This study focuses on neurochemical changes in the brain that occur in Parkinson's disease. In particular we will be looking a neurotransmitter called GABA. In some Parkinson's disease patients we see too much GABA activity in the brain. This target engagement study examines the target engagement effect of GABA-A receptor modulation by transdermal flumazenil (previously clarithromycin). [11C]-flumazenil Positron Emission Tomography (PET) imaging results will be used to assess for possible GABA-A receptor target engagement effects of transdermal flumazenil (previously clarithromycin). Note [11C]Flumazenil GABA-A receptor PET was not performed as part of the transdermal flumazenil study because of a Covid pandemic research amendment.
The arm of this study evaluates possible GABA-A receptor target engagement effects of the FDA-approved medication, transdermal flumazenil (added 4/2020, replaced clarithromycin), in the setting of Parkinson's disease. Half of the subjects will receive transdermal flumazenil for 7-10 days, and half will receive a placebo. [11C]Flumazenil GABA-A receptor PET imaging will be used to assess target engagement effects. Note [11C]Flumazenil GABA-A receptor PET was not performed as part of the transdermal flumazenil study because of a Covid pandemic research amendment.