Effect of Etelcalcetide vs Placebo on Serum Parathyroid Hormone in Patients Receiving Hemodialysis With Secondary Hyperparathyroidism: Two Randomized Clinical Trials.

Importance: Secondary hyperparathyroidism contributes to extraskeletal complications in chronic kidney disease. Objective: To evaluate the effect of the intravenous calcimimetic etelcalcetide on serum parathyroid hormone (PTH) concentrations in patients receiving hemodialysis. Design, Setting, and Participants: Two parallel, phase 3, randomized, placebo-controlled treatment trials were conducted in 1023 patients receiving hemodialysis with moderate to severe secondary hyperparathyroidism. Trial A was conducted in 508 patients at 111 sites in the United States, Canada, Europe, Israel, Russia, and Australia from March 12, 2013, to June 12, 2014; trial B was conducted in 515 patients at 97 sites in the same countries from March 12, 2013, to May 12, 2014. Interventions: Intravenous administration of etelcalcetide (n = 503) or placebo (n = 513) after each hemodialysis session for 26 weeks. Main Outcomes and Measures: The primary efficacy end point was the proportion of patients achieving greater than 30% reduction from baseline in mean PTH during weeks 20-27. A secondary efficacy end point was the proportion of patients achieving mean PTH of 300 pg/mL or lower. Results: The mean age of the 1023 patients was 58.2 (SD, 14.4) years and 60.4% were men. Mean PTH concentrations at baseline and during weeks 20-27 were 849 and 384 pg/mL vs 820 and 897 pg/mL in the etelcalcetide and placebo groups, respectively, in trial A; corresponding values were 845 and 363 pg/mL vs 852 and 960 pg/mL in trial B. Patients randomized to etelcalcetide were significantly more likely to achieve the primary efficacy end point: in trial A, 188 of 254 (74.0%) vs 21 of 254 (8.3%; P < .001), for a difference in proportions of 65.7% (95% CI, 59.4%-72.1%) and in trial B, 192 of 255 (75.3%) vs 25 of 260 (9.6%; P < .001), for a difference in proportions of 65.7% (95% CI, 59.3%-72.1%). Patients randomized to etelcalcetide were significantly more likely to achieve a PTH level of 300 pg/mL or lower: in trial A, 126 of 254 (49.6%) vs 13 of 254 (5.1%; P < .001), for a difference in proportions of 44.5% (95% CI, 37.8%-51.2%) and in trial B, 136 of 255 (53.3%) vs 12 of 260 (4.6%; P < .001), for a difference in proportions of 48.7% (95% CI, 42.1%-55.4%). In trials A and B, respectively, patients receiving etelcalcetide had more muscle spasms (12.0% and 11.1% vs 7.1% and 6.2% with placebo), nausea (12.4% and 9.1% vs 5.1% and 7.3%), and vomiting (10.4% and 7.5% vs 7.1% and 3.1%). Conclusions and Relevance: Among patients receiving hemodialysis with moderate to severe secondary hyperparathyroidism, use of etelcalcetide compared with placebo resulted in greater reduction in serum PTH over 26 weeks. Further studies are needed to assess clinical outcomes as well as longer-term efficacy and safety. Trial Registration: clinicaltrials.gov Identifiers: NCT01788046.

Treatment of Secondary Hyperparathyroidism: Results of a Phase 2 Trial Evaluating an Intravenous Peptide Agonist of the Calcium-Sensing Receptor.

BACKGROUND/AIMS: This study evaluated the efficacy and safety of AMG416 (etelcalcitide), a novel peptide agonist of the calcium (Ca)-sensing receptor given intravenously (IV) after each hemodialysis session for the treatment of secondary hyperparathyroidism (SHPT). METHODS: Adult subjects with SHPT on hemodialysis enrolled in a 12-week, dose titration (parent) study followed by an open-label extension phase. AMG416 was administered IV, thrice weekly starting at 5 mg/session and titrated based on the subject's parathyroid hormone (PTH) and albumin-corrected Ca (cCa) to target a PTH of 150-300 pg/ml. Efficacy (percent PTH change from baseline to the efficacy analysis period during the parent study) and safety (open-label extension phase) endpoints were evaluated. RESULTS: Baseline (n = 37) mean (standard error [SE]) PTH was 853 (106 pg/ml). The mean (95% CI) percent change from baseline to the efficacy analysis period in PTH concentration was -53.6% (-60.8, -46.4). The proportion of subjects with ≥30% reduction in PTH from baseline to the efficacy assessment period (EAP) was 89% (32/36; 95% CI 73.9, 96.9). Results by the baseline PTH subgroup (≤700 vs. >700 pg/ml) were comparable for both analyses. The proportion of subjects achieving a PTH ≤300 pg/ml was 56% (n = 20/36) at the efficacy assessment period. The mean (SE) percent changes from baseline to EAP were observed for cCa -15% (1.0%) and phosphorus -10% (3.3%). Adverse events were mild to moderate in severity. The PTH reductions achieved in the parent study were maintained in the open-label extension phase. CONCLUSION: AMG416 was well tolerated and appears to be an effective agent for the treatment of SHPT in patients on hemodialysis.

