Oral phosphate binders and incident osteoporotic fracture in patients on dialysis.

BACKGROUND AND HYPOTHESIS: End-stage kidney disease (ESKD) has an elevated risk of osteoporotic fractures in relation to mineral and bone disorder (MBD) as well as conventional risks of osteoporosis. We investigated the association between oral phosphate binders, the mainstay of MBD treatment, and osteoporotic fracture in dialysis patients. METHODS: We obtained data from the National Health Insurance database for incident dialysis patients without a history of osteoporotic fractures. Participants were categorized into four groups based on their initial 1-year prescription profiles: calcium-based phosphate binder (CBPB), non-calcium-based phosphate binder (NCBPB), both calcium and non-calcium-based binders (Mixed), and non-phosphate binder (non-user) groups. The primary outcome was the occurrence of new-onset osteoporotic fractures after 1 year of dialysis. Secondary outcomes included cardiovascular events and mortality. RESULTS: Out of 69 368 incident dialysis patients, 22 326, 5020, 2853, and 39 169 were included in the CBPB, NCBPB, mixed, and non-user groups, respectively. The overall risk of osteoporotic fractures was lower in patients taking any phosphate binders compared to non-users. Specifically, only the CBPB group showed a reduced risk of vertebral (adjusted hazard ratio (aHR) 0.83 [0.76-0.92]), hip (aHR 0.81 [0.74-0.89]), and distal radius (aHR 0.88 [0.78-0.99]) fractures compared to non-users. This relationship was represented by a time-dependent manner with fracture risk reduction in patients taking CBPB for 3-6 months (aHR 0.9 [0.83-0.99]) and ≥ 6 months (aHR 0.83 [0.78-0.89]), compared to those using CBPB for less than 3 months. Additionally, only the CBPB group had a lower risk of MACE, cardiac arrest, and ventricular arrhythmia than non-users. All phosphorus binder groups showed a reduced mortality risk compared to non-users. CONCLUSIONS: Our findings indicate that the using phosphate binders in ESKD patients is lowers the risk of osteoporotic fractures. Notably, those taking CBPB had a reduced risk without increasing cardiovascular events or mortality compared to non-users.

Management of serum phosphorus over a 1-year follow-up in patients on peritoneal dialysis prescribed sucroferric oxyhydroxide as part of routine care: a retrospective analysis.

BACKGROUND: Hyperphosphatemia is associated with increased morbidity and mortality in patients with end-stage kidney disease (ESKD). Whereas clinical and observational studies have demonstrated the effectiveness of sucroferric oxyhydroxide (SO) in controlling serum phosphorus (sP) in ESKD, data on the real-world impact of switching to SO in patients on peritoneal dialysis (PD) are limited. In this retrospective database analysis, we examine the impact of SO on sP management over a 1-year period among PD patients prescribed SO as part of routine clinical care. METHODS: We analyzed de-identified data from adults on PD in Fresenius Kidney Care clinics who were prescribed SO monotherapy between May 2018 and December 2019 as part of routine clinical management. Changes from baseline in sP levels, phosphate binder (PB) pill burden, and laboratory parameters were evaluated during the four consecutive 91-day intervals of SO treatment. RESULTS: The mean age of the 402 patients who completed 1 year of SO was 55.2 years at baseline, and they had been on PD for an average of 19.9 months. SO was initiated with no baseline PB recorded in 36.1% of patients, whereas the remaining 257 patients were switched to SO from sevelamer (39.7%), calcium acetate (30.4%), lanthanum (1.2%), ferric citrate (14.0%), or more than one PB (14.8%). Mean sP at baseline was 6.26 mg/dL. After being prescribed SO, the percentage of patients achieving sP ≤ 5.5 mg/dL increased from 32.1% (baseline) to 46.5-54.0% during the 1-year follow-up, whereas the mean number of PB pills taken per day decreased from 7.7 at baseline (among patients on a baseline PB) to 4.6 to 5.4. Serum phosphorus and PB pill burden decreased regardless of changes in residual kidney function over the 12-month period. Similar results were observed for the full cohort (976 patients who either completed or discontinued SO during the 1-year follow-up). CONCLUSIONS: Patients on PD who were prescribed SO as part of routine care for phosphorus management experienced significant reductions in SP and PB pills per day and improvements in sP target achievement, suggesting the effectiveness of SO on SP management with a concurrent reduction in pill burden.

Calcium mass balance in adults during single hemodialysis and hemodiafiltration treatments using lower calcium dialysate concentrations.

