Efficacy of Evocalcet in Previously Cinacalcet-Treated Secondary Hyperparathyroidism Patients

Abstract

Introduction: Evocalcet is a recently approved calcimimetic agent for secondary hyperparathyroidism (SHPT). In this study, the efficacy and safety of once-daily oral evocalcet were evaluated in patients without prior cinacalcet use (nonusers) and previously treated patients (users).

Methods: This post hoc analysis of a previous phase III head-to-head comparison study included SHPT patients treated with evocalcet with or without prior cinacalcet use. Endpoints included trends in the median intact and whole parathyroid hormone (PTH), mean corrected calcium, phosphate, and bone metabolic markers, and whole-to-intact PTH ratios throughout the 30-week study period; proportions of patients achieving target intact PTH, corrected calcium, and phosphate at weeks 28 to 30; and adverse drug reactions (ADRs).

Results: This study included 127 nonusers and 190 users with significant differences in age; duration of dialysis; use of intravenous vitamin D receptor activators; levels of intact PTH, corrected calcium, tartrate-resistant acid phosphatase 5b, procollagen type 1 N-terminal-propeptide; and largest parathyroid gland volume (P < 0.05 for all characteristics) between 2 groups at baseline. Users required higher evocalcet dosages than nonusers. Similar efficacy results were found in the 2 groups except for a significantly higher proportion of nonusers achieving the intact PTH target (81.6% vs 67.1%, difference [95% confidence interval], -14.5% [-24.59, -3.34]), and a significant reduction in largest parathyroid gland volume from week 0 to week 30 (-120.6 [567.2] mm³, P = 0.043). No difference was found in ADRs between the 2 groups.

Conclusion: Treatment with evocalcet is effective and safe irrespective of prior cinacalcet treatment in SHPT patients.

Keywords: calcium; cinacalcet; evocalcet; parathyroid gland volume; parathyroid hormone; secondary hyperparathyroidism.

Graphical abstract

Figure 1

Trends in the (a) median (interquartile range) serum intact PTH levels, (b) mean (SD) serum corrected calcium, and (c) serum phosphate levels throughout the study period (week 0 to week 30) in cinacalcet nonusers and users. Yellow-shaded area indicates a guideline target range. PTH, parathyroid hormone.

Figure 2

Trends in the mean (standard deviation) serum (a) BAP, (b) TRACP-5b, and (c) P1NP, and median (interquartile range) intact (d) FGF23 levels throughout the study period (week 0 to week 30) in cinacalcet nonusers and users. BAP, bone-specific alkaline phosphatase; FGF23, fibroblast growth factor 23; P1NP, procollagen type 1 N-terminal propeptide; TRACP-5b, tartrate-resistant acid phosphatase 5b.