Effect of tetrabenazine on Stroop interference in Huntington's disease: Protocol

Area of Science:

• Neuroscience
• Clinical Neurology
• Pharmacology

Background:

• Huntington's disease (HD) is a neurodegenerative disorder affecting motor, cognitive, and psychiatric functions.
• Tetrabenazine (TBZ) is a VMAT2 inhibitor used to manage chorea in HD.
• Previous studies indicate TBZ can improve visual gating and postural stability in HD patients.

Purpose of the Study:

• To investigate the effect of low-dose tetrabenazine (TBZ) on cognitive processing, specifically visual stimulus masking, in Huntington's disease (HD) patients.
• To determine if partial dopaminergic depletion induced by TBZ can mitigate Stroop interference in HD.
• To evaluate the efficacy of TBZ using the Golden formula derived from Stroop test scores.

Main Methods:

• An open-label, single-arm pilot study involving de novo or withdrawal of tetrabenazine (TBZ) in HD patients.
• Participants underwent the Stroop color naming, word reading, and interference test.
• TBZ (12.5 mg) was administered twice, with the Stroop test repeated 6 hours after the initial baseline test.

Main Results:

• The study endpoint is the Golden formula, calculated from off- and on-TBZ Stroop test raw scores.
• Analysis will focus on changes in Stroop interference scores to assess the impact of TBZ on cognitive masking.
• Results will quantify the effect of partial dopaminergic depletion on visual processing in HD.

Conclusions:

• This study will provide preliminary data on the potential cognitive benefits of low-dose tetrabenazine in Huntington's disease.
• Findings may inform future therapeutic strategies targeting cognitive deficits in HD.
• The Stroop interference test serves as a sensitive measure for evaluating TBZ's impact on visual processing in HD.