Clinical Coordination Center for STEADY-PD3

The purpose of this study is to establish the efficacy of isradipine 10 mg daily to slow the progression of Parkinson's disease (PD) disability. We propose to conduct a 36-month Phase 3 parallel group placebo controlled study of efficacy of isradipine 10mg daily versus placebo to slow the progression of PD disability in 336 participants with early PD. The study will include interim futility analysis thus eliminating the need to complete a standalone futility study. The proposed study is designed to address two specific aims. First, to establish the efficacy of isradipine 10 mg daily to slow the progression of PD disability as measured by the change in the Unified Parkinson Disease Rating Scale (UPDRS) Part I-III score over 36 months. Second, to ascertain the effect of isradipine 10 mg daily on the progression of PD over 36 months as measured by a number of clinically meaningful and widely accepted measures of progression of disability in early PD. The Clinical Site, under the direction of the Site Principal Investigator, will be responsible for the screening, recruitment, enrollment, and 36-month follow-up of participants with early PD per the study protocol. The Site Principal Investigator's will assume the overall responsibility for the conduct of the study and agrees to adhere to the following Good Clinical Practice principles: • Conduct the study in accordance with the relevant current protocol • Personally conduct or supervise the activities for the protocol • Obtain IRB/EC approval per institutional guidelines • Agree to report adverse events according to the protocol • Read and understand the drug label and associated risks of the study drug • Ensure all study staff assisting in the conduct of the study are trained and informed about their obligations for the protocol • Agree to maintain adequate and accurate records including regulatory documents per Good Clinical Practice guidelines • Agree to make study records available for on-site inspections