The effects of discontinuing cinacalcet at the time of kidney transplantation.

Background. The calcimimetic, cinacalcet, is approved for treating secondary hyperparathyroidism (SHPT) in patients with chronic kidney disease (CKD) on dialysis. Biochemical profiles and clinical outcomes in patients discontinuing cinacalcet at kidney transplantation have not been previously described.Methods. We performed a retrospective observational study evaluating post-transplant biochemical profiles and clinical outcomes in patients who had enrolled in phase 2 or 3 randomized, placebo-controlled studies of cinacalcet before receiving a kidney transplant.Results. The study included 28 former cinacalcet and 10 former placebo patients. Post-kidney transplant, there were no obvious differences between the two groups in levels of serum intact parathyroid hormone, calcium or phosphorus. One patient in each group underwent post-transplant parathyroidectomy. Kidney transplant failure was apparent in one former cinacalcet-treated patient (4%) and three former placebo patients (30%). The duration of hospitalization (mean +/- standard error) immediately post-transplant in these two groups was 2.3 +/- 0.3 and 3.4 +/- 0.8 weeks, respectively.Conclusions. Using cinacalcet to treat SHPT in patients with CKD awaiting kidney transplantation does not appear to modify SHPT-related post-transplant biochemical profiles, or clinical outcomes, compared with placebo.

Impact of vitamin D dose on biochemical parameters in patients with secondary hyperparathyroidism receiving cinacalcet.

BACKGROUND/AIMS: The calcimimetic cinacalcet (Mimpara/Sensipar) simultaneously lowers parathyroid hormone (PTH), phosphorus (P) and calcium (Ca) levels in patients with secondary hyperparathyroidism. The OPTIMA study demonstrated that cinacalcet and adjusted doses of vitamin D maximized control of these parameters. This post-hoc analysis of OPTIMA data assessed the impact of reducing or increasing the dose of concomitant vitamin D on PTH, P and Ca in patients receiving cinacalcet. METHODS: Dialysis patients with mean baseline intact PTH (iPTH) 300-800 pg/ml (31.8-84.8 pM) received doses of cinacalcet titrated to achieve an iPTH of 150-300 pg/ml (15.9-31.8 pM). The dose of vitamin D could then be decreased to further reduce serum P or Ca, or increased/initiated to further decrease PTH levels if iPTH >300 pg/ml or to increase Ca if Ca <8.0 mg/dl (2.0 mM). RESULTS: Vitamin D dose was assessed for 345 patients during a 23-week period. A total of 91 and 129 patients had an increase or decrease in vitamin D dose, respectively. By study end, mean iPTH, P, and Ca were similar in both vitamin D groups, although there were differences in biochemical parameters between groups at the start of the study. There were statistically significant reductions from baseline to study end in iPTH and Ca in both groups (p < 0.001). Although P was significantly reduced by week 23 in the group in which vitamin D dose was decreased (p = 0.007), the reduction in P was less and did not achieve significance in the group in which vitamin D dose was increased (p = 0.71). CONCLUSIONS: After initiating cinacalcet, the dose of vitamin D can be adjusted to maximize reductions in PTH, P and Ca; however, vitamin D-induced decreases in PTH need to be balanced with the diminished response in P and Ca.

The OPTIMA study: assessing a new cinacalcet (Sensipar/Mimpara) treatment algorithm for secondary hyperparathyroidism.

BACKGROUND AND OBJECTIVES: Cinacalcet, a novel calcimimetic, targets the calcium-sensing receptor to lower parathyroid hormone (PTH), calcium, and phosphorus levels in dialysis patients with secondary hyperparathyroidism (SHPT). This study compared the efficacy of a cinacalcet-based regimen with unrestricted conventional care (vitamin D and phosphate binders) for achieving the stringent National Kidney Foundation Kidney Disease Outcomes Quality Initiative (KDOQI) targets for dialysis patients. STUDY DESIGN: In this multicenter, open-label study, hemodialysis patients with poorly controlled SHPT were randomized to receive conventional care (n = 184) or a cinacalcet-based regimen (n = 368). Doses of cinacalcet, vitamin D sterols, and phosphate binders were adjusted during a 16-wk dose-optimization phase with the use of algorithms that allowed cinacalcet to be used with adjusted doses of vitamin D. The primary end point was the proportion of patients with mean intact PTH < or =300 pg/ml during a 7-wk efficacy assessment phase. RESULTS: A higher proportion of patients receiving the cinacalcet-based regimen versus conventional care achieved the targets for PTH (71% versus 22%, respectively; P < 0.001), Ca x P (77% versus 58%, respectively; P < 0.001), calcium (76% versus 33%, respectively; P < 0.001), phosphorus (63% versus 50%, respectively; P = 0.002), and PTH and Ca x P (59% versus 16%, respectively, P < 0.001), and allowed a 22% reduction in vitamin D dosage in patients receiving vitamin D at baseline. Achievement of targets was greatest in patients with less severe disease (intact PTH range, 300 to 500 pg/ml) and the cinacalcet dose required was lower in these patients (median = 30 mg/d). CONCLUSIONS: Compared with conventional therapy, a cinacalcet-based treatment algorithm increased achievement of KDOQI treatment targets in dialysis patients in whom conventional therapy was no longer effective in controlling this disease.

