Long-Acting Injectable Antipsychotic Initiation in Child and Adolescent Patients with Psychiatric Disorders.

Objectives: There are currently no long-acting injectable antipsychotics (LAIAs) that are approved by the Food and Drug Administration for use in child and adolescent patients, however these agents are used off-label for the treatment of various psychiatric disorders. This study aims to describe the initiation and maintenance dosing strategies of LAIAs in child and adolescent psychiatry inpatients. Methods: This was a single-site retrospective chart review of patients less than 18 years of age initiated on an LAIA during an acute psychiatric hospitalization between October 1, 2015, and October 31, 2022. Patient demographics and hospital encounter information were collected and analyzed using descriptive statistics. Results: Of the 6402 unique pediatric patients discharged from the acute psychiatric hospital within the specified timeframe, 45 (0.7%) were newly initiated on an LAIA. The average age was 15.6 years (range 10-17), with a greater proportion of male (n = 26, 57.8%) and Black or African American (n = 27, 60%) patients. The LAIA agents prescribed included paliperidone palmitate (n = 21, 46.7%), aripiprazole monohydrate (n = 15, 33.3%), aripiprazole lauroxil (n = 7, 15.6%), haloperidol decanoate (n = 1, 2.2%), and risperidone microspheres (n = 1, 2.2%). Primary diagnosis via International Classification of Diseases-10 code at discharge included schizophrenia spectrum and other psychotic disorders (n = 19, 42.2%); bipolar disorder (n = 14, 31.1%); disruptive, impulse control, and conduct disorders (n = 6, 13.3%); autistic disorder (n = 5, 11.1%); and attention-deficit/hyperactivity disorder (n = 1, 2.2%). Seventeen patients (37.8%) received a loading dose regimen and/or a maintenance dose regimen that differed from adult package-insert dosing. The mean length of stay was 23.7 days, and 14 patients (31.1%) were readmitted to the psychiatric hospital within 6 months of discharge. The mean number of days to readmission was 71.9 days. Conclusions: This retrospective study is the first to focus on LAIA initiation and maintenance dosing strategies of multiple agents in both a child and adolescent patient population. Further research is required to evaluate the impact of LAIAs on clinical outcomes in this patient population.