BACKGROUND: Debate continues as to the optimum hemodialysis (HD) dialysate calcium concentration. Although current guidelines advocate 1.25-1.5 mmol/L, some investigators have suggested these may cause calcium gains. As such we investigated whether using dialysate calcium of 1.25 mmol/L risked calcium gains, and whether there were differences between hemodiafiltration and high flux HD. METHODS: We continuously collect an aliquot of effluent dialysate during dialysis sessions, and calculated dialysis calcium mass balance by the difference between the amount of calcium delivered as fresh dialysate and that lost in effluent dialysate. RESULTS: We studied 106 stable outpatients, 64% male, mean age 64.4 ± 16.2 years, median dialysis vintage 32 (22-60) months. Most sessions (69%) used a 1.0 mmol/L calcium dialysate, with a median sessional loss of 13.7 (11.5-17.1) mmol, whereas using 1.25 mmol/L the median loss was 7.4 (4.9-10.1) mmol, but with 6.9% had a positive balance (p = 0.031 vs dialysate calcium 1.0 mmol/L). Most patients (85.8%) were treated by hemodiafiltration, but there was no difference in sessional losses (11.7 (8.4-15.8) vs 13.5 (8.1-16.8)) with high flux HD. Dialysis sessional calcium balance was associated with the use of lower dialysate calcium concentration (ß -19.5, 95% confidence limits (95%CL) -27.7 to -11.3, p < 0.001), and sessional duration (ß 0.07 (95% CL) 0.03-012, p = 0.002). CONCLUSION: Ideally, the choice of dialysate calcium should be individualized, but clinicians should be aware, that even when using a dialysate calcium of 1.25 mmol/L, some patients are at risk of a calcium gain during hemodiafiltration and high-flux hemodialysis.

Efficacy, tolerability, and safety of the oral phosphate binder VS-505 (AP301).

BACKGROUND: VS-505 (AP301), an acacia and ferric oxyhydroxide polymer, is a novel fiber-iron-based phosphate binder. This two-part phase 2 study evaluated the tolerability, safety, and efficacy of oral VS-505 administered three times daily with meals in treating hyperphosphatemia in chronic kidney disease (CKD) patients receiving maintenance hemodialysis (MHD). METHODS: In Part 1, patients received dose-escalated treatment with VS-505 2.25, 4.50, and 9.00 g/day for 2 weeks each, guided by serum phosphorus levels. In Part 2, patients received randomized, open-label, fixed-dosage treatment with VS-505 (1.50, 2.25, 4.50, or 6.75 g/day) or sevelamer carbonate 4.80 g/day for 6 weeks. The primary efficacy endpoint was the change in serum phosphorus. RESULTS: The study enrolled 158 patients (Part 1: 25; Part 2: 133), with 130 exposed to VS-505 in total. VS-505 was well tolerated. The most common adverse events were gastrointestinal disorders, mainly feces discolored (56%) and diarrhea (15%; generally during weeks 1‒2 of treatment). Most gastrointestinal disorders resolved without intervention, and none were serious. In Part 1, serum phosphorus significantly improved (mean change -2.0 mg/dL; 95% confidence interval -2.7, -1.4) after VS-505 dose escalation. In Part 2, serum phosphorus significantly and dose-dependently improved in all VS-505 arms, with clinically meaningful reductions with VS-505 4.50 and 6.75 g/day, and sevelamer carbonate 4.80 g/day (mean change -1.6 (-2.2, -1.0), -1.8 (-2.4, -1.2), and -1.4 (-2.2, -0.5) mg/dL, respectively). In both Parts, serum phosphorus reductions occurred within 1 week of VS-505 initiation, returning to baseline within 2 weeks of VS-505 discontinuation. CONCLUSION: VS-505, a novel phosphate binder, was well tolerated with a manageable safety profile, and effectively and dose-dependently reduced serum phosphorus in CKD patients with hyperphosphatemia receiving MHD. Clinical Trial registration number: NCT04551300.

Efficacy and Safety of Sucroferric Oxyhydroxide Compared with Sevelamer Carbonate in Chinese Dialysis Patients with Hyperphosphataemia: A Randomised, Open-Label, Multicentre, 12-Week Phase III Study.

