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A Study to Evaluate the Safety and Tolerability of Arbaclofen Placarbil (XP19986) in Subjects With Acute Back Spasms

This study has been completed.
Information provided by (Responsible Party):
Indivior Inc. Identifier:
First received: January 6, 2009
Last updated: September 9, 2016
Last verified: September 2016
The purpose of the study is to evaluate safety and tolerability of arbaclofen placarbil sustained release tablets taken every 12 hours compared to placebo in subjects with acute back spasms in the lumbar region.

Condition Intervention Phase
Back Pain
Drug: Arbaclofen placarbil, 20 mg
Drug: Placebo
Drug: Arbaclofen placarbil, 30 mg
Drug: Arbaclofen placarbil, 40 mg
Phase 2

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Investigator)
Primary Purpose: Treatment
Official Title: A Randomized, Double-blind, Placebo-controlled Study to Evaluate the Safety and Tolerability of XP19986 in Subjects With Acute Back Spasms

Resource links provided by NLM:

Further study details as provided by Indivior Inc.:

Primary Outcome Measures:
  • Incidence of treatment-emergent adverse events [ Time Frame: 14 Days ] [ Designated as safety issue: Yes ]
    Safety was assessed based on the incidence, intensity and relationship of treatment emergent AEs

Secondary Outcome Measures:
  • Change in pain severity score using the VAS [ Time Frame: 4 Days ] [ Designated as safety issue: No ]

Enrollment: 161
Study Start Date: December 2008
Study Completion Date: July 2009
Primary Completion Date: July 2009 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Arbaclofen placarbil 20 mg
Arbaclofen placarbil 20 mg, BID, for 14 days including the taper period.
Drug: Arbaclofen placarbil, 20 mg
Other Name: XP19986 SR3
Placebo Comparator: Placebo for Arbaclofen placarbil
Placebo for 14 days
Drug: Placebo
Other Name: Sugar Pill
Experimental: Arbaclofen placarbil 30 mg
Arbaclofen placarbil 30 mg, BID, for 14 days including the taper period.
Drug: Arbaclofen placarbil, 30 mg
Other Name: XP19986 SR3
Experimental: Arbaclofen placarbil 40 mg
Arbaclofen placarbil 40 mg, BID, for 14 days including the taper period.
Drug: Arbaclofen placarbil, 40 mg
Other Name: XP19986 SR3 tablets


Ages Eligible for Study:   18 Years to 65 Years   (Adult)
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  1. Acute moderate to severe muscle spasms in the lumbar region, as indicated by a minimum Visual Analog Scale pain severity score of 4.0 cm, beginning either:

    • within four days prior to screening for subjects who do not require a 24-hour washout


    • within three days for subjects who require a 24-hour washout
  2. Willing to discontinue all analgesics (e.g. NSAIDS, COX-2 inhibitors, acetaminophen), aspirin >81 mg/day, short-acting muscle relaxants (i.e. carisoprodol, Soma®), and herbal remedies for pain at least 24 hours prior to first dose and to refrain from use during the study (cardio-protective doses of aspirin ≤ 81 mg /day are allowed).

Exclusion Criteria:

  1. Clinically significant abnormal neurological history or examination at screening (excluding back spasm), including lumbar radicular symptoms, spinal stenosis, foot drop, herniated nucleus pulposus, or other structural defects
  2. Subjects with back spasm related to major trauma to the region
  3. Subjects with muscle spasms due to a work-related injury or subjects involved in any injury-related litigation
  4. Subjects using any of the following medications at screening:

    • Opioids, both short- and long-acting including but not limited to: morphine, fentanyl patch, oxycodone, tramadol)
    • benzodiazepines, such as valium and lorazepam
    • cyclobenzaprine containing drugs (e.g., Flexeril, Amrix)
    • carisoprodol (e.g., Soma®) within 24 hours of screening
  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: NCT00817986

United States, Arizona
Litchfield Park, Arizona, United States, 85340
United States, California
Anaheim, California, United States, 92084
Anaheim, California, United States, 92801
San Diego, California, United States, 92128
Vista, California, United States, 92083
United States, Florida
Fort Lauderdale, Florida, United States, 33306
Miami, Florida, United States, 33143
United States, Georgia
Atlanta, Georgia, United States, 30308
United States, Kansas
Overland Park, Kansas, United States, 66211
United States, Kentucky
Erlanger, Kentucky, United States, 41018
United States, Michigan
Traverse City, Michigan, United States, 49684
United States, New Jersey
Brick, New Jersey, United States, 07732
United States, North Carolina
Raleigh, North Carolina, United States, 27612
Winston-Salem, North Carolina, United States, 27103
United States, Oklahoma
Oklahoma City, Oklahoma, United States, 73122
United States, South Carolina
Anderson, South Carolina, United States, 29621
United States, Texas
Dallas, Texas, United States, 75234
Houston, Texas, United States, 77074
San Antonio, Texas, United States, 78215
United States, Utah
Salt Lake City, Utah, United States, 84106
Sponsors and Collaborators
Indivior Inc.
Study Director: Study Director Indivior Inc.
  More Information

Responsible Party: Indivior Inc. Identifier: NCT00817986     History of Changes
Other Study ID Numbers: XP-B-083 
Study First Received: January 6, 2009
Last Updated: September 9, 2016
Health Authority: United States: Food and Drug Administration
Individual Participant Data  
Plan to Share IPD: No

Keywords provided by Indivior Inc.:
Acute back pain in the lumbar region

Additional relevant MeSH terms:
Back Pain
Neurologic Manifestations
Nervous System Diseases
Signs and Symptoms
Arbaclofen placarbil
Muscle Relaxants, Central
Physiological Effects of Drugs
Neuromuscular Agents
Peripheral Nervous System Agents
GABA-B Receptor Agonists
GABA Agonists
GABA Agents
Neurotransmitter Agents
Molecular Mechanisms of Pharmacological Action processed this record on October 21, 2016