Effect of MCI-196 on serum phosphate and cholesterol levels in haemodialysis patients with hyperphosphataemia: a double-blind, randomized, placebo-controlled study

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.

Comparative Efficacy and Safety of Phosphate Binders in Hyperphosphatemia Patients With Chronic Kidney Disease

BACKGROUND

In this study, we coordinated a network meta-analysis to establish the efficacy and safety of different agents used in the treatment of hyperphosphatemia patients with chronic kidney disease.

METHODS

PubMed, CNKI, and Embase were systematically searched to retrieve relevant studies. Outcomes were presented by mean differences, odds ratios, and corresponding 95% credible intervals for continuous outcomes and binary outcomes, respectively. Each therapy was ranked according to the value of surface under the cumulative ranking curve. Consistencies between direct and indirect comparisons were assessed with a node-splitting plot.

RESULTS

In terms of efficacy end points (including levels of serum phosphate, serum calcium, serum intact parathyroid hormone, and serum calcium × phosphorus product), all 7 kinds of agents outperformed or performed at least equally to placebo, with iron-based phosphate-binding agents being potentially the most effective. As for safety end points (including mortality, adverse events, and all-cause discontinuation), almost all agents were equivalent in term of mortality and all-cause discontinuation except in the comparison between iron-based phosphate-binding agents and placebo. Meanwhile, iron-based phosphate-binding agents colestilan and nicotinic acid performed poorly compared with placebo in terms of adverse events. Furthermore, iron-based phosphate-binding agents were potentially the safest agents followed sequentially by calcium-based phosphate-binding agents and placebo.

CONCLUSION

Iron-based phosphate-binding agents were the preferable agents when considering efficacy and safety simultaneously.

Advances in pharmacotherapy for hyperphosphatemia in renal disease

INTRODUCTION

Hyperphosphatemia in chronic kidney disease (CKD) is considered as an independent risk factor for surrogate clinical end points like vascular calcification (VC) and bone disease, or hard clinical outcomes like cardiovascular events. Various treatment options are available for phosphate removal or reduction. Calcium-based phosphate binders (CBB) with their possible positive calcium balance became culprits for progressive VC and increased mortality risk. Non-calcium-based binders (NCBB) treatment allowed a comparable control of hyperphosphatemia with a lower risk of hypercalcemia and a slower progression of VC. Recent data have shown a 22% risk reduction in all-cause mortality with NCBB compared to CBB treatment. The appropriate timing of phosphate binder initiation in CKD patients is still unclear. Recent reports in patients with CKD stages 3b-4 showed increased VC progression when actively treated compared to placebo and a positive calcium, but no negative phosphate balance.

AREAS COVERED

This review discusses the advantages and disadvantages of the pharmacological options to treat hyperphosphatemia.

EXPERT OPINION

The use of phosphate binders is essential in preventing morbidity and mortality in dialysis patients. The choice of phosphate binder takes into account CKD stage, the presence of other components of CKD-mineral and bone disorders, concomitant therapies and drug side-effect profile.

Effect of colestilan on serum phosphorus in dialysis patients: A meta-analysis of the literature

AIM

To evaluate the efficacy and safety of colestilan as a phosphorus binder in dialysis patients, we performed a meta-analysis of randomized controlled trials.

METHODS

We retrieved studies that compared colestilan with placebo in the treatment of dialysis patients from Medline, EMBASE, the Cochrane Library and conference proceedings.

RESULTS

Four studies were included. The treatment durations ranged from 2 to 12 weeks, median 7.5 weeks. Compared with placebo group, colestilan significantly decreased serum phosphorus (WMD, -0.22 mmol/L; 95% CI, -0.33 to -0.12, P < 0.0001), calcium phosphorus product (WMD, -0.70 mmol(2) /L(2) ; 95% CI, -1.06 to -0.35, P = 0.0001), intact PTH (WMD, -5.37 pmol/L; 95% CI, -8.38 to -2.36, P = 0.0005) and LDL cholesterol (WMD, -0.78 mmol/L; 95% CI, -0.85 to -0.71, P < 0.00001). There was no significant difference in serum calcium between the two groups. Colestilan therapy increased gastrointestinal complaints significantly (OR = 4.07, 95% CI: 3.06-6.53, P < 0.00001). Sensitivity analysis was performed by excluding studies with Jadad score of three or 3 g/day colestilan, the results did not change.