INTRODUCTION: This study aimed to investigate the efficacy and safety of sucroferric oxyhydroxide (SFOH) versus sevelamer carbonate in controlling serum phosphorus (sP) in adult Chinese dialysis patients with hyperphosphataemia (sP >1.78 mmol/L). METHODS: Open-label, randomised (1:1), active-controlled, parallel group, multicentre, phase III study of SFOH and sevelamer at starting doses corresponding to 1,500 mg iron/day and 2.4 g/day, respectively, with 8-week dose titration and 4-week maintenance (NCT03644264). Primary endpoint was non-inferiority analysis of change in sP from baseline to week 12. Secondary endpoints included sP over time and safety. RESULTS: 415 patients were screened; 286 were enrolled and randomised (142 and 144 to SFOH and sevelamer, respectively). Mean (SD) baseline sP: 2.38 (0.57) and 2.38 (0.52) mmol/L, respectively. Mean (SD) change in sP from baseline to week 12: - 0.71 (0.60) versus -0.63 (0.52) mmol/L, respectively; difference (sevelamer minus SFOH) in least squares means (95% CI): 0.08 mmol/L (-0.02, 0.18) with the lower limit of 95% CI above the non-inferiority margin of -0.34 mmol/L. The SFOH group achieved target sP (1.13-1.78 mmol/L) earlier than the sevelamer group (56.5% vs. 32.8% at week 4) and with a lower pill burden (mean 3.7 vs. 9.1 tablets/day over 4 weeks of maintenance, respectively). Safety and tolerability of SFOH was consistent with previous studies, and no new safety signals were observed. CONCLUSION: SFOH effectively reduced sP from baseline and was non-inferior to sevelamer after 12 weeks of treatment but had a lower pill burden in Chinese dialysis patients with hyperphosphataemia; SFOH benefit-risk profile is favourable in Chinese patients.

Serum Phosphorus Management with Sucroferric Oxyhydroxide as a First-Line Phosphate Binder within the First Year of Hemodialysis.

INTRODUCTION: Sucroferric oxyhydroxide (SO), a non-calcium, chewable, iron-based phosphate binder (PB), effectively lowers serum phosphorus (sP) concentrations while reducing pill burden relative to other PBs. To date, SO studies have largely examined treatment-experienced, prevalent hemodialysis populations. We aimed to explore the role of first-line SO initiated during the first year of dialysis. METHODS: We retrospectively analyzed deidentified data from adults receiving in-center hemodialysis who were prescribed SO monotherapy within the first year of hemodialysis as part of routine clinical care. All patients continuing SO monotherapy for 12 months were included. Changes from baseline in sP, achievement of sP ≤5.5 and ≤4.5 mg/dL, and other laboratory parameters were analyzed quarterly for 1 year. RESULTS: The overall cohort included 596 patients, 286 of whom had a dialysis vintage ≤3 months. In the 3 months preceding SO initiation, sP rapidly increased (mean increases of 1.02 and 1.65 mg/dL in the overall cohort and incident cohort, respectively). SO treatment was associated with significant decreases in quarterly sP (mean decreases of 0.26-0.36; p < 0.0001 for each quarter and overall). While receiving SO, 55-60% of patients achieved sP ≤5.5 mg/dL and 21-24% achieved sP ≤4.5 mg/dL (p < 0.0001 for each quarter and overall vs. baseline). Daily PB pill burden was approximately 4 pills. Serum calcium concentrations increased and intact parathyroid hormone concentrations decreased during SO treatment (p < 0.0001 vs. baseline). CONCLUSIONS: Among patients on hemodialysis, initiating SO as a first-line PB resulted in significant reductions in sP while maintaining a relatively low PB pill burden.

Association between phosphate binder pill burden and mortality risk in patients on maintenance hemodialysis: a single-center cohort study with 7-year follow-up of 513 patients.

BACKGROUND: Dialysis patients often take multiple oral medications, leading to a high pill burden. Phosphate binders (PBs) account for a large proportion of this daily pill burden (DPB). The relationship between DPB and mortality risk remains unclear, and we hypothesized that this relationship might be influenced by the proportion of PBs to all medications. METHODS: We divided DPB into those derived from PBs and non-PB drugs and analyzed the association with mortality risk over a 7-year period in 513 chronic hemodialysis patients using a baseline model. RESULTS: The median (interquartile range) DPB from all drugs was 15.8 (11.2-21.0) pills/day/patient, and the median ratio of PB pills to all drug pills was 29.3 (13.7-45.9)% at baseline. During a median observation period of 5.2 years, 161 patients (31.4%) died. Kaplan-Meier analysis showed no significant difference in all-cause mortality between PB users and non-users. However, a significant survival advantage was observed in the highest tertile of DPB from PBs compared to the lowest tertile. Conversely, the highest tertile of DPB from non-PB drugs was associated with worse survival. Consequently, the highest tertile of the ratio of PBs to all pills was associated with better survival. This association remained significant even after adjusting for patient characteristics in the Cox proportional hazards model. However, when serum nutritional parameters were included as covariates, the significant association disappeared. CONCLUSIONS: Dialysis patients prescribed a higher rate of PB pills to all medications exhibited a lower mortality risk, possibly due to their better nutritional status.

