Pharmacokinetics and Safety Pilot Study of Single-Dose Oral and Intravenous CTAP101 in Stage 3 and 4 Chronic Kidney Disease Subjects

Inclusion Criteria: * Body mass index between great than or equal to 18 and less than or equal to 40 kg/m2 * Plasma iPTH value for Stage 3 CKD greater than or equal to 70 pg/mL and lower than or equal to 1000 pg/mL * Plasma iPTH value for Stage 4 CKD greater than or equal to 110 pg/mL and lower than or equal to 1000 pg/mL * Adjusted serum total calcium value greater than 8.4 mg/dL and lower than 10.0 mg/dL * Serum phosphorus value greater than or equal to 2.5 mg/dL and lower than or equal to 5.5 mg/dL * Serum 25-hydroxyvitamin D level greater than 15 ng/mL and lower than 30 ng/mL * Hemoglobin level greater than or equal to 10 g/dL Exclusion Criteria: * Has nephrotic range proteinuria * Has liver disease or significant hepatic dysfunction * Is taking Cytochrome P450 3A4 inhibitors or inducers * Has adult history of kidney stones and dysphagia * Has known history of alcohol/controlled substance abuse or are positive for drug of abuse screen * Currently on dialysis * Current serious illness such as cancer, HIV, cardiovascular event or hepatitis