[Cholecalciferol supplementation improves secondary hyperparathyroidism control in hemodialysis patients].

Introduction: Vitamin D deficiency is common among hemodialysis (HD) patients and is an important component in the pathogenesis of secondary hyperparathyroidism (SHPT). We herein report our experience on the impact of cholecalciferol supplementation on PTH levels in a group of HD patients. Patients and methods: We selected 122 HD patients. The main selection criteria were 25- hydroxyvitamin D (25(OH)D) levels ≤30 ng/mL and SHPT defined as PTH levels >300 pg/mL or PTH levels between 150-300 pg/mL during therapy with cinacalcet or paricalcitol. 82 patients agreed to receive cholecalciferol at the fixed dose of 25,000 IU per week orally for 12 months, while the remaining 40 represented the control group. The main endopoints of the study were the reduction in PTH levels ≥30% compared to baseline values and the increase of 25(OH)D levels to values >30 ng/mL. Results: At follow-up PTH levels decreased in the supplemented group from 476 ±293 to 296 ± 207 pg/mL (p<0.001), 25(OH)D levels increased from 10.3 ± 5.7 to 33.5 ± 11.2 ng/mL (p<0.001), serum calcium increased from 8.6 ± 0.5 to 8.8 ± 0.6 mg/dL (p<0.05) while serum phosphorus did not change. In this group the mean doses of paricalcitol were significantly reduced, from 8.7 ± 4.0 to 6.1 ± 3.9 µg/week (p<0.001). Moreover, in this group there were a significant increase of hemoglobin levels, from 11.6 ± 1.3 to 12.2 ± 1.1 g/dL (p <0.01) and a significant reduction of erythropoietin doses (p<0.05). In the control group the 25(OH)D and PTH levels did not change, while cinacalcet doses increased from 21 ±14 to 43 ± 17 mg/d (p<0.01). Conclusions: Vitamin deficiency is very common in HD patients. Cholecalciferol treatment significantly increased serum 25(OH)D levels, significantly decreased PTH levels and paricalcitol doses, concurrently entailing a better control of anemia.

Cinacalcet studies in pediatric subjects with secondary hyperparathyroidism receiving dialysis.

BACKGROUND: Secondary hyperparathyroidism (sHPT), a complication of chronic kidney disease (CKD) characterized by persistently elevated parathyroid hormone (PTH), alterations in calcium-phosphorus homeostasis, and vitamin D metabolism, affects 50% of children receiving dialysis. A significant proportion of these children develop CKD-mineral and bone disorder (CKD-MBD), associated with an increased risk of fractures and vascular calcification. The standard of care for sHPT in children includes vitamin D sterols, calcium supplementation, and phosphate binders. Several agents are approved for sHPT treatment in adults undergoing dialysis, including vitamin D analogs and calcimimetics, with limited information on their safety and efficacy in children. The calcimimetic cinacalcet is approved for use in adults with sHPT on dialysis, but is not approved for pediatric use outside Europe. METHODS: This review provides dosing, safety, and efficacy information from Amgen-sponsored cinacalcet pediatric trials and data from non-Amgen sponsored clinical studies. RESULTS: The Amgen cinacalcet pediatric clinical development program consisted of two Phase 3 randomized studies, one Phase 3 single arm extension study, one open-label Phase 2 study, and two open-label Phase 1 studies. Effects of cinacalcet on PTH varied across studies. Overall, 7.4 to 57.1% of subjects who received cinacalcet in an Amgen clinical trial attained PTH levels within recommended target ranges and 22.2 to 70.6% observed a ≥ 30% reduction in PTH. In addition, significant reductions in PTH were demonstrated in all non-Amgen-supported studies. CONCLUSIONS: To help inform the pediatric nephrology community, this manuscript contains the most comprehensive review of cinacalcet usage in pediatric CKD patients to date.

Effectiveness of cinacalcet treatment for secondary hyperparathyroidism on hospitalization: Results from the MBD-5D study.

