Safety & Tolerability Study of CTP-499 in Patients With Moderate Chronic Kidney Disease

Inclusion Criteria: * Patient has a diagnosis of chronic kidney disease * If taking antihypertensive and antidiabetes medications, regimen must be stable for a minimum of 4 weeks * Patient has systolic blood pressure less than or equal to 160 mm Hg and diastolic blood pressure less than or equal to 95 mm Hg Exclusion Criteria: * Patient has concurrent condition such as uncontrolled inflammatory disease, acute infection or clinically unstable autoimmune, endocrine, neurological, psychiatric, retinal, cardiovascular, bronchopulmonary, hepatic, gastrointestinal or musculoskeletal disorder * Patient has acute, active and/or current unstable renal impairment disease * Patient has been hospitalized for acute renal failure in the past year * Patient has active malignancy or a history of neoplastic disease * Patient has QTc interval \> 450 milliseconds * Patient is currently on cytotoxic or other immunosuppressive therapy