DATATOP: A Multicenter Controlled Clinical Trial in Early Parkinson's Disease

DATATOP (Deprenyl and tocopherol antioxidative therapy of parkinsonism) is a placebo-controlled clinical trial designed to test the hypothesis that long-term treatment of patients with early Parkinson's disease with deprenyl 10 mg/d and/or tocopherol (vitamin E) 2000 IU/d will extend the time until disability requires therapy with levodopa (primary end point). At 28 US and Canadian sites, 800 eligible patients in the early stages of untreated Parkinson's disease were enrolled in DATATOP and randomized to (1) active deprenyl, (2) active tocopherol, (3) active deprenyl and tocopherol, or (4) placebo treatments. Subjects are being evaluated systematically at regular intervals over 2 years to determine if and when the primary end point of disability is attained. At baseline evaluation, our cohort represented minimally disabled patients with Parkinson's disease who did not require symptomatic anti-Parkinson's disease medications. Despite an almost 2:1 representation of male-female subjects, no selection biases were identified that might confound the primary end-point analysis. This large DATATOP cohort is expected to provide a high likelihood (power) for detecting significant treatment effects, if indeed they exist.