OBJECTIVES: To elucidate the effect of cinacalcet use on all-cause and cause-specific hospitalization outcomes using a prospective cohort of maintenance hemodialysis patients. METHODS: We used data from a prospective cohort of Japanese hemodialysis patients with secondary hyperparathyroidism and examined baseline characteristics as well as longitudinal changes. All patients were cinacalcet-naïve at study enrollment. Further, we used a marginal structural model to account for time-varying confounders on cinacalcet initiation and hospitalization outcomes, and an Andersen-Gill-type recurrent event model to account for any recurring events of hospitalization in the outcome analysis using the weighted dataset. RESULTS: Among the 3,276 patients, cinacalcet treatment was initiated in 1,384 patients during the entire follow-up. Cinacalcet users were slightly younger, included more patients with chronic glomerulonephritis and fewer patients with diabetes, were more likely to have a history of parathyroidectomy, and were more often used receiving vitamin D receptor activator, phosphate binders, and iron supplements. The overall hospitalization analysis yielded a hazard ratio (HR) of 0.97 (95% confidence interval [CI]: 0.80, 1.18). A trend toward a mild protective association was observed for cardiovascular-related hospitalizations (HR: 0.85; 95% CI: 0.64, 1.14). In the subgroup analysis, a protective association was seen due to cinacalcet use for infection-related hospitalizations in the lowest intact parathyroid hormone group (HR: 0.36; 95% CI: 0.14, 0.95). CONCLUSIONS: Cinacalcet initiation in patients on maintenance hemodialysis had no effect on all-cause and cause-specific hospitalizations. Although the overall association was statistically not significant, cinacalcet may have a protective association on cardiovascular-related hospitalization in all patients and infection-related hospitalization in patient with low intact parathyroid hormone.

[Effect of cinacalcet combined with low-dose calcitriol on clinical outcome and bone metabolism in patients with severe secondary hyperparathyroidism].

OBJECTIVE: To observe the clinical outcome and the effect of the combination of cinacalcet hydrochloride with low-dose calcitriol on bone metabolism in maintenance hemodialysis (MHD) patients with severe secondary hyperparathyroidism (SHPT).
 Methods: Thirty SHPT patients were enrolled to receive treatment of cinacalcet combined with low-dose calcitriol, with inclusion criteria as follows: maintenance on MHD>6 months; serum intact parathyroid hormone (iPTH)>600 pg/mL; parathyroid glands with more than 1 nodules by ultrasonography; traditional therapy with no effects. All patients were given cinacalcet 25-75 mg and 0.5 µg calcitriol daily. Serum Ca, P, iPTH, bone metabolic markers and bone density were measured before and after treatment. The clinical symptoms and their changes were recorded.
 Results: The baseline levels of iPTH, Ca and P were (1787.3±1 321.0) pg/mL, (2.54±0.19) mmol/L, and (2.06±0.15) mmol/L, respectively. After 2 weeks of treatment, serum phosphorus decreased by 20%; after 1 and 3 months of treatment, iPTH decreased by 35% and 70%. Ca and P fell to (2.39±0.17) and (1.56±0.50) mmol/L (P<0.05), respectively. The symptoms of the patients relieved. The above indicators remained stable after 12 months. Moreover, after 6 months of treatment, the alkaline phosphatase, osteocalcin and ß-cross levels were decreased by 50%, 37% and 49%, respectively. The decline in patients' bone density was inhibited. No severe adverse events were observed.
 Conclusion: Cinacalcet hydrochloride combined with low dose calcitriol can improve high calcium, high phosphorus and high iPTH in MHD patients with severe SHPT, relieve symptoms, and improve bone metabolism. It can be used as a favorable choice for the treatment of SHPT.

The association between cinacalcet use and missed in-center hemodialysis treatment rate.

PURPOSE: Missed in-center hemodialysis treatments (MHT) are a general indicator of health status in hemodialysis patients. This analysis was conducted to estimate the association between cinacalcet use and MHT rate. METHODS: We studied patients receiving hemodialysis and prescription benefits services from a large dialysis organization. Incident cinacalcet users were propensity score matched to controls on 31 demographic, clinical, and laboratory variables. We applied inverse probability (IP) of censoring and crossover weights to account for informative censoring. Weighted negative binomial modeling was used to estimate MHT rates and pooled logistics models were used to estimate the association between cinacalcet use and MHT. RESULTS: Baseline demographic and clinical variables included serum calcium, phosphorus, parathyroid hormone, and vitamin D use, and were balanced between 15,474 new cinacalcet users and 15,474 matched controls. In an analysis based on intention-to-treat principles, 40.8% of cinacalcet users and 46.5% of nonusers were censored. MHT rate was 13% lower among cinacalcet initiators versus controls: IP of censoring weighted incidence rate ratio was 0.87 (95% confidence interval [CI]: 0.84-0.90 p < 0.001). In analyses based on as-treated principles, 72.8% and 61.5% of cinacalcet users and nonusers, respectively, crossed over or were censored. MHT rate was 15% lower among cinacalcet initiators versus controls: IP of censoring/crossover weighted incidence rate ratio was 0.85 (95%CI: 0.82-0.87 p < 0.001). CONCLUSIONS: After controlling for indication and differential censoring, cinacalcet treatment was associated with lower MHT rates, which may reflect better health status. Copyright © 2016 John Wiley & Sons, Ltd.

