Role of etecalcetide in the management of secundary hyperparathyroidism

Abstract Background and Aims Secondary Hyperparathyroidism (SHPT) is a complication of chronic kidney disease (CKD). Etelcalcetide is the first intravenous calcimimetic authorized for the treatment of SHPT in haemodialysis (HD). It has proven to be effective in lowering parathyroid hormone (PTH), with an acceptable and comparable safety profile. The aim of this descriptive study was to evaluate the results of using etelcalcetide in patients on HD with SHPT. Method Thirty patients on HD received etelcalcetide were enrolled (figure 1). The minimum observation period was 6 months. Fifteen (50%) were previously with cinacalcet (group 1) and 15 (50%) received etelcalcetide at onset (group 2). We analyzed change of serum iPTH, calcium (Ca) and phosphorus (P) in both cohorts; as well as the dosage of calcium carbonate, non-calcium (phosphate binders) and / or vitamin D analogs. The presence of adverse effects were also recorded. Results Thirty patients on HD received etelcalcetide were enrolled (figure 1). The minimum observation period was 6 months. Fifteen (50%) were previously with cinacalcet (group 1) and 15 (50%) received etelcalcetide at onset (group 2). We analyzed change of serum iPTH, calcium (Ca) and phosphorus (P) in both cohorts; as well as the dosage of calcium carbonate, non-calcium (phosphate binders) and / or vitamin D analogs. The presence of adverse effects were also recorded. In global, serum iPTH levels were significantly decreased during therapy compared to baseline levels. When comparing both groups, we found a significant decrease of Ca, P and iPTH in group 2. However, we only found significant decrease of Ca in group 1 (figure 2). When we analyzed the reducton of PTH >30% in both groups, we observed that 46.6% of patients treated with etecalcetide compared to 33.3% of patients treated with cinacalcet, achieved this reduction in PTH. The dosage of calcium binders (33.3% pretreatment vs 56.7% at the end of follow-up, p 0.054), non-calcium binders (40% pretreatment vs 63.3% at the end of follow-up, p 0.02) and vitamin D analogues (56,7% pretreatment vs 66,7% at the end of follow-up, p 0,3) were increased when etelcalcetide treatment was started. No changes were made in dialysate calcium concentration. Six patients, presented hypocalcemia (Ca < 7.5 mEq/l). Conclusion In our cohort, etelcalcetide has shown to be effective in reducing serum iPTH. In addition, etecalcetide was noninferior to cinacalcet reducing PTH>30%. An increase in the use of vitamin D analogues, calcium binders and non-calcium binders has been observed, probably due to the hypocalcemia.