A Study In Patients With Neuropathic Pain From Post-Herpetic Neuralgia (PHN)
Trial overview
Change from baseline in the mean 24-hour average pain intensity (API) score at the end of maintenance treatment (EOMT) using Last Observation Carried Forward (LOCF) data
Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)
Change from baseline in the mean night-time average pain intensity (API) score at EOMT using LOCF data
Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)
Change from baseline in the mean current morning pain intensity score at EOMT using LOCF data
Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)
Change from baseline in the mean night-time worst pain intensity score at EOMT using LOCF data
Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)
Change from baseline in the mean sleep interference score at EOMT using LOCF data
Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)
Change from baseline in the mean day-time average pain intensity(API) score at EOMT using LOCF data
Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)
Change from baseline in the mean current evening pain intensity score at EOMT using LOCF data
Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)
Change from baseline in the mean day-time worst pain intensity score at EOMT using LOCF data
Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)
Change from baseline in pain quality as assessed by the Neuropathic Pain scale (NPS) summary scores at EOMT using LOCF data
Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)
Change from baseline in pain characteristics and intensity as assessed by the Short Form-McGill Pain Questionnaire (SF-MPQ) at EOMT using LOCF data
Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)
Change from baseline in dynamic allodynia at EOMT using LOCF data
Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)
Number of participants who are responders on the Patient Global Impression of Change (PGIC) questionnaire at EOMT using LOCF data
Timeframe: EOMT (representing the earliest date of Week 13 visit/withdrawal visit)
Number of participants achieving various levels of percent reduction from baseline in the mean 24-hour average pain intensity score at EOMT using LOCF data
Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)
Time to onset of sustained improvement in the 24-hour average pain intensity score
Timeframe: Anytime post-baseline until date of last dose of study medication (up to Week 13)
Change from baseline in the mean daily dose in milligrams of rescue medication at EOMT using LOCF data
Timeframe: Baseline and EOMT (Week 13 or early withdrawal)
Change from baseline in severity of pain and the impact of pain as assessed by the Brief Pain Inventory (BPI) at EOMT using LOCF data
Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)
Change from baseline in quality of life as assessed by the SF-36 at EOMT using LOCF data
Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)
Number of participants who are responders on the Clinician Global Impression of Change (CGIC) questionnaire at EOMT using LOCF data
Timeframe: EOMT (representing the earliest date of Week 13 visit/withdrawal visit)
Change from baseline in emotional functioning as assessed by the POMS-B at EOMT using LOCF data
Timeframe: Baseline and EOMT (representing the earliest date of Week 13 visit/withdrawal visit)
Participation criteria
- 18 years or older
- Female subjects are eligible if of non-childbearing potential or not lactating, has a negative pregnancy, and agrees to use one a specified highly effective method for avoiding pregnancy
- Other chronic pain conditions not associated with PHN. However, the subject will not be excluded if:
- The pain is located at a different region of the body; and
- 18 years or older
- Female subjects are eligible if of non-childbearing potential or not lactating, has a negative pregnancy, and agrees to use one a specified highly effective method for avoiding pregnancy
- Documented medical diagnosis of PHN of with pain present for at least three months from the healing of a herpes zoster rash
- Baseline 24-hour average pain intensity score ≥ 4.0 based on an 11-point PI-NRS
- Provides written informed consent in accordance with all applicable regulatory requirements
- Other chronic pain conditions not associated with PHN. However, the subject will not be excluded if:
- The pain is located at a different region of the body; and
- The pain intensity is not greater than the pain intensity of the PHN; and
- The subject can assess PHN pain independently of other pain
- Is unable to discontinue prohibited medications or non-drug therapies or procedures throughout the duration of the study
- Hepatic impairment defined as ALT or AST > 2x upper limit of normal (ULN), or alkaline phosphatase or bilirubin > 1.5x ULN
- Chronic hepatitis B or C
- Impaired renal function defined as creatinine clearance <60 mL/min or requiring hemodialysis
- Corrected QT (QTc) interval ≥ 450 msec or QTc interval ≥480 msec for patients with Bundle Branch Block
- Uncontrolled hypertension at screen (sitting systolic >160 mmHg and/or sitting diastolic >90 mmHg)
- Current diagnosis of active epilepsy or any active seizure disorder requiring chronic therapy with antiepileptic drugs
- Medical condition or disorder that would interfere with the action, absorption, distribution, metabolism, or excretion of GEn, or, in the investigator's judgment
- Is considered to be clinically significant and may pose a safety concern, or,
- Could interfere with the accurate assessment of safety or efficacy, or,
- Could potentially affect a subject's safety or study outcome
- Meets criteria defined by the DSM-IV-TR for a major depressive episode or for active significant psychiatric disorders within last year
- Depression in remission, with or without antidepressant treatment, may participate, unless stable antidepressant regimen is a prohibited medication
- Antidepressant medication may not be changed or discontinued to meet entry criteria and must be stable for at least three months prior to enrollment
- History of clinically significant drug or alcohol abuse (DSM‑IV‑TR) or is unable to refrain from substance abuse throughout the study. Benzodiazepines or atypical benzodiazepines as hypnotic sleep agents permitted.
- Currently participating in another clinical study in which the subject is, or will be exposed to an investigational or non-investigational drug or device
- Has participated in a clinical study and was exposed to investigational or non‑investigational drug or device:
- Within preceding month for studies unrelated to PHN, or
- Within preceding six months for studies related to PHN
- Treated previously with GEn
- History of allergic or medically significant adverse reaction to investigational products (including gabapentin) or their excipients, acetaminophen or related compounds
Trial location(s)
No location data available.
Study documents
If you wish to request for full study report, please contact - [email protected]
Results overview
Refer to study documents
Plain language summaries
Plain language summaries of clinical trial results for Phase 2-4 clinical trials that were initiated on or after January 2022 will be posted by GSK within one year following study completion.