Double‐Blind, Randomized, Placebo‐Controlled Trial of DA‐9701 in Parkinson's Disease: PASS‐GI Study

OBJECTIVES: This study aimed to assess the efficacy of DA‐9701 on gastrointestinal symptom‐related quality of life in patients with Parkinson's disease on stable dopaminergic medications. METHODS: This multicenter, double‐blind, placebo‐controlled, phase 4 trial included a total of 144 patients with Parkinson's disease with gastrointestinal dysfunctions based on predefined criteria. Participants were randomized to take either DA‐9701 or placebo for 4 weeks, and then both groups were administered DA‐9701 for an additional 8 weeks while antiparkinsonian medications were unchanged. The primary outcome measure was gastrointestinal symptoms and related quality‐of‐life changes assessed on the Korean Nepean dyspepsia index after 4 and 12 weeks of therapy. We also evaluated the impact of DA‐9701 therapy on parkinsonian motor symptoms at each time point. RESULTS: The gastrointestinal symptom‐related quality‐of‐life score significantly improved in the DA‐9701‐treated group compared with the placebo‐treated group after 4weeks (adjusted P = 0.012 by linear mixed effect model analysis). The overall gastrointestinal symptom and dyspepsia sum scores improved at 12 weeks after intervention in the DA‐9701‐first treated group (adjusted P = 0.002 and 0.014, respectively) and also in the placebo‐first treated group (adjusted P = 0.019 and 0.039) compared with the baseline. Parkinsonian motor severity was not significantly affected by DA‐9701 treatment in both groups at 4 and 12 weeks after intervention. There were no drug‐related serious adverse events throughout the trial. CONCLUSIONS: DA‐9701 therapy improved gastrointestinal symptom‐related quality of life, and 12 weeks of daily administration can relieve the overall severity of gastrointestinal symptoms in patients with Parkinson's disease without affecting motor symptoms. (Clinical trial identifier: NCT02775591.) © 2020 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.