The effects of adding long-acting injectable antipsychotic drugs to clozapine on relapse and hospitalization in patients with treatment-resistant schizophrenia: a mirror-image retrospective study

Clozapine augmentation with long-acting antipsychotic injections: A case series and systematic review

BACKGROUND

Up to 30% of patients with a diagnosis of treatment-resistant psychosis remain symptomatic despite an optimal trial with the gold standard treatment, clozapine. Emerging evidence suggests the clinical utility of long-acting injections (LAI) in such clinical scenarios. In this study, we aimed to describe clozapine augmentation with LAIs in an inner London hospital and explore the literature on the clinical effectiveness of this treatment modality.

METHODS

Patients prescribed clozapine, who were commenced on a LAI between 2007 and 2023 by the United Kingdom's largest mental health trust, were identified from electronic patient records. First, routine clinical data were used to describe the use, effectiveness, and safety of this augmentation strategy. Second, we conducted a literature search up to 1st June 2023 to identify published studies describing clinical outcomes after clozapine augmentation with a LAI. Clinical outcomes were collated and presented in a table, including hospitalisation rates and quantitative clinical assessments using validated scales.

RESULTS

Of the 1248 patients prescribed clozapine in SLaM, three patients (0.2%) received augmentation with the following LAIs: olanzapine embonate, paliperidone palmitate and pipotiazine palmitate. This treatment strategy was clinically effective and generally well tolerated in all three cases. Twelve published studies between 2010 and 2022 were included in the review. Eight distinct LAIs were reported (4 first and 4 second generation antipsychotics), with risperidone and paliperidone most widely studied. All the identified studies were observational including mirror-image studies, case series and case reports. Duration of follow up varied from 3 months to 3 years. There was evidence that the use of LAIs with clozapine can significantly reduce clinical symptoms, hospitalisation rates and bed days. No serious adverse effects were reported.

CONCLUSION

This preliminary evidence suggests clinical utility of LAIs in alleviating residual symptoms and subsequently reducing hospitalisation rates in patients optimised on clozapine treatment. The current study warrants further investigations including a randomised controlled study to establish the clinical efficacy, tolerability, and place in therapy of this treatment modality.

Schizophrenia Patients Discharged on Clozapine Plus Long-Acting Injectable Antipsychotics From a Public Psychiatric Hospital in Taiwan, 2006-2021

BACKGROUND

Some schizophrenia patients treated with clozapine experience an inadequate response and adherence problems. The purpose of this study was to compare time to rehospitalization within 6 months in schizophrenia patients discharged on 3 clozapine regimens. Additionally, the temporal trend of prescription rate in each group was also explored.

METHODS

Schizophrenia patients discharged from the study hospital from January 1, 2006, to December 31, 2021, (n = 3271) were included in the analysis. The type of clozapine prescribed at discharge was divided into 3 groups: clozapine plus long-acting injectable antipsychotics (clozapine + LAIs), clozapine plus other oral antipsychotics (clozapine + OAPs), and clozapine monotherapy. Survival analysis was used to compare time to rehospitalization within 6 months after discharge among the 3 groups. The temporal trend in the prescription rate of each group was analyzed using the Cochran-Armitage Trend test.

RESULTS

Patients discharged on clozapine + LAIs had a significantly longer time to rehospitalization than those on clozapine + OAPs or clozapine monotherapy. The prescription rates of clozapine + LAIs and clozapine + OAPs significantly increased over time, whereas the prescription rates of clozapine monotherapy significantly decreased.

CONCLUSIONS

Compared with the clozapine + OAPs group, the clozapine + LAIs group had a lower risk of rehospitalization and a lower dose of clozapine prescribed. Therefore, if a second antipsychotic is required for patients who are taking clozapine alone, LAIs should be considered earlier.

What Role for Long-Acting Injectable Antipsychotics in Managing Schizophrenia Spectrum Disorders in Children and Adolescents? A Systematic Review

BACKGROUND

Long-acting injectable antipsychotics (LAIAs) are an efficacious and well-tolerated treatment in adults with schizophrenia spectrum disorders (SSD). However, there is less evidence for their use in children and adolescents.

OBJECTIVES

The aim of this systematic review was to summarize findings regarding the effectiveness and side effects of LAIA in children and adolescents with SSD.

