Efficacy and safety profile of paliperidone palmitate injections in the management of patients with schizophrenia: an evidence-based review

Pharmacogenetic intervention improves treatment outcomes in Chinese adult men with schizophrenia

To investigate the clinical application value of pharmacogenetic testing in individualized drug therapy for adult male patients with schizophrenia. A total of 186 adult patients with schizophrenia were enrolled and randomised into the pharmacogenetic (PGx) intervention group and the standard care group. In the PGx intervention group, PGx testing was performed, and the medication regimen was adjusted according to the results of the pharmacogenomic analysis. In contrast, in the standard care group, patients were treated according to the physician's medication experience. Differences in the primary indicator of schizophrenia, the Positive and Negative Symptom Scale (PANSS), and the secondary efficacy measures, the Clinical Global Impressions-Severity of Illness scale (CGI-SI) and Clinical Global Impressions-Global Improvement (CGI-GI) scale, were compared between the intervention and standard care groups. At baseline, the PGx intervention group consisted of 109 individuals, while the standard care group had 77 participants. After 12 weeks of treatment, 49 individuals withdrew from the PGx group (a dropout rate of 45.0%), and 34 withdrew from the standard care group (a dropout rate of 44.2%), with no significant difference in dropout rates between the two groups. The PANSS score reduction rate in the PGx intervention group significantly exceeded that of the standard care group during weeks 3, 6, and 12 of follow-up (P < 0.05). At the 12th week, the PGx intervention group achieved a treatment response rate of 81.7%, significantly surpassing the 48.8% of the standard care group (odds ratio of 4.67, 95% confidence interval of 1.96-11.41; P = 0.001). Furthermore, the PGx intervention was significantly more effective than standard care regardless of whether the patient had a first episode or a relapse (P < 0.05). Furthermore, the Global Assessment of Functioning (GAF) scores and the Personal and Social Performance Scale (PSP) score changes in the PGx intervention group were both significantly different from those in the standard care group (P < 0.05). It is noteworthy that the PGx intervention similarly improves the prognostic outcomes for patients with and without a family history of mental disorders. In conclusion, the application of a PGx intervention treatment model based on PGx testing can significantly improve medication efficacy and shorten the time to achieve the effects of medication in schizophrenia.

Prodrug approaches for the development of a long-acting drug delivery systems

Long-acting formulations are designed to reduce dosing frequency and simplify dosing schedules by providing an extended duration of action. One approach to obtain long-acting formulations is to combine long-acting prodrugs (LA-prodrug) with existing or emerging drug delivery technologies (DDS). The design criteria for long-acting prodrugs are distinct from conventional prodrug strategies that alter absorption, distribution, metabolism, and excretion (ADME) parameters. Our review focuses on long-acting prodrug delivery systems (LA-prodrug DDS), which is a subcategory of long-acting formulations where prodrug design enables DDS formulation to achieve an extended duration of action that is greater than the parent drug. Here, we define LA-prodrugs as the conjugation of an active pharmaceutical ingredient (API) to a promoiety group via a cleavable covalent linker, where both the promoiety and linker are selected to enable formulation and administration from a drug delivery system (DDS) to achieve an extended duration of action. These LA-prodrug DDS results in an extended interval where the API is within a therapeutic range without necessarily altering ADME as is typical of conventional prodrugs. The conversion of the LA-prodrug to the API is dependent on linker cleavage, which can occur before or after release from the DDS. The requirement for linker cleavage provides an additional tool to prolong release from these LA-prodrug DDS. In addition, the physicochemical properties of drugs can be tuned by promoiety selection for a particular DDS. Conjugation with promoieties that are carriers or amenable to assembly into carriers can also provide access to formulations designed for extending duration of action. LA-prodrugs have been applied to a wide variety of drug delivery strategies and are categorized in this review by promoiety size and complexity. Small molecule promoieties (typically MW < 1000 Da) have been used to improve encapsulation or partitioning as well as broaden APIs for use with traditional long-acting formulations such as solid drug dispersions. Macromolecular promoieties (typically MW > 1000 Da) have been applied to hydrogels, nanoparticles, micelles, dendrimers, and polymerized prodrug monomers. The resulting LA-prodrug DDS enable extended duration of action for active pharmaceuticals across a wide range of applications, with target release timescales spanning days to years.

