| Completed | 2 | 40 | Europe | Bupropion, Wellbutrin, Budeprion, Prexaton, Elontril, Aplenzin, Placebo, control | Charite University, Berlin, Germany, University of Ulm, Ruhr University of Bochum, University Hospital Muenster | Apathy, Huntington's Disease | 05/14 | 05/14 | | |