Effects of etelcalcetide on fibroblast growth factor 23 in patients with secondary hyperparathyroidism receiving hemodialysis

Background: Etelcalcetide is an intravenous calcimimetic approved for treatment of secondary hyperparathyroidism (sHPT) in patients receiving hemodialysis. Besides lowering parathyroid hormone (PTH), etelcalcetide also significantly reduces fibroblast growth factor 23 (FGF23), but the mechanisms are unknown. Methods: To investigate potential mediators of etelcalcetide-induced FGF23 reduction, we performed secondary analyses of the 26-week randomized trials that compared the effects on PTH of etelcalcetide (n = 509) versus placebo (n = 514) and etelcalcetide (n = 340) versus cinacalcet (n = 343) in adults with sHPT receiving hemodialysis. We analyzed changes in FGF23 in relation to changes in PTH, calcium, phosphate and bone turnover markers. We also investigated how concomitant treatments aimed at mitigating hypocalcemia altered the FGF23-lowering effects of etelcalcetide. Results: Etelcalcetide reduced FGF23 [median % change (quartile 1-quartile 3)] from baseline to the end of the trial significantly more than placebo [-56% (-85 to -7) versus +2% (-40 to +65); P < 0.001] and cinacalcet [-68% (-87 to -26) versus -41% (-76 to +25); P < 0.001]. Reductions in FGF23 correlated strongly with reductions in calcium and phosphate, but not with PTH; correlations with bone turnover markers were inconsistent and of borderline significance. Increases in concomitant vitamin D administration partially attenuated the FGF23-lowering effect of etelcalcetide, but increased dialysate calcium concentration versus no increase and increased dose of calcium supplementation versus no increase did not attenuate the FGF23-lowering effects of etelcalcetide. Conclusion: These data suggest that etelcalcetide potently lowers FGF23 in patients with sHPT receiving hemodialysis and that the effect remains detectable among patients who receive concomitant treatments aimed at mitigating treatment-associated decreases in serum calcium

Patterns of Hemodialysis Catheter Dysfunction Defined According to National Kidney Foundation Guidelines As Blood Flow <300 mL/min

Blood flow rate (BFR) <300 mL/min commonly is used to define hemodialysis catheter dysfunction and the need for interventions to prevent complications. The objective of this study was to describe patterns of unplanned BFR <300 mL/min during catheter hemodialysis using data from DaVita dialysis facilities and the United States Renal Data System. Patients were included if they received at least eight weeks of hemodialysis exclusively through a catheter between 08/04 and 12/06, and catheter hemodialysis was the first treatment modality following diagnosis of end-stage renal disease (first access), or it immediately followed at least one 30-day period of dialysis exclusively through a fistula or graft (replacement access). Actual BFR <300 mL/min despite a planned BFR ≥300 mL/min defined catheter dysfunction during each dialysis session. There were 3,364 patients, 268,363 catheter dialysis sessions, and 19,118 (7.1%) sessions with catheter dysfunction. Almost two-thirds of patients had ≥1 catheter dysfunction session, and 30% had ≥1 catheter dysfunction session per month. Patients with catheter as a replacement access had a higher rate of catheter dysfunction than those with a catheter as first access (hazard ratio: 1.13; P = 0.04). Catheter dysfunction affects almost one-third of catheter dialysis patients each month and two-thirds overall

Impact of Hemodialysis Catheter Dysfunction on Dialysis and Other Medical Services: An Observational Cohort Study

Practice guidelines define hemodialysis catheter dysfunction as blood flow rate (BFR) <300 mL/min. We conducted a study using data from DaVita and the United States Renal Data System to evaluate the impact of catheter dysfunction on dialysis and other medical services. Patients were included if they had ≥8 consecutive weeks of catheter dialysis between 8/2004 and 12/2006. Actual BFR <300 mL/min despite planned BFR ≥300 mL/min was used to define catheter dysfunction during each dialysis session. Among 9,707 patients, the average age was 62,53% were female, and 40% were black. The median duration of catheter dialysis was 190 days, and the cohort accounted for 1,075,701 catheter dialysis sessions. There were 70,361 sessions with catheter dysfunction, and 6,33 1 (65.2%) patients had at least one session with catheter dysfunction. In multivariate repeated measures analysis, catheter dysfunction was associated with increased odds of missing a dialysis session due to access problems (Odds ratio [OR] 2.50; P < 0.001), having an access-related procedure (OR 2.10; P < 0.001), and being hospitalized (OR 1.10; P = 0.001). Catheter dysfunction defined according to NKF vascular access guidelines results in disruptions of dialysis treatment and increased use of other medical services

