Treatment of Chronic Itch in Patients Under Arsenic Exposure With Naloxone

Phase 1

Completed

• Conditions: Chronic Pruritus
• Interventions: Drug: Naloxone; Drug: Placebo

• Registration Number: NCT03751111
• Lead Sponsor: Xiangya Hospital of Central South University

Brief Summary

The purpose of this study is to assess the efficacy and safety of sublingual naloxone in the treatment of chronic itch in patients under arsenic exposure.

Detailed Description

This study aims to determine the efficacy and safety of sublingual naloxone in the treatment of chronic, refractory itch in patients under long-term arsenic exposure. In this study, 120 subjects with a moderate-to-severe symptom of itching (numeric rating scale, NRS≥3) will be recruited and randomly treated with either sublingual naloxone (60 subjects) or placebo (60 subjects). The severity of itching will be evaluated in the wash out phase, baseline, and one week after the treatment through reporting of subjective symptomatology (itch NRS) via the interview. Quality of sleep measured by the Pittsburgh Sleep Quality Index (PSQI) and Dermatology Life Quality Index (DLQI) will serve as the secondary outcome.

Study Timeline

• Study First Submitted: 2018-11-21
• Study First Submitted QC: 2018-11-21
• Study First Posted: 2018-11-23
• Study Start: 2019-02-13
• Primary Completion: 2019-03-01
• Study Completion: 2019-03-30
• Results First Submitted: 2023-01-23
• Status Verified: 2025-04
• Results First Submitted QC: 2025-04-02
• Last Update Submitted: 2025-04-02
• Results First Posted: 2025-04-20
• Last Update Posted: 2025-04-20

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 126

Inclusion Criteria

1. Aged 18 years or over and without diseases except arsenic-related pruritus
2. Ability to study protocol and to give informed consent by himself/herself voluntarily
3. The number of male or female subjects is required more than 1/3 of the total number of subjects
4. Numeric Rating Sscale≥3 at the baseline
5. Subjects taking hormone-containing medications must be on a stable dose for 6 months prior to study start to avoid any confounding influence on sensory and pain perception

Exclusion Criteria

1. Use of oral anti-inflammatory medications for 2 weeks prior to the study start.
2. Use of oral anti-histamines for 2 weeks prior to the study start.
3. Use of topical or oral anti-pruritic agents for 2 weeks prior to the study start.
4. Use of oral neuromodulatory agents for 2 months prior to study start.
5. Current use of chronic pain medications (including opioids, antidepressants and anti-epileptic drugs).
6. Use of nicotine-containing products for the past 6 months prior to study start.
7. History of basic itchy dermatological diseases before such as eczema wich may influence the judgement of drug efficacy.
8. Unstable thyroid function within the past 6 months prior to study start to exclude thyroid-related neuropathy.
9. Known history of central or peripheral nervous system dysfunction.
10. History of acute hepatitis, chronic liver disease or end stage liver disease.
11. History of human immunodeficiency virus (HIV) or acquired immune deficiency syndrome.
12. History of neuropathy associated with chronic obstructive pulmonary disease, diabetes mellitus, documented exposure to organophosphates or heavy metals or polychlorinated biphenyls.
13. Known nutritional deficiency (vitamin B12, vitamin D, iron or zinc) within 3 months prior to the study start.
14. Use of illicit drugs within the past 6 months prior to study start.
15. Lyme disease, porphyria, rheumatoid arthritis, Hansen's disease (leprosy) or use of antineoplastic chemotherapeutic agents.
16. Patients considered by researchers that are not suitable to the study.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Naloxone	Naloxone	Naloxone at an sublingual dose of 0.4 mg daily will be given to each subject.
Placebo	Placebo	Sublingual placebo will be given to each subject.

Primary Outcome Measures

Name	Time	Method
Numeric Rating Scale for Itch	1 week	Participants will be invited to report the severity of itch using the Numeric Rating Scale (NRS) for Itch at the baseline and week 1 of the trial. Numeric Rating Scale (NRS) for Itch is a self-reported scale to measure the intensity of itch, with a range of score from 0 to 10. Higher scores indicate stronger itching, with a score of 1 or 2 suggesting mild itching, a score between 3 and 6 suggesting moderate itching, and a greater than 7 indicating severe itching.

Secondary Outcome Measures

Name	Time	Method
Pittsburgh Sleep Quality Index (PSQI)	1 week	Measured by the Pittsburgh Sleep Quality Index (PSQI) at baseline and week 1 of the trial. Each component score of the PSQI ranges from 0 to 3, with 3 indicating the greatest dysfunction or disturbance. The seven component scores are then summed to obtain a global PSQI score, which ranges from 0 to 21. Higher scores indicate poorer sleep quality, with a score greater than 5 suggesting significant sleep difficulties.
Serological Indicator	1 week	Level of serum beta-endorphin will be tested at baseline and week 1 of the trial
Dermatology Life Quality Index (DLQI)	1 week	Dermatology Life Quality Index (DLQI) at baseline and week 1 of the trial. It consists of ten questions which ask about symptoms, feelings, daily activities, leisure, work, school, personal relationships, and treatment. Every question asked relates to the previous week. The user can tick a box in either: 'not at all', 'a little', 'a lot' or 'very much'. Questions are scored from 0 to 3 and totalled, giving an overall score out of 30. The final score ranges from 0 (no impact on quality of life) to 30 (maximum impairment).

Trial Locations

Locations (1)

Xiangya Hospital; 🇨🇳 Changsha, Hunan, China