Barriers to the use of three-month Paliperidone Palmitate formulation: a study from an Italian real-world setting

Background: Long-acting injectable paliperidone can improve adherence in psychotic patients and reduce relapses and healthcare resource utilization (HRU). This study compares the effectiveness of the three-monthly paliperidone palmitate (PP3M) with the one-monthly formulation (PP1M) and investigates reasons that hinder the use of PP3M in real-world settings. Methods: The authors conducted a three-phase observational study. For subjects recruited from six psychiatric services in Milan, HRU outcomes of PP3M prescription were evaluated through a 12-month mirror-image design (phase 1) and a comparison of HRU of PP1M-only subjects and PP3M subjects during the year prior to PP3M initiation (phase 2). Lastly, they conducted a survey among physicians concerning reasons for not switching to PP3M (phase 3). Results: A total of 119 subjects (61 on PP3M and 58 on PP1M) were included. One year after PP3M initiation, outpatients' visits decreased significantly. Comparing PP3M with PP1M subjects, no significant difference was found in HRU. Perception of patient's unstable clinical condition was the main reason for maintaining PP1M (32.8%), followed by the need for monthly monitoring (19.7%). Conclusion: PP3M initiation was associated with an overall HRU reduction. Subjects switched to PP3M had similar HRU when compared to those who did not, suggesting similar clinical conditions in both groups.