Biochemical markers of iron status and iron accumulation in peritoneal dialysis patients treated with ferric citrate.

BACKGROUND: Hyperphosphataemia is a common complication of kidney disease. Current dialysis techniques do not provide enough phosphorus clearance, hence the need to use phosphorus binders. Treatment options include calcium carbonate, calcium acetate, lanthanum carbonate, sevelamer hydrochloride and iron-based binders. Patients receiving peritoneal dialysis (PD) with sustained elevated ferritin levels exceeding 800 ng/mL are at a higher risk of death. We identify PD patients treated with iron-based binders and compare ferritin and risk of iron accumulation to patients treated with non-iron-based binders. METHODS: All records of patients receiving PD at Emory dialysis centres until 30 October 2021 were reviewed for phosphorus binders. Basic demographics and laboratory data were time-referenced to the days on treatment with a particular binder. Patients were followed until discontinuation of the phosphorus binder, death, transplant, transfer to another dialysis provider or censoring at 36 months after medication was started. RESULTS: Compared to calcium acetate and sevelamer, ferric citrate utilisation in PD patients resulted in a sustained increase in ferritin. The proportion of patients with a ferritin equal to or greater than 800 ng/dL and transferrin saturation greater than 40% increased over time in patients treated with ferric citrate and was higher during the second and third year of follow-up compared to baseline values and to patients treated with calcium acetate or sevelamer. Two patients (7%) treated with ferric citrate developed clinically significant haemosiderosis. CONCLUSIONS: Use of ferric citrated in PD resulted in significant iron accumulation as judged by ferritin levels.

Gut Microbiome-Derived Uremic Toxin Levels in Hemodialysis Patients on Different Phosphate Binder Therapies.

INTRODUCTION: Constipation is prevalent in patients with kidney failure partly due to the use of medication, such as phosphate binders. We hypothesized that serum levels of gut microbiome-derived uremic toxins (UTOX) may be affected by the choice of phosphate binder putatively through its impact on colonic transit time. We investigated two commonly prescribed phosphate binders, sevelamer carbonate (SEV) and sucroferric oxyhydroxide (SFO), and their association with gut microbiome-derived UTOX levels in hemodialysis (HD) patients. METHODS: Weekly blood samples were collected from 16 anuric HD participants during the 5-week observational period. All participants were on active phosphate binder monotherapy with either SFO or SEV for at least 4 weeks prior to enrollment. Eight UTOX (7 gut microbiome-derived) and tryptophan were quantified using liquid chromatography-mass spectrometry. Serum phosphorus, nutritional, and liver function markers were also measured. For each substance, weekly individual levels, the median concentration per participant, and differences between SFO and SEV groups were reported. Patient-reported bowel movements, by the Bristol Stool Scale (BSS), and pill usage were assessed weekly. RESULTS: The SEV group reported a 3.3-fold higher frequency of BSS stool types 1 and 2 (more likely constipated, p < 0.05), whereas the SFO group reported a 1.5-fold higher frequency of BSS stool types 5-7 (more likely loose stool and diarrhea, not significant). Participants in the SFO group showed a trend toward better adherence to phosphate binder therapy (SFO: 87.6% vs. SEV: 66.6%, not significant). UTOX, serum phosphorus, nutritional and liver function markers, and tryptophan were not different between the two groups. CONCLUSION: There was no difference in the gut microbiome-derived UTOX levels between phosphate binders (SFO vs. SEV), despite SFO therapy resulting in fewer constipated participants. This pilot study may inform study design of future clinical trials and highlights the importance of including factors beyond bowel habits and their association with UTOX levels.

A Randomized Trial of Tenapanor and Phosphate Binders as a Dual-Mechanism Treatment for Hyperphosphatemia in Patients on Maintenance Dialysis (AMPLIFY).

BACKGROUND: Hyperphosphatemia is associated with cardiovascular morbidity and mortality in patients receiving maintenance dialysis. It is unknown whether combining two therapies with different mechanisms of action-tenapanor, an inhibitor of paracellular phosphate absorption, and phosphate binders-is safe and effective for the management of hyperphosphatemia in patients receiving maintenance dialysis. METHODS: This double-blind phase 3 trial enrolled 236 patients undergoing maintenance dialysis with hyperphosphatemia (defined in this trial as serum phosphorus 5.5-10 mg/dl inclusive) despite receiving phosphate binder therapy (sevelamer, nonsevelamer, sevelamer plus nonsevelamer, or multiple nonsevelamer binders). These participants were randomly assigned to receive oral tenapanor 30 mg twice daily or placebo for 4 weeks. The primary efficacy end point was the change in serum phosphorus concentration from baseline to week 4. RESULTS: Of the 236 randomized patients, 235 (99.6%) were included in the full analysis set; this included 116 in the tenapanor plus binder group and 119 in the placebo plus binder group. A total of 228 patients (96.6%) completed the 4-week treatment period. In the full analysis set (mean age 54.5 years, 40.9% women), patients treated with tenapanor plus binder achieved a larger mean change in serum phosphorus concentration from baseline to week 4 compared with placebo plus binder (-0.84 versus -0.19 mg/dl, P<0.001). Diarrhea was the most commonly reported adverse event, resulting in study drug discontinuation in four of 119 (3.4%) and two of 116 (1.7%) patients receiving tenapanor plus binder or placebo plus binder, respectively. CONCLUSIONS: A dual-mechanism treatment using both tenapanor and phosphate binders improved control of hyperphosphatemia in patients undergoing maintenance dialysis compared with phosphate binders alone. CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER: AMPLIFY, NCT03824587.

