A 10-year mirror-image study of effectiveness and cost of long-acting paliperidone palmitate injectable in patients with schizophrenia or schizoaffective disorder

Acute episodes of Schizophrenia and Schizoaffective Disorder often require hospitalizations and/or psychiatry emergency room (PER) visits, with significant economic burden. Long-acting injectables (LAI), such as the once-monthly Palmitate Paliperidone LAI (1MPP) are effective in suppressing symptoms and raise treatment adherence. This study is the first aimed at evaluating long-term efficacy of initiation of 1MPP. This was a mirror-image study with a total 10 year observational length. Sample was divided into five different groups according to time span of observation: 2,4,6,8, and 10 years. Number of participants per group was 162, 129, 95, 77 and 35, respectively. Main outcomes were number and length of hospitalizations and number of PER visit. Significant reductions in these outcomes after initiation of 1MPP were found in all groups. Subgroups consisting only of patients with full adherence were evaluated, and these had better outcomes. A cost evaluation was also performed, which demonstrated decreases every year, for all main outcomes. Sensitivity analysis in the 2-year group showed results in this time-frame are independent of gender, diagnosis, previous LAI or 1MPP initiation setting. Initiation of 1MPP reduces number and length of hospitalizations up to 5 years, decreasing associated costs. This study increases evidence supporting use of 1MPP in patients with Schizophrenia or Schizoaffective disorder.