Effect of cinacalcet on cardiovascular disease in patients undergoing dialysis.

BACKGROUND: Disorders of mineral metabolism, including secondary hyperparathyroidism, are thought to contribute to extraskeletal (including vascular) calcification among patients with chronic kidney disease. It has been hypothesized that treatment with the calcimimetic agent cinacalcet might reduce the risk of death or nonfatal cardiovascular events in such patients. METHODS: In this clinical trial, we randomly assigned 3883 patients with moderate-to-severe secondary hyperparathyroidism (median level of intact parathyroid hormone, 693 pg per milliliter [10th to 90th percentile, 363 to 1694]) who were undergoing hemodialysis to receive either cinacalcet or placebo. All patients were eligible to receive conventional therapy, including phosphate binders, vitamin D sterols, or both. The patients were followed for up to 64 months. The primary composite end point was the time until death, myocardial infarction, hospitalization for unstable angina, heart failure, or a peripheral vascular event. The primary analysis was performed on the basis of the intention-to-treat principle. RESULTS: The median duration of study-drug exposure was 21.2 months in the cinacalcet group, versus 17.5 months in the placebo group. The primary composite end point was reached in 938 of 1948 patients (48.2%) in the cinacalcet group and 952 of 1935 patients (49.2%) in the placebo group (relative hazard in the cinacalcet group vs. the placebo group, 0.93; 95% confidence interval, 0.85 to 1.02; P=0.11). Hypocalcemia and gastrointestinal adverse events were significantly more frequent in patients receiving cinacalcet. CONCLUSIONS: In an unadjusted intention-to-treat analysis, cinacalcet did not significantly reduce the risk of death or major cardiovascular events in patients with moderate-to-severe secondary hyperparathyroidism who were undergoing dialysis. (Funded by Amgen; EVOLVE ClinicalTrials.gov number, NCT00345839.).

A randomized, double-blind, placebo-controlled study to assess the efficacy and safety of cinacalcet HCl in participants with CKD not receiving dialysis.

BACKGROUND: Secondary hyperparathyroidism is observed in patients with early chronic kidney disease (CKD). This study investigated the safety and efficacy of cinacalcet for secondary hyperparathyroidism in participants with CKD not receiving dialysis. STUDY DESIGN: Double-blind, randomized, 32-week, phase 3 study. SETTING & PARTICIPANTS: 404 participants with stage 3 or 4 CKD from 73 centers in 9 countries. INTERVENTIONS: Cinacalcet:placebo (3:1 ratio). OUTCOMES & MEASUREMENTS: Proportion of participants with a mean decrease of 30% or greater in intact parathyroid hormone (iPTH) level, proportion with iPTH level of 70 or less or 110 or less pg/mL (stage 3 and 4 CKD, respectively), and mean percentage of iPTH change from baseline, all during the efficacy-assessment phase. RESULTS: A greater proportion of cinacalcet than placebo participants achieved a 30% or greater decrease in iPTH level (74% versus 28%; P < 0.001), corresponding to a 43.1% decrease in iPTH level from baseline (cinacalcet) compared with a 1.1% increase (placebo). At week 32, serum calcium levels were 8.9 +/- 0.8 mg/dL (-8.9%; cinacalcet) and 9.9 +/- 0.6 mg/dL (+0.8%; placebo), phosphorus levels were 4.5 +/- 1.0 mg/dL (+21.4%) and 4.0 +/- 0.7 mg/dL (+6.8%), and calcium-phosphorus product values were 40.1 +/- 8.3 mg(2)/dL(2) (+18.9%) and 38.9 +/- 6.9 mg(2)/dL(2) (+17.1%), respectively. During the study course, 62% (cinacalcet) and 1% (placebo) of participants experienced 2 consecutive serum calcium concentrations less than 8.4 mg/dL. They generally were asymptomatic and without significant clinical consequences. Treatment generally was well tolerated, and most adverse events were mild to moderate in severity. LIMITATIONS: The study was not designed to assess the effects of cinacalcet on vascular calcification, bone histomorphometric parameters, or other clinical outcomes. It is not known whether the observed differences in changes in iPTH levels are clinically more important than observed differences in changes in serum calcium or phosphorus levels or dosages of vitamin D sterols and phosphate binders. CONCLUSIONS: These data show that cinacalcet treatment in patients with CKD not receiving dialysis can decrease plasma iPTH levels, but with frequent (albeit generally asymptomatic) serum calcium levels less than 8.4 mg/dL and increases in serum phosphorus levels.

