First-generation versus second-generation long-acting injectable antipsychotic drugs and time to relapse

The development of long-acting injectable formulations (LAIs) of second-generation antipsychotic drugs (SGAs) has been suggested as having advantage over first-generation antipsychotic (FGA) LAIs. In this study, we investigated the hypothesis that there was a longer time to relapse in patients with schizophrenia started on SGA LAI versus FGA LAI.

Patients with a diagnosis of schizophrenia or schizoaffective disorder who were started on an SGA LAI while on an inpatient ward were identified through searching of the anonymised historical medical records at the South London and Maudsley NHS Foundation Trust. Patients starting FGA LAIs matched for diagnosis, age and date of hospital admission were identified. Time to readmission, discontinuation of LAI or death were identified. Kaplan-Meier plots were generated for each group, and the difference between groups analysed using log-rank methods.

There were 157 patients identified in each group. There was no difference in time to readmission, medication discontinuation or death in patients on SGA LAI versus FGA LAI.

We found no evidence of advantage in terms of maintaining response in SGA LAI versus FGA LAI. Prescriber choice should be guided by other factors such as side-effect profile, patient acceptability and price.