Effectiveness of Paliperidone Palmitate in Reducing Acute Psychiatric Service Use for Patients Suffering from Psychosis-A Retrospective Mirror-Image Study

Poor adherence to antipsychotic treatment is a leading cause of relapse for patients suffering from psychotic disorders and the use of long-acting injectable antipsychotics (LAI) may lead to improved clinical outcomes. This was a 1-year mirror-image study examining the clinical outcomes after monthly administration of paliperidone palmitate (PP1M). The primary outcome measure was the total days of psychiatric hospitalization in the 1-year before and 1-year after initiation of PP1M. Data from 158 patients were included in the study. Most of the patients suffered from schizophrenia. In the year after initiation of PP1M, the mean number of hospitalization days fell from 106.53 to 19.10 (p < 0.001). There were significant reductions in the mean number of hospitalizations and emergency room visits. The use of paliperidone palmitate is associated with significant reduction in both the number of admissions and days of psychiatric hospitalization.

Asian Subgroup Analysis of the REMISSIO Study: A Long-Term Efficacy and Safety Study of Paliperidone Palmitate 3-month Formulation in Patients with Stable Schizophrenia in a Naturalistic Clinical Setting

Objective

Methods

Results

Conclusion

Risk of Drug-induced Movement Disorders with Newer Antipsychotic Agents

Background:

The last decade has seen development of numerous novel antipsychotic drugs with unique mechanisms including long-acting formulations for clinical use. A comparative assessment of these new drugs with each other and previous antipsychotics have not been performed with regards to risk for drug-induced movement disorders (DIMD).

Methods:

Medline was searched from January 2010 to February 2022 for primary research articles and review articles in English using the search terms “extrapyramidal” and “tardive” with individual drug names of novel antipsychotics.

Results:

We identified articles describing the risk of DIMD with 6 novel antipsychotics, 4 novel formulations, and 3 experimental antipsychotics. Both short- and long-term data generally showed comparable to lower risk of DIMD with novel antipsychotics and recent long-acting formulations compared to previously marketed antipsychotics.

Discussion:

Several novel antipsychotics, particularly lumateperone and pimavanserin, show promise in being able to treat psychosis while reducing the risk of DIMD. Long-acting paliperidone may reduce risk of DIMD while other long-acting injectable formulations of SGA have similar risk of DIMD compared to oral formulations. New drug targets for treating psychosis without dopamine blockade also show promise.

Paliperidone Extended Release Versus Olanzapine in Treatment-Resistant Schizophrenia: A Randomized, Double-Blind, Multicenter Study

PURPOSE

Paliperidone is an atypical antipsychotic as effective as other atypical antipsychotics for schizophrenia. However, few studies have explored the efficacy of paliperidone for treatment-resistant schizophrenia. This study aimed to compare the efficacy and safety of paliperidone extended release (ER) versus olanzapine in schizophrenia patients with either poor treatment response or intolerable adverse effects due to standardized antipsychotic therapy.

METHODS

This 12-week randomized, double-blind, multicenter study compared the treatment efficacy on psychotic symptoms, cognitive functions, and tolerance between paliperidone ER (6-15 mg/d, n = 45) and olanzapine (10-30 mg/d, n = 41) in treatment-resistant or treatment-intolerant patients with schizophrenia. The severity of psychotic symptoms was evaluated by the Positive and Negative Syndrome Scale and the Clinical Global Impression Severity of Illness Scale. The cognitive functions were assessed by the MATRICS Consensus Cognitive Battery. In addition, the metabolic impacts were evaluated by weight gain and waist circumference.

RESULTS

Patients with either paliperidone ER or olanzapine treatment showed apparent improvement in psychotic symptoms, without significant intergroup difference. Twelve-week paliperidone ER or olanzapine treatment did not improve the cognitive functions. Both paliperidone ER and olanzapine treatment caused significant increase in weight and waist circumference, and olanzapine had a greater impact on waist circumference than paliperidone ER. In addition, both drugs were well tolerated.

CONCLUSIONS

Paliperidone ER could be a safe alternative for treatment-resistant schizophrenia.

How Loading Dose Strategies for Depot Paliperidone Can Go Wrong

This column presents a real-life case of a patient who developed severe and prolonged Parkinsonism secondary to the loading dose strategy recommended in the prescribing information (package insert) for paliperidone palmitate (Invega Sustenna). This column presents 2 major points. First, the case illustrates what the practitioner must do before following the general guidelines for a loading dose approach to the administration of paliperidone palmitate as outlined in the package insert to decrease the likelihood of a serious and potentially fatal consequence. Second, the case illustrates how therapeutic drug monitoring can be useful in assessing and managing patients who develop an untoward reaction. In this case, therapeutic drug monitoring was done using serum prolactin levels because the available laboratory could not measure the level of the drug itself in plasma, and the case highlights some limitations to keep in mind when using plasma prolactin levels to do such monitoring. To put this case in context, a review of the literature was conducted which identified 3 related cases. The author also refers readers to previous articles on therapeutic drug monitoring and pharmacokinetic considerations that arise when using depot (long-acting injectable) antipsychotics.

