Impact of a pharmacist‐administered long‐acting injectable antipsychotic service in a supermarket‐based community pharmacy on medication adherence

Abstract Introduction Long‐acting injectable antipsychotic (LAIA) medications can improve medication adherence in patients with schizophrenia and bipolar disorder due to their 1‐ to 3‐month administration schedules. Objectives The primary objective of this study was to examine the effect of a pharmacist‐administered LAIA service in a supermarket‐based community pharmacy on medication adherence rates. Methods In this descriptive study, service data from July 1, 2017 through February 28, 2018 were obtained from a national chain pharmacy. The study population included all patients utilizing the pharmacist‐administered LAIA service who received one of the following LAIA medications during the study period: aripiprazole, aripiprazole lauroxil, paliperidone palmitate, and risperidone. Patients under the age of 18 and those who received fewer than two pharmacist administrations of the same medication were excluded. Medication adherence was measured using the proportion of days covered (PDC) with ≥80% being considered adherent. Logistic regression analysis was performed to identify factors that affected PDC. Results A total of 78% (500/641) of patients enrolled in the service were determined to be adherent to their LAIA. Statistically significant differences were found between PDC rates based on medication selection. Using aripiprazole (Abilify Maintena) as a reference, patients on paliperidone palmitate (Invega Sustenna), paliperidone palmitate (Invega Trinza), and risperidone (Risperdal Consta) were 2.1 (95% CI 1.3‐3.3, P < .002), 4.4 (95% CI 1.8‐11.2, P < .002), and 4.3 (95% CI 1.6‐11.8, P < .004) times more likely to have a PDC ≥80%, respectively. Conclusion A majority of patients (78%) enrolled in a community pharmacy‐based service in which pharmacists‐administered LAIA medications were shown to be adherent to their medication. Specific LAIA medications were found to be associated with greater medication adherence. Findings from this study will provide insight into effective means of care delivery for other community‐based specialty pharmacy programs.