Characteristics of Patients Who Achieve Serum Phosphorus Control on Sucroferric Oxyhydroxide or Sevelamer Carbonate: A post hoc Analysis of a Phase 3 Study.

INTRODUCTION: Control of hyperphosphatemia in patients on dialysis remains a major challenge. OBJECTIVE: This study evaluated predictors of serum phosphorus (sP) control among dialysis patients treated with noncalcium, oral phosphate binder therapy in a phase 3 clinical trial. METHODS: Post hoc analyses were performed using data for patients with hyperphosphatemia who received 52 weeks of treatment with sucroferric oxyhydroxide (SFOH) or sevelamer carbonate (sevelamer). Patients were categorized into those who achieved sP control (n = 302; defined as sP ≤ 5.5 mg/dL at week 52), and those with uncontrolled sP (n = 195; sP >5.5 mg/dL at week 52). Because SFOH and sevelamer have previously demonstrated similar effects on chronic kidney disease-mineral-bone disorder parameters in this study, the treatment groups were pooled. RESULTS: Average age at baseline was higher among sP-controlled versus sP-uncontrolled patients (56.9 vs. 53.4 years; p = 0.005). Baseline sP levels were significantly lower among sP-controlled versus sP-uncontrolled patients (7.30 vs. 7.85 mg/dL; p < 0.001), and sP reductions from baseline were significantly greater in the sP-controlled group (-2.89 vs. -0.99 mg/dL at week 52; p < 0.001). Logistic regression analysis identified higher baseline sP levels (odds ratio [OR] = 0.86, 95% confidence interval [CI]: 0.765-0.960), no concomitant active vitamin D therapy use (OR = 0.51, 95% CI: 0.328-0.804), and higher body mass index at baseline (OR = 0.96, 95% CI: 0.937-0.992) as significant predictors of uncontrolled sP. CONCLUSION: This analysis indicates that sP control may be more challenging in younger patients with high sP levels. Closer monitoring and management of serum phosphorus levels may be required in this population.

Randomized Crossover Trial of Phosphate-binding Medication on Serum Phosphate Levels in Patients With Aortic Stenosis.

PURPOSE: Aortic stenosis is a common cause of valvular heart disease with no means of prevention. The recognized association between aortic stenosis and serum phosphate raises the possibility of preventing progression of the disorder by using phosphate-binding drugs, but there is uncertainty whether such treatment lowers serum phosphate levels in patients without diagnosed renal failure. This pilot study was conducted to answer this question in patients with aortic stenosis. METHODS: A randomized, double-blind, crossover trial of the phosphate-binding drug sevelamer was conducted in 72 patients. Patients were prescribed sevelamer 0.8 g (low-dose), sevelamer 2.4 g (high-dose), and matching placebo, 3 times daily with food; each regimen lasted 6 weeks and was allocated at random. Serum phosphate levels were measured at the end of each treatment period, and within-person levels were compared. FINDINGS: Sixty-one patients completed the 3 treatment periods. There was no significant difference in the mean end-treatment phosphate levels across all patients (3.38, 3.36, and 3.31 mg/dL with placebo, low-dose sevelamer, and high-dose sevelamer, respectively). Post hoc analysis showed a reduction in phosphate levels with increasing sevelamer dose in the highest baseline phosphate quartile group; a 0.3 mg/dL reduction (mean, 4.09 mg/dL with placebo, 3.95 mg/dL with low-dose sevelamer, and 3.79 mg/dL with high-dose sevelamer; Ptrend = 0.027). IMPLICATIONS: Sevelamer had no overall statistically significant effect in lowering serum phosphate levels, but a reduction was observed in patients with phosphate levels in the highest quartile group of the population distribution. This hypothesis-generating result requires confirmation in an independent study. If confirmed, a trial of sevelamer in preventing the progression of aortic stenosis may be justified in patients with high phosphate levels. ISRCTN Registry identifier: ISRCTN17365679.

Effectiveness of sucroferric oxyhydroxide in patients on on-line hemodiafiltration in real-world clinical practice: A retrospective study / Eficácia do oxihidróxido sucroférrico em pacientes em hemodiafiltração on-line na realidade da prática clínica: um estudo retrospectivo

Abstract Introduction: Hyperphosphatemia is a serious consequence of chronic kidney disease and has been associated with an increased risk for cardiovascular disease. Controlling serum phosphorus levels in patients on dialysis is a challenge for the clinicians and implies, in most cases, the use of phosphate binders (PB). Part of the reason for this challenge is poor adherence to treatment because of the high pill burden in this patient group. Objective: To assess the real-world effectiveness of sucroferric oxyhydroxide (SO) in controlling serum phosphorus levels and determine the associated pill burden. Methods: A multicenter, quantitative, retrospective, before-after study was conducted with patients receiving online hemodiafiltration. Patients who switched to SO as a part of routine care were included in the study. PB treatment, number of pills, serum phosphorus levels, and intravenous iron medication and dosage were collected monthly during the six months of treatment with either PB or SO. Results: A total of 42 patients were included in the study. After switching from a PB to SO, the prescribed pills/day was reduced 67% from 6 pills/day to 2 pills/day (p < 0.001) and the frequency of pill intake was lowered from 3 times/day to 2 times/day (p < 0.001). During the treatment with SO, the proportion of patients with serum phosphorus ≤ 5.5 mg/dL increased from 33.3% at baseline to 45% after six months of treatment. Conclusion: During the six-month follow-up with SO, serum phosphorus levels were controlled with one third of the pills/day compared to other PB.

