Indications

Deutetrabenazine is a vesicular monoamine transporter 2 (VMAT2) inhibitor indicated for the treatment of- Chorea associated with Huntington's disease Tardive dyskinesia in adults.

Composition

Pharmacology

The precise mechanism by which deutetrabenazine exerts its anti-chorea effects is unknown but is believed to be related to its effect as a reversible depletor of monoamines (such as dopamine, serotonin, norepinephrine, and histamine) from nerve terminals. The major circulating metabolites (α-dihydrotetrabenazine and β-dihydrotetrabenazine) of deutetrabenazine, are reversible inhibitors of vesicular monoamine transporter 2 (VMAT2), resulting in decreased uptake of monoamines into synaptic vesicles and depletion of monoamine stores.

Dosage & Administration

Patients not presently receiving Tetrabenazine: Chorea associated with Huntington’s disease - Initial dose: 6 mg/day Maintenance dose: 6 mg-48 mg/day Maximum dose: 48 mg/day Tardive dyskinesia - Initial dose: 12 mg/day Maintenance dose: 12 mg-48 mg/day Maximum dose: 48 mg/day Titrate up at weekly intervals by 6 mg per day to a tolerated dose that reduces chorea, up to a maximum recommended daily dosage of 48 mg (24 mg twice daily). Administer total daily dosages of 12 mg or above in two divided doses and administer with foods. Patients receiving Tetrabenazine : If switching patients from tetrabenazine, discontinue tetrabenazine and initiate deutetrabenazine the following day. The recommended initial dosing regimen of deutetrabenazine in patients switching from tetrabenazine to deutetrabenazine is shown in below chert: Current Tetrabenazine daily dosage Initial regimen of Deutetrabenazine 12.5 mg 6 mg once daily 25 mg 6 mg once daily 37.5 mg 9 mg once daily 50 mg 12 mg once daily 62.5 mg 15 mg once daily 75 mg 18 mg once daily 87.5 mg 21 mg once daily 100 mg 24 mg once daily After patients are switched to deutetrabenazine, the dose may be adjusted at weekly intervals.

Contraindications

Deutetrabenazine is contraindicated in patients with Suicidal, or untreated/inadequately treated depression, Hepatic impairment and in patients Taking MAOIs, reserpine, or tetrabenazine.

Side Effects

Most common adverse reactions (>8%) of deutetrabenzine’s are somnolence, diarrhea, dry mouth, and fatigue.

Pregnancy & Lactation

There are no adequate data on the developmental risk associated with the use of deutetrabenazine in pregnant women. There are no data on the presence of deutetrabenazine or its metabolites in human milk, the effects on the breastfed infant, or the effects of the drug on milk production.

Precautions & Warnings

Patients may experience Neuroleptic Malignant Syndrome (discontinue deutetrabenazine if this occurs), Akathisia, agitation, restlessness, and Parkinsonism (reduce the daily dose of deutetrabenazine or discontinue if this occurs) and Sedation/somnolence.

Therapeutic Class

Storage Conditions

Keep below 30°C temperature, away from light & moisture. Keep out of the reach of children.