Treatment effect with paliperidone palmitate compared with oral antipsychotics in patients with recent-onset versus more chronic schizophrenia and a history of criminal justice system involvement

Abstract

Aim: Long-acting injectable antipsychotics (APs) are not well studied in recent-onset schizophrenia. This exploratory analysis of a study designed to reflect real-world schizophrenia, as defined by patients, interventions and outcomes, compared relative treatment effect between once-monthly paliperidone palmitate (PP) and daily oral APs in patients with recent-onset or chronic illness METHODS: This randomized, open-label, event monitoring board-blinded study compared treatment response in subjects with schizophrenia and a history of criminal justice system involvement following treatment with PP or oral APs for 15 months (ClinicalTrials.gov identifier, NCT01157351). Event-free probabilities were estimated using Kaplan-Meier method; hazard ratios (HRs) were estimated using Cox proportional hazard models. This subgroup analysis analysed data by disease duration (≤5 (recent-onset) or >5 years (chronic illness) since first psychiatric diagnosis).

Results: Seventy-seven subjects met the criteria for recent-onset illness; 365 for chronic illness. HRs (95% CI) for treatment failure for oral APs versus PP were 1.73 (0.87-3.45; P = 0.121) for recent-onset and 1.37 (1.02-1.85; P = 0.039) for chronic illness. Most common adverse events for PP versus oral APs were injection site pain (recent-onset, 26% vs. 0%; chronic, 17% vs. 0%), increased weight (14% vs. 6%; 12% vs. 6%), akathisia (14% vs. 9%; 10% vs. 7%), insomnia (12% vs. 17%; 18% vs. 10%) and anxiety (12% vs. 6%; 10% vs. 8%).

Conclusions: Although neither pre-planned nor adequately powered, the estimated HRs suggest that the relative advantage of PP over oral APs for reducing the risk for treatment failure may be greater in patients with recent-onset schizophrenia than in those with more chronic illness.

Keywords: disease duration; long-acting injectable; oral antipsychotic; paliperidone palmitate; schizophrenia.

Figure 1

Study flow of subjects with recent‐onset or chronic illness in the PRIDE study. *Two subjects did not have data available for the duration of their illness and were not included.

Figure 2

Kaplan–Meier estimate of time to first treatment failure for subjects with (a) recent‐onset (≤5 years) and (b) chronic illness (>5 years). AP, antipsychotic; CI, confidence interval; HR, hazard ratio; PP, paliperidone palmitate.

Figure 3

Kaplan–Meier estimate of time to first psychiatric hospitalization or arrest/incarceration for subjects with (a) recent‐onset (≤5 years) and (b) chronic illness (>5 years). AP, antipsychotic; CI, confidence interval; HR, hazard ratio; PP, paliperidone palmitate.