Study of NGX-1998 for the Treatment of Postherpetic Neuralgia

Pain Clinical Trial

Official title:

A Multicenter Randomized, Double-Blind, Controlled Study to Evaluate Safety, Tolerability and Preliminary Efficacy of Two Capsaicin Concentration Variations of NGX-1998 (10% or 20% w/w) in Subjects With Postherpetic Neuralgia (PHN)

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01228838
• Other study ID #: C204
• Status: Completed
• Phase: Phase 2
• First received: October 25, 2010
• Last updated: September 6, 2012
• Start date: October 2010
• Est. completion date: September 2011

Study information

• Verified date: May 2011
• Source: NeurogesX
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Food and Drug Administration
• Study type: Interventional

Clinical Trial Summary

The purpose of this study is to assess the efficacy, safety and tolerability of NGX-1998 applied for 5 minutes for the treatment of postherpetic neuralgia (PHN).

Description:

This study is a 12-week multicenter randomized, double-blind, controlled evaluation of the efficacy, safety and tolerability of NGX-1998 for the treatment of postherpetic neuralgia (PHN). Eligible subjects will have pain from PHN, with average numeric pain rating scale (NPRS) scores during screening of 4 to 9 (inclusive). Painful areas of up to 1500 cm2 will be treated during a single Test Article application. Subjects will be randomly assigned to receive NGX-1998 (10% or 20% w/w) or placebo according to an unequal allocation scheme of 2:2:1. Subjects will also be stratified by gender.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 183
• Est. completion date: September 2011
• Est. primary completion date: September 2011
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 18 Years to 90 Years

Eligibility

Inclusion Criteria:

• Between 18 and 90 years of age, inclusive.

• Diagnosis of PHN with at least six (6) months of pain since shingles vesicle crusting.

• Average NPRS scores for PHN-associated pain during Days -14 to -4 of 4 to 9, inclusive.

• Intact, unbroken skin over the painful area(s) to be treated.

• If taking chronic pain medications, be on a stable (not PRN) regimen for at least 21 days prior to Test Article Application Visit and willing to maintain medications at same stable dose(s) and schedule throughout the study.

• Female subjects with child-bearing potential must have a negative serum beta human chorionic gonadotropin (hCG) pregnancy test, to be performed within 7 days of the Test Article Application Visit.

• All subjects must be willing to use effective methods of birth control and/or refrain from participating in a conception process during the study.

• If breastfeeding, the subject should agree not to breastfeed their child after treatment on the treatment day.

• Be willing and able to comply with protocol requirements for the duration of study participation.

• Subjects must sign an informed consent form for this study approved by the Investigator's Institutional Review Board/Independent Ethics Committee (IRB/IEC).

Exclusion Criteria:

• Concomitant opioid medication, unless orally or transdermally administered and not exceeding a total daily dose of morphine 60 mg/day, or equivalent. Parenteral opioid use is excluded.

• Unavailability of an effective medication for treatment related discomfort for the subject, such as unwillingness to use opioid analgesics during study treatment, or high tolerance to opioids precluding the ability to relieve treatment-associated discomfort.

• Active substance abuse or history of chronic substance abuse within the past year, or prior chronic substance abuse judged likely to recur during the study period.

• Recent use (within 21 days preceding the Test Article Application Visit [Day 0]) of any topically applied pain medication on the painful areas.

• Receipt of Qutenza® within 12 months of the Test Article Application Visit (Day 0). Subjects who have received Qutenza® 12 months or more before Test Article Application Visit (Day 0), and who did not respond should also be excluded.

• Participation in another drug research study within 30 days preceding the Test Article Application Visit (Day 0).

• Current use of any Class I anti-arrhythmic drugs or III anti-arrhythmic drugs.

• Diabetes mellitus, unless well-controlled as evidenced by an HBA1c level less than or equal to nine percent (9%).

• A recent history of cardiovascular or cerebrovascular events or unstable hypertension, unless adequately controlled by medication.

• Significant pain of an etiology other than PHN, for example, compression-related neuropathies, fibromyalgia or arthritis.

• Painful PHN areas located on the face, above the hairline of the scalp, and/or in proximity to mucous membranes.

• Any implanted medical device for the treatment of neuropathic pain.

• History of hypersensitivity to capsaicin, local anesthetics or any components of the CTLs, Cleansing Gel or the lidocaine (2.5%) / prilocaine (2.5%) topical anesthetic cream.

• Patients with glucose-6 phosphate dehydrogenase deficiencies.

