Safety and efficacy of etelcalcetide, an intravenous calcimimetic, for up to 52 weeks in hemodialysis patients with secondary hyperparathyroidism: results of a post-marketing surveillance in Japan.

backgroundEtelcalcetide is a second-generation calcimimetic for the management of secondary hyperparathyroidism (SHPT) in patients on dialysis. We performed a post-marketing surveillance (PMS) to obtain information on the safety and efficacy of etelcalcetide in clinical practice in Japan.

methodsThis PMS enrolled SHPT patients who started initial treatment with etelcalcetide between April 1, 2017 and February 28, 2018 in Japan. Safety [adverse drug reactions (ADRs)] and efficacy [serum intact parathyroid hormone (iPTH), corrected calcium (cCa), phosphorous (P), and alkaline phosphatase (ALP)] were recorded for up to 52 weeks or until treatment discontinuation. Treatment decisions were at the physician's discretion.

resultsOf 1226 patients enrolled across 282 centers, safety and efficacy data were available for 1195 and 1192, respectively, while 933 continued treatment to Week 52. The starting dose was 5 mg in 82.0% of patients. There were 218 ADRs in 169 patients (14.1%). Metabolism and nutrition disorders (8.8%), adverse laboratory test results (1.8%), and gastrointestinal disorders (1.6%) were the most frequent classes of ADRs. Hypocalcemia-related ADRs occurred in 104 patients (8.7%). The percentage of patients with iPTH levels within the target range (60-240 pg/mL) steadily increased from 19.5% at Week 0 to 64.1% at Week 52 or last dose. cCa, P, and ALP levels remained well controlled.

conclusionThis was the first real-world, large-scale, long-term observational PMS of etelcalcetide in Japan. We did not observe any new safety concerns. Etelcalcetide was associated with clinically relevant improvements in serum iPTH and maintenance of serum cCa, P, and ALP levels.