A 10-Year Observational Study of the Use, Acceptability and Effectiveness of Long-Acting Paliperidone Palmitate: Implications for Clinical Decision Making.

BACKGROUND: Long-acting injectable antipsychotics (LAIs) have been shown to improve adherence and prevent relapse in the treatment of schizophrenia and psychotic disorders, though longitudinal data on treatment outcomes are limited.

OBJECTIVES: To establish the long-term acceptability and effectiveness of paliperidone palmitate once monthly (PP1M).

METHODS: This independent 10-year mirror image study was carried out in a large urban mental health provider. The study evaluated the retention and hospitalization rates 5 years following initiation of PP1M in a naturalistic patient cohort of all adult patients who were newly initiated on PP1M between 2011 and 2015. Electronic records were used to compare the frequency and length of hospital admissions in the 5 years before and after introduction of PP1M. Switching and discontinuation rates and reasons were also recorded with a separate analysis of patients who continued and discontinued PP1M during the study period.

RESULTS: A total of 167 patients were included in the study (70% with schizophrenia, 30% with other diagnoses). Discontinuation rates were 24%, 15%, 17%, 5% and 8% in years 1-5, respectively; poor tolerability was the most common cause for stopping PP1M. Demographic and clinical factors such as age, sex, diagnosis and care setting did not discriminate between continuers and discontinuers. The group that completed 5 years on PP1M (46%) showed an overall reduction of 72% in the mean number and 68% in the mean length of admissions compared to the 5-year period before initiation, with more than half of the patients requiring no admission at all during this period of time (median = 0). On the contrary, discontinuers demonstrated worse outcomes in overall bed occupancy than continuers. Findings were overall similar across the total cohort and schizophrenia-only group.

CONCLUSIONS: Our study has one of the longest durations of follow up of a naturalistic cohort treated with LAIs confirming sustained improvements for patients who continued treatment for up to 5 years with implicit implications for cost effectiveness. Study findings may facilitate shared decision making in this area, overcoming some of the common barriers for use.