Comparison of Paliperidone Palmitate and Risperidone Long-Acting Injection in Schizophrenic Patients: Results From a Multicenter Retrospective Cohort Study in France

Comparative effectiveness of long-acting injectable antipsychotics in patients with schizophrenia in Japan

OBJECTIVE

To compare the effectiveness of different long-acting injectable antipsychotics (LAIs) (aripiprazole, paliperidone, risperidone, and fluphenazine/haloperidol) in patients with schizophrenia in Japan.

METHODS

We conducted a retrospective cohort study using two administrative claims databases. The study population consisted of outpatients with schizophrenia who initiated LAIs between May 1, 2015, and November 30, 2019. We directly compared the risk of psychiatric hospitalization and LAI discontinuation among the LAIs based on hazard ratios (HRs) using Cox proportional hazards regression models.

RESULTS

The numbers of eligible patients who initiated aripiprazole, paliperidone, risperidone, and fluphenazine/haloperidol were 303, 124, 73, and 123, respectively. Regarding psychiatric hospitalization, aripiprazole and paliperidone were associated with significantly lower risk compared to fluphenazine/haloperidol (HR of aripiprazole: 0.47, 95 % CI: 0.28-0.78, HR of paliperidone: 0.50, 95 % CI: 0.28-0.89); HR of risperidone showed the same trend as the aripiprazole and paliperidone. Regarding LAI discontinuation, aripiprazole and paliperidone were associated with significantly lower risk of LAI discontinuation compared to fluphenazine/haloperidol (HR of aripiprazole: 0.53, 95 % CI: 95 % CI: 0.35-0.80, HR of paliperidone: 0.57, 95 % CI: 0.35-0.92). Aripiprazole was also associated with a significantly lower risk compared to risperidone (HR: 0.56, 95 % CI: 0.32-0.98).

CONCLUSION

Our study suggests that aripiprazole and paliperidone are superior to fluphenazine/haloperidol in the risk of psychiatric hospitalization and LAI discontinuation. Aripiprazole is superior to risperidone in the risk of LAI discontinuation.

Rehospitalization Risk of Receptor-Affinity Profile in Antipsychotic Drug Treatment: A Propensity Score Matching Analysis Using a Japanese Employment-Based Health Insurance Database

PURPOSE

The aim of this study was to examine whether there is a difference in the risk of rehospitalization when antipsychotics are classified into two groups treated using drugs with a higher or lower affinity to H1 or α1 receptors than to D2 receptors (histamine H1 receptors, adrenaline α1 receptors [HA] high- and HA low-affinity drug group, respectively) based on affinity to receptors related to sedation using a nationwide insurance claims database in Japan.

PATIENTS AND METHODS

We identified eligible patients by the following two criteria: (i) hospitalization due to schizophrenia (International Classification of Disease [ICD]-10 code: F20 or F25) in psychiatric wards between January 1st, 2005 and August 31st, 2017, and (ii) administration of HA high- or HA low-affinity drugs in the next month after discharge from the earliest hospitalization due to schizophrenia (index month). The primary endpoint was rehospitalization due to schizophrenia. The secondary endpoints were (i) involuntary rehospitalization, (ii) concomitant use of anxiolytics/hypnotics, mood stabilizers, and antiparkinsonian drugs, (iii) all-cause death, and (iv) medication discontinuation. Propensity score (PS) matching analysis was applied, and the hazard ratio (HR) of the event rate in the HA high-affinity drug group relative to the HA low-affinity drug group was calculated using Cox's proportional hazards model.

RESULTS

Two thousand nine hundred and forty patients were identified as eligible patients. Among PS-matched patients (819 in each group), the HR in the HA high-affinity drug group compared with the HA low-affinity drug group was 1.018 (0.822-1.260, P = 0.870). Other outcomes did not differ significantly between the two groups.

CONCLUSION

No significant difference was observed in the rehospitalization risk due to schizophrenia associated with HA high-affinity antipsychotic drugs. Although this study was a retrospective PS-matched cohort study, the possibility of masking of the rehospitalization risk cannot be excluded because more than 80% of the patients were administered an anxiolytic/hypnotic at the time of admission.

Long-term effects of paliperidone palmitate on hospital stay and treatment continuation

There is a growing need for real world data on long-term clinical and health resource utilization outcomes. The main purpose of this study was to establish the effects of 1-monthly Paliperidone Palmitate (PP1M) on treatment continuation and hospital stay in routine clinical practice. This is a naturalistic, 6-year mirror-image study examining retention and hospitalization rates 3 years pre-PP1M and 3 years post-PP1M initiation. One hundred seventy-three patients were included; 120 (70%) had a primary diagnosis of schizophrenia and 53 (30%) other diagnosis. In total, 77% of patients continued PP1M for one year, 66% for two years and 55% for three years. For the patients who continued with PP1M for 3 years (n = 95), the mean number of hospital admissions decreased significantly from 1.44 to 0.53 and the mean number of bed days from 93 to 29 bed days 3 years before and 3 years after PP1M initiation (P < 0.001). The group of patients with schizophrenia who continued for 3 years (n = 79) demonstrated similar outcomes. The introduction of PP1M had a significant impact on long-term clinical outcomes. More than half of patients were still continuing on PP1M at 3 years after initiation and had no admission during 3 years follow-up.

Discontinuation rates during long-term, second-generation antipsychotic long-acting injection treatment: A systematic review

AIM

The aim of this review was to analyze the discontinuation rates during long-term treatment with second-generation antipsychotic long-acting injection (SGA-LAI) in adults with either schizophrenia spectrum or bipolar disorders.

METHODS

A systematic search (PubMed, Scopus, and the Cochrane Library) of studies published in English (1 January 2001-12 October 2018) identified 1214 abstracts, which were analyzed independently by the author and two colleagues. Studies were retrieved and reviewed if they reported primary data on the discontinuation rate before the study end during treatment lasting ≥36 weeks. Data were extracted from 51 articles meeting the inclusion criteria.

RESULTS

In all head-to-head comparisons, and studies on patients with schizophrenia spectrum or bipolar disorders, the discontinuation rate before the study end in patients treated with SGA-LAI was, at best, similar to that recorded in patients treated with first-generation antipsychotics in either oral or LAI formulations or with oral SGA. In particular, in most of the SGA-LAI long-term studies, the rate of premature dropout was higher than 50%.

CONCLUSION

Reviewed data suggest that SGA-LAI show no clear superiority over less expensive drugs (including first-generation antipsychotic LAI and oral antipsychotic formulations) in reducing the risk of premature antipsychotic discontinuation. Thus, alternative strategies should be considered to improve medication persistence and lower discontinuation rates in patients with severe psychiatric disorders. Planning tailored, individualized, and integrated approaches (including frequent clinical evaluations, and behavioral or other flexible techniques adaptable to different settings and patients) may be an effective intervention for improving patient adherence in long-term pharmacological treatment regimens.