What is the fastest dosing regimen for Rexulti (brexpiprazole) in an inpatient setting?

Fastest Dosing Regimen for Rexulti (Brexpiprazole) in Inpatient Setting

The fastest appropriate dosing regimen for Rexulti (brexpiprazole) in an inpatient setting is to start at 1 mg/day for schizophrenia or 0.5-1 mg/day for major depressive disorder, with titration to the target dose of 2-4 mg/day over several days, based on patient response and tolerability. 1

Initial Dosing by Indication

• Schizophrenia: Start with 1 mg once daily, titrate to 2-4 mg/day target dose 1, 2
• Major Depressive Disorder (as adjunct): Start with 0.5-1 mg once daily, titrate to 2 mg/day target dose 1, 3

Titration Schedule for Inpatient Setting

For Schizophrenia:

• Day 1: 1 mg once daily 1
• Day 3-4: Increase to 2 mg once daily (if tolerated) 2, 4
• Day 5-7: Increase to 3-4 mg once daily (if needed and tolerated) 1, 5

For Major Depressive Disorder:

• Day 1: 0.5-1 mg once daily 1
• Day 3-4: Increase to 2 mg once daily (if tolerated) 3, 6

Special Population Considerations

• Hepatic Impairment: Maximum dose should be reduced to 2 mg once daily for MDD and 3 mg once daily for schizophrenia in patients with moderate to severe hepatic impairment 1
• Renal Impairment: Maximum dose should be reduced to 2 mg once daily for MDD and 3 mg once daily for schizophrenia in patients with CrCl < 60 mL/minute 1
• CYP2D6 Poor Metabolizers: Dose adjustments may be required 1

Administration Guidelines

• Can be administered with or without food 1
• Should be taken once daily 1, 2
• Monitor for adverse effects during rapid titration, particularly akathisia 5, 4

Monitoring During Rapid Titration

• Daily assessment of tolerability and symptom response 2, 4
• Akathisia: Most common adverse effect (5.5% in schizophrenia, 8.6% in MDD) 5
• Weight gain: Monitor weight regularly 5
• Sedation/somnolence: Assess for excessive sedation 4

Clinical Considerations for Rapid Titration

• Brexpiprazole has a lower intrinsic activity at D2 receptors compared to aripiprazole, which may translate to lower risk of akathisia during rapid titration 2, 4
• The drug has stronger antihistaminic activity, which may be associated with sedative effects 4
• Efficacy for schizophrenia is highest at the 4 mg/day dose 4

Cautions with Rapid Titration

• Monitor for extrapyramidal symptoms, though these are reported to be less common than with other antipsychotics 2, 5
• Effects on glucose and lipids are generally small but should be monitored 5
• Minimal effects on prolactin and QT interval have been reported 5

While faster titration may be possible in an inpatient setting where close monitoring is available, the FDA-approved dosing schedule should be followed whenever possible to minimize adverse effects while achieving therapeutic benefit 1, 2.