ABSTRACT
BACKGROUND: The efficacy of the long-acting injectable formulation of the antipsychotic paliperidone (paliperidone palmitate) has been investigated in randomized controlled trials. Due to the nature of study designs, these may not be representative of usual clinical practice. The aim of this study was to assess the clinical effectiveness of the long-acting injectable antipsychotic paliperidone palmitate using treatment continuation at 1 year as an outcome. METHODS: Patients were initiated on paliperidone palmitate prior to December 2014 in a single health board in Wales (UK). Demographic factors that may have influenced outcome, including diagnosis, age at initiation, sex, inpatient or outpatient status on initiation, were analysed to assess whether they influenced patient outcome. For patients completing 1 year of treatment, inpatient stay in the 12 months prior to and following paliperidone palmitate initiation was compared. RESULTS: Data were available for 64 patients; 41 had a diagnosis of schizophrenia and 7 had previously received clozapine. Continuation rates at 6 and 12 months were 69% and 63% respectively. Treatment continuation was not associated with demographic factors. For continuers, mean inpatient stay pre- and post-initiation was 83.2 ± 105.3 and 73.5 ± 103.3 days respectively (p = 0.61). The most common reason for discontinuation was lack of effect (n = 9). CONCLUSIONS: The proportion of patients remaining on treatment was comparable to that reported in other naturalistic studies. Prescribing for indications outside the product licence was relatively common, but did not appear to influence outcome, although the number of patients in each group was small. Treatment continuation at 6 months appeared to be a predictor of longer-term outcome.
ABSTRACT
BACKGROUND: This study examined 5-year outcomes of patients prescribed risperidone long-acting injection (RLAI) or aripiprazole in a clinical setting, using treatment discontinuation as a measure of effectiveness. METHOD: Patients who received RLAI or aripiprazole in the 18 months following their respective UK launches were included. Two-year outcome data were previously reported for these cohorts; this study reported an additional 3 years of follow up for each group. Data were collected from pharmacy records and by retrospective case note review. Patients were classified as continuers or discontinuers at 5 years and reasons for treatment discontinuation noted. RESULTS: The number of patients remaining on treatment at 2 years (and included in this study) was 28/84 and 27/92 for RLAI and aripiprazole respectively. Two patients treated with RLAI and three treated with aripiprazole were lost to follow up. Therefore, 5-year outcome data were available for 50 patients. Fifteen patients from each group were continuers at 5 years. Of these, four receiving RLAI and three receiving aripiprazole were coprescribed other antipsychotics at study endpoint. Reasons for discontinuation of RLAI and aripiprazole respectively were lack of effect (n = 4; n = 4), adverse effects (n = 3; n = 1), noncompliance or patient choice (n = 2; n = 4) and patient death (n = 2; n = 0). CONCLUSION: There was no significant difference between the proportions of patients continuing RLAI or aripiprazole for 5 years. Continuation rates were relatively low (18% and 16% of the original RLAI and aripiprazole cohorts respectively), whilst coprescription of other antipsychotics at endpoint was relatively common. Lack of effectiveness was the most common reason for discontinuation of both compounds. These findings suggested that clinical effectiveness was somewhat disappointing, although the long period of follow up and number of patients previously treated with clozapine in the original cohorts were confounding factors.