65 A Retrospective Study of Aripiprazole Long-acting Once-Monthly Introduction Patterns in Galicia.

BACKGROUND: Antipsychotic drug treatment is a key component of multiple psychiatric treatment algorithms. Second-generation long-acting injectable antipsychotics (LAIs) have been shown to improve adherence in numerous clinical trials. Patients who can benefit from LAIs therapy can be treated with aripiprazole long acting once-monthly (AOM). However the nature of the introduction patterns of AOM is not well characterized in clinical practice.

METHODS: A retrospective observational study of AOM introduction was conducted on 157 patients aged 18-75 years-old (95 males, 62 females) who were initiated on AOM treatment between January 2017 - December 2017 in two independent Mental Health Units in the autonomous region of Galicia (Spain). An analysis of the different trends in switching strategies and its adaptation to the prescribing information was carried out. Results were compared between different dose treatment plans and a comparison between inpatients and outpatients' outcomes was also undertaken. Additional data regarding off-label use was obtained from the sample.

RESULTS: The sample was composed of 157 patients: 31% diagnosed of Schizophrenia (n=48), 14% Schizoaffective Disorder (n=22), 21% Delusional Disorder (n=33), 17% Bipolar Disorder (n=27), 10% Brief Psychotic Disorder (n=15), 4% Psychotic Disorder Not Specified (n=6), 2% Obsessive-Compulsive Disorder (n=3), 2% Paranoid Personality Disorder (n=3). Regarding the location of the first dose administration: 44% (n=69) were administered in an Acute Psychiatric Inpatient Unit, 44% (n=65) were administered in Mental Health Outpatient Clinics, 11% (n=18) in Psychiatric Day Hospitals and 3% (n=5), in Assertive Community Treatment Programs. 74% (n=116) of patients received an initial dose of 400mg of AOM whereas 26% (n=41) were given 300mg of AOM. The previous antipsychotic was aripiprazole orale (OA) in 61% (n=96) of the cases. The most frequent switch between LAIs was "immediate switch" and in the switch between orale antipsychotics and AOM "tapering and overlap" was found to be the most common pattern. The average dose was 20mg/day in all groups except for patients diagnosed with Delusional Disorder (15mg/day). The average duration of treatment with OA after the first dose was: 32days for patients with Schizophrenia, 23days for Delusional Disorder, 30days for Bipolar Disorder and 19days in Schizoaffective Disorder.

CONCLUSIONS: Our analysis identified two main patterns of drug switching, the most frequent being "tapering and overlap" in oral treatment, followed by "immediate switch" in patients treated with LAIs.Although our patients are unlike many of those enrolled in clinical trials, the present study indicates that the predominant switching strategies conforms with the Safety Data Sheet.