Naltrexone for Impulse Control Disorders in Parkinson's Disease
This study will evaluate the effectiveness of naltrexone in reducing ICD symptoms in Parkinson's disease patients taking a dopamine agonist.
Impulse Control Disorder
|Study Design:||Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Outcomes Assessor)
Primary Purpose: Treatment
|Official Title:||Randomized, Double-blind, Placebo-controlled Study of Naltrexone for Impulse Control Disorders in Parkinson's Disease|
- Percentage of Participants Assessed as Very Much Improved or Much Improved Based on the Clinical Global Impression-Improvement (CGI-I) Scale [ Time Frame: The CGI-I was administered at Visit 2 (week 2, two weeks after baseline) and Visit 5 (week 8, termination visit 8 weeks after baseline). ] [ Designated as safety issue: No ]
The Clinical Global Impression-Improvement scale rates total improvement on a 7 point scale:
- = Very much improved
- = Much improved
- = Minimally improved
- = No change
- = Minimally worse
- = Much worse
- = Very much worse
A participant scoring a 1 or 2 is considered a responder on the CGI scale. For the change in response status over time, a generalized estimating equation (GEE) model was used.
- Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease - Rating Scale (QUIP-RS) [ Time Frame: The QUIP-RS was administered at baseline and the termination visits (Visit 5, 8 weeks after baseline). ] [ Designated as safety issue: No ]The Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease-Rating Scale (QUIP-RS) was developed for use in clinical trials and added as a secondary outcome measure for assessment of change in severity of ICD symptoms, to be completed at baseline and end of study only. For the QUIP-RS, scores for each compulsive behavior range from 0 to 16, with a higher score indicating greater severity (frequency) of symptoms. Given that ICD symptoms are frequently comorbid in patients with PD, total QUIP-RS ICD scores (range from 0 to 64) were used to compare overall severity of ICD symptoms. Please note that this measure is reporting a change from baseline.
|Study Start Date:||November 2009|
|Study Completion Date:||December 2012|
|Primary Completion Date:||December 2012 (Final data collection date for primary outcome measure)|
Active Comparator: Naltrexone
For the first four weeks of the study, participants were administered naltrexone at 50mg per day. Participants not in response at week 4 were increased to 100mg per day for the remaining four weeks of the study.
50-100 mg qd for 8 weeks
Other Name: Revia, Vivitrol
Placebo Comparator: Placebo
Participants received the placebo treatment which looked identical to active study medication.
50-100 mg qd for 8 weeks
Other Name: Placebo
Impulse control disorders (ICDs), including compulsive gambling, sexual behavior, buying, and eating, are increasingly recognized as a significant clinical problem in Parkinson's disease (PD), occurring in up to 15% of patients. Dopamine agonist (DA) treatment is thought to be the primary risk factor for the development of ICDs in PD. ICDs often lead to significant impairments in psychosocial functioning, interpersonal relationships, and quality of life. The management of ICDs in the context of PD can be complex. Patients may be reluctant to discontinue DA treatment due to the motor benefits derived from treatment, so patients often have chronic symptoms. Thus, additional treatment approaches are needed.
A medication shown to be efficacious for the treatment of ICDs with minimal impact on parkinsonism would allow many ICD patients to continue on full-dose DA treatment. Naltrexone, a long-acting opioid receptor antagonist, helps in the treatment of alcohol and opioid dependence. In addition, placebo-controlled studies have demonstrated that it helps in the treatment of pathological gambling in the general population. Opioids regulate dopamine pathways in areas of the brain linked with impulse control disorders, and opioid antagonists block opioid receptors in these regions. In this study, 48 PD patients with an ICD will be treated either with naltrexone (50-100 mg/day) or placebo for a period of 8 weeks. The study will assess if naltrexone improves ICD symptoms in PD and is well tolerated. To our knowledge, the proposed study is the first controlled trial of an agent to treat ICDs in PD.
Please refer to this study by its ClinicalTrials.gov identifier: NCT01052831
|United States, Pennsylvania|
|University of Pennsylvania|
|Philadelphia, Pennsylvania, United States, 19104|
|Principal Investigator:||Daniel Weintraub, MD||University of Pennsylvania|