Modafinil for Freezing of Gait (FOG) in Parkinson's Disease (PD)

Freezing of gait is a late stage complication of Parkinson's disease in which patients note that their feet feel stuck or glued to the ground. This can lead to imbalance and falls and the secondary complications that can result from falls such as fractures and hospitalizations. While levodopa can help freezing of gait in some patients, it does not help in all, and the dose needed to treat freezing may be limited by side effects of the medications. Currently there are no treatments targeted towards freezing of gait and the goal of this research is to see if Modafinil could be one such drug to help freezing of gait in Parkinson's disease. Approximately 20 subjects aged 18 or older with idiopathic Parkinson's disease with freezing of gait will be asked to enroll in the study from the patient population in the movement disorders clinic at the University of Arkansas for Medical Sciences (UAMS). Subjects will be assigned randomly 1:1 to an early start and delayed start arm of the study. In the early start arm subjects will receive 24 weeks of 50 mg oral daily Modafinil while subjects in the delayed start arm will receive 12 weeks of placebo followed by 12 weeks of 50 mg oral daily Modafinil. Assessments will be performed prior to initiation of medication at the screening visit, as well as at 12 weeks of the treatment phase. The assessments will include questionnaires to determine the frequency and severity of freezing of gait, level of mood, anxiety and apathy and quality of life, physical examination and tests of cognitive function. Objective assessment of patients walking will be conducted using a pressure sensor impregnated mat at each visit.