a study in patients with neuropathic pain from post-herpetic neuralgia (phn)

Conditions: Neuralgia, Postherpetic

Summary: the purpose of this study is to determine whether gabapentin enacarbil (xp13512/gsk1838262), hereafter referred to as gen is effective in the treatment of neuropathic pain associated with post-herpetic neuralgia (phn).

the primary purpose of study pxn110748 was to evaluate efficacy and safety of 3 fixed doses of gen in the treatment of phn.

Eligibility criteria:
inclusion 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 * 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 exclusion criteria: * 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

Keywords: neuropathic pain post-herpetic neuralgia phn