Treatment of Complex Regional Pain Syndrome With Once Daily Gastric-Retentive Gabapentin (Gralise)


The purpose of this study is to see if an FDA-approved drug (Gralise) can help people with certain types of neuropathic pain without causing too many side effects.

Study Type

  • Study Type: Interventional
  • Study Design
    • Allocation: N/A
    • Intervention Model: Single Group Assignment
    • Primary Purpose: Treatment
    • Masking: None (Open Label)
  • Study Primary Completion Date: June 2014

Detailed Description

This research is being conducted to see if the drug Gralise can help people with Complex Regional Pain Syndrom Type I (CRPS I) without causing too many side effects. CRPS I is one of the most common conditions of neuropathic pain (pain that results from damage to nerves in the peripheral nervous system). Gralise is approved by the U.S. Food and Drug Administration (FDA) to treat postherpetic neuralgia (a complication of the disease Shingles, which is caused by the chickenpox virus), but is not approved to treat CRPS I.


  • Drug: Gabapentin

Arms, Groups and Cohorts

  • Experimental: CRPS I Pain Subjects
    • This is an open label study that involves taking Gralise pills (gastic-retentive gabapentin) for 8 weeks. Day 1-15: Titration phase- titrate Gralise from 300 mg/day to 1800 mg/day Day 16-42: Maintenance phase- maintain the dose of 1800 mg/day Day 43-56: Taper phase- taper the Gralise from 100 mg/day to 300 mg/day

Clinical Trial Outcome Measures

Primary Measures

  • Visual Analog Scale (VAS) at Visit 3
    • Time Frame: At visit 3
    • Subjects rated their pain using the VAS at visit 3, which was the last day of their maintenance phase. After this visit, subjects begin to taper the gralise. The VAS is subject reported on a scale of 0-10 with 0 being no pain and 10 being the worst pain they can imagine. Results reported are an average of the 3 subjects who completed visit 3.

Participating in This Clinical Trial

Inclusion Criteria

1. Subject will be between 18 to 80 years of age.

2. Subject has not been on Gralise.

3. Subject has not been on gabapentin for at least one month.

4. Subject agrees to make no change in his/her current pain medications during the study period to ensure that comparisons can be made before and after the Gralise treatment.

5. Subject has a VAS pain score of 5 or above at the beginning of the study.

6. Subject has had CRPS I for at least three months to avoid clinical uncertainty and minimize the study variation.

7. Female subjects of childbearing age must have a negative urine pregnancy test at the initial visit.

Exclusion Criteria

1. Subject has severe liver or renal disease that will affect the elimination of Gralise. (Renal dysfunction is defined as eGFR < 60. Hepatic dysfunction is defined as LFTs ≥ 3X ULN.)

2. Subject has pending litigation related to his/her CRPS I condition.

3. Subject is pregnant or lactating.

4. Subject is allergic to gabapentin or Gralise.

5. Subject has a positive urine (illicit) drug test.

6. Subject has any history of suicidal thoughts or behaviors, as self reported or in documented medical history.

7. Subjects with known seizure disorders (except febrile seizures) and/or taking antiepileptic drugs.

Gender Eligibility: All

Minimum Age: 18 Years

Maximum Age: 80 Years

Are Healthy Volunteers Accepted: No

Investigator Details

  • Lead Sponsor
    • Massachusetts General Hospital
  • Provider of Information About this Clinical Study
    • Principal Investigator: Jianren Mao, MD, PhD, Principal Investigator – Massachusetts General Hospital
  • Overall Official(s)
    • Jianren Mao, M.D., Ph.D., Principal Investigator, Massachusetts General Hospital

Citations Reporting on Results

Mao J. Translational pain research: achievements and challenges. J Pain. 2009 Oct;10(10):1001-11. doi: 10.1016/j.jpain.2009.06.002. Epub 2009 Jul 22. Review.

Mao J, Chen LL. Systemic lidocaine for neuropathic pain relief. Pain. 2000 Jul;87(1):7-17. Review.

Mao J, Gold MS, Backonja MM. Combination drug therapy for chronic pain: a call for more clinical studies. J Pain. 2011 Feb;12(2):157-66. doi: 10.1016/j.jpain.2010.07.006. Epub 2010 Sep 17. Review.

Sindrup SH, Jensen TS. Efficacy of pharmacological treatments of neuropathic pain: an update and effect related to mechanism of drug action. Pain. 1999 Dec;83(3):389-400. Review.

van de Vusse AC, Stomp-van den Berg SG, Kessels AH, Weber WE. Randomised controlled trial of gabapentin in Complex Regional Pain Syndrome type 1 [ISRCTN84121379]. BMC Neurol. 2004 Sep 29;4:13.

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