Resumo Introdução: A hiperfosfatemia é uma grave consequência da doença renal crônica associada a risco aumentado de doença cardiovascular. O controle dos níveis séricos de fósforo dos pacientes em diálise é um desafio que requer, na maioria dos casos, o uso de quelantes de fosfato (QF). Parte da dificuldade se deve à baixa adesão ao tratamento oriunda do grande número de medicamentos receitados para esse grupo de pacientes. Objetivo: Avaliar a real eficácia do oxihidróxido sucroférrico (OHS) no controle dos níveis séricos de fósforo e determinar a carga de comprimidos associada. Métodos: Estudo multicêntrico, quantitativo, retrospectivo, antes e depois conduzido com pacientes em hemodiafiltração on-line. Pacientes remanejados para OHS como parte dos cuidados de rotina foram incluídos no estudo. Tratamento com QF, número de comprimidos, níveis séricos de fósforo, reposição férrica endovenosa e dosagens foram registrados mensalmente durante seis meses de tratamento com QF ou OHS. Resultados: Foram incluídos 42 pacientes no estudo. Após a mudança de QF para OHS, o número de comprimidos prescritos por dia caiu em 67%, de seis para duas unidades diárias (p < 0,001). A frequência de ingestão de comprimidos caiu de três para duas vezes ao dia (p < 0,001). Durante o tratamento com OHS, o percentual de pacientes com fósforo sérico ≤ 5,5 mg/dL aumentou de 33,3% no início para 45% após seis meses de tratamento. Conclusão: Durante os seis meses de seguimento com OHS, os níveis séricos de fósforo foram controlados com um terço dos comprimidos por dia em relação aos tratamentos com outros QF.

Effectiveness of sucroferric oxyhydroxide in patients on on-line hemodiafiltration in real-world clinical practice: A retrospective study.

INTRODUCTION: Hyperphosphatemia is a serious consequence of chronic kidney disease and has been associated with an increased risk for cardiovascular disease. Controlling serum phosphorus levels in patients on dialysis is a challenge for the clinicians and implies, in most cases, the use of phosphate binders (PB). Part of the reason for this challenge is poor adherence to treatment because of the high pill burden in this patient group. OBJECTIVE: To assess the real-world effectiveness of sucroferric oxyhydroxide (SO) in controlling serum phosphorus levels and determine the associated pill burden. METHODS: A multicenter, quantitative, retrospective, before-after study was conducted with patients receiving online hemodiafiltration. Patients who switched to SO as a part of routine care were included in the study. PB treatment, number of pills, serum phosphorus levels, and intravenous iron medication and dosage were collected monthly during the six months of treatment with either PB or SO. RESULTS: A total of 42 patients were included in the study. After switching from a PB to SO, the prescribed pills/day was reduced 67% from 6 pills/day to 2 pills/day (p < 0.001) and the frequency of pill intake was lowered from 3 times/day to 2 times/day (p < 0.001). During the treatment with SO, the proportion of patients with serum phosphorus ≤ 5.5 mg/dL increased from 33.3% at baseline to 45% after six months of treatment. CONCLUSION: During the six-month follow-up with SO, serum phosphorus levels were controlled with one third of the pills/day compared to other PB.

Effects of sucroferric oxyhydroxide and sevelamer carbonate on chronic kidney disease-mineral bone disorder parameters in dialysis patients.

BACKGROUND: Treatment of hyperphosphataemia is the primary goal of chronic kidney disease-mineral and bone disorder (CKD-MBD) management. This post hoc analysis of a randomized, Phase 3 study evaluated the effects of 1-year treatment with the phosphate binders sucroferric oxyhydroxide or sevelamer carbonate ('sevelamer') on CKD-MBD indices among dialysis patients with hyperphosphataemia. METHODS: After a 2- to 4-week washout from previous phosphate binders, 1059 patients were randomized 2:1 to sucroferric oxyhydroxide 1.0-3.0 g/day (n = 710) or sevelamer 2.4-14.4 g/day (n = 349) for up to 24 weeks. Eligible patients enrolled in a 28-week extension. This post hoc analysis was performed for patients who completed ≥1 year of continuous treatment (n = 549). As the treatment groups showed similar CKD-MBD outcomes, the data were pooled for this analysis. RESULTS: Phosphate-binder therapy was associated with significant and sustained 30% reductions in serum phosphorus (P < 0.001). Median intact fibroblast growth factor-23 (FGF-23) also significantly decreased (P < 0.001) by 64% over 1 year. Intact parathyroid hormone decreased significantly after 24 weeks (P < 0.001), but levels returned to near baseline values by Week 52; minimal changes in serum calcium were observed. Of the bone resorption markers evaluated, tartrate-resistant acid phosphatase 5b (TRAP5b) decreased significantly (P < 0.001), whereas CTx increased transiently but returned to baseline levels by Week 52. The bone formation markers bone-specific alkaline phosphatase and osteocalcin both increased over 1 year of treatment. CONCLUSIONS: Overall, 1 year of sucroferric oxyhydroxide or sevelamer treatment significantly reduced serum FGF-23, which has been associated with clinical benefit in patients with CKD. The trend towards increased bone formation marker levels indicates a beneficial effect on bone metabolism.

Phosphate binders for preventing and treating chronic kidney disease-mineral and bone disorder (CKD-MBD).

