Abilify Asimtufii Injection for Schizophrenia and Bipolar I Disorder Maintenance Therapy

Abilify Asimtufii is an extended-release injectable suspension containing aripiprazole, used for long-acting treatment delivered by intramuscular injection in the gluteal muscle. It is designed for maintenance therapy administered once every two months to support management of certain psychiatric conditions in adults.

Abilify Asimtufii is approved for the treatment of schizophrenia in adults and for maintenance monotherapy treatment of bipolar I disorder in adults. It is not approved for treatment of dementia-related psychosis.

Aripiprazole

Aripiprazole is classified as an atypical antipsychotic. It works by modulating the activity of dopamine and serotonin receptors in the brain, which helps regulate mood, behavior, and thinking associated with schizophrenia and bipolar I disorder.

General Dosing

The recommended dose of Abilify Asimtufii is 960 mg administered by intramuscular injection in the gluteal muscle once every two months (56 days after the previous injection). Dose reduction to 720 mg once every two months may be considered for patients who experience adverse reactions or are known CYP2D6 poor metabolizers.

Initiating Treatment

• For aripiprazole-naïve patients: Tolerability must be established with oral aripiprazole prior to starting Abilify Asimtufii, which may take up to two weeks due to the long half-life of the drug.
• Patients switching from oral antipsychotics: Either a 1-day initiation involving one 960 mg injection of Abilify Asimtufii, one 400 mg injection of Abilify Maintena in a separate muscle, plus a single oral 20 mg aripiprazole dose OR a 14-day initiation with the first 960 mg injection plus 14 days of concurrent oral aripiprazole (10-20 mg) or current oral antipsychotic treatment.
• Patients on Abilify Maintena: Abilify Asimtufii 960 mg may be administered in place of the next scheduled Abilify Maintena dose.

Missed Doses

• If more than 8 weeks but less than 14 weeks have passed since the last injection, give the next dose as soon as possible and resume the 2-month schedule.
• If more than 14 weeks have passed since the last dose, reinitiate treatment with 1-day or 14-day initiation regimens as above.

Cytochrome P450 Considerations

• For known CYP2D6 poor metabolizers or patients taking strong CYP2D6 or CYP3A4 inhibitors for longer than 14 days, the recommended dose is reduced to 720 mg every 2 months.
• Concomitant use with both strong CYP2D6 and CYP3A4 inhibitors or strong CYP3A4 inducers should be avoided.
• If inhibitors are discontinued, the dose of Abilify Asimtufii may need to be increased back to the original dose.

Administration

• Administer by gluteal intramuscular injection only by a healthcare professional.
• Use appropriate needle size based on patient body type (22-gauge, 1.5-inch for non-obese; 21-gauge, 2-inch for obese).
• Do not administer by any other route and do not massage the injection site.

Abilify Asimtufii is contraindicated in patients with known hypersensitivity to aripiprazole or any of the formulation's excipients.

Increased Mortality Risk in Elderly Patients with Dementia-Related Psychosis

Elderly patients with dementia-related psychosis treated with antipsychotics, including aripiprazole, have an increased risk of death, often from cardiovascular or infectious causes. Abilify Asimtufii is not approved for this population.

Serious Potential Reactions

• Cerebrovascular adverse reactions: Increased risk of stroke and transient ischemic attacks in elderly patients with dementia-related psychosis.
• Neuroleptic Malignant Syndrome (NMS): A rare, potentially fatal condition with symptoms including high fever, muscle rigidity, altered mental status, and autonomic instability. Discontinue treatment immediately if suspected.
• Tardive Dyskinesia: Potentially irreversible involuntary movements, risk increases with longer treatment and higher cumulative doses.
• Metabolic changes: Monitoring is recommended for hyperglycemia, diabetes mellitus, dyslipidemia, and weight gain.
• Compulsive behaviors: Cases of pathological gambling and other compulsive behaviors have been reported; dose reduction or discontinuation may need consideration.
• Orthostatic hypotension and syncope: Monitor blood pressure and heart rate especially in patients with cardiovascular risks or dehydration.
• Blood dyscrasias: Perform complete blood counts in patients with history of leukopenia or neutropenia.
• Seizures: Use with caution in patients with seizure history or conditions that lower seizure threshold.
• Cognitive and motor impairment: Patients should exercise caution when driving or operating machinery.

Hypersensitivity reactions including rash, pruritus, urticaria, and rarely anaphylaxis have been reported. There may be other side effects typical of atypical antipsychotics; they are not detailed here.

Important Drug Interactions

• Concomitant use with strong CYP2D6 or CYP3A4 inhibitors requires dose reduction to 720 mg every two months.
• Use with both strong CYP2D6 and CYP3A4 inhibitors or strong CYP3A4 inducers should be avoided.
• If strong enzyme inhibitors are discontinued, dosage may need to be increased.

Store Abilify Asimtufii pre-filled syringes in their original packaging. Prior to administration, visually inspect for discoloration or particulate matter; do not use if present.