Patiromer Decreases Serum Potassium and Phosphate Levels in Patients on Hemodialysis

Background: Persistent hyperkalemia (serum potassium (K) ≥5.5 mEq/l) is a common condition in hemodialysis (HD) patients, is associated with increased mortality, and treatment options are limited. The effect of patiromer, a gastrointestinal K binder, on serum K was examined in HD patients. Methods: Six hyperkalemic HD patients (5 anuric) were admitted to clinical research units for 15 days (1 pretreatment week and 1 patiromer treatment week) and they received a controlled diet with identical meals on corresponding days of pretreatment and treatment weeks. Phosphate (P) binders were discontinued on admission. Patiromer, 12.6 g daily (divided 4.2 g TID with meals), was started on the Monday morning following the last pretreatment week blood sampling. Serum and 24-hour stool samples were collected daily. Results: Mean ± SE serum K decreased (maximum change per corresponding day, 0.6 ± 0.2 mEq/l, p = 0.009) and fecal K increased 58% on patiromer compared with the pretreatment week. During the pretreatment week, 69.0, 47.6, and 11.9% of patients' serum K values were ≥5.5, ≥6.0, and ≥6.5 mEq/l, respectively. This was reduced to 38.1% (p = 0.009), 11.9% (p < 0.001), and 2.4% (p = 0.2) on patiromer. Following P binder discontinuation, the long interdialytic interval mean ± SE serum P numerically increased from 5.8 ± 0.4 to 7.0 ± 0.5 mg/dl (p = 0.06). On patiromer, P decreased from 7.0 ± 0.5 to 6.2 ± 0.5 mg/dl (p = 0.04). While on patiromer, fecal P numerically increased by 112 ± 72 mg/day (17%; p = 0.1792; range -148 to 344 mg/day). No patient discontinued patiromer because of adverse events (AEs); none had serious AEs. Conclusions: In 6 hyperkalemic HD patients, patiromer decreased serum K and P levels and increased fecal K

Differential effects of phosphate binders on vitamin D metabolism in chronic kidney disease.

BackgroundPhosphate binders are commonly used in the treatment of patients with hyperphosphatemia. While phosphate binders are used to lower phosphate, the effects of specific phosphate binder types on vitamin D metabolism are unknown.MethodsWe performed a secondary analysis of the Phosphate Normalization Trial in which patients with moderate to advanced chronic kidney disease were randomized to receive either placebo, sevelamer carbonate, lanthanum carbonate or calcium acetate for 9 months. We evaluated changes in serum concentrations of vitamin D metabolites including 24,25-dihydroxyvitamin D3 [24,25(OH)2D3], 1,25-dihydroxyvitamin D3 [1,25(OH)2D3], the ratio of 24,25(OH)2D3 to 25-hydroxyvitamin D [the vitamin D metabolite ratio (VMR)] and the ratio of serum 1,25(OH)2D to 25-hydroxyvitamin D.ResultsCompared with placebo, randomization to the calcium acetate arm was associated with a 0.6 ng/mL (95% CI 0.2, 1) and 13.5 pg/ng (95% CI 5.5, 21.5) increase in 24,25(OH)2D and VMR, respectively, and a 5.2 pg/mL (95% CI 1.1, 9.4) reduction in 1,25(OH)2D. Randomization to sevelamer carbonate was associated with a 0.5 ng/mL (95% CI -0.9, -0.1) and 11.8 pg/ng (95% CI -20, -3.5) reduction in 24,25(OH)2D3 and VMR, respectively. There was no association of the sevelamer arm with the change in 1,25(OH)2D3, and randomization to lanthanum carbonate was not associated with a change in any of the vitamin D metabolites.ConclusionAdministration of different phosphate binders to patients with moderate to severe CKD results in unique changes in vitamin D metabolism

