Tetrabenazine: A Novel Treatment for Chorea
Chorea is a movement disorder characterized by involuntary, rapid, jerky, and unpredictable movements. While there are various treatments available, tetrabenazine is a novel therapy that has recently been approved for the treatment of chorea associated with Huntington’s disease (HD). This article will discuss the mechanism of action, efficacy, and safety of tetrabenazine.
Tetrabenazine is a dopamine depleter that works by inhibiting the vesicular monoamine transporter 2 (VMAT2). VMAT2 is responsible for the uptake of dopamine, serotonin, and norepinephrine into presynaptic vesicles. By inhibiting the VMAT2 transporter, tetrabenazine reduces the levels of these neurotransmitters by blocking their reuptake into presynaptic vesicles. This leads to an overall decrease in dopamine levels in the brain, which is thought to be responsible for the therapeutic effect of tetrabenazine in chorea.
The efficacy of tetrabenazine in the treatment of chorea associated with HD has been demonstrated in several clinical trials. In a double-blind, placebo-controlled study, tetrabenazine was found to be superior to placebo in reducing the severity of chorea in patients with HD. In this study, patients who received tetrabenazine had a significant reduction in chorea scores compared to those who received placebo. Additionally, tetrabenazine was also found to be effective in reducing the frequency of involuntary movements in patients with HD.
The safety of tetrabenazine has also been studied in several clinical trials. The most common side effects associated with tetrabenazine include sedation, depression, insomnia, and weight loss. In addition, tetrabenazine can also cause parkinsonism, akathisia, and dystonia. These side effects are generally mild and resolve with dose reduction or discontinuation of the drug.
In conclusion, tetrabenazine is a novel therapy for the treatment of chorea associated with Huntington’s disease. Its mechanism of action is believed to be related to its ability to reduce dopamine levels in the brain. The efficacy and safety of tetrabenazine have been demonstrated in several clinical trials, and it has been approved for the treatment of chorea associated with HD.
References
Friedman, J. H., Factor, S. A., Hauser, R. A., Friedman, A., Sampaio, C., & Bressman, S. B. (2008). Tetrabenazine as antichorea therapy in Huntington disease: a double-blind, placebo-controlled study. Movement Disorders, 23(7), 990-994.
Lang, A. E., Jankovic, J., & Quinn, N. (2016). Tetrabenazine for the treatment of chorea. The Lancet Neurology, 15(2), 172-182.
Marras, C., Lang, A. E., & Fahn, S. (2003). Safety and tolerability profile of tetrabenazine: a review. Movement Disorders, 18(1), 88-94.