Three Times Weekly Dosing of Daprodustat versus Conventional Epoetin for Treatment of Anemia in Hemodialysis Patients: ASCEND-TD: A Phase 3 Randomized, Double-Blind, Noninferiority Trial.

BACKGROUND AND OBJECTIVES: Daprodustat is a hypoxia-inducible factor prolyl hydroxylase inhibitor (HIF-PHI) being investigated for the treatment of anemia of CKD. In this noninferiority trial, we compared daprodustat administered three times weekly with epoetin alfa (epoetin) in patients on prevalent hemodialysis switching from a prior erythropoiesis-stimulating agent (ESA). DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Patients on hemodialysis with a baseline hemoglobin of 8-11.5 g/dl receiving an ESA were randomized 2:1 to daprodustat three times weekly (n=270) or conventional epoetin (n=137) for 52 weeks. Dosing algorithms aimed to maintain hemoglobin between 10 and 11 g/dl. The primary end point was mean change in hemoglobin from baseline to the average during the evaluation period (weeks 28-52). The principal secondary end point was average monthly intravenous iron dose. Other secondary end points included BP and hemoglobin variability. RESULTS: Daprodustat three times weekly was noninferior to epoetin for mean change in hemoglobin (model-adjusted mean treatment difference [daprodustat-epoetin], -0.05; 95% confidence interval, -0.21 to 0.10). During the evaluation period, mean (SD) hemoglobin values were 10.45 (0.55) and 10.51 (0.85) g/dl for daprodustat and epoetin groups, respectively. Responders (defined as mean hemoglobin during the evaluation period in the analysis range of 10 to 11.5 g/dl) were 80% in the daprodustat group versus 64% in the epoetin group. Proportionately fewer participants in the daprodustat group versus the epoetin group had hemoglobin values either below 10 g/dl or above 11.5 g/dl during the evaluation period. Mean monthly intravenous iron use was not significantly lower with daprodustat versus epoetin. The effect on BP was similar between groups. The percentage of treatment-emergent adverse events was similar between daprodustat (75%) and epoetin (79%). CONCLUSIONS: Daprodustat was noninferior to epoetin in hemoglobin response and was generally well tolerated. CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER: Anemia Studies in Chronic Kidney Disease: Erythropoiesis via a Novel Prolyl Hydroxylase Inhibitor Daprodustat-Three Times Weekly Dosing in Dialysis (ASCEND-TD), NCT03400033.

Groundhog Day: research without old data and old references.

BACKGROUND: The use of older data and references is becoming increasingly disfavored for publication. A myopic focus on newer research risks losing sight of important research questions already addressed by now-invisible older studies. This creates a 'Groundhog Day' effect as illustrated by the 1993 movie of this name in which the protagonist has to relive the same day (Groundhog Day) over and over and over within a world with no memory of it. This article examines the consequences of the recent preference for newer data and references in current publication practices and is intended to stimulate new consideration of the utility of selected older data and references for the advancement of scientific knowledge. METHODS: Examples from the literature are used to exemplify the value of older data and older references. To illustrate the recency of references published in original medical research articles in a selected sample of recent academic medical journals, original research articles were examined in recent issues in selected psychiatry, medicine, and surgery journals. RESULTS: The literature examined reflected this article's initial assertion that journals are emphasizing the publication of research with newer data and more recent references. CONCLUSIONS: The current valuation of newer data above older data fails to appreciate the fact that new data eventually become old, and that old data were once new. The bias demonstrated in arbitrary policies pertaining to older data and older references can be addressed by instituting comparable treatment of older and newer data and references.

Iron Treatment Strategies in Dialysis-Dependent CKD.

Iron deficiency is common in patients on chronic dialysis, and most require iron-replacement therapy. In addition to absolute iron deficiency, many patients have functional iron deficiency as shown by a suboptimal response to the use of erythropoietin-stimulating agents. Both absolute and functional iron-deficiency anemia have been shown to respond to intravenous (IV) iron replacement. Although parenteral iron is an efficacious method and superior to standard doses of oral iron in patients on hemodialysis, there are ongoing safety concerns about repeated exposure potentially enhancing infection risk and cardiovascular disease. Each IV iron product is composed of an iron core with a carbohydrate shell. The avidity of iron binding and the type of carbohydrate shell play roles in the safe maximal dose and the frequency and severity of acute infusion reactions. All IV iron products are taken up into the reticuloendothelial system where the shell is metabolized and the iron is stored within tissue ferritin or exported to circulating transferrin. IV iron can be given as large intermittent doses (loading therapy) or in smaller doses at frequent intervals (maintenance dosing regimen). Limited trial data and observational data suggest that a maintenance dosing regimen is more efficacious and possibly safer than loading therapy. There is no consensus regarding the preferred method of iron repletion in patients on peritoneal dialysis, although small studies comparing oral and parenteral iron regimens in these patients have shown the latter to be more efficacious. Use of IV iron in virtually all hemodialysis and many peritoneal dialysis patients remains the standard of care.

