Aristada 441 mg Every 4 Weeks Oral Aripiprazole Dose Equivalent
Aristada (aripiprazole lauroxil) 441 mg administered every 4 weeks provides mean steady-state aripiprazole plasma concentrations of approximately 125.8 ng/ml, which corresponds to the therapeutic range achieved with oral aripiprazole doses of 10-15 mg daily. 1
Pharmacokinetic Equivalence
The 441 mg monthly (every 4 weeks) dose of Aristada has been directly demonstrated to be efficacious in phase III clinical trials for both acute exacerbations and long-term maintenance therapy of schizophrenia 2
At steady state, Aristada 441 mg every 4 weeks achieves mean aripiprazole concentrations (C avg,ss) of 125.8 ng/ml 1
For context, oral aripiprazole reaches steady-state concentrations within 14 days of dosing, with a recommended target dose range of 10-30 mg/day for schizophrenia 3
The mean elimination half-life of aripiprazole following Aristada administration is approximately 53.9-57.2 days, which is substantially longer than the 75-hour half-life of oral aripiprazole 3, 1
Clinical Dosing Context
The most appropriate oral aripiprazole equivalent for Aristada 441 mg every 4 weeks is 10-15 mg daily, as this represents the standard starting and target dose range that achieves therapeutic efficacy 3
Aristada 441 mg every 4 weeks provides continuous aripiprazole exposure throughout the 4-week dosing interval, maintaining concentrations within the therapeutic range established for oral aripiprazole 4, 1
When initiating Aristada, the standard approach requires 21 days of oral aripiprazole supplementation (typically 10-15 mg daily) to bridge the gap until therapeutic concentrations are achieved from the long-acting injection 5
Important Clinical Considerations
Direct dose conversion between oral and long-acting injectable formulations is not straightforward because the pharmacokinetic profiles differ substantially—oral aripiprazole reaches steady state in 14 days, while Aristada requires approximately 4 weeks to reach full therapeutic effect 3, 1
The 441 mg every 4 weeks regimen was specifically studied and approved based on its ability to maintain aripiprazole concentrations associated with efficacious oral doses of 10-15 mg daily 2
Patients maintained on Aristada 441 mg every 4 weeks who need to transition to oral therapy should receive oral aripiprazole 10-15 mg daily, recognizing that it may take 1-2 weeks (and sometimes up to 4 weeks) for oral aripiprazole to reach its full therapeutic effect 3