How Ingrezza Works for Tardive Dyskinesia and Chorea

Ingrezza (valbenazine) is a first-in-class, highly selective vesicular monoamine transporter 2 inhibitor (VMAT2) approved in the U.S. and Canada for the treatment of adults with tardive dyskinesia (TD).1 VMAT2 is a protein responsible for transporting neurotransmitters, such as dopamine, serotonin, and norepinephrine, into synaptic vesicles for storage and release.2 By selectively inhibiting VMAT2, Ingrezza is thought to reduce the levels of these neurotransmitters in the synapse, thereby improving the symptoms of TD and chorea.

Tardive Dyskinesia

TD is a movement disorder that can develop after long-term use of antipsychotic medications. It is characterized by involuntary, repetitive movements of the face, mouth, and limbs.3 The exact mechanism by which antipsychotics cause TD is not fully understood, but it is thought to involve an imbalance of neurotransmitters, including dopamine.4

In TD, there is an increased release of dopamine in the striatum, a region of the brain involved in movement control. This increase in dopamine levels can lead to the involuntary movements characteristic of TD.5 Ingrezza is thought to reduce the symptoms of TD by blocking the reuptake of dopamine into the synaptic vesicles in the striatum, thereby decreasing the amount of dopamine available for release.

Chorea

Chorea is a movement disorder characterized by involuntary, irregular, and unpredictable movements of the face, trunk, and limbs. It can be caused by a variety of underlying conditions, including Huntington's disease, Parkinson's disease, and stroke.6

The exact mechanism by which Ingrezza works in chorea is not fully understood, but it is thought to involve a similar mechanism to that of TD. In chorea, there is also an imbalance of neurotransmitters, including dopamine, in the striatum.7 Ingrezza is thought to reduce the symptoms of chorea by blocking the reuptake of dopamine into the synaptic vesicles in the striatum, thereby decreasing the amount of dopamine available for release.

Ingrezza is a safe and effective treatment for TD and chorea. It is well-tolerated and has a low risk of side effects. Common side effects include headache, nausea, dizziness, and sleepiness. Ingrezza is contraindicated in patients with a history of neuroleptic malignant syndrome (NMS) or untreated or uncontrolled narrow-angle glaucoma.