Official Title: “Efficacy and Safety of Paricalcitol on the Treatment of Moderate to Severe Secondary Hyperparathyroidism in Calcitriol Resistant Dialysis Subjects”

The primary objective of this study is to evaluate the efficacy and safety of paricalcitol in moderate to severe SHPT subjects under hemodialysis who are calcitriol-resistant.

Study Type: Interventional

Study Design: Treatment, Non-Randomized, Open Label, Single Group Assignment, Safety/Efficacy Study

Study Primary Completion Date: July 2010

Additional information for Arm Type, which is being reported as "Other". There will be only one arm constituted by subjects with confirmed calcitriol resistance. To confirm this resistance, subjects will begin a controlled calcitriol therapy period. After this period, those who fail to reduce PTH (according to parameters in protocol) will initiate paricalcitol therapy.

Intervention(s) in this Clinical Trial

• Drug: Calcitriol
  • Initial doses determined according to K/DOQI guideline. During therapy, calcitriol dose may be modified by 0.5 - 1 mcg at two to four weeks' intervals.
• Drug: Paricalcitol
  • Dose calculated by 0.04 to 0.1 microgram per kilogram (mcg/kg). Paricalcitol will be administered intravenously at any time during the subjects' dialysis. The paricalcitol dose will be titrated every 2 weeks until iPTH presents a reduction or up to 4 months, after which it will be adjusted monthly based on serum PTH, calcium, phosphorus and albumin measurements. Dosing may be modified by 2-4 mcg increments at two to four weeks' intervals.

Arms, Groups and Cohorts in this Clinical Trial

• Other: A
  • There will be only one arm constituted by subjects with confirmed calcitriol resistance. To confirm this resistance, subjects will begin a controlled calcitriol therapy period. After this period, those who fail to reduce PTH (according to parameters in protocol) will initiate paricalcitol therapy.

Primary Measures

• Proportion of subjects achieving at least a 50% reduction in iPTH in subjects treated with paricalcitol.
  • Time Frame: up to 3 months after paricalcitol therapy period
    Safety Issue?: No

Secondary Measures

• Adverse events occurrence will be considered secondary safety variable.
  • Time Frame: 1 year
    Safety Issue?: Yes

Inclusion Criteria:

• Male and female subjects > 18 years of age, with CKD stage V;
• Subjects on calcitriol therapy for at least six months before study entry and with PTH between 600 and 2000 pg/mL;
• Stable clinical conditions;
• Subject has voluntarily signed and dated an informed consent form, approved by an Institutional Review Board (IRB)/Independent Ethics Committee (IEC), after the nature of the study has been explained and the subject has had the opportunity to ask questions. The informed consent must be signed before any study-specific procedures are performed.

Exclusion Criteria:

• Previous parathyroidectomy
• Presence of hypercalcemia (corrected Ca* > 10.5 mg/dL) and/or hyperphosphatemia (P >
• 6.0 mg/dL) and/or Ca x P product (> 60)
• Severe and/or unstable clinical conditions, e.g., congestive heart failure, advanced cancer, advanced HIV disease, severe endocrinopathies, uncompensated diabetes mellitus, life-threatening cardiac arrhythmias, etc
• Abnormal liver tests (> 1.5 times above upper limit of normal)
• Pregnant or breast-feeding women
• Evidence of vitamin D toxicity
• Known hypersensitivity to any study drug components.
• Corrected calcium will be calculated by: [4 - subject's albumin value (g/dL)] x 0.8 + subject's serum calcium value

Gender Eligibility for this Clinical Trial: Both

Minimum Age for this Clinical Trial: 18 Years

Maximum Age for this Clinical Trial: N/A

Are Healthy Volunteers Accepted for this Clinical Trial?: No

Lead Sponsor: Abbott

Overall Clinical Trial Officials and Contacts

Overall Contact: Suely K Inoue, PharmD (55 11) 5536-7008 suely.kumagai@abbott.com

Information obtained from ClinicalTrials.gov on September 05, 2008

Link to the current ClinicalTrials.gov record. http://clinicaltrials.gov/show/NCT00664430

Study ID Number: W10-131

ClinicalTrials.gov Identifier: NCT00664430

Health Authority: Brazil: Ethics Committee