Efficacy and Safety of Sevelamer Carbonate in Chinese Nondialysis Chronic Kidney Disease Patients with Hyperphosphatemia: A Randomized, Double-Blind, Parallel-Group Study.

Introduction: Previous studies suggested that sevelamer carbonate is well tolerated with a favorable efficacy and safety profile in both dialysis and nondialysis patients in Europe; however, the efficacy remains controversial, and few studies have examined sevelamer carbonate therapy in other ethnic nondialysis CKD patients. This study assessed the efficacy and safety of sevelamer carbonate in Chinese nondialysis CKD patients with hyperphosphatemia. Methods: The multicenter, randomized, double-blind, parallel-group, placebo-controlled, and phase 3 clinical trial enrolled 202 Chinese nondialysis CKD patients with serum phosphorus ≥1.78 mmol/L. Patients were randomly assigned 1:1 to receive sevelamer carbonate (2.4-12 g per day) or placebo for 8 weeks. The primary outcome was the change in serum phosphorous between baseline and week 8. Results: Totally 482 Chinese patients were screened and 202 were randomized (sevelamer carbonate, n = 101; placebo, n = 101). The mean serum phosphorous decreased significantly in patients treated with sevelamer carbonate compared with placebo (-0.22 ± 0.47 vs. 0.05 ± 0.44 mmol/L, p < 0.0001). Significantly (p < 0.0001), decreases of serum total cholesterol, low-density lipoprotein cholesterol, and calcium-phosphorus (Ca × P) product levels from baseline to week 8 were shown in sevelamer carbonate group compared with placebo group. Serum intact parathyroid hormone was not significantly changed in the sevelamer carbonate group (p = 0.83). Patients in the sevelamer carbonate group experienced similar adverse events as the placebo group. Conclusion: Sevelamer carbonate is an effective and well-tolerated phosphate binder in advanced nondialysis CKD Chinese patients with hyperphosphatemia.

The Role of Iron-Based Phosphate Binder in the Treatment of Hyperphosphatemia.

Hyperphosphatemia is a well-known complication of kidney disease. Phosphate binders are a mainstay treatment, but despite the existence of several phosphate binders, there is no one best approach to manage hyperphosphatemia. Phosphate binders are calcium-based, non-calcium- based, and others. While calcium-based phosphate binders are used frequently, they may cause hypercalcemia. Conversely, lanthanum carbonate and sevelamer were not linked to hypercalcemia but are costlier. The most recently developed class of phosphate binders is the ironbased ferric citrate and sucroferric oxyhydroxide. These have an important role in controlling phosphate levels due to their ability to lower the phosphate while concurrently providing iron sources. This review provides pharmacological profiles of different phosphate binders and their clinical usages, and further elaborates on their place in hyperphosphatemia management.

The Impact of Medical Nutrition Intervention on the Management of Hyperphosphatemia in Hemodialysis Patients with Stage 5 Chronic Kidney Disease: A Case Series.

The treatment and interdisciplinary management of patients with chronic kidney disease (CKD) continue to improve long-term outcomes. The medical nutrition intervention's role is to establish a healthy diet plan for kidney protection, reach blood pressure and blood glucose goals, and prevent or delay health problems caused by kidney disease. Our study aims to report the effects of medical nutrition therapy-substituting foods rich in phosphorus-containing additives with ones low in phosphates content on phosphatemia and phosphate binders drug prescription in stage 5 CKD patients with hemodialysis. Thus, 18 adults with high phosphatemia levels (over 5.5 mg/dL) were monitored at a single center. Everyone received standard personalized diets to replace processed foods with phosphorus additives according to their comorbidities and treatment with prosphate binder drugs. Clinical laboratory data, including dialysis protocol, calcemia, and phosphatemia, were evaluated at the beginning of the study, after 30 and 60 days. A food survey was assessed at baseline and after 60 days. The results did not show significant differences between serum phosphate levels between the first and second measurements; thus, the phosphate binders' initial doses did not change. After 2 months, phosphate levels decreased considerably (from 7.322 mg/dL to 5.368 mg/dL); therefore, phosphate binder doses were diminished. In conclusion, medical nutrition intervention in patients with hemodialysis significantly reduced serum phosphate concentrations after 60 days. Restricting the intake of processed foods containing phosphorus additives-in particularized diets adapted to each patient's comorbidities-and receiving phosphate binders represented substantial steps to decrease phosphatemia levels. The best results were significantly associated with life expectancy; at the same time, they showed a negative correlation with the dialysis period and participants' age.

