Anna Gawrys, Mercer University College of Pharmacy
Huntington disease (HD) is a neurological disorder that affects cognitive and physical functions. Patients with HD suffer from declining mental abilities, from psychiatric disorders, and physically from jerky, involuntary movements. The symptoms can be managed with medication but the progression of the disease cannot be prevented. American Academy of Neurology for treatment of chorea in patients with HD recommends tetrabenazine, amantadine, or riluzole.
According to the package insert of tetrabenazine, the daily dose must be individualized and it is administered two or three times per day. 
A New Drug Application (NDA) for deutetrabenazine was accepted by the U.S. Food and Drug Administration (FDA) for the treatment of chorea associated with HD. 
Title: Effect of Deutetrabenazine on Chorea Among Patients With Huntington Disease A Randomized Clinical Trial 
|Design||Randomized, double-blind, placebo-controlled study; N= 90|
|Objective||To evaluate efficacy and safety of deutetrabenazine treatment to control chorea associated with HD|
|Study Groups||Deutetrabenazine (n= 45); placebo (n=45)|
|Methods||Adults diagnosed with HD and a baseline total maximal chorea score of eight or higher (range, 0-28; lower score indicates less chorea) were randomized to receive deutetrabenazine or placebo. The active agent was titrated to optimal dose level over eight weeks and maintained for four weeks, followed by a one-week washout.|
|Duration||August 2013 – August 2014|
|Primary Outcome Measure||Total maximal chorea score change from baseline to maintenance therapy
|Baseline Characteristics||Deutetrabenazine (n=45)||Placebo (n= 45)|
|Men, n (%)||22 (49)||28 (62)|
|White, n (%)||45 (100)||38 (84)|
|Cytosine-adenine-guanine (CAG) repeat length, n||43.4||44.3|
|36-Item Short Form (SF-36) physical functioning, mean||47.5||43.2|
|Berg Balance Test, mean||51.3||48.4|
|Results||Unified HD Rating Scale Total Maximal Chorea
|Deutetrabenazine (n=45)||Placebo (n= 45)|
|Baseline, mean (SD)*||12.1 (2.7)||13.2 (3.5)|
|Maintenance, mean (SD)*||7.7 (3.9)||11.3 (4.1)|
|*SD: standard deviation|
|Adverse Events||Common Adverse Events: somnolence (11.1%), dry mouth (8.9%), diarrhea (8.9%)|
|Serious Adverse Events: cholecystitis and agitated depression (2.2%)|
|Percentage that Discontinued due to Adverse Events: 2.2|
|Study Author Conclusions||Among patients with chorea associated with HD, the use of deutetrabenazine compared with placebo resulted in improved motor signs at 12 weeks. Further research is needed to assess the clinical importance of the effect size and to determine longer-term efficacy and safety.|
The treatment for HD includes only a few choices of medications and all of them need to be taken two or three times per day. The level of compliance decreases when medications have to be taken more than once daily. The novel medication, deutetrabenazine, is formulated with deuterium that increases the compound’s half-life and consequently allows for once daily dosing. Deutetrabenazine successfully reduced chorea movements among HD patients and soon may become a viable treatment option. The use of this medication may be limited by its side effect profile. This study had a well-diversified population among men and women however the study limitation is its lack of racial diversity and small number of participants.
- Suchowersky O, Armstrong MJ, Miyasaki J. Evidence-based guideline: pharmacologic treatment of chorea in Huntington disease: report of the Guideline Development Subcommittee of the American Academy of Neurology. Neurology. 2013;80(10):970.
- Tetrabenazine [package insert]. Bridgewater, NJ: Oceanside Pharmaceuticals; 201
- SD-809 (deutetrabenazine) FDA Approval Status – Drugs.com. https://www.drugs.com/history/sd-809.html. Published 2016. Accessed July 22, 2016.
- Frank S, Testa CM, Stamler D, et al. Effect of Deutetrabenazine on Chorea Among Patients With Huntington Disease: A Randomized Clinical Trial. JAMA. 2016;316(1):40-50.