BACKGROUND: Phosphate binders are used to reduce positive phosphate balance and to lower serum phosphate levels for people with chronic kidney disease (CKD) with the aim to prevent progression of chronic kidney disease-mineral and bone disorder (CKD-MBD). This is an update of a review first published in 2011. OBJECTIVES: The aim of this review was to assess the benefits and harms of phosphate binders for people with CKD with particular reference to relevant biochemical end-points, musculoskeletal and cardiovascular morbidity, hospitalisation, and death. SEARCH METHODS: We searched the Cochrane Kidney and Transplant Register of Studies up to 12 July 2018 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov. SELECTION CRITERIA: We included randomised controlled trials (RCTs) or quasi-RCTs of adults with CKD of any GFR category comparing a phosphate binder to another phosphate binder, placebo or usual care to lower serum phosphate. Outcomes included all-cause and cardiovascular death, myocardial infarction, stroke, adverse events, vascular calcification and bone fracture, and surrogates for such outcomes including serum phosphate, parathyroid hormone (PTH), and FGF23. DATA COLLECTION AND ANALYSIS: Two authors independently selected studies for inclusion and extracted study data. We applied the Cochrane 'Risk of Bias' tool and used the GRADE process to assess evidence certainty. We estimated treatment effects using random-effects meta-analysis. Results were expressed as risk ratios (RR) for dichotomous outcomes together with 95% confidence intervals (CI) or mean differences (MD) or standardised MD (SMD) for continuous outcomes. MAIN RESULTS: We included 104 studies involving 13,744 adults. Sixty-nine new studies were added to this 2018 update.Most placebo or usual care controlled studies were among participants with CKD G2 to G5 not requiring dialysis (15/25 studies involving 1467 participants) while most head to head studies involved participants with CKD G5D treated with dialysis (74/81 studies involving 10,364 participants). Overall, seven studies compared sevelamer with placebo or usual care (667 participants), seven compared lanthanum to placebo or usual care (515 participants), three compared iron to placebo or usual care (422 participants), and four compared calcium to placebo or usual care (278 participants). Thirty studies compared sevelamer to calcium (5424 participants), and fourteen studies compared lanthanum to calcium (1690 participants). No study compared iron-based binders to calcium. The remaining studies evaluated comparisons between sevelamer (hydrochloride or carbonate), sevelamer plus calcium, lanthanum, iron (ferric citrate, sucroferric oxyhydroxide, stabilised polynuclear iron(III)-oxyhydroxide), calcium (acetate, ketoglutarate, carbonate), bixalomer, colestilan, magnesium (carbonate), magnesium plus calcium, aluminium hydroxide, sucralfate, the inhibitor of phosphate absorption nicotinamide, placebo, or usual care without binder. In 82 studies, treatment was evaluated among adults with CKD G5D treated with haemodialysis or peritoneal dialysis, while in 22 studies, treatment was evaluated among participants with CKD G2 to G5. The duration of study follow-up ranged from 8 weeks to 36 months (median 3.7 months). The sample size ranged from 8 to 2103 participants (median 69). The mean age ranged between 42.6 and 68.9 years.Random sequence generation and allocation concealment were low risk in 25 and 15 studies, respectively. Twenty-seven studies reported low risk methods for blinding of participants, investigators, and outcome assessors. Thirty-one studies were at low risk of attrition bias and 69 studies were at low risk of selective reporting bias.In CKD G2 to G5, compared with placebo or usual care, sevelamer, lanthanum, iron and calcium-based phosphate binders had uncertain or inestimable effects on death (all causes), cardiovascular death, myocardial infarction, stroke, fracture, or coronary artery calcification. Sevelamer may lead to constipation (RR 6.92, CI 2.24 to 21.4; low certainty) and lanthanum (RR 2.98, CI 1.21 to 7.30, moderate certainty) and iron-based binders (RR 2.66, CI 1.15 to 6.12, moderate certainty) probably increased constipation compared with placebo or usual care. Lanthanum may result in vomiting (RR 3.72, CI 1.36 to 10.18, low certainty). Iron-based binders probably result in diarrhoea (RR 2.81, CI 1.18 to 6.68, high certainty), while the risks of other adverse events for all binders were uncertain.In CKD G5D sevelamer may lead to lower death (all causes) (RR 0.53, CI 0.30 to 0.91, low certainty) and induce less hypercalcaemia (RR 0.30, CI 0.20 to 0.43, low certainty) when compared with calcium-based binders, and has uncertain or inestimable effects on cardiovascular death, myocardial infarction, stroke, fracture, or coronary artery calcification. The finding of lower death with sevelamer compared with calcium was present when the analysis was restricted to studies at low risk of bias (RR 0.50, CI 0.32 to 0.77). In absolute terms, sevelamer may lower risk of death (all causes) from 210 per 1000 to 105 per 1000 over a follow-up of up to 36 months, compared to calcium-based binders. Compared with calcium-based binders, lanthanum had uncertain effects with respect to all-cause or cardiovascular death, myocardial infarction, stroke, fracture, or coronary artery calcification and probably had reduced risks of treatment-related hypercalcaemia (RR 0.16, CI 0.06 to 0.43, low certainty). There were no head-to-head studies of iron-based binders compared with calcium. The paucity of placebo-controlled studies in CKD G5D has led to uncertainty about the effects of phosphate binders on patient-important outcomes compared with placebo.It is uncertain whether the effects of binders on clinically-relevant outcomes were different for patients who were and were not treated with dialysis in subgroup analyses. AUTHORS' CONCLUSIONS: In studies of adults with CKD G5D treated with dialysis, sevelamer may lower death (all causes) compared to calcium-based binders and incur less treatment-related hypercalcaemia, while we found no clinically important benefits of any phosphate binder on cardiovascular death, myocardial infarction, stroke, fracture or coronary artery calcification. The effects of binders on patient-important outcomes compared to placebo are uncertain. In patients with CKD G2 to G5, the effects of sevelamer, lanthanum, and iron-based phosphate binders on cardiovascular, vascular calcification, and bone outcomes compared to placebo or usual care, are also uncertain and they may incur constipation, while iron-based binders may lead to diarrhoea.

