Cinacalcet in Paediatric Secondary Hyperparathyroidism (SHPT) Due to Chronic Kidney Disease (CKD)

Study Overview
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Brief Summary
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Twelve-month, multicenter, intra-subject controlled (retrospective-prospective), open-label, active-treatment study to evaluate the dose-response and pharmacokinetics (PK) of cinacalcet HCl for the treatment of Secondary Hyperparathyroidism (SHPT) in paediatric subjects with chronic kidney disease (CKD) on dialysis, followed by 12-month study extension.

Detailed Description
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This multicenter, intra-subject controlled, open-label, active-treatment study will assess in children affected by Secondary Hyperparathyroidism, aged 2-18 years on chronic dialysis not responsive to standard of care (SoC) therapy, the response after 6-month cinacalcet compared intra-subject to SoC alone at screening visit 6 months prior to cinacalcet start. Secondary objectives are to evaluate effects on growth over 18 months and PK profile. At baseline children have PTH levels>300 pg/mL, plasma P<6 mg/dL, and Ca 8.4-10.5 mg/dL, or Ca x P product>60 not responsive to SoC. Initial dosing of cinacalcet will be 0.5-0.75 mg/Kg per os OD to be adjusted up to a max of 180mg OD for target PTH values<180 pg/mL in absence of hypocalcemia. Thirty children will be enrolled at 12 centres participating in a national paediatric dialysis registry, corresponding to an α=0.05 and a power of 80% using the McNemar test, with an expected % of responders to cinacalcet or SoC of 40% or 5% respectively, with a drop-out rate of 15. Primary study endpoint (EP) will be the % of children who will have a reduction from baseline >25% in mean PTH levels during the 6-mo efficacy-assessment period. Among secondary EPs over 18 mos will be the % of patients with mean PTH levels<300 pg/mL; the % change in PTH, Ca, P values, and the Ca x P product; PK profile (or population profile by age) and its correlation with PTH and testosterone levels; auxological indices and growth velocity; % of children with treatment-emergent adverse events and lab abnormalities; retention on treatment and reasons of treatment withdrawal. The study will evaluate whether cinacalcet represents a safe and effective therapeutic option for SHPT children.

Official Title
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Twelve-month, Multicenter, Intra-subject Controlled (Retrospective-prospective), Open-label, Active-treatment Study to Evaluate the Efficacy, Safety, Tolerability and Pharmacokinetics (PK) of Cinacalcet Hydrochloride for the Treatment of Secondary Hyperparathyroidism (SHPT) in Paediatric Subjects With Chronic Kidney Disease (CKD) on Dialysis, Followed by 12-month Study Extension.

Conditions
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Secondary Hyperparathyroidism

Intervention / Treatment
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* Drug: Cinacalcet HCl


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Parents'/guardian written informed consent, and child's assent Age > 2 and <18 years; A dry body weight (BW) >10.49 Kg in males and >9.95 Kg in females, respectively; Inpatient or outpatient status at the time of enrolment; Males or females. Female subjects sexually active must be neither pregnant nor breastfeeding, and must lack childbearing potential from screening visit to the end of the safety follow-up On stable hemodialysis (HD) or peritoneal dialysis (PD) for their CKD for at least one month before entering the 6-month pre-treatment period; Plasma iPTH levels > 300 pg/mL, AND Plasma Ca levels > 9.4 mg/dL (with normal serum albumin level), AND Plasma P levels <6.5 mg/dL in patients younger than 6 years, or <6.0mg/dL in older patients, OR Ca x P product > 60; Records' availability for the following parameters 6 months prior to study entry: demographic information, physical examination, height and dry weight, auxological/anthropometric indices, blood pressure values, Kt/V urea, plasma iPTH, calcium, phosphorus, and alkaline phosphatise levels, blood pH and bicarbonate, serum creatinine/urea, C reactive protein (CRP) levels, liver function tests, blood count, blood 25(OH) vitamin D3 level. Exclusion Criteria: The following laboratory values: Hb<9.0 g/dL, WBC<2000/mm3 (2x109/L), platelets <150,000/mm3 (150x109/L) only in subjects who are otherwise eligible for PK/PD assessments; abnormal liver function, defined by a total bilirubin ≥2 times the upper limit of normal values, ASAT, ALAT, γ-GT levels ≥2 times the ULN values. Any other lab values that in the opinion of the investigator might place the subject at unacceptable risk for participation in the study. History of malignancy (active malignancy, or off therapy since less than 1 year) History of diseases causing hypercalcemia Chronic inflammatory diseases (C-Reactive Protein-CRP >2 times the upper limit of normal values) requiring a concomitant corticosteroid or immunosuppressive therapy History of infectious diseases (including opportunistic infections) within 4 weeks prior to study entry Evidence as assessed by the Investigator of active or latent bacterial, viral or fungal infections at the time of potential enrollment, including subjects with evidence of HIV infection. Hepatitis-B surface antigen-positive subjects only in subjects who are otherwise eligible for PK/PD assessments Hepatitis C antibody-positive subjects who are also PCR-positive or RIBA positive only in subjects who are otherwise eligible for PK/PD assessments Use of recombinant human growth hormone therapy Use of drugs that interact with cinacalcet disposition Previous use of cinacalcet

Ages Eligible for Study
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Minimum Age: 2 Years
Maximum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: cinacalcet tab or extemporaneous solution po added to SoC<br>Subjects who meet all inclusion/exclusion criteria at baseline will be given cinacalcet 30mg film-coated tablet, for oral use added to phosphate binders and vitamin D analogue. For subjects receiving a cinacalcet dose <30mg, commercially available cinacalcet 30mg tab will be ground and diluted with a 5% dextrose solution. Then, an aliquot of this solution corresponding to the individually prescribed dose will be administered as indicated. Initial dosing of cinacalcet will be 0.5-0.75mg/kg or 30 mg po once daily (OD) each evening with food. During the cinacalcet dose-titration 6-month period for efficacy assessment, the dose will be increased on monthly basis by 0.5 mg/kg or by 30mg OD to achieve the target iPTH value <180 pg/mL, as tolerated by the subject, up to maximum of 180mg OD in absence of signs of hypocalcemia, according to the current summary of product characteristics. | Drug: Cinacalcet HCl<br>* The 6-month pre-treatment period will be followed by a run-in period with a baseline evaluation prior to the drug administration, followed by a 6-month cinacalcet dose titration period, during which the dose will be increased on monthly basis by 0.5 mg/kg or by 30 mg OD up to the achievement of target iPTH value <180 pg/mL as tolerated by the patient<br>* Other names: Mimpara®;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Composite EP, e.g. the proportion of patients who will have a reduction from baseline of >= 25% in mean iPTH levels with concomitant values for plasma P <6 mg/dL and Ca between 8.4 and 10.5 mg/dL or the Ca x P product <60 | This composite EP will address the needed information on the appropriate dose of cinacalcet to be adopted in paediatric patients, and especially in younger children, as well as on the impact of treatment with calcimimetics on serum Ca and P levels, and on SHPT control over the long term | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The long term control of iPTH level < 300 pg/mL |  | 18 months | 
| The long term control of PTH, Ca, P, and the Ca x P product values |  | 18 months | 
| The PK/ PD ( iPTH and testosterone) profile at individual patient level |  | 12 months | 
| The long term auxological indices and patient growth velocity during cinacalcet treatment |  | 18 months | 
| The proportion of patients with treatment-emergent adverse events (AEs), serious AEs (SAEs), and laboratory abnormalities over long term |  | 18 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Cinacalcet, PK, Secondary Hyperparathyroidism, Paediatric, Chronic Kidney Disease, Dialysis