METHODS

Four databases (Web of Science, PubMed, MEDES, and Dialnet) were systematically searched for articles published between inception and 12 March, 2022, with the following inclusion criteria: (1) original articles or case reports; (2) providing data on efficacy/effectiveness or safety/tolerability of LAIA treatment in children and adolescents diagnosed with SSD (schizophrenia, schizoaffective disorder, schizophreniform disorder, non-affective psychotic disorder); (3) mean age of samples ≤ 18 years; and (4) written in English or Spanish. Exclusion criteria were review articles, clinical guides, expert consensus as well as posters or oral communication in conferences. The risk of bias was assessed using the ROBIS tool.

RESULTS

From 847 articles found, 13 met the inclusion criteria. These included seven single case reports or case series, four retrospective chart reviews, a 24-week open-label trial, and one observational prospective study, covering a total of 119 adolescents (aged 12-17 years) with SSD. Almost all the articles described data on second-generation LAIA (53 patients on risperidone [once every other week], 33 on paliperidone palmitate [once monthly], 10 on aripiprazole [once monthly], and two on olanzapine pamoate [once monthly]). Twenty-one patients were reported to be only on first-generation LAIAs. Non-adherence was the main reason for starting an LAIA. In all of the studies, the use of LAIAs was associated with improvement in the patients' symptoms.

CONCLUSIONS

There are few studies assessing the use of LAIAs in adolescents with SSD. Overall, these treatments have suggested good effectiveness and acceptable safety and tolerability. However, we found no studies examining their use in children aged < 12 years. The problems and benefits linked to this type of antipsychotic formulation in the child and adolescent population require further study, ideally with prospective, controlled designs.

Patterns of antipsychotic prescription and accelerometer-based physical activity levels in people with schizophrenia spectrum disorders: a multicenter, prospective study

Antipsychotic polypharmacy (APP) in patients with schizophrenia spectrum disorders (SSDs) is usually not recommended, though it is very common in clinical practice. Both APP and SSDs have been linked to worse health outcomes and decreased levels of physical activity, which in turn is an important risk factor for cardiovascular diseases and premature mortality. This real-world, observational study aimed to investigate antipsychotic prescribing patterns and physical activity in residential patients and outpatients with SSDs. A total of 620 patients and 114 healthy controls were recruited in 37 centers across Italy. Each participant underwent a comprehensive sociodemographic and clinical evaluation. Physical activity was monitored for seven consecutive days through accelerometer-based biosensors. High rates of APP were found in all patients, with residential patients receiving more APP than outpatients, probably because of greater psychopathological severity. Physical activity was lower in patients compared to controls. However, patients on APP showed trends of reduced sedentariness and higher levels of light physical activity than those in monopharmacy. Rehabilitation efforts in psychiatric residential treatment facilities were likely to result in improved physical activity performances in residential patients. Our findings may have important public health implications, as they indicate the importance of reducing APP and encouraging physical activity.

Combination With Long-Acting Injectable Antipsychotics and Utilization of Nonstandard Formulations as Compliance Enhancing Methods for Clozapine Users: A Systematic Review and A Case Series

BACKGROUND

Combining clozapine with a long-acting injectable antipsychotic (LAI) or using different, nonstandard formulations of the compound may improve treatment outcomes. We aimed to investigate the utility of the clozapine-LAI combination and different formulations of clozapine for compliance problems of clozapine treatment, and to describe a case series on the combined treatment.

PROCEDURES

We conducted a PubMed search with no date restriction. The number and length of hospitalizations, the results of clinical scales, and adverse events were recorded. We also present a case series of 18 patients using the clozapine-LAI combination. Data were collected from the medical charts and electronic records.

RESULTS

We extracted 9 records describing the use of the clozapine-LAI combination. The case reports and mirror-image studies showed a significant reduction in the number of hospitalizations, length of hospital stays, and number of visits to the emergency department on the combined treatment with no serious adverse events. We included 11 articles for clozapine formulations. The case reports and retrospective data suggested that short-acting intramuscular clozapine was often well tolerated and resulted in an increased acceptance of oral clozapine in the acute phase of illness. In our case series, illness severity and the number of hospitalization per year significantly decreased after the combined treatment, besides a significant improvement in the functioning scores. Hyperprolactinemia and extrapyramidal side effects were reported due to concomitant LAIs.

CONCLUSIONS

Despite the encouraging evidence, the present data are preliminary and mostly based on retrospective studies, and oral-dissolving tablets or oral liquid formulations of clozapine have insufficient evidence for clinical practice. Well-designed, controlled, follow-up studies are needed for both clozapine-LAI combination and different formulations of clozapine.