A systematic review on the efficacy and safety of PA21 versus sevelamer in dialysis patients.

AIM: To evaluate the efficacy and safety of PA21 versus sevelamer in dialysis patients. METHODS: We searched Medline, Embase, Science Citation Index, Cochrane Central Register of Controlled Trials, and Clinical Trial Registries for randomized controlled trials comparing PA21 and sevelamer in dialysis patients. RESULTS: Four studies were included. Compared with sevelamer group, PA21 needed fewer mean daily number of tablets (WMD, - 7.97 pill; 95% CI, - 11.28 to - 4.65, p < 0.00001), developed fewer all adverse events (RR = 1.05; 95% CI, 1.00 to 1.11, p = 0.05), and developed fewer gastrointestinal adverse events (RR = 1.32; 95% CI, 1.15 to 1.53, p = 0.0001). There was no significant difference in serum phosphorus between two groups (WMD, - 0.07 mmol/L; 95% CI, - 0.15 to 0.02, p = 0.12). As for serum calcium, there was also no significant difference between two groups (WMD, 0.27 mmol/L; 95% CI, - 0.63 to 1.17, p = 0.55). CONCLUSION: PA21 can effectively control serum phosphorus with lower pill burden and less side effects than sevelamer. PA21 might be another valuable choice for dialysis patients with hyperphosphatemia when patients are unable to tolerate sevelamer.

A Real-world Cost-effectiveness Analysis of Sevelamer Versus Calcium Acetate in Korean Dialysis Patients.

PURPOSE: Sevelamer, a noncalcium phosphate binder, has been shown to attenuate the progression of vascular calcification and improve survival in patients with chronic kidney disease undergoing dialysis compared with calcium-based binders. Using real-world data from a cohort study and the Health Insurance Review and Assessment Service database, we conducted a cost-effectiveness analysis comparing sevelamer with calcium acetate in dialysis patients from the perspective of the National Health Insurance Service in South Korea. METHODS: Data (demographic, diagnostic, laboratory, and survival) from 4674 patients undergoing dialysis enrolled in a multicenter prospective cohort study conducted in South Korea between September 2008 and December 2012 were linked to phosphate binder use, hospitalization, and cost data available from the Health Insurance Review and Assessment Service database. After propensity score matching, a dataset comprising comparable patients treated with either sevelamer (n = 501) or calcium acetate (n = 501) was used in the cost-effectiveness analysis. A Markov model was used to estimate costs, life years, quality-adjusted life years (QALYs), and cost-effectiveness over each patient's lifetime. Forty-month treatment-specific overall survival (OS) data available from the dataset were extrapolated to lifetime survival with the use of regression analysis. FINDINGS: Patients had a mean age of 56.3 years and were treated with dialysis for a mean duration of 67.6 months. Compared with calcium acetate, sevelamer was associated with an incremental cost of South Korean Won (₩) 12,246,911 ($10,819) and a gain of 1.758 life years and 1.108 QALYs per patient. This outcome yielded incremental cost-effectiveness ratios of ₩6,966,350 ($6154) and ₩11,057,699 ($9768) per life year and QALY gained, respectively. Conclusions regarding sevelamer's cost-effectiveness were insensitive to alternative assumptions in time horizon, discount rate, hospitalization rate, costs, and health utility estimates, and they remained consistent in 100% of the model iterations, considering a willingness-to-pay threshold of ₩31,894,720 ($28,176) per QALY gained. IMPLICATIONS: This analysis of real-world data found that sevelamer's higher cost relative to calcium acetate was adequately offset by improved survival among patients undergoing dialysis in South Korea. As such, sevelamer offers good value for money, representing a cost-effective alternative to calcium-based binders.

Phosphate-Binder Use in US Dialysis Patients: Prevalence, Costs, Evidence, and Policies.

Medicare costs for phosphate binders for US dialysis patients and patients with chronic kidney disease enrolled in Medicare Part D exceeded $1.5 billion in 2015. Previous data have shown that Part D costs for mineral and bone disorder medications increased faster than costs for all Part D medications for dialysis patients. Despite extensive use of phosphate binders and escalating costs, conclusive evidence is lacking that they improve important clinical end points in dialysis patients or non-dialysis-dependent patients with chronic kidney disease. Using dialysis patient data from the US Renal Data System and laboratory information from the Centers for Medicare & Medicaid Services (CMS) CROWNWeb data, we update information on trends in phosphate-binder use, calcium and phosphorus values, and costs for Medicare-covered dialysis patients. We discuss these results in the context of evidence from clinical trials, meta-analyses, and observational studies evaluating phosphate-binder efficacy, safety, comparative effectiveness, and cost-effectiveness. Based on our analysis, we note a need for US Food and Drug Administration guidance regarding clinical evaluation of new phosphate binders, and we suggest that it would be in CMS' best interest to fund a clinical trial to assess whether lower versus higher phosphate concentrations improve hard clinical outcomes, and if so, whether particular phosphate binders are superior to placebo or other binders in improving these outcomes.