Real-World Phosphate Binder Use among Dialysis-Dependent Patients with CKD.

INTRODUCTION: For patients with chronic kidney disease (CKD), the need for phosphate binder (PB) treatment peaks at onset of dialysis. This real-world study assessed rates of PB utilization and switching in patients with dialysis-dependent CKD (DD-CKD). METHODS: We identified patients with PB utilization among those with prevalent DD-CKD using 2018-2019 Medicare Parts A/B/D data. Patients were assigned to cohorts based on primary (most frequently used) PB among calcium acetate, ferric citrate, lanthanum carbonate, sevelamer (hydrochloride and carbonate), sucroferric oxyhydroxide. We measured proportion of patients who were adherent (proportion of days covered >80%) and persistent (patients whose last 90 days of outpatient dialysis reported PB use). Net switching rates were calculated as the difference between switches to and from the primary agent. RESULTS: We identified 136,912 patients with PB use. Proportion of patients adherent ranged from 63.8% (lanthanum carbonate) to 67.7% (sevelamer) and persistent from 85.1% (calcium acetate) to 89.5% (ferric citrate). Most patients (73%) used the same PB throughout the study. Overall, 20.5% of patients experienced one switch and 2.3% two or more. Positive net switching rates were observed for ferric citrate, sucroferric oxyhydroxide, and lanthanum carbonate (2-10%) but negative for sevelamer and calcium acetate (-2% to -7%). CONCLUSION: Adherence and persistence rates were low with slight variation across PBs. Net positive switching occurred for ferric citrate, sucroferric oxyhydroxide, and lanthanum carbonate. Further studies are needed to determine the reasons for these findings and could identify opportunities for better control of phosphate levels among patients with CKD.

Interaction and mechanisms in the phosphate-binding of iron(oxyhydr)oxide core-shell nanoparticles.

HYPOTHESIS: The high binding affinity of iron(oxyhydr)oxides for phosphate has recently been used in medicine to treat hyperphosphatemia, an abnormally elevated phosphate concentration in the blood. For iron(oxyhydr)oxide nanoparticles, the composition of the organic shell has a more significant influence on their interaction with phosphate than is often assumed. This study shows different mechanisms in phosphate binding, using the example of two similar new phosphate-binding agents. EXPERIMENTS: We characterized the phosphate-binding behavior of two iron(oxyhydr)oxide-based nanomaterials with similar composition and particle properties and investigated their binding mechanisms by spectroscopic methods. FINDINGS: For the often prescribed Velphoro, we demonstrated a phosphate binding capacity of>210 mg/g. A similar active ingredient named C-PAM binds over 573 mg/g. Spectroscopic measurements highlighted differences in the binding mechanism. While Velphoro binds phosphate via surface complexation independent of pH and adsorbent concentration, C-PAM shows a strong concentration dependence. At low concentrations, phosphate is bound via complexation reactions. The iron(oxyhydr)oxide structure was dissolved at higher phosphate concentrations and formed various iron phosphate species. The substances behave differently upon interaction with phosphate, although being very similar in composition and crystal structure. Thus, we demonstrated a crucial influence of the ligands in the shell on the binding mechanism.

Effect of the phosphate binder sucroferric oxyhydroxide in dialysis patients on endogenous calciprotein particles, inflammation, and vascular cells.

BACKGROUND: Calciprotein particles (CPPs), colloidal mineral-protein nanoparticles, have emerged as potential mediators of phosphate toxicity in dialysis patients, with putative links to vascular calcification, endothelial dysfunction and inflammation. We hypothesized that phosphate binder therapy with sucroferric oxyhydroxide (SO) would reduce endogenous CPP levels and attenuate pro-calcific and pro-inflammatory effects of patient serum towards human vascular cells in vitro. METHODS: This secondary analysis of a randomised controlled crossover study compared the effect of 2-week phosphate binder washout with high-dose (2000 mg/day) and low-dose (250 mg/day) SO therapy in 28 haemodialysis patients on serum CPP levels, inflammatory cytokine/chemokine arrays and human aortic smooth muscle cell (HASMC) and coronary artery endothelial cell (HCAEC) bioassays. RESULTS: In our cohort (75% male, 62 ± 12 years) high-dose SO reduced primary (amorphous) and secondary (crystalline) CPP levels {-62% [95% confidence interval (CI) -76 to -44], P < .0001 and -38% [-62 to -0.14], P < .001, respectively} compared with washout. Nine of 14 plasma cytokines/chemokines significantly decreased with high-dose SO, with consistent reductions in interleukin-6 (IL-6) and IL-8. Exposure of HASMC and HCAEC cultures to serum of SO-treated patients reduced calcification and markers of activation (IL-6, IL-8 and vascular cell adhesion protein 1) compared with washout. Serum-induced HASMC calcification and HCAEC activation was ameliorated by removal of the CPP-containing fraction from patient sera. Effects of CPP removal were confirmed in an independent cohort of chronic kidney disease patients. CONCLUSIONS: High-dose SO reduced endogenous CPP formation in dialysis patients and yielded serum with attenuated pro-calcific and inflammatory effects in vitro.

