This study is being conducted to evaluate the safety and tolerability of treatment with CTP-499 in non-dialysis patients associated with moderate chronic kidney disease.

This study will evaluate the safety and tolerability of treatment with CTP-499 starting with 600 milligrams (mg) once a day (QD) for 2 weeks followed by 600 mg twice a day (BID) for 2 weeks in non-dialysis patients associated with moderate chronic kidney disease defined as an estimated Glomerular Filtration Rate or eGFR that is 30-59 mL/min/1.73m2

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