A randomized trial of iron isomaltoside 1000 versus oral iron in non-dialysis-dependent chronic kidney disease patients with anaemia.

BACKGROUND: Iron deficiency anaemia is common in patients with non-dialysis-dependent chronic kidney disease (NDD-CKD) and is often treated with oral or intravenous (IV) iron therapy. This trial compared the efficacy and safety of IV iron isomaltoside 1000 (Monofer®) and oral iron in NDD-CKD patients with renal-related anaemia. METHODS: The trial was a Phase III open-label, comparative, multicentre, non-inferiority trial conducted in 351 iron-deficient NDD-CKD patients, randomized 2:1 to either iron isomaltoside 1000 (Group A) or iron sulphate administered as 100 mg elemental oral iron twice daily (200 mg daily) for 8 weeks (Group B). The patients in Group A were randomized into A1 (infusion of max. 1000 mg single doses over 15 min) and A2 (bolus injections of 500 mg over 2 min). A modified Ganzoni formula was used to calculate IV iron need. The primary end point was change in haemoglobin concentrations from baseline to Week 4. RESULTS: Iron isomaltoside 1000 was both non-inferior to oral iron at Week 4 (P < 0.001) and sustained a superior increase in haemoglobin from Week 3 until the end of the study at Week 8 (P = 0.009 at Week 3). The haemoglobin response was more pronounced with iron isomaltoside 1000 doses ≥1000 mg (P < 0.05). Serum-ferritin and transferrin saturation concentrations were also significantly increased with IV iron. Adverse drug reactions were observed in 10.5% in the iron isomaltoside 1000 group and 10.3% in the oral iron group. More patients treated with oral iron sulphate withdrew from the study due to adverse events (4.3 versus 0.9%, P = 0.2). CONCLUSIONS: Iron isomaltoside 1000 was more efficacious than oral iron for increase in haemoglobin and proved to be well tolerated at the tested dose levels in NDD-CKD patients.

A randomized, open-label trial of iron isomaltoside 1000 (Monofer®) compared with iron sucrose (Venofer®) as maintenance therapy in haemodialysis patients.

BACKGROUND: Iron deficiency anaemia is common in patients with chronic kidney disease, and intravenous iron is the preferred treatment for those on haemodialysis. The aim of this trial was to compare the efficacy and safety of iron isomaltoside 1000 (Monofer®) with iron sucrose (Venofer®) in haemodialysis patients. METHODS: This was an open-label, randomized, multicentre, non-inferiority trial conducted in 351 haemodialysis subjects randomized 2:1 to either iron isomaltoside 1000 (Group A) or iron sucrose (Group B). Subjects in Group A were equally divided into A1 (500 mg single bolus injection) and A2 (500 mg split dose). Group B were also treated with 500 mg split dose. The primary end point was the proportion of subjects with haemoglobin (Hb) in the target range 9.5-12.5 g/dL at 6 weeks. Secondary outcome measures included haematology parameters and safety parameters. RESULTS: A total of 351 subjects were enrolled. Both treatments showed similar efficacy with >82% of subjects with Hb in the target range (non-inferiority, P = 0.01). Similar results were found when comparing subgroups A1 and A2 with Group B. No statistical significant change in Hb concentration was found between any of the groups. There was a significant increase in ferritin from baseline to Weeks 1, 2 and 4 in Group A compared with Group B (Weeks 1 and 2: P < 0.001; Week 4: P = 0.002). There was a significant higher increase in reticulocyte count in Group A compared with Group B at Week 1 (P < 0.001). The frequency, type and severity of adverse events were similar. CONCLUSIONS: Iron isomaltoside 1000 and iron sucrose have comparative efficacy in maintaining Hb concentrations in haemodialysis subjects and both preparations were well tolerated with a similar short-term safety profile.

Considerations and challenges in defining optimal iron utilization in hemodialysis.

