An open-label study to evaluate a single-dose of cinacalcet in pediatric dialysis subjects.
BACKGROUND
There is limited knowledge of the effectiveness and safety profile of cinacalcet in pediatric patients with secondary hyperparathyroidism (sHPT) treated with dialysis.


METHODS
This was an open-label, single-dose study conducted on 12 pediatric subjects with chronic kidney disease treated with dialysis. Subjects were stratified by four age cohorts and given a single 15-mg oral dose of cinacalcet. Multiple blood samples were collected up to 72 h post-dose for the assessment of serum calcium (Ca), serum intact parathyroid hormone (iPTH), and plasma cinacalcet concentrations.


RESULTS
Overall, cinacalcet was well tolerated with no serious adverse events. Mean (standard deviation) percentage change in serum Ca over the first 12 h post-dose was -2.93 % (5.70 %) with a nadir of -4.34 % (6.04 %) at 8 h; Ca values returned to baseline by 48 h post-dose. Mean percentage change in iPTH over the first 12 h post-dose was 57.94 % (71.82 %) with a nadir of -35.65 % (55.82 %) at 2 h. There was an inverse relationship between peak serum Ca concentration and body surface area (BSA) (r (2) = 0.41), although no relationship was found between area under the curve and age or BSA.


CONCLUSIONS
These data support future analysis to determine the therapeutic starting dose of cinacalcet for pediatric patients with sHPT on dialysis.
Early Development, Amgen Inc., One Amgen Center Dr., M/S 38-3-A, Thousand Oaks, CA 91320, USA. dpadhi@amgen.com
Desmond
D
Padhi
Craig B
CB
Langman
Sahar
S
Fathallah-Shaykh
Bradley A
BA
Warady
Isidro B
IB
Salusky
Edward
E
Lee
Christine
C
Wang
Edward
E
Posvar
D000284:Administration, Oral; D000293:Adolescent; D000367:Age Factors; D019540:Area Under Curve; D015415:Biomarkers / Q000097:blood; D001830:Body Surface Area; D057966:Calcimimetic Agents / Q000008:administration & dosage* / Q000009:adverse effects / Q000097:blood / Q000493:pharmacokinetics; D002118:Calcium / Q000097:blood; D002648:Child; D000069449:Cinacalcet; D054796:Drug Dosage Calculations; D005260:Female; D006801:Humans; D006962:Hyperparathyroidism, Secondary / Q000097:blood / Q000188:drug therapy* / Q000209:etiology; D008297:Male; D009281:Naphthalenes / Q000008:administration & dosage* / Q000009:adverse effects / Q000097:blood / Q000493:pharmacokinetics; D010281:Parathyroid Hormone / Q000097:blood; D011446:Prospective Studies; D006435:Renal Dialysis / Q000009:adverse effects; D051436:Renal Insufficiency, Chronic / Q000097:blood / Q000150:complications / Q000628:therapy*; D016896:Treatment Outcome; D014481:United States
D015415:Biomarkers; D057966:Calcimimetic Agents; D009281:Naphthalenes; C470125:PTH protein, human; D010281:Parathyroid Hormone; D002118:Calcium; D000069449:Cinacalcet