Bardoxolone Methyl Improves Kidney Function in Patients with Chronic Kidney Disease Stage 4 and Type 2 Diabetes:Post-Hoc Analyses from Bardoxolone Methyl Evaluation in Patients with Chronic Kidney Disease and Type 2 Diabetes Study

Background: Increases in measured inulin clearance, measured creatinine clearance, and estimated glomerular filtration rate (eGFR) have been observed with bardoxolone methyl in 7 studies enrolling approximately 2,600 patients with type 2 diabetes (T2D) and chronic kidney disease (CKD). The largest of these studies was Bardoxolone Methyl Evaluation in Patients with Chronic Kidney Disease and Type 2 Diabetes (BEACON), a multinational, randomized, double-blind, placebo-controlled phase 3 trial which enrolled patients with T2D and CKD stage 4. The BEACON trial was terminated after preliminary analyses showed that patients randomized to bardoxolone methyl experienced significantly higher rates of heart failure events. We performed post-hoc analyses to characterize changes in kidney func-tion induced by bardoxolone methyl. Methods: Patients in -BEACON (n = 2,185) were randomized 1: 1 to receive oncedaily bardoxolone methyl (20 mg) or placebo. We compared the effects of bardoxolone methyl and placebo on a post-hoc composite renal endpoint consisting of = 30% decline from baseline in eGFR, eGFR <15 mL/min/1.73 m2, and end-stage renal disease (ESRD) events (provision of dialysis or kidney transplantation). Results: Consistent with prior studies, patients randomized to bardoxolone methyl experienced mean increases in eGFR that were sustained through study week 48. Moreover, increases in eGFR from baseline were sustained 4 weeks after cessation of treatment. Patients randomized to bardoxolone methyl were significantly less likely to experience the composite renal endpoint (hazards ratio 0.48 [95% CI 0.36-0.64]; p <0.0001). Conclusions: Bardoxolone methyl preserves kidney function and may delay the onset of ESRD in patients with T2D and stage 4 CKD. (C) 2018 The Author(s) Published by S. Karger AG, Base

Effect of Etelcalcetide vs Cinacalcet on Serum Parathyroid Hormone in Patients Receiving Hemodialysis With Secondary Hyperparathyroidism A Randomized Clinical Trial

Importance Secondary hyperparathyroidism contributes to extraskeletal calcification and is associated with all-cause and cardiovascular mortality. Control is suboptimal in the majority of patients receiving hemodialysis. An intravenously (IV) administered calcimimetic could improve adherence and reduce adverse gastrointestinal effects. Objective To evaluate the relative efficacy and safety of the IV calcimimetic etelcalcetide and the oral calcimimetic cinacalcet. Design, Setting, and Participants A randomized, double-blind, double-dummy active clinical trial was conducted comparing IV etelcalcetide vs oral placebo and oral cinacalcet vs IV placebo in 683 patients receiving hemodialysis with serum parathyroid hormone (PTH) concentrations higher than 500 pg/mL on active therapy at 164 sites in the United States, Canada, Europe, Russia, and New Zealand. Patients were enrolled from August 2013 to May 2014, with end of follow-up in January 2015. Interventions Etelcalcetide intravenously and oral placebo (n = 340) or oral cinacalcet and IV placebo (n = 343) for 26 weeks. The IV study drug was administered 3 times weekly with hemodialysis; the oral study drug was administered daily. Main Outcomes and Measures The primary efficacy end point was noninferiority of etelcalcetide at achieving more than a 30% reduction from baseline in mean predialysis PTH concentrations during weeks 20-27 (noninferiority margin, 12.0%). Secondary end points included superiority in achieving biochemical end points (>50% and >30% reduction in PTH) and self-reported nausea or vomiting. Results The mean (SD) age of the trial participants was 54.7 (14.1) years and 56.2% were men. Etelcalcetide was noninferior to cinacalcet on the primary end point. The estimated difference in proportions of patients achieving reduction in PTH concentrations of more than 30% between the 198 of 343 patients (57.7%) randomized to receive cinacalcet and the 232 of 340 patients (68.2%) randomized to receive etelcalcetide was −10.5% (95% CI, −17.5% to −3.5%, P for noninferiority, <.001; P for superiority, .004). One hundred seventy-eight patients (52.4%) randomized to etelcalcetide achieved more than 50% reduction in PTH concentrations compared with 138 patients (40.2%) randomized to cinacalcet (P = .001; difference in proportions, 12.2%; 95% CI, 4.7% to 19.5%). The most common adverse effect was decreased blood calcium (68.9% vs 59.8%). Conclusions and Relevance Among patients receiving hemodialysis with moderate to severe secondary hyperparathyroidism, the use of etelcalcetide was not inferior to cinacalcet in reducing serum PTH concentrations over 26 weeks; it also met superiority criteria. Further studies are needed to assess clinical outcomes as well as longer-term efficacy and safety

