The purpose of this study, called MOVE-PD, is to investigate how patients with Parkinson’s disease (PD) and chronic constipation respond to the drug RM-131. The study will evaluate the safety and tolerability of the drug and evaluate whether RM-131 relieves constipation and related uncomfortable abdominal symptoms in patients who are unsatisfied with other therapies. During the course of the study, PD symptoms will also be assessed.
A total of 56 Parkinson’s disease patients will be enrolled. Patients meeting the inclusion criteria will participate in two sequential 14-day study periods in which information on bowel habits and abdominal symptoms will be collected with a daily diary. During these periods, patients will receive either placebo (inactive drug) or 100 micrograms of RM-131 once daily via injection with a very small insulin needle. Every patient will receive placebo in at least one period of the study. After the two periods, patients will be followed for seven days post-treatment to collect information via the same daily diary on bowel function off treatment.
Relevance to Diagnosis/Treatment of Parkinson’s Disease:
Gastrointestinal (GI) disorders are common in Parkinson’s disease; among these are constipation, which can be hard to treat. Constipation can happen when the GI system slows down, which can cause significant discomfort and decrease the body’s ability to absorb medicine used to treat PD. The study drug, RM-131, may help to improve constipation in patients with PD, especially those who are not adequately treated with existing therapies.
The prevalence of constipation in PD is very high, with studies reporting more than 50 percent of PD patients suffering from moderate/severe constipation. Symptom management for PD patients currently relies on fluid and diet management initially, with enemas and laxatives used as second-line therapy. A large proportion of these patients are considered refractory to existing therapy, particularly in later-stage PD. The investigators hope to show that RM-131 has a positive effect on improving the symptoms of constipation in PD, especially among PD patients who do not respond to other treatments.
The MOVE-PD study was stopped early because participation was lower than expected. In the small group of patients studied, the dose of RM-131 used was well tolerated and without serious adverse effects. There were not enough participants in the study for us to learn what we hoped to learn, but some unique and important ideas and new questions surfaced regarding bowel problems in Parkinson’s disease (PD), as constipation may be defined differently in the PD population. Bowel problems are an important problem and current treatments are not always sufficient in addressing these symptoms. Although this study was not completed, the limited results will be published, and may help researchers with future clinical constipation studies in PD.