Third-generation antipsychotics in patients with schizophrenia and non-responsivity or intolerance to clozapine regimen: What is the evidence?

Clozapine is considered « the golden standard » for the management of treatment-resistant schizophrenia, but many patients do not present adequate responsivity even to this antipsychotic. If we add the need to strictly monitor the hematologic and cardiometabolic adverse events during each clozapine trial and the difficulty of preserving therapeutic adherence in patients with low insight, residual negative/positive symptoms, or economic challenges, then the necessity of exploring alternative interventions for these patients becomes obvious. Also, in case of intolerance to clozapine or where clozapine did not induce remission, clinicians have to find new ways to help their patients. Switching to other antipsychotics or using these agents as add-ons to clozapine are the main interventions explored in this review, for patients with schizophrenia resistant to clozapine (ultra-resistant schizophrenia, URS). When clozapine intolerance is detected, conversion to another antipsychotic with distinct pharmacologic properties or formulation (e.g., long-acting intramuscular injectable agents, LAI) may be a useful option. Third-generation antipsychotics (TGA) have been selected for their distinct pharmacodynamically profile, which allows, at a theoretical level, their use in combination with clozapine. This narrative review is based on searching four electronic databases, that retrieved 19 primary and secondary reports on aripiprazole (seven case reports or case series presenting 24 patients; nine clinical trials, and three systematic reviews/meta-analyses), two primary reports on brexpiprazole (case report and case series, N = 3 patients), and six primary reports on cariprazine (case reports and case series, N = 14 patients). Based on the information collected from these reports, which included oral and LAI formulations, the TGA most supported by evidence for the augmentation of clozapine is aripiprazole (high-and medium-quality data), followed by cariprazine (low-quality data). Brexpiprazole has not yet been systematically explored for this indication, and in the case of lumateperone, no report could be found. The efficacy of aripiprazole and cariprazine was supported in the domains of positive, negative, and general symptoms, and aripiprazole may positively impact the metabolic profile in patients with URS. Also, adding TGA may lead to a decrease in the dose of clozapine concomitantly administered. More data derived from good quality research are needed in order to confirm the circumstances of TGAs recommendation in patients with URS, either as monotherapy, or added to clozapine.

Clozapine induces metformin-resistant prediabetes/diabetes that is associated with poor clinical efficacy in patients with early treatment-resistant schizophrenia

BACKGROUND

Two distinct subtypes of treatment-resistant schizophrenia (TRS) have been recently reported, including early-treatment resistance (E-TR) and late-treatment resistance (L-TR). This study was to assess clozapine-induced metformin-resistant prediabetes/diabetes and its correlation with clinical efficacy in schizophrenia E-TR subtype.

METHODS

This prospective cohort study enrolled 230 patients with schizophrenia E-TR subtype and they were treated with adequate doses of clozapine for 16 weeks, during which patients with prediabetes/diabetes were assigned to receive add-on metformin. The main outcomes and measures included incidence of clozapine-induced prediabetes/diabetes and metformin-resistant prediabetes/diabetes, and the efficacy of clozapine as assessed by the Positive and Negative Syndrome Scale (PANSS) score.

RESULTS

Clozapine-induced prediabetes/diabetes occurred in 76.52% of patients (170 prediabetes and 6 diabetes), of which the blood sugar of 43 (24.43%) patients was controlled with metformin. Despite add-on metformin, 47.06% (74/170) of prediabetes patients progressed to diabetes. In total, the incidence of clozapine-induced metformin-resistant prediabetes/diabetes was 75.57% (133/176). On completion of 16-week clozapine treatment, 16.52% (38/230) patients showed clinical improvement with PANSS scores of ≥50% declining. Furthermore, clozapine-induced prediabetes/diabetes was significantly correlated with the poor clinical efficacy of clozapine for schizophrenia E-TR subtype.

CONCLUSIONS

The incidence of clozapine-induced metformin-resistant prediabetes/diabetes was considerably high in the schizophrenia E-TR subtype. Clozapine-induced metformin-resistant prediabetes/diabetes represents an independent risk factor that adversely affects the clinical efficacy of clozapine for the schizophrenia E-TR subtype. This study provided new evidence for re-evaluating the use of clozapine for TRS, especially E-TR subtype, and the use of metformin for the glycemic control of clozapine-induced prediabetes/diabetes.

