Caudate volume as an outcome measure in clinical trials for Huntington’s disease: a pilot study

Previous research has demonstrated that longitudinal change in caudate volume could be observed over a period of 3 years in subjects with Huntington's disease (HD). The current pilot study was designed to determine whether measurement of caudate change on magnetic resonance imaging (MRI) is a feasible and valid outcome measure in an actual clinical trial situation. We measured caudate volumes on pre- and post-treatment MRI scans from 19 patients at two sites who were participating in CARE-HD (Co-enzyme Q10 and Remacemide: Evaluation in Huntington's Disease), a 30-month clinical trial of remacemide and co-enzyme Q(10) in symptomatic patients with HD. Results from this pilot study indicated that decrease in caudate volume was significant over time. Power analysis indicated that relatively small numbers of subjects would be needed in clinical trials using caudate volume as an outcome measure. Advantages and disadvantages of using MRI caudate volume as an outcome measure are presented. We recommend the adoption of quantitative neuroimaging of caudate volume as an outcome measure in future clinical trials for treatments of HD.