Background and importance The 3 monthly formulation of paliperidone palmitate (3MPP) was introduced to the Italian market in 2017 for the treatment of schizophrenia in adult patients. 3MPP is a useful treatment option for patients who are adequately treated with the 1 monthly formulation of paliperidone palmitate (PP) but who may benefit from longer dosing intervals.
Aim and objectives To assess the appropriateness of 3MPP prescriptions and the effectiveness of treatment in our centre.
Material and methods This was an observational retrospective study of patients with a 3MPP prescription between January 2018 and July 2020. The variables used to evaluate appropriateness were the number of switches from PP to 3MPP, dosage and administration time. Effectiveness was evaluated by recording treatment interruptions, dose variations and switch back to PP. Data were extracted from an administrative database and collected in Excel.
Results 38 patients were included, 23 men (60.5%), with a mean age of 50±14 years. The dosages of 3MPP were: 175 mg in 5 patients (13.2%), 263 mg in 6 (15.8%), 350 mg in 18 (47.4%) and 525 mg in 9 (23.7%). In 30 patients (78.9%), the 3MPP prescription was appropriate. The number of switches was 35/38 (92.1%): 3 patients received a first prescription of 3MPP without a previous prescription of antipsychotic depot drugs from our centre. An appropriate dosage was selected in 33/35 patients (94.3%): 1 patient switched from PP 100 mg to 3MPP 263 mg and another from PP 150 mg to 3MPP 263 mg. An appropriate administration time was selected in 35/38 patients (92.1%): 1 patient took the drug every 4 months and two patients received only one administration of 3MPP. In total, six patients interrupted treatment (3 in 2019; 3 in 2020). Dose variation of 3MPP during treatment occurred in 2 patients: 1 switched from 3MPP 350 mg to 525 mg and the other from 3MPP 263 mg to 350 mg. Two patients returned to treatment with PP.
Conclusion and relevance Most of the 3MPP prescriptions were appropriate. This treatment has been shown to be effective in this setting where clinical diagnosis and therapeutic choice are not simple and medication adherence is a clinical challenge. The intervention of the pharmacist by auditing prescriptions is important to further increase appropriate treatments in these patients.
Conflict of interest No conflict of interest