Valbenazine

418.57

418.57

54K37P50KH

Light Yellow to Yellow

N - Nervous system

1.11±0.1 g/cm3(Predicted)

>75°C (dec.)

507.2±50.0 °C(Predicted)

7.76±0.33(Predicted)

Hygroscopic, -20°C Freezer, Under inert atmosphere

|Danger|H301 (100%): Toxic if swallowed [Danger Acute toxicity, oral]|P260, P261, P264, P270, P271, P301+P310, P304+P340, P312, P314, P321, P330, P403+P233, P405, and P501|Aggregated GHS information provided by 3 companies from 1 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

No carcinogenicity, mutagenicity, or impairment of fertility has been observed. QT prolongation may occur with strong CYP2D6 or CYP3A4 inhibitors, or in people who are poor CYP2D6 metabolizers. No overdose information is currently available.

Tetrabenazine has not been associated with rates of serum enzyme elevations greater than occur with placebo therapy, but information on liver test results during therapy is limited and occasional instances of asymptomatic ALT elevations leading to drug discontinuation or dose modification have been reported by the sponsor. In prelicensure pivotal registration trials in several hundred patients, tetrabenazine was not associated with cases of jaundice or hepatitis. Since licensure, there have been no published reports of clinically apparent liver injury, jaundice or hepatitis attributed to tetrabenazine. Thus, clinically apparent liver injury with jaundice due to tetrabenazine must be rare, if it occurs at all.

Valbenazine is >99% bound to plasma proteins. Its active metabolite [+]-α-HTBZ is 64% bound to plasma proteins.

For the treatment of tardive dyskinesia in adults.|FDA Label

The vesicular monoamine transporter type 2 (VMAT2) inhibitors are agents that cause a depletion of neuroactive peptides such as dopamine in nerve terminals and are used to treat chorea due to neurodegenerative diseases (such as Huntington chorea) or dyskinesias due to neuroleptic medications (tardive dyskinesia). As of 2019, three VMAT2 inhibitors have become available in the United States for management of dyskinesia syndromes, each with a somewhat different spectrum of approved indications: tetrabenazine (Xenazine and generics: 2008), deutetrabenazine (Austedo: 2017) and valbenazine (Ingressa: 2017). The VMAT2 inihibitors have not been associated with serum enzyme elevations during therapy or linked to instances of clinically apparent liver injury, but they have had limited general clinical use.

Valbenazine decreases the availability of monoamine neurotransmitters by preventing their storage in synaptic vesicles. This is believed to be the reason behind its therapeutic effect in tardive dyskinesia although the exact mechanism is unknown.

Oral bioavailability of 49%. Tmax of 0.5-1h.|Roughly 60% is excreted in urine and 30% in feces. Less than 2% if the parent compound or active metabolite was excreted unchanged.|92 Liters.|7.2 Liters/hour.

Valbenzine is extensively metabolized to one active metabolite [+]-α-dihydrotetrabenazine ([+]-α-HTBZ) through hydrolysis of the valine ester reaching Cmax within 4-8 hours. It is also metabolized via oxidation by CYP3A4/5 to a mono-oxidzed metabolite NBI-136110 which also appears to pharmacologically active. [+]-α-HTBZ is metabolized by CYP2D6.

Both valbenazine and its active metabolite [+]-α-HTBZ have a half life of 15-22 hours.

Valbenazine and its active meabolites bind to and inhibit vesicular monoamine transporter 2 (VMAT2)with high selectivity (valbenazine Ki = 150nM, [+]-α-HTBZ Ki = 1.98nM, NBI136110 Ki = 160nM) with no significant binding to VMAT1 (Ki <10microM for each). This prevents the reuptake and storage of monoamine neurotransmitters noradrenaline, dopamine, and serotonin in synaptic vesicles making them vulnerable to metabolism by cytosolic enzymes. The presynaptic release of monoamine neurotransmitters is decreased due to the lack of vesicles with packaged neurotransmitter ready for release into the synapse. Neither valbenazine nor its active metabolite exhibit significant off target binding at dopamine, serotonin, or adrenaline receptors or uptake transporters at 10microM concentrations.

(2R,3R,11BR)-9,10-dimethoxy-3-(2-methylpropyl)-1,3,4,6,7,11b-hexahydro-2H- benzo(a)quinolizin-2-yl l-valinate

Human Drugs -> FDA Approved Drug Products with Therapeutic Equivalence Evaluations (Orange Book) -> Active Ingredients