This is a multicenter, open-label study to evaluate the safety and effectiveness of intravenous (IV) CR845 at a dose of 0.5 mcg/kg administered after each dialysis session. The study includes an up to 12-week Treatment Period.

Screening Period: The Screening Period includes a Screening Visit and a Run-In Period. Informed consent will be obtained prior to performing any study-specific procedures. The Screening Visit will occur within 21 days prior to the start of the Run-in Period. Patients will start the Run-in Period during the week prior to Treatment Period to complete eligibility verification.

Treatment Period: All scheduled study visits during the Treatment Period will be conducted on dialysis days. Patients will be administered CR845 as an IV bolus after the end of their dialysis during a Treatment Period of up to 12 weeks so that each patient will receive CR845 3 times weekly for a total of up to 36 doses. End of treatment (EOT) is defined as the first day of dialysis following the last dose of drug. The EOT procedures will be conducted on the dialysis visit following the last dose of study drug.

Follow-up Visit: A final safety Follow up Visit will be conducted 7-10 days after the EOT/Early Termination Visit.

Key Inclusion Criteria:

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

• Has end-stage renal disease (ESRD) and has been on hemodialysis 3 times per week for at least 3 months prior to the start of screening;

• Has at least 2 single-pool Kt/V measurements ≥1.2, or at least 2 urea reduction ratio measurements ≥65%, or 1 single pool Kt/V measurement ≥1.2 and 1 urea reduction ratio measurement ≥65% on different dialysis days during the 3 months period prior to screening;

• Prior to Treatment:

  • Has completed at least 3 Worst Itching Intensity NRS questionnaires from the start of the Run-in Period up to and including the pre-dose assessment on Day 1;

Key Exclusion Criteria:

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

• Known noncompliance with dialysis treatment that in the opinion of the investigator would impede completion or validity of the study;
• Scheduled to receive a kidney transplant during the study;
• New or change of treatment received for itch including antihistamines and corticosteroids (oral, IV, or topical) within 14 days prior to screening;
• New or change of prescription for opioids, gabapentin, or pregabalin within 14 days prior to screening;
• Received another investigational drug within 30 days or five half-lives (whichever is longer) prior to the start of dosing or is planning to participate in another interventional clinical study while enrolled in this study;
• Has pruritus only during the dialysis session (by patient report);
• Is receiving ongoing ultraviolet B treatment and/or anticipates receiving such treatment during the study;
• Participated in a previous clinical study with CR845.