CONCLUSIONS

Short-term administration of colestilan is effective for the treatment of hyperphosphataemia in dialysis patients. Long-term effectiveness and safety needs to be evaluated.

Cardiovascular mortality in chronic kidney disease patients: potential mechanisms and possibilities of inhibition by resin-based phosphate binders

Cardiovascular mortality has been considered as the most important risk associated with chronic kidney disease. The mechanisms underlying this include inflammation, poor control of serum phosphate, high serum calcium, increased calcification of the arteries and cardiac valves, hyperlipidemia, diabetes, severe anemia, uric acid accumulation and others. Elevated phosphate levels have been strongly associated with increased mortality, thus phosphate-binding drugs have long been used to control the increase serum phosphate levels. However, phosphate-binding drugs differ considerably and recently numerous publications suggest differences between agents in the effects on overall mortality. The resin-based phosphate binders, comprising sevelamer and colestilan, not only reduce serum phosphate but also do not raise serum calcium. In addition, they reduce serum LDL-C, inflammation, uric acid and high Hba1c values. These differences suggest that not all phosphate binders may be equal in the context of cardiovascular mortality in this patient population.

Colestilan for the treatment of hyperphosphatemia in chronic kidney disease patients on dialysis

Chronic kidney disease in the later stages poses many treatment challenges. Hyperphosphatemia is one that is well-known and is often linked to increased cardiovascular morbidity/mortality. Currently, a number of phosphate binders are available that act to conserve serum phosphate at normal or near normal levels. However, it is the overall profile of all binders that needs to be taken into account and the risks and the potential benefits associated with each agent must be balanced when selecting a particular phosphate binder. It is known that calcium-based binders, although effective phosphate binders, may lead to hypercalcemia and/or positive calcium balance and cardiovascular calcification. One, new non-calcium phosphate binder, recently approved in Europe, is colestilan. Colestilan possesses a range of properties that may afford further advantages over simply reducing serum phosphate. This review assesses the pharmacology and clinical data of colestilan used to treat hyperphosphatemia in chronic kidney disease stage 5 patients on dialysis. The article was written based on literature searches using PubMed to find articles published on phosphate binders or colestilan over the last 10 years.

Lipid, blood pressure and kidney update 2013

The year 2013 proved to be very exciting as far as landmark trials and new guidelines in the field of lipid disorders, blood pressure and kidney diseases. Among these are the International Atherosclerosis Society Global Recommendations for the Management of Dyslipidemia, European Society of Cardiology (ESC)/European Society of Hypertension Guidelines for the Management of Arterial Hypertension, American Diabetes Association Clinical Practice Recommendations, the Kidney Disease: Improving Global Outcomes Clinical Practice Guidelines for Managing Dyslipidemias in Chronic Kidney Disease (CKD) Patients, the American College of Cardiology/American Heart Association Guideline on the Treatment of Blood Cholesterol to Reduce Atherosclerotic Cardiovascular Risk in Adults, the Joint National Committee Expert Panel (JNC 8) Evidence-Based Guideline for the Management of High Blood Pressure in Adults, the American Society of Hypertension/International Society of Hypertension Clinical Practice Guidelines for the Management of Hypertension in the Community, the American College of Physicians Clinical Practice Guideline on Screening, Monitoring, and Treatment of Stage 1-3 CKD and many important trials presented among others during the ESC Annual Congress in Amsterdam and the American Society of Nephrology Annual Meeting--Kidney Week in Atlanta, GA. The paper is an attempt to summarize the most important events and reports in the mentioned areas in the passing year.

The effects of colestilan versus placebo and sevelamer in patients with CKD 5D and hyperphosphataemia: a 1-year prospective randomized study

BACKGROUND

This study compared the effects of short-term titrated colestilan (a novel non-absorbable, non-calcium, phosphate binder) with placebo, and evaluated the safety and efficacy of colestilan over 1 year compared with sevelamer, in patients with chronic kidney disease (CKD) 5D.

