Effect of switching from etelcalcetide to upacicalcet in maintenance hemodialysis patients receiving treatment for secondary hyperparathyroidism

［Objective］This study aimed to investigate the efficacy and safety of switching from etelcalcetide to upacicalcet for secondary hyperparathyroidism in maintenance hemodialysis patients.［Methods］We retrospectively evaluated 90 hemodialysis patients (65 males, 25 females) undergoing treatment for secondary hyperparathyroidism who were switched from etelcalcetide to upacicalcet. The patients were divided into 4 groups according to the etelcalcetide dose：low-dose group (2.5 mg), medium-dose group (5 mg), high-dose group (7.5-10 mg), and very-high-dose group (15 mg). When switching, upacicalcet was started at 25 μg in all patients, and then the dose was adjusted to maintain whole-parathyroid hormone (PTH) levels within 35-150 pg/mL. Whole-PTH, phosphate, and calcium (Ca) levels were measured every 4 weeks.［Results］After switching, in high-dose and very-high-dose groups, Whole-PTH and corrected Ca levels increased, but subsequently decreased to pre-switch levels with increasing doses of upacicalcet. The target achievement rates of Whole-PTH levels after 48 weeks were：100, 88.7, 86.7, and 71.4％ in low-, medium-, high-, and very-high-dose groups, respectively, which were higher than before the switch. No adverse events such as hypocalcemia were observed.［Conclusion］Switching to upacicalcet in maintenance hemodialysis patients treated with etelcalcetide for secondary hyperparathyroidism involves no particular safety or efficacy concerns. However, careful attention should be paid to transient increases in Whole-PTH and corrected Ca levels when switching from more than 7.5 mg of etelcalcetide to 25 μg of upacicalcet.