Safety and efficacy of paliperidone palmitate 1-month formulation in Chinese patients with schizophrenia: a 25-week, open-label, multicenter, Phase IV study

Long-Acting Injectable Antipsychotic Treatment for Schizophrenia in Asian Population: A Scoping Review

Evidence of comparative benefits of long-acting injectable (LAI) antipsychotics in Asian patients with schizophrenia has been inconsistent. This scoping review aimed to synthesize the current evidence in the past ten years and provide an overview of efficacy, safety, treatment adherence, patient attitudes, and healthcare resource utilization of LAI in this population. A systematic search was conducted with a pre-defined search strategy in six electronic databases including Chinese National Knowledge Infrastructure (CNKI), Wanfang, PubMed, Embase, CINAHL, and PsycArticles. A total of 46 studies were included, including 15 cohort studies, 13 single-arm trials, 10 randomized controlled trials, four mirror-image studies, three cross-sectional studies, and one controlled clinical trial. Paliperidone palmitate once-monthly injection (27/46) and risperidone LAI (14/46) were the most frequently investigated LAIs. Compared with oral antipsychotic medications (OAMs), LAIs demonstrated a lower rate of relapse/hospitalization and comparable improvement in efficacy. Adverse events (AEs) were similar between LAIs and OAMs, although types and incidence varied. Significant reduction in the length of hospitalization and number of outpatient visits/inpatient admission was observed after initiation of LAIs. These findings suggest that LAI demonstrated comparable efficacy and safety among Asian populations with schizophrenia in comparison to OAMs. Better adherence and lower relapse were observed in patients receiving LAIs from published evidence. Future research is warranted to better understand the comprehensive performance of LAI in specific population or context.

The Effect of Longer Dosing Intervals for Long-Acting Injectable Antipsychotics on Outcomes in Schizophrenia

Medication nonadherence in schizophrenia can have serious implications including relapses and hospitalization. Long-acting injectable (LAI) antipsychotics require fewer administrations, while ensuring sustained medication coverage. In this review, we summarize the expected real-world benefits of longer dosing intervals in the management of schizophrenia. LAIs are associated with improved clinical outcomes of less frequent relapses and reduced functional impairment, encouraging patients to regain control of their lives. Aripiprazole lauroxil and paliperidone palmitate three-monthly (PP3M) LAIs have longer dosing intervals of 2-3 months and provide improved outcomes in patients with schizophrenia. Paliperidone palmitate six-monthly (PP6M) LAI provides the longest dosing interval, twice-yearly dosing, among existing LAIs. Decreasing the frequency of LAI administrations has the potential to reduce occurrence of serious outcomes associated with poor medication adherence. By eliminating the need for daily oral antipsychotic dosing, LAIs could increase the likelihood of patient acceptance, decrease stigma, and promote self-esteem. Longer intervals of medication coverage may be desirable for patients with higher risk of relapse including adults with recent-onset schizophrenia, those living in circumstances that may deprive them of regular access (eg, homeless), those that are in transitions between care settings or to reduce interpersonal contact during public health emergencies (eg, COVID-19 pandemic).

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.

An accidental household outbreak of paliperidone palmitate poisoning via pancake consumption in Lianyungang, China

Introduction

At 11:20 on 26 May 2018, a physician from Lianyungang No. 1 People's Hospital, China, reported that six family members were being treated in the hospital with symptoms from an unknown cause.

Methods

A case series for a food poisoning investigation and an environmental survey were conducted. The patients and their relatives were interviewed in person with a questionnaire contained on a digital tablet, and an investigation of the patients' home was conducted in the presence of police officers. Probable case and confirmed case were defined to serve as a basis for identifying additional cases. Confirmed cases were defined as those probable cases in which blood, stool or vomitus specimens tested positive for paliperidone palmitate and/or its metabolites. A descriptive analysis was performed. Follow-up by telephone was conducted four months later.

Results

There were six probable cases. The median age was 35 years (range: 5-76 years). The attack rate was 100% (n = 6/6) of persons who consumed a family dinner, and the hospitalization rate was also 100% (n = 6/6). The median period between exposure and symptom onset was two hours. The main symptoms included vomiting, nausea, drowsiness, dizziness and severe abdominal pain for adults, and vomiting and severe lethargy for children. An 8-year-old girl further showed changes in the ST segment of her electrocardiogram, and a 5-year-old boy showed QT prolongation. The poisoning substance was suspected to be paliperidone palmitate based on the patients' symptoms and epidemiological findings.

Discussion

We investigated the household food poisoning outbreak through epidemiological analysis and an environmental investigation and determined that it was caused by paliperidone palmitate. The source of the paliperidone palmitate was found to be aluminium containers, taken home by the eldest son who worked at a pharmaceutical company. The containers were sent to a drug disposal centre, and the pharmaceutical company was required to enhance the regulation on the pharmaceutical waste materials to prevent drug poisoning events. By the end of September 2018, the six patients recovered and were released from the hospital, and they did not show any clinical sequelae in four follow-up visits.

