The Effect of Horizant (Gabapentin Enacarbil) on Augmentation

Restless Legs Syndrome Clinical Trial

— XP-IIT-0034  

Official title:

To Examine the Effect of Horizant (Gabapentin Enacarbil) in Primary Restless Legs Syndrome (RLS) Patients Who Are on Dopaminergic Agents and Exhibiting Augmentation

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT02642315
• Other study ID #: 2002392
• Status: Completed
• Phase: N/A
• Start date: January 2016
• Est. completion date: May 6, 2019

Study information

• Verified date: February 2022
• Source: University of Missouri-Columbia
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

Restless Legs Syndrome (RLS) is a common neurological disorder. Augmentation is the main complication during long-term DA treatment of RLS. This study aims to examine effect of Horizant (Gabapentin Enacarbil) on Augmentation in RLS patients.

Description:

This is an Open label single arm study. The purpose of the study is to demonstrate the efficacy of Horizant in patients with RLS who exhibit augmentation while on Dopaminergic therapy. Adult patients (age 18-85 years) with diagnosis of primary RLS (diagnosed by study investigators) with augmentation on dopaminergic therapy will be screened for participation in the study. RLS diagnosis will be made by the study investigators using International RLS study group criteria. Patients with augmentation on dopaminergic therapy as defined by NIH 2007 with ASRS of 5 to 15 will be offered to participate in the study. Inclusion and exclusion criteria are listed below. The study will be performed after approval of the Institutional Review Board of the University of Missouri.

A total of 50 subjects will be entered into the study over a period of 1 year. Written consent will be obtained from all patients. After pre-participation evaluation for eligibility, subjects will be selected and enrolled in the study and followed for a total of 6 follow up visits (Days 0, 30, 90, 120, 180, 360). Subjects Enrollment period will last up to 12 months. The total duration of study will be 24 months.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 10
• Est. completion date: May 6, 2019
• Est. primary completion date: May 6, 2019
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years to 85 Years

Eligibility

Inclusion Criteria:

1. Adult patients with diagnosis of RLS for more than one year.

2. Patients who are on DA therapy for 6 months or longer.

3. Patients who developed Augmentation (on stable dose of DA) lasting for 3 months or longer.

4. Augmentation severity rating scale of 5 to 15.

5. Both males and females

6. Age range = 18-85 year

Exclusion Criteria:

• Known Hypersensitivity to Horizant or Gabapentin products

• Peripheral neuropathy

• Radiculopathy

• Peripheral vascular disease

• Uremia [abnormal blood urea nitrogen (BUN) or Creatinine on Comprehensive Metabolic Panel (CMP)]

• Anemia

• Patients who are currently pregnant

• Patients who currently take opioids, lithium, anti-nausea medications (e.g. metoclopramide), dopaminergic antagonists (e.g. Haloperidol), 1st generation antihistamines (e.g. diphenhydramine, pseudoephedrine), anti-psychotic medications and iron therapy.

• Subjects with impaired decision making capability.

Related Conditions & MeSH terms

• Psychomotor Agitation
• Restless Legs Syndrome
• Syndrome

Intervention

Drug:
• Horizant
Phase1: During phase 1 therapy, Horizant will be added on as an adjunct to all subjects taking part in the study along with stable dose of their current dopaminergic (DA) agent and both medication will be continued for a total period of 90 days from day 0 to day 90. Subjects will be evaluated for three visits (days 0, 30 and 90) during Phase I. Phase 2: At the 90th day follow-up visit, with initiation of phase 2 therapy, all subjects will be tapered off (by 50% reduction in dose each week) of their current dopaminergic agents while maintaining the same dose of Horizant and will be on Horizant monotherapy. All subjects will be evaluated for additional three clinic visits (days 120, 180, 360).

Locations

Country	Name	City	State
United States	University of Missouri Health Care	Columbia	Missouri

Sponsors (1)

Lead Sponsor	Collaborator
University of Missouri-Columbia

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Change in Augmentation Severity From Day 0 to Day 90	Augmentation severity rating scale; 0-24, 0 is better, 24 is worst	From Day 0 (Baseline) to Day 90
Secondary	Change in Augmentation Severity Rating Scale Form Day 0 to Day 360 (270 Days After Discontinuation pf Dopaminergic Medication)	Numeric Scale to assess degree of augmentation; Range 0-24; 0 is better, 24 is worst.; We compared the Augmentation severity scale on day 0 to day 360 (which is 270 days after this decrease of dopaminergic medication)	Day 0 to day 360 (270 days after discontinuing dopaminergic medication)