Effect of Etelcalcetide vs Placebo on Serum Parathyroid Hormone in Patients Receiving Hemodialysis With Secondary Hyperparathyroidism

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

Effects of bardoxolone methyl on body weight, waist circumference and glycemic control in obese patients with type 2 diabetes mellitus and stage 4 chronic kidney disease

AimsObesity is associated with progression of chronic kidney disease (CKD). Treatment with bardoxolone methyl in a multinational phase 3 trial, Bardoxolone Methyl Evaluation in Patients with Chronic Kidney Disease and Type 2 Diabetes (BEACON), resulted in increases in estimated glomerular filtration rate (eGFR) with concurrent reductions in body weight. We performed post-hoc analyses to further characterize reductions in body weight with bardoxolone methyl.MethodsEligible patients with type 2 diabetes (T2DM) and CKD stage 4 (eGFR 15 to &lt;30 mL/min/1.73 m2) were randomized 1:1 to receive once-daily oral dose of bardoxolone methyl (20 mg) or placebo.ResultsBEACON enrolled 2185 patients. Patients randomized to bardoxolone methyl experienced significant reductions in body weight from baseline relative to patients randomized to placebo (-5.7 kg; 95% CI: -6.0 to -5.3 kg; p &lt; 0.001). In patients randomized to bardoxolone methyl, rate and magnitude of body weight loss were proportional to baseline BMI. Bardoxolone methyl resulted in significant reductions in waist circumference and improved glycemic control.ConclusionsBardoxolone methyl resulted in significant weight loss in a generally obese patient population with T2DM and stage 4 CKD, with the magnitude and rate dependent on baseline BMI

Rapid Growth Reduces Cold Resistance: Evidence from Latitudinal Variation in Growth Rate, Cold Resistance and Stress Proteins

Background: Physiological costs of rapid growth may contribute to the observation that organisms typically grow at submaximal rates. Although, it has been hypothesized that faster growing individuals would do worse in dealing with suboptimal temperatures, this type of cost has never been explored empirically. Furthermore, the mechanistic basis of the physiological costs of rapid growth is largely unexplored. Methodology/Principal Finding: Larvae of the damselfly Ischnura elegans from two univoltine northern and two multivoltine southern populations were reared at three temperatures and after emergence given a cold shock. Cold resistance, measured by chill coma recovery times in the adult stage, was lower in the southern populations. The faster larval growth rates in the southern populations contributed to this latitudinal pattern in cold resistance. In accordance with their assumed role in cold resistance, Hsp70 levels were lower in the southern populations, and faster growing larvae had lower Hsp70 levels. Yet, individual variation in Hsp70 levels did not explain variation in cold resistance. Conclusions/Significance: We provide evidence for a novel cost of rapid growth: reduced cold resistance. Our results indicate that the reduced cold resistance in southern populations of animals that change voltinism along the latitudinal gradient may not entirely be explained by thermal selection per se but also by the costs of time constraint-induced higher growth rates. This also illustrates that stressors imposed in the larval stage may carry over and shape fitness in the adul