Safety and Efficacy Study of IPX159 in Restless Legs Syndrome (RLS)

This study has been completed.
Information provided by (Responsible Party):
IMPAX Laboratories, Inc. Identifier:
First received: January 23, 2012
Last updated: September 8, 2015
Last verified: September 2015
The purpose of this study is to determine whether IPX159 is safe and effective in treating symptoms of RLS in subjects with Restless Legs Syndrome.

Condition Intervention Phase
Restless Legs Syndrome
Drug: IPX159
Drug: Placebo
Phase 2

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: A Randomized, Double-Blind, Placebo-Controlled Safety and Efficacy Study of IPX159 in the Treatment of Moderate to Severe Restless Legs Syndrome (RLS)

Resource links provided by NLM:

Further study details as provided by IMPAX Laboratories, Inc.:

Primary Outcome Measures:
  • International Restless Legs Syndrome Study Group (IRLSSG) Rating Scale [ Time Frame: Assessed at each study visit (visits 1-7), an expected average of 11 weeks ] [ Designated as safety issue: No ]

Enrollment: 159
Study Start Date: November 2011
Study Completion Date: February 2013
Primary Completion Date: February 2013 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: IPX159
IPX159 90 mg daily at week 1 with titration to 180 mg daily at week 2 with possible titration to 270 mg daily at week 3.
Drug: IPX159
Placebo Comparator: Sugar Pill
IPX159 90 mg matching placebo daily at week 1 with titration to 180 mg matching placebo daily at week 2.
Drug: Placebo


Ages Eligible for Study:   18 Years to 70 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  1. Able to understand and willing to sign an informed consent form (ICF) and Health Insurance Portability and Accountability Act (HIPAA) authorization
  2. Males and females aged 18-70 with a history of primary RLS for ≥6 months prior to screening
  3. Symptoms of RLS by medical history on at least 15 nights during the month prior to Screening
  4. BMI 18.5-32
  5. Negative alcohol and drug abuse screen
  6. Negative serum pregnancy test
  7. Agrees to use a medically acceptable method of contraception throughout the study and for 2 months after completing the study.
  8. Able and willing to comply with the protocol, including availability for all scheduled clinic visits and telephone calls.

Exclusion Criteria:

  1. Subjects who use or intend to use post screening the following medications or medication categories:

    • Sedative hypnotics, trazodone
    • Dopamine agonists, gabapentin, gabapentin encarbil, pregabalin
    • Narcotic analgesics, other opioids, tramadol, cyclobenzaprine
    • Iron supplementation therapy
  2. History of HIV, hepatitis B or C
  3. Pregnant or breastfeeding.
  4. History of or clinical signs of any form of epilepsy or seizures, excluding fever-related seizures in childhood.
  5. History or presence of glaucoma
  6. Planning to take herbal medications (eg, hypericum perforatum [St John's Wort], licorice, ephedra, ginkgo, ginseng) during the study.
  7. Use of any investigational drug within the last 30 days or within a period of 5 times the drug's half-life, whichever is longer
  8. Subjects who, in the opinion of the Investigator, should not participate in the study or are not capable of following the study schedule for any reason
  9. Employees or family members of the Investigator, study site, the Sponsor, or Contract Research Organization (if any)
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT01521663

  Show 38 Study Locations
Sponsors and Collaborators
IMPAX Laboratories, Inc.
Principal Investigator: Impax Study Director Impax Laboratories, Inc., acting through its Impax Pharmaceuticals Division (Impax)
  More Information

No publications provided

Responsible Party: IMPAX Laboratories, Inc. Identifier: NCT01521663     History of Changes
Other Study ID Numbers: IPX159-B11-02
Study First Received: January 23, 2012
Last Updated: September 8, 2015
Health Authority: United States: Food and Drug Administration

Keywords provided by IMPAX Laboratories, Inc.:
Moderate to severe idiopathic RLS

Additional relevant MeSH terms:
Psychomotor Agitation
Restless Legs Syndrome
Mental Disorders
Nervous System Diseases
Neurobehavioral Manifestations
Neurologic Manifestations
Pathologic Processes
Psychomotor Disorders
Signs and Symptoms
Sleep Disorders
Sleep Disorders, Intrinsic processed this record on November 30, 2015