Primary Objectives:~There are two main study goals. First, the investigators will determine the safety of a 48 week regimen of Leukine administered as a weight-based dose at 3 µg/kg/day for 5 days, followed by a 2-day holiday. This 48 weeks (n=10) pilot study will continue to assess the safety of Leukine for treatment of Parkinson's disease (PD). Clinical signs and symptoms will be measured by personal well-being, physical, and neurological examinations (UPDRS Parts I, II, III, and IV assessments) and blood tests (CBC with differential, total T cell count, and a comprehensive metabolic sera panel). Due to fragility of the patient population and prior recorded adverse events the proposed dose reductions are justified. Second, in future preparations for an intended broader number of patient enrollments, the investigators wish to functionally examine any or all putative relevant biomarker assessments.~Secondary Objectives:~The investigators will examine over a time of 48 weeks, effects of treatment on defined adaptive immune deficits in PD as measured by analysis of peripheral blood mononuclear cells collected before and during Leukine therapy. The investigators will assess the individual T cell parameters that include links between T cell function and subset analyses and clinical neurological signs and symptoms. These immune parameters will be serially examined as they may contribute to the immune deficits in PD. Thus, timed analyses of changes in T cell phenotypes and/or function will be completed. In addition, the investigators will assess the functional stability of the immune deficits in PD. To this end, the investigators will examine T cell subsets in PD patients in this study against prior results. The investigators will determine whether the immune deficits of PD are consistent during baseline data collection. The investigators will evaluate the potential Leukine-induced motor control and mobility improvements by assessing UPDRS part I, II, III, and IV scores of treatment and on treatment. Additionally, over the course of this 48 week treatment study, investigators will also be assessing various biomarkers within plasma, peripheral blood, and the total lymphocyte and monocyte populations isolated from leukapheresis before Leukine therapy and after 24 and 48 weeks of treatment. Identified biomarkers will be correlated to disease severity and progression as assessed by UPDRS. Serum will also be collected to determine the generation of anti-drug neutralizing antibodies that may develop due to the dosing scheme.
Investigators will evaluate the safety of a 48 week regimen of Leukine administered as a weight-based dose at 3 ug/kg/ day for 5 days followed by a 2-day holiday. This 48 week long study will extend the prior biomarker evaluations observed in a previous study. Clinical signs and symptoms will be measured by personal well-being, physical, and neurological examinations (UPDRS Parts I, II, III, and IV assessments) and blood tests (CBC with differential, total T cell count, and a comprehensive metabolic sera panel). Leukapheresis will be performed to collect large numbers of immune cells for biomarker testing and immune phenotyping. Additionally, the investigators will determine whether immune deficits of PD are consistent during baseline data collection, and the potential Leukine-induced motor control and mobility improvements will be determined by UPDRS part I, II, III, and IV scores off treatment and on treatment.