Phase 2 N=187 Randomized Quadruple-blind Treatment

Safety/Efficacy Study of Retigabine vs. Placebo in Post-Herpetic Neuralgia (PHN)

Postherpetic Neuralgia

Bottom Line

View on ClinicalTrials.gov: NCT00612105 ↗

Enrolled (actual)

187

Serious AEs

4.3%

Results posted

Jan 2012

Primary outcome: Primary: Primary Endpoint Will be the Change From Baseline in Average Pain Score Over the Last 7 Days of the Maintenance Phase. — -2.65; -2.22 Scores on a scale — p=0.2537

Study Design & Population

Study type: Interventional
Phase: Phase 2
Interventions: Retigabine (Drug); Placebo (Drug)
Age: Adult, Older Adult · 18+ yrs
Sex: All
Sponsor: Bausch Health Americas, Inc.
Primary completion: May 2009

Outcome Measures

Outcome	Result	p-value
PRIMARY Primary Endpoint Will be the Change From Baseline in Average Pain Score Over the Last 7 Days of the Maintenance Phase.	-2.65; -2.22	0.2537
SECONDARY Change From Baseline to Weeks 2 and 4 of the Maintenance Phase in Mean In-clinic Pain Assessment	-2.7; -2.4; -2.9; -2.4	—
SECONDARY Number of Rescue Medication Tablets Taken Per Day During the Maintenance Phase (MP)	0.92; 0.84; 0.89; 0.79; 0.74; 0.85	—
SECONDARY Change From Baseline in Pain Intensity Score at Each Week During the Maintenance Phase (MP)	-2.35; -2.08; -2.64; -2.34; -2.82; -2.43	—
SECONDARY Number of Participants Classified as Responders, With a 50% and 30% Pain Reduction From Baseline to the Last 7 Days of the Maintenance Phase	33; 22; 52; 32; 33; 22	—
SECONDARY Change From Baseline to the End of the MP (Included All Participants Who Completed Week 4 of the MP and Who Terminated Early During the MP) in Medical Outcomes Study (MOS) Sleep Scale Scores	-5.70; -6.88; -11.47; -9.43; 9.05; 5.26	—
SECONDARY Change From Baseline to the End of the MP (Included All Participants Who Completed Week 4 of the MP and Who Terminated Early During the MP) in Sleep Quantity	0.5; 0.2	—
SECONDARY Number of Participants With the Indicated Change From Baseline to the End of the Maintenance Phase in Optimal Sleep Based on the Sleep Quantity Domain of the MOS Sleep Scale	12; 8; 63; 42; 9; 7	—
SECONDARY Number of Participants With the Indicated Overall Patient Global Impression of Change (PGIC)	20; 8; 27; 15; 19; 10	—
SECONDARY Mean Score on the Treatment Satisfaction Questionnaire for Medication (TSQM) at the End of the Maintenance Phase	59.10; 49.51; 67.76; 92.11; 69.97; 74.66	—
SECONDARY Scores on the Brief Pain Inventory-Short Form (BPI-SF) at the End of the MP for All Participants Who Completed Week-4 of the MP and Who Terminated Early During the MP	3.17; 3.58; 2.00; 2.27; 58.4; 49.4	—
SECONDARY Scores on the Medical Outcomes Short Form-36 (SF-36) at the End of the MP for All Participants Who Completed Week 4 of the MP and Who Terminated Early During the MP	51.12; 50.47; 43.82; 45.54; 43.22; 43.30	—
SECONDARY Scores for Reported Health Transition at the End of the MP for All Participants Who Completed Week 4 of the MP and Who Terminated Early During the MP	2.68; 2.37	—
SECONDARY Number of Participants With the Indicated Responses at Baseline to the Question: "How Painful Was the Affected Side Compared to the Opposite Side?" in an Assessment of Tactile Allodynia	89; 40; 19; 14; 16; 7	—
SECONDARY Number of Participants With the Indicated Responses at Baseline to the Questions of "Is it Cool?" and "Is it Painful?" in an Assessment of Cold Threshold and Allodynia	19; 9; 105; 52; 67; 34	—
SECONDARY Number of Subjects With the Indicated Responses at Baseline to the Questions: "How Sharp Was the Affected Side Compared to the Opposite Side?" and "How Painfule Was the Affected Side Compared to the Opposite Side?" in an Assessment of Hyperalgesia	66; 32; 7; 10; 51; 19	—
SECONDARY Number of Participants With the Indicated Responses at the End of the MP to the Question: "How Painful Was the Affected Side Compared to the Opposite Side?" in an Assessment of Tactile Allodynia	30; 29; 44; 20; 10; 8	—
SECONDARY Number of Participants With the Indicated Responses at the End of the MP to the Questions of "Is it Cool?" and "Is it Painful?" in an Assessment of Cold Threshold and Allodynia	14; 7; 70; 50; 63; 44	—
SECONDARY Number of Participants With Indicated Responses at the End of the MP to the Questions: "How Sharp Was the Affected Side Compared to the Opposite Side?" and "How Painful Was the Affected Side Compared to the Opposite Side?" in an Assessment of Hyperalgesia	29; 24; 24; 19; 31; 14	—
SECONDARY Change From Baseline in the Average Diary Pain Score to the Last 7 Days of the Maintenance Phase by Post Herpetic Neuralgia (PHN) Subtype "Irritable Nociceptors"	-1.78; -2.85	—
SECONDARY Change From Baseline in the Average Diary Pain Score to the Last 7 Days of the Maintenance Phase by Post Herpetic Neuralgia (PHN) Subtype"Deafferentation Type 1 (D Type 1)"	-3.57; -5.29	—
SECONDARY Change From Baseline in the Average Diary Pain Score to the Last 7 Days of the Maintenance Phase by Post Herpetic Neuralgia (PHN) Subtype "Deafferentation Type 2 (D Type 2)"	-4.14; 0.00	—
SECONDARY Change From Baseline in the Average Diary Pain Score to the Last 7 Days of the Maintenance Phase by Post Herpetic Neuralgia (PHN) Subtype "Unclassifiable"	-2.69; -1.87	—

Summary

The purpose of the study is to evaluate the efficacy of retigabine vs. placebo in reducing pain associated with post-herpetic neuralgia.

Eligibility Criteria

Inclusion Criteria

Ability to provide informed consent
Male or female subjects
18-85 years of age
PHN for more than 6 months after the healing of herpes zoster skin rash
Has a pain score at screening and randomization that qualifies

Exclusion Criteria

Other significant pain that may potentially confound PHN pain assessment
Previous neurolytic or neurosurgical therapy for PHN
Subject has evidence of a progressive central nervous system (CNS) disease (e.g. CNS lupus, tumors, multiple sclerosis, Alzheimer's), lesion, or encephalopathy
Significant psychiatric or neuropsychiatric disorders including but not limited to severe depression, bipolar disorder or schizophrenia spectrum disorder, history of suicide attempt, or recent history of suicidal ideation
Has clinically significant abnormalities on physical examination, vital signs, ECG, or laboratory tests at the screening visit

View full record on ClinicalTrials.gov →

Data sourced from ClinicalTrials.gov (NCT00612105). Outcome figures and adverse-event rates are extracted automatically from the registry's posted results and are provided for clinician reference, not as a substitute for the primary publication.