Aripiprazole Lauroxil Dosing Regimens: Understanding Dosage Strengths and Injection Intervals.

Aripiprazole lauroxil (AL) is a long-acting atypical antipsychotic approved for the treatment of schizophrenia in adults. AL has five regimen options that offer three different injection intervals using four different dosage strengths. The relationship between dosage strength (milligram injected), injection interval (time between injection visits), and expected steady-state plasma aripiprazole concentrations may not be readily apparent. This article illustrates the relationship by providing visual scenarios of steady-state plasma aripiprazole concentrations for the five AL regimens. The efficacy of AL was originally demonstrated in a pivotal study of two AL regimens (approved as 441 mg monthly and 882 mg monthly). The three additional regimens (662 mg monthly, 882 mg every 6 weeks, and 1064 mg every 2 months) were approved based on pharmacokinetic bridging studies and population pharmacokinetic models. For this paper, expected steady-state concentrations for each AL regimen were derived from the published population pharmacokinetic models and compared using median values and ranges. The five labeled AL regimens differ in dosage strength and injection interval; however, model-simulated concentrations illustrate that each regimen produces steady-state plasma aripiprazole concentrations within the upper and lower bounds associated with known efficacy for AL 441 mg and 882 mg administered monthly. This visual presentation of the relationship between dosage strength of the AL injection, the interval between successive injections, and steady-state aripiprazole plasma concentrations may demonstrate for clinicians how dosage strength and injection interval can be considered in selecting the AL regimen option that best fits the clinical circumstances of the individual patient.

Best Practices for Aripiprazole Lauroxil Administration: From Formulation Development to Injection Technique.

Long-acting injectable (LAI) antipsychotics are an important treatment option for patients with schizophrenia. Advances and variability in formulation technology have provided several LAI antipsychotic treatment options for schizophrenia, with a wide range of doses and dose intervals. However, clinical reviews of LAIs have not focused on formulation development despite its clinical relevance to injection safety and technique. This article reviews the relationship between formulation technology and clinical practices for LAIs, with a focus on aripiprazole lauroxil, a long-acting atypical antipsychotic indicated for the treatment of schizophrenia. The formulation developed for aripiprazole lauroxil is an aqueous-based suspension suitable for use as a prefilled syringe that, after injection, will release aripiprazole slowly into the plasma. The clinical relationship between the aripiprazole lauroxil formulation and proper injection techniques is explained, including why tapping and shaking the syringe to resuspend the drug particles and rapid injection speed are key steps for best injection practices for this formulation.