Valbenazine has been approved by the U.S. Food and Drug Administration for treatment of tardive dyskinesia. The drug, marketed under the brand name Ingrezza by Neurocrine Biosciences, becomes the first medication approved for treating the condition.
Tardive dyskinesia (TD) is a difficult-to-treat and often incurable form of dyskinesia, a disorder resulting in involuntary, repetitive body movements. In this form of dyskinesia, the involuntary movements are tardive, meaning they have a slow or belated onset. This neurological disorder most frequently occurs as the result of long-term or high-dose use of antipsychotic drugs.
Mitchell Mathis, M.D., director of the Division of Psychiatry Products in the FDA’s Center for Drug Evaluation and Research, said:
“Tardive dyskinesia can be disabling and can further stigmatize patients with mental illness. Approving the first drug for the treatment of tardive dyskinesia is an important advance for patients suffering with this condition.”
Valbenazine, a selective vesicular monoamine transporter 2 (VMAT2) inhibitor, was approved based on data from the Kinect 3 study, a Phase III, randomized, double-blind, placebo-controlled, parallel-group, fixed-dose study comparing once-daily valbenazine 80mg and 40mg to placebo over six weeks in patients with underlying schizophrenia, schizoaffective disorder or mood disorder.
After six weeks, participants who received valbenazine had improvement in the severity of abnormal involuntary movements compared to those who received placebo.
“A treatment for tardive dyskinesia is a welcome and exciting step in the continued effort to destigmatize mental health conditions. With an FDA approved treatment now available, individuals and doctors can have more productive and proactive conversations about TD.”
Valbenazine inhibits VMAT2 and is thought to work by reducing the amount of dopamine released in a region of the brain that controls movement and motor function, helping to regulate nerve signaling in adults with TD. VMAT2 is a protein in the brain that packages neurotransmitters, such as dopamine, for transport and release in presynaptic neurons.
Apart from the underlying psychiatric disorder, tardive dyskinesia may cause afflicted people to become socially isolated. It also increases the risk of dysmorphophobia and can even lead to suicide. Emotional or physical stress can increase the severity of dyskinetic movements, whereas relaxation and sedation have the opposite effect.