The goal of this study is to test a new vitamin D compound for its ability to reduce parathyroid hormone levels in patients who are on hemodialysis.

This is a randomized, double-blind, placebo-controlled study of the vitamin D analog 2-methylene-19-nor-20S-1α,25-dihydroxyvitamin D3 (DP001) in patients with end-stage renal disease (ESRD). The effect of 12 weeks of oral administration of DP001 on serum parathyroid hormone (PTH) levels will be evaluated in ESRD patients who have secondary hyperparathyroidism.

Inclusion Criteria:

• Men and non-pregnant women ≥18 years of age
• Patient is diagnosed with ESRD and must be on hemodialysis 3 times per week for at least 3 months prior to Screening Phase
• Patient is currently being treated with pharmaceutical vitamin D for the treatment of secondary hyperparathyroidism
• Serum iPTH value ≤500 pg/mL at first screening visit
• Total serum calcium (corrected for albumin) ≤10.5 mg/dL at first screening visit
• Serum phosphorus ≤7.0 mg/dL at first screening visit

Exclusion Criteria:

• Currently taking any of the following: drugs affecting vitamin D metabolism, digitalis, glucocorticoids, cyclosporine or other immunosuppressants, aluminum-based phosphate binders
• A daily intake >4000 IU vitamin D (D3 + D2)
• Any investigational drug use within 10 half-lives of the drug (or within the previous 30 days if the half-life of the drug is unknown)
• History of any of the following: ventricular dysrhythmias, severe congestive heart failure, angina pectoris, myocardial infarction, coronary angioplasty, coronary artery bypass grafting, multiple myeloma, calciphylaxis, active malignancy, end-stage liver disease, active infections, clinically significant renal/urinary tract stones, sarcoidosis, tuberculosis, parathyroidectomy
• Major surgery within the past 3 months