A Study to Evaluate the Safety and Efficacy of Paricalcitol Capsules in Reducing Serum Intact Parathyroid Hormone Levels in End Stage Renal Disease Subjects on Peritoneal Dialysis

Inclusion criteria

• Subject is greater than or equal to 18 years.
• Subject is diagnosed with ESRD and must be on continuous PD 7 days per week for at least 2 months prior to Screening Phase.
• If female, subject is either not of childbearing potential or is of childbearing potential and practicing one of the recommended methods of birth control.
• If female, subject must have a negative serum pregnancy test prior to treatment.
• If female, subject is not breastfeeding.
• Subject is undergoing full PD regimen and is expected to remain on this PD regimen for the duration of the study.
• For those subjects who have been taking a phosphate binder prior to therapy, the subject has been on a stable type of phosphate binder at least 4 weeks prior to the Pre-Treatment Phase.
• For entry into the Pretreatment Phase the subject must have: Calcium level less than or equal to 10.5 mg/dL and Ca x P level less than or equal to 65.
• For entry into the Treatment Phase the subject must have: iPTH greater than or equal to 300 pg/mL, calcium level of 8.0 to 10.5 mg/dL, inclusive, and Ca x P less than or equal to 65.
• Subject has voluntarily signed and dated an IRB approved informed consent.

Exclusion criteria

• Subject has history of an allergic reaction or significant sensitivity to drugs similar to the study drug
• Subject has had active peritonitis within 1 month prior to screening phase.
• Subject has had more than one episode of peritonitis within 4 months prior to screening phase.
• Subject has received a partial parathyroidectomy within 1 year prior to screening phase.
• Subject has had acute renal failure within 3 months of screening phase.
• Subject has chronic gastrointestinal disease.
• Subject has taken aluminum-containing phosphate binders for greater than 3 weeks in the last 3 months prior to the screening phase or will require these medications greater than 3 weeks in the study.
• Subject has a current malignancy or clinically significant liver disease.
• Subject has a history of drug or alcohol abuse within 6 months prior to screening phase.
• Subject has evidence of poor compliance with diet, medication, or PD.
• Subject has participated in any investigational drug or device study within 4 weeks prior to the treatment phase.
• Subject is taking maintenance calcitonin, glucocorticoids, or other drugs that may affect calcium or bone metabolism, other than females on stable estrogen and/or progestin therapy.
• For any reason, subject is considered by the investigator to be an unsuitable candidate to receive paricalcitol capsules.
• Subject is known to be HIV positive.