as salt: InChI=1S/C38H73N21O10S2.ClH/c1-18(28(62)56-22(27(40)61)8-4-12-49-35(41)42)53-30(64)23(9-5-13-50-36(43)44)58-32(66)25(11-7-15-52-38(47)48)59-31(65)24(10-6-14-51-37(45)46)57-29(63)19(2)54-33(67)26(55-20(3)60)17-71-70-16-21(39)34(68)69;/h18-19,21-26H,4-17,39H2,1-3H3,(H2,40,61)(H,53,64)(H,54,67)(H,55,60)(H,56,62)(H,57,63)(H,58,66)(H,59,65)(H,68,69)(H4,41,42,49)(H4,43,44,50)(H4,45,46,51)(H4,47,48,52);1H/t18-,19-,21+,22-,23-,24-,25-,26-;/m1./s1
Etelcalcetide is used for the treatment of secondary hyperparathyroidism in people with chronic kidney disease (CKD) on hemodialysis.[7] Hyperparathyroidism is the condition of elevated parathyroid hormone (PTH) levels and is often observed in people with CKD.[8]
Pharmacodynamics
Mechanism of action
Etelcalcetide functions by binding to and activating the calcium-sensing receptor (CaSR) in the parathyroid gland as an allosteric activator, resulting in PTH reduction and suppression.[3]
Pharmacokinetics
Etelcalcetide functions in a first order elimination, with a half life of 19 hours.[6]
Common side effects (in more than 10% of people) are nausea, vomiting, diarrhoea, muscle spasms, and hypocalcaemia (too low blood calcium levels). In clinical studies, the latter side effect was usually mild to moderate and without symptoms. An increase of the QT interval of more than 60 ms was detected in 1.2% of people receiving etelcalcetide.[7][9]
Due to the lower iPTH levels achieved by the use of this drug, it is possible that adynamic bone disease could occur at levels "below 100 pg/mL"[6]
The substance is a peptide consisting mostly of D-amino acids instead of the common L-amino acids. More specifically, it is the disulfide of N-acetyl-D-cysteinyl-D-alanyl-D-arginyl-D-arginyl-D-arginyl-D-alanyl-D-argininamide with L-cysteine.[10]
History
Originally, Etelcalcetide was being developed by KAI Pharmaceuticals. After positive phase II trials, Amgen acquired KAI for $315 million.[11]
In 2011, KAI entered into agreement with Ono Pharmaceutical for production of Etelcalcetide in Japan, the deal being worth ¥1 billion.[6]
In February 2017, the FDA approved Parsabiv for the treatment of secondary hyperparathyroidism.[12]
Research
Phase II trials found that Etelcalcetide was able to lower PTH levels in one cohort by -49% vs a 29% increase in the placebo group.[6] In another phase II study "89% of patients experienced a C30% reduction in PTH and 56% achieved a PTH level of B300 pg/mL."[6]
In 2017, two phase III trials found that using etelcalcetide showed greater symptom reduction compared to placebo.[13] Etelcalcetide was also able to lower PTH levels below 300pg/mL more often.[13]
Phase I pediatric studies are planned for the US and UK for etelcalcetide.[6]