A real-world analysis of the influence of age on maintenance hemodialysis patients: managing serum phosphorus with sucroferric oxyhydroxide as part of routine clinical care.

OBJECTIVE: Despite the growing number of elderly hemodialysis patients, the influence of age on nutritional parameters, serum phosphorus (sP), and use of phosphate-binder (PB) medications has not been well characterized. We aimed to describe age-related differences in patient characteristics in a large, real-world cohort of maintenance hemodialysis patients, and to examine the impact of age on sP management with sucroferric oxyhydroxide (SO). METHODS: We retrospectively analyzed de-identified data from 2017 adult, in-center hemodialysis patients who switched from another PB to SO monotherapy as part of routine clinical care. Changes in baseline PB pill burden, sP levels, and nutritional and dialytic clearance parameters were assessed across varying age groups through 6 months. RESULTS: At baseline, older patients had lower mean sP, serum albumin, and pre-dialysis weights compared with younger patients. Prescription of SO was associated with a 62% increase in the proportion of patients achieving sP ≤ 5.5 mg/dl and a 42% reduction in daily pill burden. The proportion of patients achieving sP ≤ 5.5 mg/dl after transitioning to SO increased by 113, 96, 68, 77, 61, 37 and 40% among those aged 19-29, 30-39, 40-49, 50-59, 60-69, 70-79, and ≥ 80 years, respectively. CONCLUSIONS: Older patients had worse nutritional parameters, lower pill burden, and lower sP at baseline versus younger counterparts. Prescription of SO was associated with improved sP control and reduced pill burden across all ages.

Phosphate-Trapping Liposomes for Long-Term Management of Hyperphosphatemia.

Hyperphosphatemia is a typical complication of end-stage renal disease, characterized by elevated and life-threatening serum phosphate levels. Hemodialysis does not enable sufficient clearance of phosphate, due to slow cell-to-plasma kinetics of phosphate ions; moreover, dietary restrictions and conventional treatment with oral phosphate binders have low success rates, together with adverse effects. Here, we developed a new concept of phosphate-trapping liposomes, to improve and prolong the control over serum phosphate levels. We designed liposomes modified with polyethylene glycol and encapsulated with the phosphate binder ferric citrate (FC liposomes). These liposomes were found to trap phosphate ions in their inner core, and thereby lower free phosphate ion concentrations in solution and in serum. The FC liposomes showed higher phosphate binding ability as phosphate concentrations increased. Moreover, these liposomes showed a time-dependent increase in uptake of phosphate, up to 25 h in serum. Thus, our findings demonstrate effective long-term phosphate trapping by FC liposomes, indicating their potential to reduce serum phosphate toxicity and improve current management of hyperphosphatemia.

Reversal Of Arterial Disease by modulating Magnesium and Phosphate (ROADMAP-study): rationale and design of a randomized controlled trial assessing the effects of magnesium citrate supplementation and phosphate-binding therapy on arterial stiffness in moderate chronic kidney disease.

BACKGROUND: Arterial stiffness and calcification propensity are associated with high cardiovascular risk and increased mortality in chronic kidney disease (CKD). Both magnesium and phosphate are recognized as modulators of vascular calcification and chronic inflammation, both features of CKD that contribute to arterial stiffness. In this paper, we outline the rationale and design of a randomized controlled trial (RCT) investigating whether 24 weeks of oral magnesium supplementation with or without additional phosphate-binding therapy can improve arterial stiffness and calcification propensity in patients with stage 3-4 CKD. METHODS: In this multi-center, placebo-controlled RCT, a total of 180 participants with an estimated glomerular filtration rate of 15 to 50 ml/min/1.73 m2 without phosphate binder therapy will be recruited. During the 24 weeks intervention, participants will be randomized to one of four intervention groups to receive either magnesium citrate (350 mg elemental magnesium/day) or placebo, with or without the addition of the phosphate binder sucroferric oxyhydroxide (1000 mg/day). Primary outcome of the study is the change of arterial stiffness measured by the carotid-femoral pulse wave velocity over 24 weeks. Secondary outcomes include markers of calcification and inflammation, among others calcification propensity (T50) and high-sensitivity C-reactive protein. As explorative endpoints, repeated 18F-FDG and 18F-NaF PET-scans will be performed in a subset of participants (n = 40). Measurements of primary and secondary endpoints are performed at baseline, 12 and 24 weeks. DISCUSSION: The combined intervention of magnesium citrate supplementation and phosphate-lowering therapy with sucroferric oxyhydroxide, in stage 3-4 CKD patients without overt hyperphosphatemia, aims to modulate the complex and deregulated mineral metabolism leading to vascular calcification and arterial stiffness and to establish to what extent this is mediated by T50 changes. The results of this combined intervention may contribute to future early interventions for CKD patients to reduce the risk of CVD and mortality. TRIAL REGISTRATION: Netherlands Trial Register, NL8252 (registered December 2019), EU clinical Trial Register 2019-001306-23 (registered November 2019).

