Key Inclusion Criteria:
* A diagnosis of CKD confirmed at screening, KDOQI CKD stage 3, 4, or 5 defined by estimated Glomerular Filtration Rate (eGFR) using the CKD Epidemiology Collaboration (EPI) formula.
* Not on dialysis and no clinical evidence of impending need to initiate dialysis during the study treatment.
* Prior ESA and hypoxia-inducible factor-prolyl hydroxylase inhibitor (HIF-PHI) treatment
1. ESA/HIF-PHI-naïve: Defined as no use of any ESA/HIF-PHI treatment for at least 12 weeks before randomization; Mean of the two most recent Hb values during the screening period obtained at least 7 days apart must be ≥7.5 g/dL and \<10.0 g/dL with a difference of ≤1.3 g/dL between the two values;
2. ESA-treated: Defined as having received an approved ESA, administered intravenously or subcutaneously, for at least 6 weeks prior to randomization, with no change in ESA product and no treatment interruption exceeding 2 consecutive weeks; Mean of the two most recent Hb values during the screening period obtained at least 7 days apart must be 9.0-12.0 g/dL inclusive.
* Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) \<3× upper limit of normal (ULN)
* Transferrin saturation (TSAT) ≥20% or ferritin ≥100 ng/mL at screening test
* Serum folate and vitamin B12 ≥ lower limit of normal (LLN) at screening test
Key Exclusion Criteria:
* Concurrent retinal neovascular lesions requiring treatment.
* Chronic inflammatory disease other than glomerulonephritis that could impact erythropoiesis or concurrent autoimmune disease with inflammatory symptoms.
* History of gastric/intestinal resection considered to affect the absorption of drugs in the gastrointestinal tract or concurrent symptomatic gastroparesis despite being on treatment.
* Uncontrolled hypertension, defined as patients with hypertension having more than one of three systolic blood pressure \>180 mmHg, or diastolic blood pressure \>110 mmHg during the screening assessment
* Concurrent congestive heart failure (New York Heart Association \[NYHA\] Class III or higher).
* History of stroke, transient ischemic attack (TIA), myocardial infarction, thromboembolic event (deep vein thrombosis, DVT), pulmonary embolism, or lung infarction within 24 weeks before the screening assessment.
* Participants with a history of significant liver disease or active liver disease.
* History of a seizure disorder or any occurrence of seizures in the past.
* Serum albumin (ALB) \< 2.5 g/dL at screening test.
* Prior ESA/HIF-PHI treatment caused total bilirubin \>1.5xULN, or AST/ALT/ALP\>3xULN, or serious liver disease (acute or active chronic hepatitis, cirrhosis, etc.).
* Any prior functioning organ transplant or a scheduled organ transplantation, or anephric.
