R-(-)-deprenyl as a possible protective agent in Parkinson's disease.

The selective monoamine oxidase (MAO) B inhibitor L-deprenyl (Eldepryl, Jumex, Movergan, Selegiline) has gained acceptance as a useful form of adjunctive therapy in the treatment of Parkinson's disease. It has recently been suggested that deprenyl might be effective in altering the course of Parkinson's disease by actually slowing its progression. The rationale for this "new therapeutic strategy" rests on several lines of evidence which can be categorized as theoretical, experimental and empirical. We present details of an "in progress" double-blind, placebo-controlled, prospective clinical drug trial using deprenyl in patients with early, untreated Parkinson's disease. This study is designed to directly test the hypothesis that deprenyl may be effective in favorably altering its natural history. Rigorously testing this new hypothesis could have a major impact on current concepts regarding the treatment and management of Parkinson's disease.