Clozapine resistant schizophrenia: Newer avenues of management

About 40%-70% of the patients with treatment-resistant schizophrenia have a poor response to adequate treatment with clozapine. The impact of clozapine-resistant schizophrenia (CRS) is even greater than that of treatment resistance in terms of severe and persistent symptoms, relapses and hospitalizations, poorer quality of life, and healthcare costs. Such serious consequences often compel clinicians to try different augmentation strategies to enhance the inadequate clozapine response in CRS. Unfortunately, a large body of evidence has shown that antipsychotics, antidepressants, mood stabilizers, electroconvulsive therapy, and cognitive-behavioural therapy are mostly ineffective in augmenting clozapine response. When beneficial effects of augmentation have been found, they are usually small and of doubtful clinical significance or based on low-quality evidence. Therefore, newer treatment approaches that go beyond the evidence are needed. The options proposed include developing a clinical consensus about the augmentation strategies that are most likely to be effective and using them sequentially in patients with CRS. Secondly, newer approaches such as augmentation with long-acting antipsychotic injections or multi-component psychosocial interventions could be considered. Lastly, perhaps the most effective way to deal with CRS would be to optimize clozapine treatment, which might prevent clozapine resistance from developing. Personalized dosing, adequate treatment durations, management of side effects and non-adherence, collaboration with patients and caregivers, and addressing clinician barriers to clozapine use are the principal ways of ensuring optimal clozapine treatment. At present, these three options could the best way to manage CRS until research provides more firm directions about the effective options for augmenting clozapine response.

[Clozapine in the Treatment of Schizophrenic Psychosis: Patient Characteristics and Antipsychotic Combinations in One Cohort at a Psychiatric Care Hospital]

BACKGROUND

In many studies, clozapine has been reported to have superior effectiveness compared to other antipsychotics. So far there is little systematic data on the practice of clozapine prescription and characteristics of patients treated.

METHOD

Retrospective evaluation of all 392 treatment courses of inpatients with schizophrenic psychoses during one year. Detailed analysis of the patients treated with clozapine including the dosages and additional psychotropic medication.

RESULT

Patients treated with clozapine showed a higher disease severity than patients without clozapine. They received more frequently pharmacological combination therapies, which in some cases significantly contradicted the current guideline recommendations.

CONCLUSION

The results underline the pronounced disease severity of patients receiving clozapine treatment and substantiate evidence from the literature on the limited implementation of guidelines in prescribing practice. The study carried out serves as a pilot survey of a multicenter research project on the practice of prescribing clozapine in psychiatric hospitals in different German regions.

Evidence-Based Expert Consensus Regarding Long-Acting Injectable Antipsychotics for Schizophrenia from the Taiwanese Society of Biological Psychiatry and Neuropsychopharmacology (TSBPN)

OBJECTIVE

Schizophrenia is a chronic, debilitating psychiatric disorder with a high risk of relapse. Nonadherence to medication is a significant contributor to poor outcomes. Although long-acting injectable (LAI) antipsychotics prevent the relapse of schizophrenia, several factors present obstacles to the use of LAI antipsychotics, and clinical guidelines for LAI antipsychotics remain limited. To provide clinical recommendations, the Taiwanese Society of Biological Psychiatry and Neuropsychopharmacology (TSBPN) developed consensus statements for the effectiveness, target populations, initiation timing, and particular clinical situations for the use of LAI antipsychotics in patients with schizophrenia.

METHODS

After a systematic literature review, a working group drafted consensus statements for the selected clinical topics and determined the levels of evidence-based recommendation based on the latest World Federation of Societies of Biological Psychiatry grading system. A scientific committee evaluated the draft statements and decided the final recommendations regarding the grades by anonymous voting after incorporating clinical experience and practice into the evidence from research.

RESULTS

The TSBPN proposed ten consensus statements for the application of LAI antipsychotics. The current evidence supported that LAI antipsychotics could be a treatment option for all schizophrenia patients, including first-episode patients. LAI antipsychotics could be initiated both during an acute psychotic episode and when patients are stable. The consensus also gave recommendations for particular clinical situations with insufficient scientific data, such as for use in elderly or adolescent patients, patients with treatment-resistant schizophrenia, and breakthrough psychosis, and strategies to assist patients/caregivers with decision making.

CONCLUSIONS

The consensus statements developed by the TSBPN provide evidence-based clinical recommendations and could give clinicians more confidence when prescribing LAI antipsychotics to treat schizophrenia, thereby improving treatment outcomes.