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: June 2009

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 after 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

• Efficacy will be assessed on visit 15 by the proportion of subjects who reduce PTH levels in 50% relative to visit 4 values. For subjects who do not perform visit 4, the reduction of the PTH levels in 50% will be assessed relative to visit 5 values.
  • Time Frame: As soon as the subjects reduce PTH levels in 50% according to the protocol
    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 with diagnosis of calcitriol resistance defined as: Episodes of hypercalcemia and/or hyperphosphatemia (defined as an episode of calcium or phosphorus above Upper
• Limit of Normal or documented by medical history stating that the treatment with calcitriol was discontinued due to hypercalcemia and/or hyperphosphatemia) that precludes treatment continuation and/or persistent PTH above 600pg/mL during the calcitriol therapy;
• PTH value at screening visit between 600 pg/mL and 2000 pg/mL;
• Stable clinical conditions;
• Subject has voluntarily consented to participate in the study, by signing and dating 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 all his questions about the study have been elucidated. 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, at screening visit;
• 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 serum albumin (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

Information obtained from ClinicalTrials.gov on July 02, 2009

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