Deprenyl and tocopherol antioxidative therapy of parkinsonism (DATATOP). Parkinson Study Group

DATATOP is a double-blind, multi-center, placebo-controlled clinical trial aimed at slowing the decline of patients who are in the early stages of Parkinson's disease (PD). The specific aim is to determine whether or not chronic administration of deprenyl 10 mg per day and/or tocopherol 2000 IU per day to early, otherwise untreated PD patients will prolong the time until levodopa therapy is required to treat emerging disability. Deprenyl and tocopherol exert antioxidative effects through separate but complementary mechanisms of action. A 2 X 2 factorial design allocates eligible subjects to one of four treatment groups: 1) deprenyl alone, 2) tocopherol alone, 3) deprenyl plus tocopherol, or 4) placebo. Eligible subjects include early PD patients (illness duration less than 5 years and in stages I and II), aged 30 to 79, who are not taking or requiring any anti-PD medications. The major response variable is the time period from randomization until the blinded investigator judges levodopa necessary to treat emerging parkinsonian disability. Randomization is stratified to ensure that treatment assignments are balanced for each blinded investigator. Cerebrospinal fluid is sampled just prior to randomization and one month after washout of experimental medications in order to help distinguish between symptomatic and protective effects of interventions. Based on pilot studies it is estimated that approximately 85% of untreated PD patients will require levodopa within two years and a total sample size of 800 subjects will provide a 95% likelihood for detecting a 10% "survival" difference between experimental medications and placebo.(ABSTRACT TRUNCATED AT 250 WORDS)