Background: Cinacalcet, a novel calcimimetic, simultaneously lowers parathyroid hormone (PTH), phosphorus (P), calcium (Ca) and Ca x P in patients who are on dialysis with secondary hyperparathyroidism (sHPT) associated with CKD. Previous studies have required cinacalcct to be administered during the dialysis session and at the same time on non-dialysis days. The aim of the SENSOR study was to demonstrate that cinacalcet given in a more clinically practical manner with the first major meal after dialysis is noninferior to cinacalcet given with food during the dialysis session. Methods: In this open-label study dialysis patients with poorly controlled sHPT (intact PTH (iPTH) > 300 pg/ml) were randomized to receive cinacalcet either daily with their post-dialysis meal (n = 337) or with food during the dialysis session (n = 336). The primary endpoint was the proportions of patients with mean iPTH ≤ 300 pg/ml (≤ 31.8 pmol/l) at Weeks 11 and 13 of a 21 -week treatment period. Secondary endpoints included the proportion of patients with Ca x P < 55 mg 2 /dl 2 (< 4.44 mmol 2 /l 2 ) at Weeks 11 and 13 and patients who discontinued the study due to nausea or vomiting. Results: Comparable proportions of patients in the cinacalcet "during dialysis" and "post-dialysis meal" groups had a mean iPTH ≤ 300 pg/ml (54 vs. 57%, respectively, 95% confidence interval (CI) difference -4, +10%) and Ca x P < 55 mg 2 /dl 2 (78 vs. 73%, respectively, 95% Cl difference - 11, +2%) at Weeks 11 and 13. The groups were also comparable at Week 21. Cinacalcet was well tolerated, with < 3% of patients in both groups discontinuing due to nausea or vomiting. A combined post-hoc analysis of both groups showed the incidence of nausea and vomiting was lower if cinacalcet was administered during the evening. Conclusions: Administering cinacalcet with the first main meal after dialysis was as effective as administration with food during the dialysis session. Cinacalcet was well tolerated. The incidence of gastrointestinal adverse events appeared to be lower when cinacalcet was administered in the evening.