Cómo estimar la eficacia de un captor del fósforo / How to assess the efficacy of phosphate binders

Antecedentes y objetivos: Es difícil estimar clínicamente la eficacia de los captores de fósforo (CP). Este estudio analiza los cambios que se producen en la fosfatemia y excreción urinaria de fósforo tras la administración de CP a pacientes con enfermedad renal crónica, y la utilidad de la relación entre la excreción urinaria de fósforo y la tasa de catabolismo proteico (Po/TCP) en la estimación de la eficacia de estos fármacos. Métodos: Estudio retrospectivo de observación en una cohorte de pacientes adultos con enfermedad renal crónica en estadios 4-5. Se compararon parámetros bioquímicos basales y 45-60 días después de un tratamiento con dieta baja en fósforo más CP (subgrupo «captor»=260 pacientes) o solo con los consejos dietéticos (subgrupo «control»=79 pacientes). Resultados: La carga de fósforo (excreción urinaria total) por unidad de función renal (Po/GFR) fue el parámetro mejor relacionado con la fosfatemia (R2=0,61). La cifra media de Po/TCP fue de 8,2±2,3mg de fósforo por gramo de proteína. Tras la administración de CP, la fosfatemia descendió un 11%, la fosfaturia un 22%, la tasa de catabolismo proteico un 7% y la Po/TCP un 15%. En el subgrupo control la Po/TCP se incrementó un 20%. La excreción urinaria de fósforo y de nitrógeno ureico se correlacionaron fuertemente de forma lineal antes y después del tratamiento con CP o tras los consejos dietéticos en el subgrupo control. Conclusiones: La Po/TCP es un parámetro que podría reflejar la absorción intestinal de fósforo y, por tanto, sus variaciones tras la administración de CP podrían servir para estimar la eficacia de estos fármacos (AU)

Background and aims: The efficacy of phosphate binders is difficult to be estimated clinically. This study analyzes the changes in serum phosphate and urinary phosphate excretion after the prescription of phosphate binders (PB) in patients with chronic kidney disease stage 4-5 pre-dialysis, and the usefulness of the ratio between total urinary phosphate and protein catabolic rate (Pu/PCR) for estimating the efficacy of PB. Methods: This retrospective observational cohort study included adult chronic kidney disease patients. Biochemical parameters were determined baseline and after 45-60 days on a low phosphate diet plus PB (‘binder’ subgroup=260 patients) or only with dietary advice (‘control’ subgroup=79 patients). Results: Phosphate load (total urinary excretion) per unit of renal function (Pu/GFR) was the best parameter correlated with serum phosphate levels (R2=0.61). Mean±SD level of Pu/PCR was 8.2±2.3mg of urinary phosphate per each g of estimated protein intake. After treatment with PB, serum phosphate levels decreased by 11%, urinary phosphate 22%, protein catabolic rate 7%, and Pu/PCR 15%. In the control subgroup, Pu/PCR increased by 20%. Urinary phosphate and urea nitrogen excretion correlated strongly, both baseline and after PB or dietary advice. Conclusions: The proposed parameter Pu/PCR may reflect the rate of intestinal phosphate absorption, and therefore, its variations after PB prescription may be a useful tool for estimating the pharmacological efficacy of these drugs (AU)

Efficacy and safety of sucroferric oxyhydroxide compared with sevelamer hydrochloride in Japanese haemodialysis patients with hyperphosphataemia: A randomized, open-label, multicentre, 12-week phase III study.

AIM: We aimed to investigate the non-inferiority of PA21 (sucroferric oxyhydroxide) to sevelamer hydrochloride (sevelamer) in terms of efficacy and safety in Japanese haemodialysis patients with hyperphosphataemia. METHODS: In this Phase III, open-label, multicentre study, 213 haemodialysis patients with hyperphosphataemia were randomized to PA21 or sevelamer treatment for 12 weeks. The primary outcome was adjusted serum phosphorus concentration at the end of treatment; the non-inferiority of PA21 was confirmed if the upper limit of the two-sided 95% confidence interval (CI) is ≤0.32 mmol/L. Secondary outcomes were corrected serum calcium and intact-parathyroid hormone concentrations. Adverse events (AEs) and adverse drug reactions (ADRs) were evaluated. RESULTS: The adjusted mean serum phosphorus concentration at the end of treatment confirmed the non-inferiority of PA21 for lowering serum phosphorus compared with sevelamer (1.62 vs 1.72 mmol/L; difference, -0.11 mmol/L; 95% CI, -0.20 to -0.02 mmol/L). The mean daily tablet intake was 5.6 ± 2.6 and 18.7 ± 7.1 tablets in the PA21 and sevelamer groups, respectively. The incidences of AEs and ADRs were not significantly different between the two groups. CONCLUSION: The non-inferiority of PA21 to sevelamer was confirmed for the treatment of Japanese haemodialysis patients with hyperphosphataemia. PA21 was effective, safe, and well tolerated, while having a considerably lower pill burden than sevelamer.

Factors associated with serum fetuin-A concentrations after long-term use of different phosphate binders in hemodialysis patients.

BACKGROUND: Fetuin-A is known as a circulating inhibitor of vascular calcification. Factors associated with serum fetuin-A concentrations after long-term use of different phosphate binders in hemodialysis patients is still uncertain. METHODS: In the post-hoc study, we analyzed serum fetuin-A and biochemical factors (Ca, P, i-PTH, hsCRP, TG, LDL-C) in 50 hemodialysis patients, who completed a 48-week, open-Label, controlled randomized parallel-group study. 23 patients received sevelamer and 27 patients received calcium carbonate. RESULTS: After the 48-week treatment, the sevelamer group had less serum calcium increment, less iPTH decrement, more ALK-P increment, more hsCRP decrement and more LDL-C decrement. There was no significant difference in the serum fetuin-A decrement between two groups. Decreased serum fetuin-A levels were found after 48-week treatment in both groups: from 210.61 (104.73) to 153.85 (38.64) ug/dl, P = 0.003 in sevelamer group, from 203.95 (107.87) to 170.90 (58.02) ug/mL, P =0.002 in calcium group. The decrement in serum fetuin-A (Δfetuin-A) levels was associated with ΔCa (ρ = - 0.230, P = 0.040), ΔiPTH (ρ = 0.306, P = 0.031) and Δalbumin (ρ = 0.408, P = 0.003), not associated with sevelamer use, ΔP and ΔhsCRP. CONCLUSION: After long-term sevelamer or calcium carbonate treatment, both groups of maintenance HD patients had lower serum fetuin-A levels. Serum levels of increased calcium, decreased iPTH and decreased albumin were associated with the serum fetuin-A decrement.

