Vitamin D receptor activators and calcimimetics (calcium-sensing receptor agonists) are two major options for medical treatment of secondary hyperparathyroidism. A higher serum calcification propensity (a shorter T 50 value) is a novel surrogate marker of calcification stress and mortality in patients with CKD. We tested a hypothesis that a calcimimetic agent etelcalcetide is more effective in increasing T 50 value than a vitamin D receptor activator maxacalcitol.
A randomized, multicenter, open-label, blinded end point trial with active control was conducted in patients with secondary hyperparathyroidism undergoing hemodialysis in Japan. Patients were randomly assigned to receive intravenous etelcalcetide 5 mg thrice weekly (etelcalcetide group) or intravenous maxacalcitol 5 or 10 µg thrice weekly (maxacalcitol group). The primary, secondary, and tertiary outcomes were changes in T 50 value, handgrip strength, and score of the Dementia Assessment Sheet for Community-Based Integrated Care System from baseline to 12 months, respectively.
In total, 425 patients from 23 dialysis centers were screened for eligibility, 326 patients were randomized (etelcalcetide, n=167; control, n=159), and 321 were included in the intention-to-treat analysis (median age, 66 years; 113 women [35%]). The median (interquartile range) of T 50 value was changed from 116 minutes (interquartile range, 90–151) to 131 minutes (interquartile range, 102–176) in the maxacalcitol group, whereas it was changed from 123 minutes (interquartile range, 98–174) to 166 minutes (interquartile range, 127–218) in the etelcalcetide group. The increase in T 50 value was significantly greater in the etelcalcetide group (difference in change, 20 minutes; 95% confidence interval, 7 to 34 minutes; P=0.004). No significant between-group difference was found in the change in handgrip strength or in the Dementia Assessment Sheet for Community-Based Integrated Care System score.