Clinical relevance of paliperidone palmitate 3-monthly in treating schizophrenia

Antipsychotics are the mainstay in schizophrenia management, and long-acting injectable (LAI) antipsychotics contribute to the successful maintenance of treatment by improving non-adherence and preventing relapses. Paliperidone palmitate 3-monthly (PP3M) formulation is the only available LAI antipsychotic that offers an extended 3-month window of stable plasma drug concentration, enabling only four injections per year. This paper summarizes clinically relevant endpoints from available evidence for PP3M to bridge translational research gaps and provide measurable outcomes that can be interpreted in clinical practice. Low number-needed-to-treat (NNT) for relapse prevention (NNT [95% CI] 6-month estimate: 4.8 [3.2; 10.0]; 12-month estimate: 3.4 [2.2; 7.0]), and high number-needed-to-harm (NNH [95% CI] akathisia, 27.1 [12.3; -667.1]; tremor, 80.0 [22.5; 67.3]; dyskinesia, -132.6 [44.5; -23.2]; parkinsonism, 160.0 [28.9; -49.8]) quantify the relative benefits and low propensity for adverse events with PP3M. Symptom remission and reductions in positive and negative symptoms indicate treatment stability. Additionally, meaningful functional remission, reduced dosing frequency, and freedom from daily negotiations favorably impact patient preference and attenuate burdensome aspects of caregiving, representing important healthcare determinants that enhance prospects of treatment continuity in schizophrenia. This information can potentially improve clinicians' judgment of treatment choices, clinical response, and patient selection in routine care. Taken together, PP3M is a valuable antipsychotic treatment option, meriting consideration for a broader role in the long-term management of schizophrenia; its utility should not be limited to patients with poor adherence or when oral antipsychotics have failed.

Long-term efficacy and safety of paliperidone palmitate once-monthly in Chinese patients with recent-onset schizophrenia

Background: The subgroup analysis of a primary study (NCT01051531) evaluated the effect of long-term paliperidone palmitate once-monthly (PP1M) therapy in Chinese patients with recent-onset schizophrenia responding unsatisfactorily to previous oral antipsychotics. Patients and methods: This 18-month, open-label study consisted of 3 phases - screening (7 days), treatment (18 months) and end-of-study/withdrawal visit. All enrolled patients (18-50 years) received PP1M: 150 mg eq. (day 1), 100 mg eq. (day 8) followed by a once-monthly flexible dose (50, 75, 100 or 150 mg eq.). Efficacy and safety were assessed. Results: Among the 118 enrolled Chinese patients, 68 completed the treatment (mean age: 25.6 years; male: 54.7%). A clinically meaningful change from baseline to day 548 was observed in Positive and Negative Syndrome scale (primary endpoint, mean [SD]: -15.3 [20.76]), Personal and Social Performance scale (15.9 [19.65]), Clinician Global Impression-schizophrenia score (-1.2 [1.54]) and Medication Satisfaction Questionnaire score (0.9 [1.73]). Commonly reported treatment-emergent adverse events (TEAEs) included insomnia (13.9%), injection-site pain (13.9%), upper respiratory tract infection (13.0%), restlessness (13.0%) and akathisia (13.0%). Serious TEAEs were reported in 9.3% patients with schizophrenia being most common (6.5%) and one death (suicide) was observed. Conclusion: Efficacy of PP1M corroborate findings from earlier studies and no new safety concerns emerged in this Chinese subgroup of patients with schizophrenia.

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

The course of schizophrenia is characterized by multiple relapses, incomplete remission of symptoms, enduring cognitive deficits, and social and occupational functional impairments. Nonadherence to antipsychotic medication is a major determinant of this poor outcome. Long-acting injectable antipsychotics were developed specifically to address the nonadherence problem and are increasingly considered as an early treatment option, in an attempt to prevent accruing morbidity. This review focuses on paliperidone palmitate, the long-acting injectable (LAI) formulation of paliperidone. After considering the pharmacology of paliperidone palmitate, we review the randomized controlled trials, as well as pertinent observational, pragmatic studies for paliperidone once-monthly injections in schizophrenia. Finally, we review the recently introduced 3-monthly formulation of paliperidone palmitate. Taken together, the studies indicate that paliperidone palmitate (PP) has good efficacy compared with placebo and comparable with other antipsychotics including risperidone. The tolerability profile of PP is similar to that of risperidone, with the most important side effects being prolactin elevation, weight gain, and extrapyramidal symptoms. Advantages of PP include the extensive research database and clinical experience with paliperidone and its parent compound risperidone, the availability of different LAI formulations (once-monthly, 3-monthly, and perhaps even longer acting formulations in future), and the novel dose initiation procedure that provides rapid onset of action without the need for oral antipsychotic supplementation.