DURSO ET AL
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relate to our small number of study subjects, which al-
lowed for only large differences to be detected. The
possibility that clinical differences might have been
seen in a larger patient group is underscored by re-
cent success in treating PD patients with peripheral
catechol-O-methyltransferase (COMT) inhibitors.20-23
These latter studies clearly demonstrate that further di-
minishing peripheral LD catabolism in patients taking
usual therapeutic CD/LD doses beneficially affects
treatment. The administration of LD in combination
with CD and peripheral COMT inhibitor doses that
maximally inhibit peripheral LD catabolism might ulti-
mately prove the most rational therapy in PD. Such an
approach would theoretically optimize delivery of LD
into the brain and keep unwanted peripheral DA pro-
duction to a minimum.
10. Hardebo JE, Ernson PC, Falck B, Owman C, Rosengren E: En-
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