Pharmacokinetic and Pharmacodynamic Properties of Cinacalcet (KRN1493) in Chinese Healthy Volunteers: A Randomized, Open-label, Single Ascending-dose and Multiple-dose, Parallel-group Study.

PURPOSE: The aim of this study was to assess the pharmacokinetic (PK) and pharmacodynamic (PD) properties and safety of single and multiple doses of cinacalcet in Chinese healthy volunteers (HVs) for the purposes of a New Drug Application package for the Chinese Food and Drug Administration. METHODS: In this randomized, open-label, single ascending-dose and multiple-dose, parallel-group study, 42 Chinese HVs were randomized to receive a single oral dose of 25, 50, or 100 mg of cinacalcet and multiple doses of 50 mg of cinacalcet once daily for 7 days. Plasma cinacalcet concentrations were analyzed by HPLC-MS/MS. The PK parameters were assessed with noncompartmental analysis. Plasma intact parathyroid hormone, serum calcium, and phosphorus concentrations were measured for PD evaluation. The safety profile was also assessed. Adverse events (AEs) were noted during the study. FINDINGS: Of the 42 randomized HVs, 41 completed the study per protocol; 1 prematurely discontinued the study because of AEs. Cinacalcet has nonlinear PK properties over a dose range of 25 to 100 mg after a single dose. Mean (SD) Cmax values were 7.68 (4.25), 17 (6.33), and 31.3 (16.42) ng/mL with single doses of 25, 50, and 100 mg of cinacalcet, respectively. Mean (SD) AUC0- last values were 58.4 (25.38), 187 (70.7), and 367 (180.03) hr∙ng/mL with single doses of 25, 50, and 100 mg of cinacalcet, respectively. Steady state was attained within 7 doses of successive daily administration of 50 mg of cinacalcet. At steady state, the mean (SD) Cmax and AUC0-last values were 20.6 (9.63) ng/mL and 297 (146.15) ng∙h/mL. The accumulation ratios of Cmax and AUC (AUCτ/AUC0-24) were 1.21 and 1.32. Plasma intact parathyroid hormone and serum calcium concentrations had similar patterns, both decreased after administration of cinacalcet, whether after single dose or multiple doses. A total of 52 AEs were reported in 20 HVs (47.6%). The most frequently reported AEs after single-dose and multiple-dose cinacalcet administration were hypocalcemia, numbness, dizziness, and muscle soreness. No serious AEs were reported. IMPLICATIONS: Cinacalcet was well tolerated and effective after administration of a single oral dose up to 100 mg and multiple doses of 50 mg of cinacalcet once daily for 7 days. Cinacalcet has nonlinear PK properties over a dose range of 25 to 100 mg after a single dose. PK profiles after multiple doses were similar to those after a single dose with no accumulation. Cinacalcet had similar PK and safety profiles between Chinese and Western HVs at the same dose levels.

Administration of calcimimetics after dialysis: same effectiveness, better gastrointestinal tolerability.

