A Study to Evaluate Safety, Efficacy and Pharmacokinetics of Paricalcitol For Treatment of Secondary Hyperparathyroidism (SHPT) in Pediatric Participants With Stage 5 Chronic Kidney Disease (CKD)

The main objective of this study is to evaluate the safety, efficacy and pharmacokinetics of paricalcitol oral solution in pediatric participants of ages 0 to 9 years with SHPT associated with stage 5 CKD receiving Peritoneal Dialysis (PD) or Hemodialysis (HD). The 24-week study is divided into two 12-week dosing periods (Dosing Period 1 followed by Dosing Period 2).

Inclusion Criteria: * Participant is currently diagnosed with and/or being treated for secondary hyperparathyroidism (SHPT). * Participant must be diagnosed with chronic kidney disease (CKD) stage 5 receiving peritoneal dialysis (PD) or hemodialysis (HD) for at least 30 days prior to initial Screening. * For entry into the Washout Period (for vitamin D receptor activator \[VDRA\] non-naive participants), the participant must meet the appropriate laboratory criteria based upon the participant's age as described in the protocol. * For entry into the Dosing Period (for VDRA-naive participants or VDRA non-naive participants who have completed the Washout Period), the participant must meet the appropriate laboratory criteria based upon the participant's age as described in the protocol. Exclusion Criteria: * Participant is scheduled to receive a living donor kidney transplant within 3 months of Screening or is a kidney transplant recipient. * Participant is expected to discontinue peritoneal dialysis (PD) or hemodialysis (HD) within 3 months of the initial Screening visit. * Participant has had a parathyroidectomy within 12 weeks prior to Screening. * Participant is taking maintenance calcitonin, bisphosphonates, glucocorticoids (in a dose equivalent to \> 0.16 mg/kg/day or 5 mg prednisone/day, whichever is lower), 4 weeks prior to Dosing. * Participant is receiving calcimimetics at the time of Screening or is expected to initiate calcimimetics at any time throughout the study. * Participant is unable to take oral medications.