This is a randomized, open-label, multi-center clinical study aimed at evaluating the efficacy and safety of 12 weeks of nalfurafine hydrochloride administration in the treatment of pruritus in patients undergoing maintenance hemodialysis.

Inclusion Criteria:

• Age range of 18-80 years old (including both ends), male or female not limited.
• Chronic renal failure patients who undergo stable dialysis for 3 months or more, receive regular hemodialysis 3 times a week, and are expected to have no significant changes in treatment or rapid changes in their condition during the clinical trial period.
• Within one year prior to signing the informed consent form, the effectiveness of itch treatment (including topical medications such as moisturizers/moisturizers, systemic medications such as antihistamines or antiepileptic drugs, and non pharmacological treatments) was not satisfactory.
• Those who are able to understand and comply with the research procedures and methods, voluntarily participate in this study, and sign a written informed consent form.
• The number of days during which VAS values are measured at both wake-up and bedtime in the baseline period must be no less than 5 days, and the average value of the larger VAS values in morning and evening measurements must not be less than 50 mm.
• The number of days evaluated for the severity of itching in Xie Chuandao during the baseline period must be no less than 5 days at both wake-up and bedtime.

Exclusion Criteria:

• Given poor compliance with dialysis treatment, researchers believe that it may affect the effectiveness and safety of clinical studies.
• Patients who plan to undergo kidney transplantation or other elective surgeries during the study period.
• Patients with alanine aminotransferase (ALT), aspartate aminotransferase (AST), or glutamine transferase (GGT) levels exceeding the upper limit of normal (ULN) by 2 times, or total bilirubin levels exceeding the upper limit of normal (ULN) by 2 times during the screening period.
• Skin itching is not caused by chronic kidney disease, including allergic skin diseases (atopic dermatitis, urticaria, eczema, drug rash, etc.), physical skin diseases (prickly heat, solar rash, etc.), infectious skin diseases (insect bite dermatitis, chickenpox, measles, pyoderma, tinea corporis, etc.), cholestatic liver disease, etc.
• Severe cardiovascular disease patients: those who have been screened for NYHA class III or IV, acute myocardial infarction, unstable angina, large pericardial effusion, severe arrhythmia, or abnormal electrocardiogram within the previous 6 months and are deemed unsuitable for inclusion by the researchers.
• Screening for individuals who have been in the active stage of malignant tumors within the previous 12 months, or have received radiotherapy, chemotherapy, targeted therapy, and immunotherapy during this period.
• There are uncontrollable or drug-induced fungal, bacterial, viral, or other infections, including tuberculosis patients undergoing anti tuberculosis treatment, patients known to be infected with human immunodeficiency virus (HIV), etc.
• Hypertensive patients who cannot achieve good control with drug therapy: systolic blood pressure ≥ 180mmHg, or diastolic blood pressure ≥ 110mmHg.
• Patients who are currently using glucocorticoids and immunosuppressants.
• Patients with mental illness or cognitive impairment who are unable to correctly understand VAS scores and describe their own feelings.
• Received or adjusted antihistamines, systemic or local corticosteroids (excluding ear or eye preparations), calcineurin inhibitors, gabapentin, pregabalin, and other restricted combination drugs within 7 days prior to screening, or expected to change their treatment regimen during the study period.
• Started receiving or adjusting drugs that may affect the assessment of itch relief efficacy within 2 weeks prior to screening, including but not limited to antipsychotics, sedatives, selective serotonin reuptake inhibitors (SSRIs), anxiolytics, or tricyclic antidepressants, or expected to change their treatment regimen during the study period.
• Individuals with a history of drug abuse, drug dependence, or alcohol abuse within the past 12 months prior to screening.
• Select patients who have received phototherapy for pruritus within the previous month.
• Individuals who have used opioid receptor agonists or antagonists within the past 2 weeks prior to screening.
• Individuals with a known history of allergy to opioid drugs, or those who are allergic to test drug excipients.
• Individuals who have participated in other clinical studies and used the investigational drug or medical device within the 28 days prior to screening, or whose investigational drug is within 5 half lives prior to screening.
• Pregnant women, breastfeeding women, patients with positive pregnancy tests, or those who do not agree to use contraception during the study period.
• Other patients deemed unsuitable by researchers to participate in this clinical study.