A Prospective, Randomized Clinical Trial of Etelcalcetide in Patients Receiving Hemodialysis With Secondary Hyperparathyroidism (the DUET Trial)

Introduction The clinical trial on the Development of a treatment strategy for chronic kidney disease‒mineral and bone disorder by a mUltilateral mechanism of ETelcalcetide hydrochloride, or the DUET trial, was designed to determine the efficacy of etelcalcetide, an intravenous calcimimetic, for control of secondary hyperparathyroidism (SHPT). Methods Eligible SHPT maintenance hemodialysis patients (n = 124) were randomized (1:1:1) for inclusion in the DUET trial, a 12-week, multicenter, open-label, parallel-group study (jRCTs041180108), and assigned to either an etelcalcetide + active vitamin D group (group E+D), an etelcalcetide + oral calcium preparation group (group E+Ca), or a control group (group C). The primary endpoint was number of patients with a 50% reduction from baseline of intact parathyroid hormone (iPTH) levels, and iPTH levels ≤ 240 pg/mL at 12 weeks after start of the trial. Results The proportion of patients reaching the primary endpoint (95% confidence interval [CI]) was 90.0% (76.3%–97.2%) in group E+D, 56.8% (39.5%–72.9%) in group E+Ca, and 19.5% (8.8%–34.9%) in group C. Etelcalcetide treatment led to a significant increase in the number of patients achieving the endpoint (odds ratio, 13.4; 95% CI, 5.10–35.3) on logistic regression analysis, with iPTH, corrected serum calcium, and phosphate at baseline as covariates. Significantly more patients achieved the endpoint in group E+D compared with group E+Ca (odds ratio, 6.35; 95% CI, 1.79–22.48). There were fewer hypocalcemic visits in group E+D compared with group E+Ca (P = 0.018), yet the former group was prone to hyperphosphatemia. Conclusion Etelcalcetide showed good control of iPTH for maintenance hemodialysis patients with SHPT. Active vitamin D was useful in correcting hypocalcemia, but the oral calcium preparation was superior for suppression of hyperphosphatemia.