A Study to Evaluate the Safety and Efficacy of CR845 in Chronic Kidney Disease Patients With Moderate-to-Severe Pruritus

This study will consist of a Screening Period, a 7-day Run-in Period, a 12 week Treatment Period, and a Follow-up Visit (approximately 7 to 10 days after the last dose of study drug). Informed consent will be obtained prior to performing any study-specific procedures. Screening will occur within 7 to 28 days prior to randomization to assess eligibility. If patients continue to meet all inclusion and no exclusion criteria at the end of the 7-day Run-in Period, they will be randomized in a 1:1:1:1 ratio to receive orally once daily either placebo or CR845 tablets at doses of 0.25, 0.5 or 1 mg. Randomization will be stratified according to the patient's renal disease status: moderate CKD; severe CKD non-dialysis; severe CKD on dialysis (ie, 3 categories). A final safety Follow-up Visit will be conducted 7 to 10 days after the last dose of study drug.