What is the recommended initiation protocol for Abilify (aripiprazole) injection?

Initiating Abilify Long-Acting Injectable (Aripiprazole LAI)

For patients starting aripiprazole long-acting injectable (AOM 400), use the two-injection start regimen: administer two separate 400 mg intramuscular injections on the same day along with a single 20 mg oral aripiprazole dose, eliminating the need for 14 days of oral supplementation. 1, 2, 3

Two-Injection Start (TIS) Protocol

Administration Details

• Give two 400 mg intramuscular injections of aripiprazole LAI on the same day (typically one in each gluteal muscle) 4, 1, 2
• Administer a single 20 mg oral aripiprazole tablet on the same day as the injections 4, 1, 2
• Schedule the next injection 4 weeks later at 400 mg monthly 4, 2

Advantages Over Traditional One-Injection Start

• The TIS regimen maintains serum levels within the therapeutic window without the peaks above therapeutic range seen with the traditional 14-day oral supplementation, potentially reducing toxicity risk 1
• Eliminates the need for 14 consecutive days of oral aripiprazole, which improves adherence during the critical initiation period and is particularly valuable for patients with poor insight or those urgently transitioning to outpatient care 4, 2, 3
• European HCPs report high satisfaction (84.0%) with patient outcomes using TIS, with 79.8% finding it easy to administer 3

Safety and Tolerability Profile

Expected Adverse Effects

• Monitor for akathisia (restlessness) and extrapyramidal symptoms, which are the most common dose-dependent adverse effects 5, 6
• Adverse effects with TIS are mild to moderate, with no clinically evident difference from the traditional one-injection start regimen 2
• No severe adverse events have been reported with the two-injection start in real-world studies 2

Metabolic Advantages

• Aripiprazole LAI is weight-neutral and lacks metabolic side effects, conferring an advantage over other second-generation antipsychotic LAIs 6

Pre-Administration Considerations

Drug Interactions

• Review all concomitant medications for CYP2D6 and CYP3A4 metabolic inducers and inhibitors before initiating 6
• Strong CYP3A4 inducers may reduce aripiprazole levels and compromise efficacy 6

Patient Selection

• Common appropriate indications include poor adherence (85.1% of prescribers), relapse history (59.6%), and high hospitalization rates (48.9%) 3
• The regimen is particularly valuable for patients with poor insight who are at risk of non-adherence upon discharge 4

Common Pitfalls and How to Avoid Them

Patient Reluctance

• Address patient concerns about receiving two injections on the same day (reported as a barrier by 66.0% of HCPs) by explaining the elimination of 14 days of oral medication 3
• Emphasize that tolerability is similar to single-injection regimens despite the higher initial dose 2, 3

Dosing Errors

• Do not reduce the dose below 400 mg per injection for the TIS regimen, as this is based on population pharmacokinetic modeling approved by regulatory agencies 2
• Ensure both injections are administered on the same day, not sequentially over multiple days 4, 1, 2

Monitoring Timeline

Initial Assessment (Day 1)

• Assess baseline extrapyramidal symptoms and akathisia before administration 5, 6
• Document baseline weight and metabolic parameters 6

Early Follow-Up (Weeks 1-4)

• Monitor weekly for akathisia and extrapyramidal symptoms during the first month 5, 1
• Assess for any injection site reactions, though these are typically mild 2

Therapeutic Response Evaluation (Week 4)

• Significant symptom improvement should be evident by week 4; if not present, reassess diagnosis and adherence 7
• Use standardized scales (BPRS, CGI-S) to objectively measure response 1

Special Populations

Adolescents

• The two-injection start has been used successfully in adolescents (16 years old) with schizophrenia, showing good efficacy and tolerability 4
• However, aripiprazole LAI remains off-label in adolescents in most jurisdictions despite oral aripiprazole approval for ages 13-17 4

Patients with Substance Use Disorders

• TIS shows equivalent efficacy and safety in patients with comorbid substance use disorders compared to those without 1