INTRODUCTION: Cinacalcet has proved effective to control secondary hyperparathyroidism in patients on haemodialysis (HD). Some studies have reported an appropriate secondary hyperparathyroidism control and a better compliance after intradialytic use of calcimimetics. OBJECTIVES: To assess the effect of post-dialysis calcimimetics use on mineral bone disorders and calcimimetics gastrointestinal tolerability in our HD unit. MATERIAL AND METHODS: A 12-week single-centre prospective study in HD patients treated with cinacalcet (>2 months). Two study periods: Usual outpatient use (Stage 1) and use after HD session (Stage 2). ENDPOINTS: 1) Biochemical MBD data; 2) Gastrointestinal Symptom Rating Scale (GSRS) for gastrointestinal tolerability, and visual analogic scale (VAS) for satisfaction; 3) Adherence: Morisky-Green test (MG) and final tablet count (TC). RESULTS: Sixty-two HD patients. Fourteen received cinacalcet (22.5%). TEN patients were included, mean age was 60.9 years; patients had received HD for 80.9 months. Mean Charlson index: 9. Biochemical data: Stage 1 (initial vs. final): Ca 8.8 ± 0.5 vs. 9.1 ± 0.7 mg/dl (p<0.05); P 5.2 ± 0.8 vs. 4.5 ± 1.6 mg/dl, iPTH 360.3 ± 232.7 vs. 349 ± 122 pg/ml. MG: 70%. Stage 2 (initial vs. final): Ca 9.1 ± 0.7 vs. 8.8 ± 0.6 mg/dl; P 4.5 ± 1.6 vs. 4.6 ± 1.3 mg/dl, iPTH 360.3 ± 232.7 vs. 349 ± 122 pg/ml. TC: 89%. GSRS and VAS were better in Stage 2 (GSRS 7.5 ± 5.2 vs. 4.3 ± 1.9; VAS 4.8 ± 2.3 vs. 6.9 ± 2.8). No significant changes were observed in calcimimetic dose (201 vs. 207 mg/wk), number of phosphate binders (9 vs. 8.2 pts/day), native vitamin D (70 vs. 60%), selective vit D receptor activators (30%), or suitable dialysis parameters. CONCLUSIONS: Post-dialysis use of calcimimetic was effective in secondary hyperparathyroidism control, improved gastrointestinal tolerability and ameliorated patients' satisfaction. Based on our findings, post-dialysis use of calcimimetics should be considered in selected patients with low therapeutic compliance.

Propensity score matching and persistence correction to reduce bias in comparative effectiveness: the effect of cinacalcet use on all-cause mortality.

PURPOSE: The generalisability of randomised controlled trials (RCTs) may be limited by restrictive entry criteria or by their experimental nature. Observational research can provide complementary findings but is prone to bias. Employing propensity score matching, to reduce such bias, we compared the real-life effect of cinacalcet use on all-cause mortality (ACM) with findings from the Evaluation of Cinacalcet Therapy to Lower Cardiovascular Events (EVOLVE) RCT in chronic haemodialysis patients. METHODS: Incident adult haemodialysis patients receiving cinacalcet, recruited in a prospective observational cohort from 2007-2009 (AROii; n = 10,488), were matched to non-exposed patients regardless of future exposure status. The effect of treatment crossover was investigated with inverse probability of censoring weighted and lag-censored analyses. EVOLVE ACM data were analysed largely as described for the primary composite endpoint. RESULTS: AROii patients receiving cinacalcet (n = 532) were matched to 1790 non-exposed patients. The treatment effect of cinacalcet on ACM in the main AROii analysis (hazard ratio 1.03 [95% confidence interval (CI) 0.78-1.35]) was closer to the null than for the Intention to Treat (ITT) analysis of EVOLVE (0.94 [95%CI 0.85-1.04]). Adjusting for non-persistence by 0- and 6-month lag-censoring and by inverse probability of censoring weight, the hazard ratios in AROii (0.76 [95%CI 0.51-1.15], 0.84 [95%CI 0.60-1.18] and 0.79 [95%CI 0.56-1.11], respectively) were comparable with those of EVOLVE (0.82 [95%CI 0.67-1.01], 0.83 [95%CI 0.73-0.96] and 0.87 [95%CI 0.71-1.06], respectively). CONCLUSIONS: Correcting for treatment crossover, we observed results in the 'real-life' setting of the AROii observational cohort that closely mirrored the results of the EVOLVE RCT. Persistence-corrected analyses revealed a trend towards reduced ACM in haemodialysis patients receiving cinacalcet therapy.

[Medical treatment of children with hypophosphataemic rickets]. / Medicinsk behandling af hypofosfatæmisk rakitis hos børn.

Hypophosphataemic rickets is a rare, genetic disorder resulting in defect bone mineralisation and rickets. The current medical treatment consists of phosphate supplementation and alfacalcidol, but side effects such as secondary hyperparat-hyroidism and nephrocalcinosis are common. This treatment regimen often fails to prevent bone deformity and reduced final height. The rarity and complexity of these diseases call for centralised specialist care and international collaboration. Future medical treatment may be improved by addition of new promising experimental treatments.