This article discusses the need for biomarkers and surrogate endpoints for future clinical
trials in individuals at risk for Huntington's disease. Definitions and criteria are presented for
biomarkers and surrogate endpoints, and data are presented suggesting that striatal
volumes, as measured on MRI scans, meet the criteria for a biomarker. Biomarkers can be
used in lieu of clinical endpoints in treatment trials if there is evidence that treatment affects
the biomarker in a way that is predictive of endpoint status. Because there are currently no …