The Impact of Long-acting Paliperidone in Reducing Hospitalizations and Clinical Severity in Recent Onset Schizophrenia: A Mirror-image Study in Real-world Clinical Setting

Objective

Schizophrenia is a debilitating disease that disrupts the lives of many affected individuals and exerts a toll on the health system. Only few studies assessed once-monthly injectable formulation of paliperidone palmitate (PP-1M) and other long-acting antipsychotics in recent onset schizophrenia (ROS). To evaluate whether PP-1M is efficacious in reducing frequency and length of hospitalizations and psychosis symptom severity in patients with ROS.

Methods

This mirror-image study included 112 patients, suffering from ROS admitted in a psychiatric ward and successively treated with PP-1M for 1-year. Other psychotic disorders were excluded. We collected socio-demographic data of all subjects included, number and days of hospitalization, as well as Clinical Global Impression-Severity scale (CGI-S) and Clinician-Rated Dimensions of Psychosis Symptom Severity (CRDPSS) scores at the initiation and after 1-year of PP treatment.

Results

After 1-year PP-1M treatment, mean scores of both CGI and CRDPSS significantly decreased (p < 0.001), as well as the mean number of hospitalizations (p = 0.002) and total hospitalization days (p < 0.001) in comparison with those of the previous year.

Conclusion

Our results suggest that PP-1M can be considered as an important therapeutic option in patients with ROS. Its use led to a meaningful reduction in the patient’s use of hospital services, as well as a significant clinical improvement of psychotic symptoms in our sample.

Journey to the Market: The Evolution of Biodegradable Drug Delivery Systems

Biodegradable polymers have been used as carriers in drug delivery systems for more than four decades. Early work used crude natural materials for particle fabrication, whereas more recent work has utilized synthetic polymers. Applications include the macroscale, the microscale, and the nanoscale. Since pioneering work in the 1960’s, an array of products that use biodegradable polymers to encapsulate the desired drug payload have been approved for human use by international regulatory agencies. The commercial success of these products has led to further research in the field aimed at bringing forward new formulation types for improved delivery of various small molecule and biologic drugs. Here, we review recent advances in the development of these materials and we provide insight on their drug delivery application. We also address payload encapsulation and drug release mechanisms from biodegradable formulations and their application in approved therapeutic products.

Relapse and Treatment Adherence in Patients with Schizophrenia Switching from Paliperidone Palmitate Once-Monthly to Three-Monthly Formulation: A Retrospective Health Claims Database Analysis

PURPOSE

Relapse and treatment adherence to paliperidone palmitate once-monthly (PP1M) and three-monthly (PP3M) formulations in patients with schizophrenia were evaluated and compared using health claims data.

PATIENTS AND METHODS

Data (June 2015─June 2018) obtained from the MarketScan® Multi-State Medicaid Database were retrospectively analyzed. Patients aged ≥18 years with ≥1 claim for schizophrenia diagnosis prior to and/or at index date (i.e., date of first PP3M prescription record for PP3M patients and same month/year as the matched PP3M patients for PP1M patients) and continuous enrollment in the insurance plan for ≥12 months prior to index date (baseline) were included. PP1M cohort included patients who received ≥4 PP1M doses. PP3M patients were matched with PP1M patients (1:3) using propensity score matching and prevalent new user design. Outcome measures were relapse rate, time to relapse, proportion of days covered (PDC), and level of treatment adherence defined by PDC in five levels. Time to relapse was compared by Kaplan-Meier survival curves and log-rank test with the hazard ratio calculated using Cox proportion hazards model; PDC by t-test, and relapse rate and PDC categories by chi-square test.

RESULTS

A total of 1564 patients (428 PP3M and 1136 PP1M) were included. Relapse rate was lower in PP3M cohort (10.5%) compared with PP1M cohort (15.7%). Incidence rate of relapse was 8.98/100 person-years (PY) in PP3M cohort and 13.81/100 PY in PP1M cohort. After a mean (SD) follow-up of 456.1 (240.28) days in PP3M cohort and 465.4 (237.95) days in PP1M cohort, PP3M patients had a significantly lower relapse risk (hazard ratio: 0.65, 95% CI: 0.47, 0.90) than PP1M patients. Treatment adherence was significantly (p<0.0001) higher in PP3M versus PP1M cohort.