Seguridad y efectividad del oxihidróxido sucroférrico en pacientes españoles en diálisis: subanálisis del estudio VERIFIE / Safety and effectiveness of sucroferric oxyhydroxide in Spanish dialysis patients: A sub-analysis of the VERIFIE study

Antecedentes y objetivo: En este estudio presentamos los resultados del subgrupo de pacientes españoles del estudio VERIFIE, primer estudio postautorización prospectivo que evalúa la seguridad y efectividad a largo plazo del oxihidróxido sucroférrico (OHS) en pacientes en diálisis con hiperfosfatemia durante la práctica clínica habitual. Pacientes y métodos: Se incluyeron pacientes en hemodiálisis y diálisis peritoneal con indicación de tratamiento con OHS. La duración del seguimiento fue de 12 a 36 meses desde el inicio del tratamiento con OHS. Las variables primarias de seguridad fueron la incidencia de reacciones adversas a medicamentos, eventos médicos de interés especial y variaciones en los parámetros del hierro. La efectividad del OHS se evaluó mediante el cambio en los niveles de fósforo sérico. Resultados: Se reclutaron 286 pacientes y se analizaron los datos de 282. De estos 282 pacientes, 161 (57,1%) abandonaron el estudio de manera prematura y un 52,5% recibieron tratamiento concomitante con otros captores de fósforo. Un 35,1% reportaron reacciones adversas a medicamentos y la mayoría fueron de tipo gastrointestinal (77,1%) y de intensidad leve/moderada (83,7%). Un 14,2% de los pacientes presentaron eventos médicos de interés especial, de los que el 93,7% fueron leves/moderados. Se observó un incremento de la ferritina (386,66 vs. 447,55ng/mL; p=0,0013) y saturación de la transferrina (28,07 vs. 30,34%; p=0,043) desde el inicio hasta la última visita. Los niveles de fósforo sérico disminuyeron progresivamente desde 5,69mg/dL al inicio hasta 4,84mg/dL en la última visita (p<0,0001), aumentando la proporción de pacientes con niveles de fósforo≤5,5mg/dL un 32,2%, y con una dosis diaria media de 1,98 comprimidos/día. (AU)

Background and aims: In this study, we show the results of the subset of Spanish patients of the VERIFIE study, the first post-marketing study assessing the long-term safety and effectiveness of sucroferric oxyhydroxide (SFOH) in patients with hyperphosphatemia undergoing dialysis during clinical practice. Patients and methods: Patients undergoing hemodialysis and peritoneal dialysis with indication of SFOH treatment were included. Follow-up duration was 12–36 months after SFOH initiation. Primary safety variables were the incidence of adverse drug reactions, medical events of special interest, and variations in iron-related parameters. SFOH effectiveness was evaluated by the change in serum phosphorus levels. Results: A total of 286 patients were recruited and data from 282 were analyzed. Among those 282 patients, 161 (57.1%) withdrew the study prematurely and 52.5% received concomitant treatment with other phosphate binders. Adverse drug reactions were observed in 35.1% of patients, the most common of which were gastrointestinal disorders (77.1%) and mild/moderate in severity (83.7%). Medical events of special interest were reported in 14.2% of patients, and 93.7% were mild/moderate. An increase in ferritin (386.66ng/mL vs 447.55ng/mL; P=.0013) and transferrin saturation (28.07% vs 30.34%; P=.043) was observed from baseline to the last visit. Serum phosphorus levels progressively decreased from 5.69mg/dL at baseline to 4.84mg/dL at the last visit (P<.0001), increasing by 32.2% the proportion of patients who achieved serum phosphorus levels≤5.5mg/dL, with a mean daily SFOH dose of 1.98pills/day. (AU)

Administration of the probiotic Lactiplantibacillus paraplantarum is effective in controlling hyperphosphatemia in 5/6 nephrectomy rat model.

