NIPH Clinical Trials Search

A Phase 2 study of naldemedine in participants with constipation associated with Parkinson's disease

Basic Information

Recruitment status	Recruiting
Health condition(s) or Problem(s) studied	Constipation associated with Parkinson's disease
Date of first enrollment	01/05/2026
Target sample size	40
Countries of recruitment
Study type	Interventional
Intervention(s)	Oral administration of naldemedine or placebo

Outcome(s)

Primary Outcome	Change from baseline in the number of SBMs within 24 hours after the first administration.
Secondary Outcome

Key inclusion & exclusion criteria

Age minimum	>= 18age old
Age maximum	< 75age old
Gender	Both
Include criteria	Patients aged 18 to under 75 at the time of obtaining the informed consent form (ICF). Patients diagnosed with Parkinson's disease with a Hoehn-Yahr severity classification of grade 1 to 3. Patients with no significant changes in bowel movements (frequency, etc.) during the 3 months prior to obtaining informed consent, and who rarely experience diarrhea unrelated to laxative use. Patients who experienced 5 or fewer spontaneous bowel movements (SBM ; a bowel movement without the use of a rescue laxative within the previous 24 hours) in the 2 weeks prior to the start of investigational drug administration, and who experienced straining, a feeling of incomplete evacuation, hard stools, or rabbit-pellet-like stools in 25% or more of their bowel movements during that period.
Exclude criteria	Patients whose primary cause of constipation is determined by the principal investigator (or co-investigator) to be other than Parkinson's disease. Patients who have not had a bowel movement in the week prior to obtaining informed consent or in the week prior to the start of investigational drug administration. Patients with gastrointestinal obstruction or suspected gastrointestinal obstruction, or patients with a history of gastrointestinal obstruction and a high risk of recurrence. Patients whose Parkinson's disease treatment has been changed within the 4 weeks prior to obtaining informed consent.