Administration of Ferric Citrate Hydrate Decreases Circulating FGF23 Levels Independently of Serum Phosphate Levels in Hemodialysis Patients with Iron Deficiency.

BACKGROUND/AIM: Dietary phosphate intake and vitamin D receptor activator (VDRA) regulate fibroblast growth factor 23 (FGF23); iron may modulate FGF23 metabolism. We aimed to determine whether oral iron supplementation influences serum FGF23 concentration in hemodialysis (HD) patients, while excluding the effect of dietary phosphate intake. METHODS: This prospective study enrolled 27 maintenance HD patients with iron deficiency and hyperphosphatemia treated with sevelamer-HCl. The phosphate binder was changed from sevelamer-HCl to ferric citrate hydrate (FCH) to maintain constant phosphate levels. VDRA, other phosphate binders, and cinacalcet HCl were not changed. Serum intact FGF23, C-terminal FGF23 (C-term FGF23), intact parathyroid hormone (PTH), 1,25(OH)2D and other parameters were monitored for 12 weeks. RESULTS: Serum phosphate levels (5.89 ± 1.45 mg/dl at baseline, 5.54 ± 1.35 mg/dl at 12 weeks) and 1,25(OH)2D levels were unchanged. Serum ferritin levels increased from 25.6 ± 24.3 ng/ml at baseline to 55.8 ± 33.5 ng/ml at 12 weeks with FCH administration. Serum intact FGF23 and C-term FGF23 levels significantly decreased at 12 weeks compared with baseline (2,000 (1,300.0-3,471.4) to 1,771.4 (1,142.9-2,342.9) pg/ml, p = 0.01, and 1,608.7 (634.8-2,308.7) to 1,165.2 (626.1-1,547.8) RU/ml, p = 0.007, respectively); serum intact PTH levels significantly increased (96 (65-125) to 173 (114-283) pg/ml, p < 0.001). CONCLUSIONS: Oral FCH administration decreased serum intact FGF23 and C-term FGF23 levels and increased intact PTH levels; phosphate and 1,25(OH)2D levels were unchanged. Oral FCH administration to treat iron deficiency is a possible strategy for reducing serum FGF23 levels independent of phosphate and VDRA.

Interventions for metabolic bone disease in children with chronic kidney disease.

BACKGROUND: Bone disease is common in children with chronic kidney disease (CKD) and when untreated may result in bone deformities, bone pain, fractures and reduced growth rates. This is an update of a review first published in 2010. OBJECTIVES: This review aimed to examine the benefits (improved growth rates, reduced risk of bone fractures and deformities, reduction in PTH levels) and harms (hypercalcaemia, blood vessel calcification, deterioration in kidney function) of interventions (including vitamin D preparations and phosphate binders) for the prevention and treatment of metabolic bone disease in children with CKD. SEARCH METHODS: We searched the Cochrane Kidney and Transplant Specialised Register to 8 September 2015 through contact with the Trial's Search Co-ordinator using search terms relevant for this review. SELECTION CRITERIA: We included randomised controlled trials (RCTs) comparing different interventions used to prevent or treat bone disease in children with CKD stages 2 to 5D. DATA COLLECTION AND ANALYSIS: Data were assessed for study eligibility, risk of bias and extracted independently by two authors. Results were reported as risk ratios (RR) or risk differences (RD) with 95% confidence intervals (CI) for dichotomous outcomes. For continuous outcomes the mean difference (MD) or standardised mean difference (SMD) with 95% confidence intervals (CI) was used. Statistical analyses were performed using the random-effects model. MAIN RESULTS: This review included 18 studies (576 children); three new studies were added for this update. Adequate sequence generation and allocation concealment were reported in 12 and 11 studies respectively. Only four studies reported blinding of children, investigators or outcome assessors. Nine studies were at low risk of attrition bias and 12 studies were at low risk of selective reporting bias.Eight different interventions were compared. Two studies compared intraperitoneal (IP) with oral calcitriol. PTH levels were significantly lower with IP compared with oral calcitriol (1 study: MD -501.00 pg/mL, 95% CI -721.54 to -280.46) but the number of children with abnormal bone histology did not differ between treatments. Three studies compared intermittent with daily oral calcitriol. The change in mean height SDS (1 study: MD 0.13, 95% CI -0.22 to 0.48) and the percentage fall in parathyroid hormone (PTH) levels at eight weeks (1 study: MD -5.50%, 95% CI -32.37 to 21.37) and 12 months (1 study: MD -6.00% 95% CI -25.27 to 13.27) did not differ between treatments.Four studies compared active vitamin D preparations (calcitriol, paricalcitol, 1α-hydroxyvitamin D) with placebo or no specific treatment. One study reported vitamin D preparations significantly reduced PTH levels (-55.00 pmol/L, 95% CI -83.03 to -26.97). There was no significant difference in hypercalcaemia risk with vitamin D preparations compared with placebo or no specific treatment (4 studies, 103 children: RD 0.08 mg/dL, 95% CI -0.08 to 0.24). However, there was heterogeneity (I(2) = 55%) with one study showing a significantly greater risk of hypercalcaemia with intravenous (IV) calcitriol administration. Two studies (97 children) compared calcitriol with other vitamin D preparations and both found no significant differences in growth between preparations.Two studies compared ergocalciferol in patients with CKD and vitamin D deficiency. Elevated PTH levels developed significantly later in ergocalciferol treated children (1 study: hazard ratio 0.30, 95% CI 0.09 to 0.93) though the number with elevated PTH levels did not differ between groups (1 study, 40 children: RR 0.33, 95% CI 0.11 to 1.05).Two studies compared calcium carbonate with aluminium hydroxide as phosphate binders. One study (17 children: MD -0.86 SDS, 95% CI -2.24 to 0.52) reported no significant difference in mean final height SDS between treatments. Three studies compared sevelamer with calcium-containing phosphate binders. There were no significant differences in the final calcium, phosphorus or PTH levels between binders. More episodes of hypercalcaemia occurred with calcium-containing binders. One study reported no significant differences between calcitriol and doxercalciferol in bone histology or biochemical parameters. AUTHORS' CONCLUSIONS: Bone disease, assessed by changes in PTH levels, is improved by all vitamin D preparations. However, no consistent differences between routes of administration, frequencies of dosing or vitamin D preparations were demonstrated. Although fewer episodes of high calcium levels occurred with the non-calcium-containing phosphate binder, sevelamer, compared with calcium-containing binders, there were no differences in serum phosphorus and calcium overall and phosphorus values were reduced to similar extents. All studies were small with few data available on patient-centred outcomes (growth, bone deformities) and limited data on biochemical parameters or bone histology resulting in considerable imprecision of results thus limiting the applicability to the care of children with CKD.

