A Double‐Blind, Randomized, Placebo‐Controlled Trial of Bumetanide in Parkinson's Disease

Abstract Background Acting on the main target of dopaminergic cells, the striatal γ‐aminobutyric acid (GABA)‐ergic cells, might be a new way to treat persons with Parkinson's disease (PD). Objective The objective of this study was to assess the efficacy of bumetanide, an Na–K–Cl cotransporter (NKCC1) inhibitor, to improve motor symptoms in PD. Methods This was a 4‐month double‐blind, randomized, parallel‐group, placebo‐controlled trial of 1.75 to 3 mg/day bumetanide as an adjunct to levodopa in 44 participants with PD and motor fluctuations. Results Compared to the baseline, the mean change in OFF Movement Disorder Society Unified Parkinson's Disease Rating Scale Part III score after 4 months of treatment (primary endpoint) did not improve significantly compared with placebo. No changes between participants treated with bumetanide and those treated with placebo were observed for most other outcome measures. Despite no relevant safety signals, bumetanide was poorly tolerated. Conclusions There was no evidence in this study that bumetanide has efficacy in improving motor symptoms of PD. © 2024 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.