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

Study Overview
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Brief Summary
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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.

Detailed Description
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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.

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

Conditions
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Complex Regional Pain Syndrome I (CRPS I)

Intervention / Treatment
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* Drug: Gabapentin


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Subject will be between 18 to 80 years of age. Subject has not been on Gralise. Subject has not been on gabapentin for at least one month. 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. Subject has a VAS pain score of 5 or above at the beginning of the study. Subject has had CRPS I for at least three months to avoid clinical uncertainty and minimize the study variation. Female subjects of childbearing age must have a negative urine pregnancy test at the initial visit. Exclusion Criteria: 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.) Subject has pending litigation related to his/her CRPS I condition. Subject is pregnant or lactating. Subject is allergic to gabapentin or Gralise. Subject has a positive urine (illicit) drug test. Subject has any history of suicidal thoughts or behaviors, as self reported or in documented medical history. Subjects with known seizure disorders (except febrile seizures) and/or taking antiepileptic drugs.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: CRPS I Pain Subjects<br>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 | Drug: Gabapentin<br> <br> * Other names: Gralise;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Visual Analog Scale (VAS) 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. | At visit 3 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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CRPS I