A Study to Evaluate the Safety and Efficacy of Difelikefalin in Advanced Chronic Kidney Disease Patients With Moderate-to-Severe Pruritus

Inclusion Criteria: To be eligible for inclusion into the study, a patient must meet the following criteria:

• Advanced stage 4 and 5 CKD and end stage renal disease on hemodialysis
• Subject self-reports experiencing at least near-daily (eg, most days of a week)pruritus for at least 6 months prior to screening.
• Inadequate response to current or prior treatments (including emollients/moisturizers,topical medications, or systemic treatments) for pruritus prior to screening. Prior to randomization on Day 1 of Treatment Period 1:

1. Has recorded at least 4 WI-NRS scores during the 7-day Run-in Period; and
2. Has a mean baseline WI-NRS score ≥ 5, defined as the average of all non-missing scoresreported during the 7-day Run-in Period.

Exclusion Criteria: A patient will be excluded from the study if any of the following criteria are met:

• Scheduled to receive a renal replacement therapy (dialysis or kidney transplant)during the study.
• Has a concomitant disease, significant medical condition orphysical/laboratory/ECG/vital signs abnormality that, in the opinion of theinvestigator, puts the subject at undue risk or interferes with interpretation ofstudy results, impedes completion of the study procedures, or compromises the validityof the study measurements.
• New or change of treatment received for itch, including antihistamines andcorticosteroids (oral, intravenous, or topical), within 14 days prior to the start ofrun-in.