AIMS: Several studies have linked gut microbes to human diseases. Most of the mechanisms by which lactic acid bacteria have beneficial effects on the human body are related to immune modulation. Controlled studies of the ability of lactic acid bacteria to absorb phosphorus directly from the intestine and thereby control serum phosphorus level in in vivo uremic animal models are limited. MATERIALS AND METHODS: We screened lactic acid bacteria living in Korean fermented foods to identify those that absorb the most phosphorus and noted Lactiplantibacillus paraplantarum KCCM 11826P. The mechanism through which better intracellular absorption of phosphorus occurs in this strain was studied using genomic DNA sequencing. After the strain was administered to 5/6 nephrectomized rats for 6 weeks, it was observed whether hyperphosphatemia had improved. KEY FINDINGS: The L. paraplantarum KCCM 11826P strain has a polyP gene cluster; thus, it absorbs phosphorus better than other bacteria and can suppress strains that produce indole. Supplementing the diets of 5/6 nephrectomized rats with this L. paraplantarum strain significantly decreased serum phosphate level (by 22 %) and reduced blood indoxyl sulphate concentration (by 40 %) compared with vehicle treatment. SIGNIFICANCE: These results suggest that Lactiplantibacillus preparations can be used for multiple purposes, such as the removal of phosphorus and uremic toxins from patients with chronic kidney disease (CKD). This study also demonstrates the novel concept of a probiotic phosphate binder.

Evaluation of cerium oxide as a phosphate binder using 5/6 nephrectomy model rat.

BACKGROUND: The number of chronic kidney disease (CKD) patients continues to increase worldwide. CKD patients need to take phosphate binders to manage serum phosphorus concentrations. Currently, several types of phosphate binder, including lanthanum carbonate, are used. However, they each have disadvantages. METHODS: In this study, we evaluated cerium oxide as a new phosphate binder in vitro and in vivo. First, cerium oxide was mixed with phosphoric acid at pH 2.5 or 7.0, and residual phosphoric acid was measured by absorption photometry using colorimetric reagent. Second, cerium oxide was fed to 5/6 nephrectomy model rats (5/6Nx), a well-known renal damage model. All rats were measured food intake, water intake, feces volume, and urine volume, and collected serum and urine were analyzed for biochemical markers. RESULTS: Cerium oxide can adsorb phosphate at acidic and neutral pH, while lanthanum carbonate, which is a one of popular phosphate binder, does not dissolve at neutral pH. Cerium oxide-treatment reduced serum phosphate concentrations of 5/6Nx rats without an increase in serum alanine transaminase levels that would indicate hepatotoxicity, and cerium oxide-treatment maintained serum creatinine and blood urea nitrogen levels, while those of normal 5/6Nx rats increased slightly. CONCLUSIONS: These results suggest that cerium oxide can be a potential phosphate binder. Decreased body weight gain and increased water intake and urine volume in 5/6Nx rats were thought to be an effect of nephrectomy because these changes did not occur in sham operation rats. Additional investigations are needed to evaluate the longer-term safety and possible accumulation of cerium oxide in the body.

Clinical Factors Associated with Serum Magnesium Concentration in Patients Undergoing Peritoneal Dialysis: A Single-Center Observational Study.

Purpose: Magnesium (Mg) is an essential element that is associated with various physiological functions, such as maintenance of blood pressure, muscle contraction, and nerve function. In patients undergoing hemodialysis, hypomagnesemia is associated with cardiovascular and all-cause mortality. However, in patients undergoing peritoneal dialysis (PD), clinical factors associated with Mg have not been fully investigated. Patients and Methods: Clinical factors including anthropometric data, comorbidities, laboratory data, medications, and dialysis methods were collected from the medical records of patients undergoing PD. The associations of these factors with the serum Mg concentration were investigated by univariate and multivariate analyses. Results: Sixty patients undergoing PD were investigated. The univariate analysis showed that the serum Mg concentration was significantly associated with treatment by hybrid PD (daily PD + once-weekly hemodialysis) (ß = 0.264, P = 0.04), administration of phosphate binders (ß = 0.294, P = 0.02), the serum C-reactive protein concentration (ß = -0.318, P = 0.01), the serum potassium (K) concentration (ß = 0.451, P < 0.01), and the serum intact parathormone concentration (ß = -0.333, P = 0.01). The multivariate analysis using these factors showed an independent association between the serum Mg and K concentrations (ß = 0.333, P = 0.01). Conclusion: The serum Mg concentration was independently associated with the serum K concentration in patients undergoing PD.