Bioequivalence Study Comparing Calcium Acetate Oral Solution Versus Calcium Acetate Gelcaps in Healthy Volunteers

Inclusion Criteria: * Signed and dated informed consent form * Ages: 18-75 years * Serum Calcium level 8.6-10.2 mg/dL * 25 vitamin D level 20-100 ng/mL * 1, 25 dihydroxy vitamin D level 6-62 pg/mL * Fasting glucose level of 65-99 mg/dL (min 8 hr fast) * iPTH level of 10-65 pg/mL * Serum phosphorous level of 2.5-4.5 mg/dL * Albumin level of 3.6-5.1 g/dL * Sodium level of 135-146 mEq/L * Potassium level of 3.5-5.3 mEq/L * Negative pregnancy test (at screening and prior to dosing) for women of childbearing potential and subjects must agree to use adequate contraception (hormonal or double barrier method) during the study * No clinically significant abnormalities on electrocardiogram (ECG) reading as determined by the INVESTIGATOR * No clinically significant abnormalities on liver function tests * No clinically significant abnormalities on CBC and coagulation studies * No clinically significant abnormalities on kidney function (eGFR using serum creatinine) * BMI between 18.5-30 * Subjects must agree not to consume alcohol while in the treatment phase of the study Exclusion Criteria: * Women who are pregnant or breast feeding * Malignancy except squamous cell carcinoma of the skin * Documented current acute or chronic disease * Positive for human immunodeficiency virus (HIV), hepatitis B or hepatitis C * Myocardial infarction within 6 months of study Day 0 * Parathyroidectomy within 6 months of study Day 0 * Gastrointestinal disorder associated with impaired absorption of oral medications * Inability to swallow tablets or tolerate calcium acetate oral solution * Hormonal therapy (except for contraceptives), immunotherapy or corticoid therapy * Concurrent antibiotic treatment * Any concurrent investigational treatment within 30 days of screening * Unable or unwilling to comply fully with the protocol * Diuretic therapy such as Thiazides, Furosemide (INN) or frusemide (former BAN) within one month before screening * Subjects taking over-the-counter (OTC) or prescribed phosphorous or calcium containing supplements * Subjects testing positive for drugs of abuse