Long-term treatment of secondary hyperparathyroidism with the calcimimetic cinacalcet HCl.

BACKGROUND: Patients with secondary hyperparathyroidism often require therapy that provides long-term control of parathyroid hormone concentrations without increasing calcium and phosphorus concentrations. Cinacalcet modulates the calcium-sensing receptor on the parathyroid gland to reduce secretion of parathyroid hormone and lower serum calcium, phosphorus and calcium-phosphorus product in haemodialysis patients. METHODS: Dialysis patients with secondary hyperparathyroidism [parathyroid hormone (PTH) level > or =300 pg/ml] who were enrolled in one of four phase 2 placebo-controlled studies were eligible to enroll in an open-label extension study in which all patients received cinacalcet. For this extension study, cinacalcet was initiated at 30 mg in all patients and the dose was escalated to a maximum of 180 mg once daily if PTH concentrations were >250 pg/ml. Use of concomitant vitamin D sterols and phosphate binders was not restricted. RESULTS: The analysis of all patients (n = 59) completing 100 weeks of cinacalcet treatment showed long-term control of PTH and calcium-phosphorus product. Approximately 55% achieved a PTH concentration < or =300 pg/ml at the week-100 study visit, and approximately 60% had at least a 30% reduction in PTH from baseline. Serum calcium, phosphorus and the calcium-phosphorus product did not increase during the study. Concomitant vitamin D sterol and phosphate binder therapy remained stable. Cinacalcet was safe and generally well tolerated at doses up to 180 mg/day. CONCLUSIONS: In this long-term study, cinacalcet effectively sustained reductions in PTH for up to 3 years without increasing concentrations of serum calcium, phosphorus or calcium-phosphorus product.

Cinacalcet for secondary hyperparathyroidism in patients receiving hemodialysis.

BACKGROUND: Treatment of secondary hyperparathyroidism with vitamin D and calcium in patients receiving dialysis is often complicated by hypercalcemia and hyperphosphatemia, which may contribute to cardiovascular disease and adverse clinical outcomes. Calcimimetics target the calcium-sensing receptor and lower parathyroid hormone levels without increasing calcium and phosphorus levels. We report the results of two identical randomized, double-blind, placebo-controlled trials evaluating the safety and effectiveness of the calcimimetic agent cinacalcet hydrochloride. METHODS: Patients who were receiving hemodialysis and who had inadequately controlled secondary hyperparathyroidism despite standard treatment were randomly assigned to receive cinacalcet (371 patients) or placebo (370 patients) for 26 weeks. Once-daily doses were increased from 30 mg to 180 mg to achieve intact parathyroid hormone levels of 250 pg per milliliter or less. The primary end point was the percentage of patients with values in this range during a 14-week efficacy-assessment phase. RESULTS: Forty-three percent of the cinacalcet group reached the primary end point, as compared with 5 percent of the placebo group (P<0.001). Overall, mean parathyroid hormone values decreased 43 percent in those receiving cinacalcet but increased 9 percent in the placebo group (P<0.001). The serum calcium-phosphorus product declined by 15 percent in the cinacalcet group and remained unchanged in the placebo group (P<0.001). Cinacalcet effectively reduced parathyroid hormone levels independently of disease severity or changes in vitamin D sterol dose. CONCLUSIONS: Cinacalcet lowers parathyroid hormone levels and improves calcium-phosphorus homeostasis in patients receiving hemodialysis who have uncontrolled secondary hyperparathyroidism.