Effect of switching from cinacalcet to etelcalcetide on secondary hyperparathyroidism in patients undergoing hemodialysis: an ESCORT trial

Background Etelcalcetide is the first intravenously administered calcimimetic agent used to manage secondary hyperparathyroidism (SHPT) in hemodialysis (HD) patients. We evaluated the safety and efficacy of replacing cinacalcet with etelcalcetide in HD patients. Methods One hundred and thirty-three patients HD on cinacalcet were screened, and 93 patients with serum-intact parathyroid hormone (iPTH) level of [greater than or equai to] 60 pg/mL and serum albumin-corrected calcium (cCa) level of [greater than or equai to] 8.4 mg/dL were enrolled. The patients were divided into three groups based on the dose of cinacalcet (i.e., 25, 50, and [greater than or equai to] 75 mg) and switched to etelcalcetide. Etelcalcetide was administered three times per week for 24 weeks. The primary and secondary endpoints were etelcalcetide conversion dose and etelcalcetide effectiveness for iPTH levels (target range: 60-240 pg/mL), respectively. Results Of the 68 patients whose iPTH level was within the management target at screening, 60 patients maintained the target level at the end of the study. Among patients whose iPTH level exceeded 240 pg/mL at screening, it decreased from 401 [+ or -] 246 pg/mL to 220 [+ or -] 209 pg/mL (p < 0.001) at the end of the study. Among 22 patients with the iPTH level of [greater than or equai to] 240 pg/mL, 17 achieved the target level. The mean dose of cinacalcet was 41.4 [+ or -] 22.2 mg/day and that of etelcalcetide at the end of the study was 6.4 [+ or -] 3.7 mg/session in all patients. In 45 patients whose iPTH level was within the management target throughout the study and active vitamin D agent and calcium-based phosphate binder doses were constant, the mean dose of cinacalcet was 45.0 [+ or -] 22.4 mg/day and that of etelcalcetide at the end of the study was 6.1 [+ or -] 3.1 mg/session. The spKt/V might affect the ratio of etelcalcetide per session to oral cinacalcet per day (45 patients, p = 0.087; 90 patients, p < 0.05) in the generalized linear model. Etelcalcetide-induced severe adverse events were not observed. Conclusions This study reports the conversion dose of etelcalcetide and demonstrates its safety and efficacy in HD patients with SHPT previously treated with cinacalcet. Trial registration UMIN, UMIN000027637; Registered on June 5, 2017. Keywords: Cinacalcet, Etelcalcetide, Hemodialysis, Intact-PTH, Secondary hyperparathyroidism