrating a shortening of QTcF of -8.1 (90% CI: -10.4, -5.9) one hour and -7.2 (90% CI: -9.4, -5.0) three hours after a standardised meal.

Trial Registration

EU Clinical Trials Register EudraCT 2010 020343 13

Multiple dose pharmacokinetics of inhaled loxapine in subjects on chronic, stable antipsychotic regimens

This randomized, double‐blind, placebo‐controlled, parallel‐group study was to determine the pharmacokinetic characteristics, safety, and tolerability of multiple doses of inhaled loxapine aerosol in subjects on a stable, oral, chronic antipsychotic regimen. Loxapine was delivered by means of a unique thermally generated aerosol comprising drug particles of a size designed for deep lung delivery and absorption. Thirty‐two subjects were randomized 1:1:1:1 to receive inhaled loxapine (total doses of 15, 20, or 30 mg) or inhaled placebo administered in 3 divided doses, given 4 hours apart. Following inhalation, the median T_max was 2 minutes, and concentrations declined to about half C_max approximately 5 minutes later across the 3 dose levels. The dose proportionality across data from this study combined with data from the single‐dose study showed a slope (90%CI) of log AUC_inf versus log dose of 0.818 (0.762–0.875) across the 8 doses (n = 60 subjects) studied, indicating reasonable dose proportionality. The most common adverse events were cough (3 of 32, 9%), sedation (3 of 32, 9%), and dysgeusia (2 of 32, 6%). The inhalation of multiple doses of inhaled loxapine were well tolerated in study subjects and provided a safe, well‐tolerated means for rapidly and reliably achieving therapeutic plasma concentrations of loxapine. ClinicalTrials.gov identifier: NCT00555412

Revisiting loxapine: a systematic review

Loxapine is an antipsychotic used in psychiatry for over 40 years with a well-established profile. Loxapine is a dibenzoxazepine tricyclic antipsychotic agent, available for oral, intramuscular and inhalatory administration. In the light of the recent approval by the regulatory agencies of inhaled loxapine for use in the acute treatment of mild-to-moderate agitation in adults affected with schizophrenia or bipolar disorder, this article aims to critically review the available literature on loxapine, irrespective of its formulation. This review examines the efficacy and tolerability of the various formulations of loxapine in the treatment of agitation and aggression in patients affected with schizophrenia, bipolar disorder and other psychiatric conditions. A comprehensive and systematic literature search of PubMed/MEDLINE was conducted, and relevant pharmacodynamic and pharmacokinetic data was included. The findings from the literature were critically reviewed and synthesized. The available data suggests that the antipsychotic efficacy of loxapine is similar to the efficacy of other typical or atypical antipsychotics, with an adverse effects profile comparable to that of the typical antipsychotics at high doses for chronic treatment. As an acute treatment in agitation associated with schizophrenia or bipolar disorder, inhaled loxapine was developed as an innovative and rapid option which appears to be efficacious and tolerable.