State-of-the-art pharmacological approaches to reduce chorea in Huntington's disease.

Introduction Chorea is a common motor manifestation of Huntington's disease (HD). Two vesicular monoamine transporter type 2 (VMAT-2) inhibitors have been approved by the FDA for treatment of HD chorea, and a third is currently being assessed in a phase 3 trial. Antipsychotic therapies are used off-label for treatment of chorea and can treat comorbid psychiatric symptoms. There is considerable clinical equipoise regarding the safe and effective treatment of chorea and comorbid symptoms in HD.Areas covered: The authors review existing medications used to treat HD chorea in the United States of America (USA). Implications for common comorbid symptoms (e.g. psychiatric, metabolic) are also discussed. Available therapies vary widely in cost, dosing frequency, and off -target effects, both beneficial or negative.Expert opinion: Treatment considerations for chorea should account for patient comorbidities. The authors recommend prospective, observational clinical effectiveness studies which can evaluate the long-term comparative effectiveness and safety of VMAT-2 inhibitors and antipsychotics in HD. Data regarding safety of dual therapy is another critical need. This is especially timely given the changing landscape of HD therapies which may increase cost burden and possibly extend both asymptomatic and symptomatic years for HD patients.