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Tasmar- Good News-Bad News 30 Oct 1998 Two enzymes normally present in the body are enemies of levodopa and/or dopamine, and hence of PD patients: monoamine oxidase (MAO) and catechol-O-methyl transferase (COMT). But both have beneficial functions as well. For years we have enjoyed Eldepryl (selegiline), which inhibits only MAO-B, the kind found in the brain, and not MAO-A, whose inhibition can be dangerous: As a selective inhibitor of MAO-B, Eldepryl exerts some symptomatic benefit in PD, and is thought (hoped?) also to provide protection of vulnerable neurons in the substantia nigra against oxidative stress. Now we have an inhibitor of COMT, tolcapone (Tasmar) to counter the other threat. In both clinical and laboratory studies, Tasmar is seen as a major breakthrough in treatment of PD, by reducing levodopa requirement, raising on time, and other benefits such as antidepression. But a new report* describes experience of 3 elderly patients with long- standing PD, who on starting Tasmar became significantly confused, and recovered only upon stopping the drug. An earlier report** suggested that COMT has a useful role in elimination of certain oxidative toxins, and therefore that Tasmar by blocking COMT might possibly accelerate nigrostriatal degeneration in PD. * Kuhn W et al; Lancet, 17 Oct 1998:1313-1314 ** Colm H, Wilson J; Lancet, 27 Jun 1998:1995-1996 Cheers, Joe -- J. R. Bruman (818) 789-3694 3527 Cody Road Sherman Oaks, CA 91403-5013