METHODS

This prospective multicentre study comprised a 4-week phosphate binder washout period, a 16-week short-term, flexible-dose, treatment period (including a 4-week placebo-controlled withdrawal period) and a 40-week extension treatment phase.

RESULTS

At Week 16 (the end of the 4-week placebo-controlled withdrawal period), serum phosphorus level was 0.43 mmol/L (1.32 mg/dL) lower with colestilan than placebo (P < 0.001; primary end point). Serum LDL-C level was also lower with colestilan than with placebo (P < 0.001). Both colestilan and sevelamer produced significant reductions from baseline in serum phosphorus levels (P < 0.001), maintained for 1 year, and the proportion of patients achieving target levels of ≤1.78 mmol/L (5.5 mg/dL) or ≤1.95 mmol/L (6.0 mg/dL) at study end were similar (65.3 and 73.3%, respectively, for colestilan, and 66.9 and 77.4%, respectively, for sevelamer). Serum calcium level remained stable in the colestilan group but tended to increase slightly in the sevelamer group (end-of-study increase of 0.035 mmol/L over baseline). Both binders produced similar reductions from baseline in LDL-C level (P < 0.001), and responder rates after 1 year, using a target of <1.83 mmol/L (70 mg/dL) or <2.59 mmol/L (100 mg/dL) were similar in both groups (50.7 and 85.3% for colestilan and 54.0 and 80.6% for sevelamer). Colestilan was generally well tolerated.

CONCLUSIONS

Colestilan is effective and safe for the treatment of hyperphosphataemia in patients with CKD 5D, and affords similar long-term phosphorus and cholesterol reductions/responder rates to sevelamer.

Hyperparathyroidism in chronic kidney disease patients: an update on current pharmacotherapy

INTRODUCTION

Secondary hyperparathyroidism is the most common abnormalities of mineral metabolism in chronic kidney disease (CKD), which causes bone disease and vascular calcification, leading to increased risk of mortality.

AREAS COVERED

The aim of this review is to provide an overview of pharmacological therapies for secondary hyperparathyroidism, based on current understanding of the disease.

EXPERT OPINION

The initial event in the pathogenesis of secondary hyperparathyroidism is the phosphorus overload per nephron that lead to the secretion of a new phosphaturic hormone, fibroblast growth factor 23 from the bone. Such an abnormality develops very early in CKD, even without hyperphosphatemia. When hyperphosphatemia develops, phosphate binders are prescribed in many CKD patients. Non-calcium containing binders are gaining popularity because of less risk of excess calcium load; however, no specific superiority in patient-level outcomes has been fully established yet. For the direct control of parathyroid hormone secretion, cinacalcet hydrochloride has become widespread in addition to vitamin D receptor activators. As adverse events related to these therapeutic agents occur occasionally, however, and better adherence is one of the most important determinants of the benefits of the drugs, fewer adverse events as well as more potent therapeutic effects should be aimed in the development of new agents in future.

Management of hyperphosphataemia in chronic kidney disease-challenges and solutions

Hyperphosphataemia is a clinical consequence of the advanced stages of chronic kidney disease (CKD). Considerable evidence points to a role of hyperphosphataemia in the pathogenesis of CKD-associated cardiovascular (CV) complications, including vascular calcification, and with increased all-cause and CV mortality. These observations place management of hyperphosphataemia at the centre of CKD treatment. Although our increased understanding of the physiological role of FGF-23 may provide a long-term alternative biomarker of phosphate load and underlying disease progression, regular determination of serum phosphate is currently the most frequently used parameter to evaluate phosphate load in clinical practice. This review considers the challenges physicians and patients face in trying to control hyperphosphataemia. Amongst these are the limitations of dietary phosphate restriction, giving rise to the need for phosphate binder therapy to maintain serum phosphate control. Once the decision to use phosphate binders has been made, considerations include the relative efficacy, different potential side effects and pill burden associated with various phosphate binders. Although a number of phosphate binders are available, adherence poses a major obstacle to effective treatment. This emphasizes that further improvements to phosphate binder therapy can be made. Evaluation of novel agents and their potential role in the clinic should continue.