The goal of this clinical trial is to evaluate safety, tolerability, and how CTAP101 Capsules work to treat Pediatric Participants with Secondary Hyperparathyroidism, Stage 3 or 4 Chronic Kidney Disease and Vitamin D Insufficiency. The main questions it aims to answer are:
1. To assess the pharmacokinetics (PK) and Pharmacodynamics (PD) of CTAP101 Capsules 2. To investigate the safety and tolerability of CTAP101 Capsules
Participants will take a daily dosage of CTAP101 Capsules at bedtime for 8 weeks.
Be 8 to <18 years of age with a body weight of ≥40 kg.
Be diagnosed with stage 3 or 4 CKD at least six months prior to the screening visit (Visit 1) and have an eGFR of ≥15 to <60 mL/min/1.73m2 at screening.
Be without any disease state or physical condition that might impair evaluation of safety or which, in the investigator's opinion, would interfere with study participation.
Plasma iPTH >85 pg/mL;
Kidney transplant within the 26 weeks preceding screening or kidney transplant rejection within the 26 weeks preceding screening.
No history of parathyroidectomy or planned parathyroidectomy.
History (prior three months) of serum Ca ≥9.8 mg/dL.
Use of calcimimetic or calcifediol therapy within three months prior to consent.