Switching stable patients with schizophrenia from depot and oral antipsychotics to long-acting injectable risperidone: reasons for switching and safety.

OBJECTIVE

An international, non-randomised study evaluated efficacy and safety of risperidone long-acting injectable (RLAI) compared to previous treatment. To investigate generizability of the European data set to the UK subset safety and switching data are reported here.

METHODS

Patients with schizophrenia or other psychotic disorder, symptomatically stable on antipsychotic medication, received intramuscular injections of RLAI 25 mg (to a maximum of 50 mg) every 2 weeks for 6 months.

RESULTS

Of 182 UK patients enrolled, 79% had schizophrenia, 21% other psychotic disorders. Insufficient efficacy (43%), side effects (45%), and non-compliance (25%) were the most common reasons for switching. Sixty-nine per cent of patients completed the trial; 8% discontinued due to adverse events (AEs). Most frequent treatment-emergent AEs were headache (8.2%), relapse (7.7%) and insomnia (7.1%); 8 (4.4%) patients reported injection-related AEs. There were significant improvements in extrapyramidal symptom rating scale total and subscale (particularly Parkinsonism) scores, regardless of previous medication (total cohort, p < or = 0.0001). There was a small but significant increase in body weight at endpoint (1.2 kg, p = 0.0023). One patient suffered a myocardial infarction and died (not treatment-related). There were no substantial differences between the full data set and the UK sub-population

CONCLUSION

Switch to RLAI was well-tolerated in stable patients over 6 months. The European data set is generalizable to the UK patient population.