Rationale--Trial to Reduce Cardiovascular Events with Aranesp Therapy (TREAT): evolving the management of cardiovascular risk in patients with chronic kidney disease.

BACKGROUND: Patients with chronic kidney disease (CKD) have a high burden of mortality and cardiovascular morbidity. Additional strategies to modulate cardiovascular risk in this population are needed. Data suggest that anemia is a potent and potentially modifiable risk factor for cardiovascular disease in patients with CKD, but these data remain unsubstantiated by any randomized controlled trial (RCT). Furthermore, the clinical practice guidelines for anemia management in patients with CKD are based on limited data. The need for new RCTs to address critical knowledge deficits, particularly with regard to the impact of anemia therapy on cardiovascular disease and survival, is recognized within the guidelines and independent comprehensive reviews of the existing published trial data. STUDY DESIGN: The Trial to Reduce Cardiovascular Events with Aranesp (Amgen Inc, Thousand Oaks, Calif) (darbepoetin alfa) Therapy (TREAT) is a 4000-patient, multicenter, double-blind RCT, designed to determine the impact of anemia therapy with darbepoetin alfa on mortality and nonfatal cardiovascular events in patients with CKD and type 2 diabetes mellitus. Subjects will be randomized in a 1:1 manner to either darbepoetin alfa therapy to a target hemoglobin (Hb) of 13 g/dL or control, consisting of placebo for Hb > or =9 g/dL or darbepoetin alfa for Hb <9 g/dL until Hb is again Hb > or =9 g/dL. TREAT is event-driven and has a composite primary end point comprising time to mortality and nonfatal cardiovascular events, including myocardial infarction, myocardial ischemia, stroke, and heart failure. TREAT will provide data that are critical to evolution of the management of cardiovascular risk in this high-risk population.

Anemia: a continuing problem following kidney transplantation.

Cardiovascular disease is a leading cause of death among kidney transplant recipients. Anemia, a risk factor for cardiovascular complications among patients with chronic kidney disease, has not been well characterized in kidney transplant recipients. We performed a retrospective cohort study of the prevalence of and factors associated with anemia among 240 patients who underwent kidney transplantation at our institution. The mean hematocrit (Hct) rose from 33% at 1 month after transplantation to 40% at 12 months after transplantation. The proportion of patients with Hct < 36% was 76% at transplantation and 21% and 36%, 1 year and 4 years after transplantation, respectively. Six months after transplantation, women had higher likelihood (OR = 3.61) of Hct < 36%, while higher Hct at 3 months (OR = 0.67 for 1% higher Hct) and diabetes (OR = 0.14) were associated with a lower likelihood of Hct < 36%. Similar associations were seen 12 months after transplantation. Even among patients with Hct < 30%, only 36% had iron studies, 46% received iron supplementation and 40% received recombinant human erythropoietin. Awareness of factors associated with a lower Hct may prompt better anemia screening and management, potentially improving cardiovascular outcomes among kidney transplant recipients.

Hospitalization during advancing chronic kidney disease.

BACKGROUND: The care of patients with end-stage renal disease (ESRD) is associated with substantial costs to society, much of which is accounted for by a high rate of hospitalization. However, the influence of declining kidney function on hospitalization as ESRD approaches is not well understood. METHODS: We performed a retrospective cohort study of national data to evaluate the frequency of hospitalizations among patients with chronic kidney disease (CKD) who reached ESRD and had at least 2 years of Medicare eligibility before initiation of dialysis therapy. The study period for each patient extended from 2 years before to 6 months after the initiation of dialysis therapy. RESULTS: The study cohort was composed of 109,321 patients with a mean age of 75 years, all of whom initiated long-term dialysis therapy between 1995 and 1998. Mean hospitalization rate was 134 hospitalizations/1,000 patient-months at risk (PMAR). Hospitalization rates gradually increased as ESRD approached, peaking in the 3 months immediately after the initiation of dialysis therapy at 487 hospitalizations/1,000 PMAR. Cause-specific hospitalization rates mirrored this trend and were greatest for placement of vascular access and diagnoses related to cardiovascular (CVD) and infectious disease. CONCLUSION: Hospitalizations during CKD become more frequent with the approach of ESRD. The majority of these hospitalizations, both before and after the initiation of dialysis therapy, are caused by comorbidity related to CKD. These hospitalizations may be favorably impacted on by heightened attention to the prevention and management of CVD and timely placement of vascular access during CKD.