CONCLUSION

Risk of relapse was significantly lower, and treatment adherence was significantly higher in PP3M cohort compared with PP1M cohort. Higher treatment adherence was associated with lower relapse rate.

Impact of age and gender on paliperidone exposure in patients after administration of long-acting injectable formulations-an observational study using blood samples from 1223 patients

PURPOSE

Paliperidone palmitate is an antipsychotic medication available as long-acting injectable (LAI) formulations. The aim of this study was to investigate the effect of age and gender on paliperidone exposure after administration of LAI formulations.

METHODS

Data on serum concentrations of paliperidone from patients using LAI during were included retrospectively from a therapeutic drug monitoring (TDM) service. Information about dose was obtained from the requisition forms. As a measure of exposure, daily dose-adjusted serum concentration (C/D ratio) was used. Based on initial analysis of C/D ratios versus age, a breaking point close to 50 years was observed, thus deciding the grouping of patients as older (≥50 years) or younger (15-49 years). Linear mixed model analyses, allowing multiple measurements per patients, were used.

RESULTS

In total, 1223 patients were included, whereof 1158 patients used paliperidone LAI in once-monthly intervals. In these patients (27.9% older), older patients had significantly higher paliperidone C/D ratio than younger patients (+20%, p<0.001). Compared to males, females had higher C/D ratio (+14%; p<0.001). Subsequently, older female users of once-monthly LAI intervals had 41% higher paliperidone C/D ratios compared to younger males (15.0 vs. 21.2 nM/mg; p<0.001). Compared to females aged 21-30 years, females with high age (≥70 years) had at least 105% higher paliperidone C/D ratio (p<0.001).

CONCLUSION

The present study shows that older age and female gender are associated with higher paliperidone exposure than younger age and males, respectively. Particularly, older female patients (>50 years) are likely exposed to high concentration and cautious dosing in this subgroup is required.

Second-generation long-acting injections anti-psychotics improve executive functions in patients with schizophrenia: a 12-month real-world study

Background: The main purpose of this study was to assess possible modifications of cognitive performance among schizophrenia patients treated with long-acting injectable antipsychotics (LAIs) of second generation anti-psychotics (SGAs). Our hypothesis is that the shift from the oral formulation to the LAI formulation of SGAs drugs improves the cognitive performance. The secondary objective was to carry out a head to head comparison of two different SGA-LAI treatments [i.e., 1-month Paliperidone Palmitate (PP1M), monthly Aripiprazole (Ari-LAI)] in our study with an independent and real-world setting.Methods: The sample comprised 32 participants who were consecutively recruited over 12 months. Seventeen patients treated with Ari-LAI and 10 treated with PP1M completed psychopathological, neuropsychological and functional assessments. Group differences were explored through chi-squared and t-tests, as appropriate. GLM Repeated Measures were used to study variations of cognitive performance along 12 months and to test differences between drugs.Results: We found an effect of time on the outcomes investigated but this did not depend on the type of LAI used.Conclusions: In comparison with the previous oral treatment with SGAs, patients showed a significant improvement in neurocognitive function after 12 months of treatment with SGA-LAI. Furthermore, there were no differences between the SGA-LAI regimens.Key pointsThe main purpose of this study was to assess possible modification of cognitive performance of patients with Schizophrenia treated with second generation long-acting injectable antipsychotics (SGA-LAIs).The secondary objective was to carry out a head to head comparison of two different SGA-LAIs: Paliperidone Palmitate 1-Month (PP1M) and Aripiprazole Monthly (Ari-LAI).Patients showed a significant improvement in neurocognitive function after 12 months of treatment with SGA-LAI.There were no differences between the SGA-LAI regimens.From a practical point of view, switching to LAI formulation seems to produce further social and cognitive improvements in patients who had already benefitted from oral SGA therapy.

Real-World Analysis of Switching Patients with Schizophrenia from Oral Risperidone or Oral Paliperidone to Once-Monthly Paliperidone Palmitate

PURPOSE

Reducing the dosing frequency of antipsychotics (APs) with long-acting injectables (LAIs) such as once-monthly paliperidone palmitate (PP1M) can improve adherence and clinical outcomes for schizophrenia patients. This US study compared physical and psychiatric comorbidity-related outcomes, AP adherence, healthcare resource utilization (HRU), and costs pre- and post-transition to PP1M among schizophrenia patients treated with oral risperidone/paliperidone pre-PP1M transition.

