Phase 1, single-dose study to assess the safety, tolerability, pharmacokinetics, and pharmacodynamics of etelcalcetide in pediatric patients with secondary hyperparathyroidism receiving hemodialysis.

BACKGROUND Data on the safety, efficacy of etelcalcetide in children with secondary hyperparathyroidism (sHPT) are limited. METHODS This phase 1 study (NCT02833857) evaluated the safety, tolerability, pharmacokinetics (PK), pharmacodynamics (PD) of single-dose etelcalcetide (0.035 mg/kg intravenously) in pediatric hemodialysis patients (two cohorts; 1: 12- 2.25 mmol/L. After etelcalcetide dosing, PK exposures declined, with mean Cmax, AUClast, and AUCinf exposures higher in cohort 1. Median percent change in serum intact parathyroid hormone (iPTH) from baseline (cohort 1: 51.2 pmol/L; cohort 2: 84.0 pmol/L) reached the nadir on D1 at 4 h (cohort 1: - 33.4%; cohort 2: - 64.2%). Mean total calcium and cCa reached nadirs on D3 at 2.39 mmol/L, and ionized Ca on D1 at 4 h. CONCLUSIONS Single-dose etelcalcetide (0.035 mg/kg) was well tolerated with expected PK and safety profiles. Overall pattern of changes in serum iPTH and serum calcium was similar between cohorts and consistent with expected responses to etelcalcetide.