• Significant ongoing or untreated abnormalities or conditions, including active malignancy defined as treatment required in the last five (5) years, that in the opinion of the Investigator would interfere with the ability to complete the study or the evaluation of AEs.

• Patients with congenital or idiopathic methemoglobinemia.

• Recent history of a significant medical-surgical intervention in the judgment of the Investigator; examples include but are not limited to major surgery or percutaneous angioplasty/coronary artery stent placement within the past 3 months, and receipt of immunosuppressive therapy within 3 months, prior to the Test Article Application Visit [Day 0].

• Evidence of cognitive impairment including dementia that may interfere with subject's ability to complete daily pain diaries requiring subject's recall of average PHN pain level in the past 24 hours.

Study Design

Allocation: Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Caregiver, Investigator), Primary Purpose: Treatment

Related Conditions & MeSH terms

• Neuralgia
• Neuralgia, Postherpetic
• Pain
• Postherpetic Neuralgia

Intervention

Drug:
• NGX-1998
Capsaicin topical liquid to be applied for 5 minutes one time only.
• Placebo Liquid
Placebo topical liquid to be applied for 5 minutes one time only.

Locations

Country	Name	City	State
United States	NeurogesX Investigational Site	Albany	New York
United States	NeurogesX Investigational Site	Altoona	Pennsylvania
United States	NeurogesX Investigational Site	Ann Arbor	Michigan
United States	NeurogesX Investigational Site	Bloomington	Illinois
United States	NeurogesX Investigational Site	Boise	Idaho
United States	NeurogesX Investigational Site	Hattiesburg	Mississippi
United States	NeurogesX Investigational Site	Hickory	North Carolina
United States	NeurogesX Investigational Site	Huntsville	Alabama
United States	NeurogesX Investigational Site	Hyannis	Massachusetts
United States	NeurogesX Investigational Site	Irvine	California
United States	NeurogesX Investigational Site	Kansas City	Kansas
United States	NeurogesX Investigational Site	La Jolla	California
United States	NeurogesX Investigational Site	Lexington	Kentucky
United States	NeurogesX Investigational Site	Madison	Wisconsin
United States	NeurogesX Investigational Site	Marietta	Georgia
United States	NeurogesX Investigational Site	Minneapolis	Minnesota
United States	NeurogesX Investigational Site	Napa	California
United States	NeurogesX Investigational Site	New Port Richey	Florida
United States	NeurogesX Investigational Site	North Palm Beach	Florida
United States	NeurogesX Investigational Site	Portland	Oregon
United States	NeurogesX Investigational Site	Richmond	Virginia
United States	NeurogesX Investigational Site	Rochester	New York
United States	NeurogesX Investigational Site	Salt Lake City	Utah
United States	NeurogesX Investigational Site	San Antonio	Texas
United States	NeurogesX Investigational Site	San Francisco	California
United States	NeurogesX Investigational Site	Santa Monica	California
United States	NeurogesX Investigational Site	Sarasota	Florida
United States	NeurogesX Investigational Site	Seattle	Washington
United States	NeurogesX Investigational Site	Shreveport	Louisiana
United States	NeurogesX Investigational Site	St. Petersburg	Florida
United States	NeurogesX Investigational Site	Tucson	Arizona
United States	NeurogesX Investigational Site	Webster	Texas
United States	NeurogesX Investigational Site	Wenatchee	Washington
United States	NeurogesX Investigational Site	West Des Moines	Iowa
United States	NeurogesX Investigational Site	Winston-Salem	North Carolina

Sponsors (1)

Lead Sponsor	Collaborator
NeurogesX

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Percent change from baseline in the "average pain for the past 24 hours" NPRS score during Weeks 2-8.		Weeks 2-8	Yes
Secondary	Absolute change and percent change from baseline in the "average pain for the past 24 hours" NPRS score at Week 8 and 12		Week 8 and Week 12	Yes
Secondary	Absolute change and percent change from baseline in the "average pain for the past 24 hours" NPRS score during Weeks 2-12.		Weeks 2-12	Yes
Secondary	Proportion of subjects with at least a 30% decrease from baseline in their "average pain for the past 24 hours" NPRS during Weeks 2-8, Weeks 2-12, at Week 8 and Week 12.		Weeks 2-12	Yes
Secondary	Proportion of subjects with at least a 2 unit decrease from baseline in their "average pain for the past 24 hours" NPRS during Weeks 2-8, Weeks 2-12, at Week 8 and Week 12.		Week 8 and Week 12	Yes