METHODS

Health insurance claims from the IQVIA™ PharMetrics Plus database (01/01/2012-07/31/2018) were used to identify adults with ≥ 2 schizophrenia diagnoses, ≥ 1 claim for PP1M, and ≥ 30 days of treatment with oral risperidone/paliperidone in the 60 days before the first PP1M claim (i.e., the index date). Comorbidity-related outcomes, adherence to APs (measured via the proportion of days covered [PDC]), all-cause per-patient-per-month (PPPM) HRU, and all-cause PPPM medical, pharmacy, and total costs (i.e., sum of medical and pharmacy costs) during the 6-month periods pre- and post-transition to PP1M were compared using generalized estimating equation models adjusted for repeated measurements. Analyses were replicated in the subset of patients with ≥ 1 all-cause inpatient stay pre-PP1M transition.

FINDINGS

Among 427 schizophrenia patients transitioning from oral risperidone/paliperidone to PP1M, the mean age was 41.1 years and 37.9% were female. Following the PP1M transition, patients were less likely to have claims with a diagnosis for psychoses (odds ratio [OR] 0.41; P < 0.001), hypertension (OR 0.80; P = 0.011), depression (OR 0.70; P < 0.001), drug abuse (OR 0.60; P < 0.001), substance-related and addictive disorders (OR 0.73; P = 0.003), bipolar and related disorders (OR 0.59; P < 0.001), sleep-wake disorders (OR 0.68; P = 0.017), anxiety disorders (OR 0.78; P = 0.034), and other conditions that may require a focus of clinical attention (OR 0.58; P < 0.001). Mean PDC by APs was higher post-PP1M (mean = 0.81) versus pre-PP1M (mean = 0.68) transition. Post-PP1M, patients were less likely to have an all-cause emergency room visit (OR 0.51; P < 0.001) or inpatient stay (OR 0.39; P < 0.001) compared to pre-PP1M. All-cause total healthcare costs remained similar post- versus pre-transition to PP1M (mean monthly cost difference [MMCD] = $228; P = 0.260). Pharmacy costs increased post-PP1M (MMCD = $960; P < 0.001), but were offset by decreasing medical costs (MMCD = - $732; P < 0.001), largely driven by lower costs related to inpatient stays (MMCD = - $695; P < 0.001) and emergency room visits (MMCD = - $63; P < 0.001). For patients with ≥ 1 all-cause inpatient stay pre-PP1M transition (N = 177), a more pronounced improvement in comorbidity-related outcomes, a more pronounced reduction in HRU, and a reduction in total healthcare costs (MMCD = - $1308; P < 0.001) were observed post-transition to PP1M.

IMPLICATIONS

Among schizophrenia patients in the US, transitioning to PP1M following oral risperidone/paliperidone treatment was associated with improved comorbidity-related outcomes, higher adherence, and a reduction in HRU, while remaining cost neutral. Furthermore, patients with ≥ 1 all-cause inpatient stay pre-PP1M transition had significantly lower total healthcare costs post-PP1M transition.

Transdermal Delivery of Antipsychotics: Rationale and Current Status

The aim of this article is to provide the rationale for the development of transdermal formulations of antipsychotics by highlighting their main advantages, starting with an overview of the antipsychotic formulations that are currently available on the market. Progress regarding transdermal antipsychotic formulations was investigated by performing a search of papers, patents and clinical trials published in the last 10 years. Available data on antipsychotic transdermal formulations are reported and discussed, focusing on the characteristics of the dosage forms and their ability to promote drug absorption. Despite the current availability of a large number of antipsychotics, only a few of these drugs (e.g. aripiprazole, asenapine, blonanserin, chlorpromazine, haloperidol, olanzapine, prochlorperazine, quetiapine, and risperidone) have been developed as transdermal delivery systems. Several papers and patents show that transdermal formulations, such as creams, films, gels, nanosystems, patches, solutions, and sprays, have been evaluated with the aim of expanding the clinical utility of antipsychotic drugs. In particular, the employment of different strategies, such as the use of nanoparticles/vesicles, or permeation enhancers as well as microneedles with iontophoresis, may improve the absorption of antipsychotic drugs through the skin. However, few clinical trials on transdermal delivery of antipsychotic drugs are available and only delivery systems containing asenapine and blonanserin have shown interesting clinical results in terms of pharmacokinetic data, efficacy, and tolerability. Recently, the transdermal patch formulation of blonanserin was approved in Japan for the treatment of schizophrenia.