Experience with risperidone long-acting injection: results of a naturalistic observation study

Abstract

Typical antipsychotics are effective in the management of schizophrenia, but are associated with troublesome adverse effects which may lead to treatment discontinuation and relapse. Long-acting depot formulations of these drugs improve patient compliance, but do not reduce the incidence of adverse effects. There is evidence to suggest that newer atypical antipsychotic drugs have a reduced propensity to induce movement disorders and are associated with a modest reduction in relapse rates. The introduction of risperidone long-acting injection (RLAI) provided clinicians with the first long-acting formulation of an atypical antipsychotic. Objective. The aim of this study was to investigate the outcomes of patients from an acute mental health trust who received RLAI during the 18-month period following its licensing in the UK in order to examine measures of clinical effectiveness, and reasons for treatment discontinuation. Methods. Data were collected retrospectively from medical notes. Results. Fifty-nine patients were included in the study, and at the time of data collection 32 (54%) had discontinued treatment. The most common reason for discontinuation was lack of effectiveness, although all of the patients who discontinued due to lack of response were treatment resistant. RLAI appeared to be well tolerated, with only 12% of patients discontinuing due to adverse effects. Thirty-eight percent of the patients treated with RLAI showed a good response as measured by discharge from inpatient setting, and of the 22 outpatients at time of data collection, five had one re-hospitalisation during the study period. Conclusion. This study concludes that RLAI appears to be well tolerated, and shows some effectiveness in the treatment of schizophrenia, but may not be effective for patients who are treatment resistant.

• Risperidone
• schizophrenia
• long-acting intramuscular injection
• treatment-resistant schizophrenia

Acknowledgements/Statement of interest

This study was conducted by UK National Health Service staff as part of their normal duties. No external funding was received. PND, AT, GMF and WCD have previously received consultancy fees from Janssen-Cilag Ltd, Eli Lilly & Co Ltd and AstraZeneca UK Ltd. The authors wish to thank members of the pharmacy department at Whitchurch hospital for their continued support.