Use of sevelamer in chronic kidney disease: beyond phosphorus control.

Sevelamer is a non-calcium phosphate binder used in advanced chronic kidney disease (CKD) and in dialysis for hyperphosphataemia control. Several experimental, observational studies and clinical trials have shown that sevelamer has pleiotropic effects, beyond hyperphosphataemia control, including actions on inflammation, oxidative stress, lipid profile and atherogenesis, vascular calcification, endothelial dysfunction and the reduction of several uremic toxins. This is the biological basis for its global effect on cardiovascular morbidity and mortality in patients with chronic kidney disease. This review focuses on these pleiotropic actions of sevelamer and their impact on cardiovascular health, with the experience published after more than ten years of clinical expertise.

Effects of phosphorus-restricted diet and phosphate-binding therapy on outcomes in patients with chronic kidney disease.

BACKGROUND: Phosphorus is associated with mortality in patients with chronic kidney disease (CKD) not on dialysis, possibly through phosphorus-dependent vascular calcification. Although a phosphorus-restricted diet reduces serum phosphorus, it is unlikely that it reduces vascular calcification progression in CKD. This study evaluated whether a combined strategy of phosphorus-restricted diet and phosphate-binding therapy can reduce the risk of all-cause mortality and/or dialysis initiation by attenuating coronary artery calcification (CAC) progression in non-dialysis CKD patients. METHODS: This was a post hoc analysis of a subgroup of patients from a study that evaluated the impact of two phosphorus binder regimens on hard outcomes in CKD. Patients (n = 113) with stage 3-4 CKD and evidence of CAC on a phosphorus-restricted diet were randomized to receive either calcium carbonate or sevelamer added to their phosphorus-restricted diet. End-points were death for any cause and initiation of dialysis. Patients were monitored to the first event or to conclusion of the 36-month follow-up. RESULTS: Overall, treatment with calcium carbonate was associated with increased CAC progression and occurrence of all-cause mortality, dialysis initiation, and the composite end-point. After adjustment for confounders, sevelamer use was the only independent predictive factor of reduced risk of each endpoint but only if CAC progression was either absent or moderate. Accelerated progression (annual CAC increase >75th percentile of the study cohort) increased the risk of all-cause mortality and composite end-point (p = 0.01) independently of the use of sevelamer. CONCLUSIONS: A significant reduction in all-cause mortality, dialysis initiation, and composite end-point risk was achieved by combining phosphorus-restricted diet and sevelamer in non-dialysis CKD patients with absent or moderate but not accelerated CAC progression. Future studies should investigate the role of serum phosphorus, the usefulness of a phosphorus-restricted diet, and the appropriateness of current normal ranges of serum phosphorus concentration in relation to events in non-dialyzed CKD patients.

[Pleiotropic effects of sevelamer: a model of intestinal tract chelating agent]. / Effets pléïotropes du sévélamer, précurseur d'agent chélateur de la voie intestinale.

The number of patients with chronic kidney disease (CKD) with its associated complications has increased dramatically worldwide in recent years. Therefore, many experimental and clinical studies have examined over the last decade the mechanisms involved, in order to explain the sharp increase in cardiovascular mortality. Hyperphosphatemia is a major problem in these patients especially at advanced stages of CKD, and it is associated with cardiovascular and mineral complications in these patients. Sevelamer is a phosphate binder that allows a better control of hyperphosphatemia, like other phosphate binder agents, but it has additional pleiotropic effects such as correcting certain abnormalities of lipid metabolism and clearance of several uremic toxins. These effects of sevelamer, restricted to the intestinal lumen, underline the importance of intestinal pathway in CKD and open the way to new therapeutic strategies for the management of the CKD and its complications.