Risperidone long-acting injectable (LAI) and paliperidone LAI were associated with the most discounted quality-adjusted life-years (QALYs) over 5 years (i.e. 3.764 and 3.763, respectively), with paliperidone LAI less costly than risperidone LAI, resulting in an incremental cost-effectiveness ratio (ICER) of €4,770,018 per QALY gained for risperidone LAI compared with paliperidone LAI. Paliperidone LAI dominated aripiprazole LAI, olanzapine LAI and haloperidol LAI, and was associated with an ICER of €2411 per QALY gained compared with olanzapine oral.

In the probabilistic sensitivity analysis, for any threshold, paliperidone LAI was associated with the highest probability of being the optimal strategy in comparison with all other strategies simultaneously in terms of QALYs gained and relapses avoided.

The present analysis suggests that paliperidone LAI is a cost-effective treatment for patients with schizophrenia in France. However, the study also highlights the scarcity of available data, especially on long-term efficacy.