RT Journal Article SR Electronic T1 Pharmacology of AMG 416 (Velcalcetide), a Novel Peptide Agonist of the Calcium-Sensing Receptor, for the Treatment of Secondary Hyperparathyroidism in Hemodialysis Patients JF Journal of Pharmacology and Experimental Therapeutics JO J Pharmacol Exp Ther FD American Society for Pharmacology and Experimental Therapeutics SP 229 OP 240 DO 10.1124/jpet.113.204834 VO 346 IS 2 A1 Walter, Sarah A1 Baruch, Amos A1 Dong, Jin A1 Tomlinson, James E. A1 Alexander, Shawn T. A1 Janes, Julie A1 Hunter, Tom A1 Yin, Qun A1 Maclean, Derek A1 Bell, Gregory A1 Mendel, Dirk B. A1 Johnson, Randolph M. A1 Karim, Felix YR 2013 UL http://jpet.aspetjournals.org/content/346/2/229.abstract AB A novel peptide, AMG 416 (formerly KAI-4169, and with a United States Adopted Name: velcalcetide), has been identified that acts as an agonist of the calcium-sensing receptor (CaSR). This article summarizes the in vitro and in vivo characterization of AMG 416 activity and the potential clinical utility of this novel compound. AMG 416 activates the human CaSR in vitro, acting by a mechanism distinct from that of cinacalcet, the only approved calcimimetic, since it can activate the CaSR both in the presence or the absence of physiologic levels of extracellular calcium. Administration of AMG 416 in vivo into either normal or renally compromised rats results in dose-dependent reductions in parathyroid hormone (PTH) levels and corresponding decreases in serum calcium, regardless of the baseline level of PTH. Treatment of 5/6 nephrectomized rats with AMG 416 resulted in dramatic improvements in their metabolic profile, including lower PTH and serum creatinine levels, reduced amounts of vascular calcification, attenuated parathyroid hyperplasia, and greater expression of the parathyroid gland regulators CaSR, vitamin D receptor, and FGF23 receptor compared with vehicle-treated animals. No drug accumulation was observed under this dosing regimen, and the terminal half-life of AMG 416 was estimated to be 2–4.5 hours. As a long-acting CaSR agonist, AMG 416 is an innovative new therapy for the treatment of hemodialysis patients with secondary hyperparathyroidism.