Trials raising concerns about erythropoiesis-stimulating agents, revisions to their labeling, and changes to practice guidelines and dialysis payment systems have provided strong stimuli to decrease erythropoiesis-stimulating agent use and increase intravenous iron administration in recent years. These factors have been associated with a rise in iron utilization, particularly among hemodialysis patients, and an unprecedented increase in serum ferritin concentrations. The mean serum ferritin concentration among United States dialysis patients in 2013 exceeded 800 ng/ml, with 18% of patients exceeding 1200 ng/ml. Although these changes are broad based, the wisdom of these practices is uncertain. Herein, we examine influences on and trends in intravenous iron utilization and assess the clinical trial, epidemiologic, and experimental evidence relevant to its safety and efficacy in the setting of maintenance dialysis. These data suggest a potential for harm from increasing use of parenteral iron in dialysis-dependent patients. In the absence of well powered, randomized clinical trials, available evidence will remain inadequate for making reliable conclusions about the effect of a ubiquitous therapy on mortality or other outcomes of importance to dialysis patients. Nephrology stakeholders have an urgent obligation to initiate well designed investigations of intravenous iron in order to ensure the safety of the dialysis population.

Update on intravenous iron choices.

PURPOSE OF REVIEW: Iron deficiency is a major factor in the prevalence and severity of anemia in patients with chronic kidney disease (CKD). We review the pathophysiology impairing normal intestinal iron absorption in CKD and compare the characteristics of newer intravenous (i.v.) iron agents to the longstanding i.v. iron products in the market. RECENT FINDINGS: The newer iron products, ferumoxytol, ferric carboxymaltose, and iron isomaltoside, more avidly bind iron, minimizing the release of labile iron during infusions, thus permitting large dose infusions. These irons also have more complex carbohydrate shells than their predecessors, which may also diminish reactions. Newer agents can be routinely administered at higher single doses, in as little as 15 min, with an acceptable safety profile. SUMMARY: Newer i.v. iron products permit the rapid, and sometimes complete, repletion of iron-deficient patients with a single dose. However, further studies examining the long-term risks and benefits of i.v. iron repletion are needed.

The health-related quality of life was not improved by targeting higher hemoglobin in the Normal Hematocrit Trial.

The Normal Hematocrit Trial (NHT) was the largest trial of epoetin randomizing 1265 hemodialysis patients with cardiac disease to lower (9-11 g/dl) or higher (13-15 g/dl) hemoglobin (Hgb), hypothesizing that higher Hgb would reduce mortality, and improve survival and quality of life. The trial was terminated early, and a 1998 publication reported that targeting higher hematocrit levels led to an insignificant increase in the primary end points (death or myocardial infarct), or risk ratio 1.3, 95% confidence interval (CI), 0.9-1.90, but the P-value was not given, and all-cause death risk was not reported. A higher target reportedly did not increase hospitalization rates, but did significantly improve the 'physical function' domain of quality of life. Comparing the 1996 Food and Drug Administration (FDA)-filed clinical trial report to the 1998 publication, however, found several discrepancies. Among these, the 1998 article reported interim trial results with only the adjusted CI but did not state that the unadjusted CIs were 99.912th percentile, and despite being a secondary end point, reported only the association of achieved Hgb with higher quality of life score. Randomization to the higher target had actually increased the risk for the primary end point (risk ratio 1.28, 95% CI=1.06-1.56; P=0.0112; 99.92% CI=0.92-1.78), the risk of death (risk ratio 1.27, 95% CI=1.04-1.54), non-access thrombotic events (P=0.041), and hospitalization rate (P=0.04), while 'physical function' did not improve (P=0.88). Hence, disclosure of these results in the 1998 publication or access to the FDA-filed report on the NHT in the late 1990s would likely have led to earlier concerns about epoetin safety and greater doubts about its benefits.

Hepcidin: clinical utility as a diagnostic tool and therapeutic target.

Iron is essential for life, yet excessive iron can damage tissues and organs. To prevent iron deficiency and overload, iron balance is regulated by the hormone hepcidin. Hepcidin levels increase in response to iron sufficiency, decreasing intestinal iron absorption and inhibiting release of iron from stores and macrophages. Iron deficiency lowers hepcidin, leading to enhanced iron absorption and mobilization of iron from stores. Hepcidin is also increased by inflammation, and has a major role in the anemia of chronic disease. Chronic kidney disease (CKD) is associated with increased hepcidin levels, and this likely contributes to the incidence and severity of anemia, and resistance to erythropoiesis-stimulating agents (ESAs). Elevated hepcidin contributes to the dysregulation of iron homeostasis in CKD. In patients with CKD, although parenteral iron in CKD can bypass some of the iron-blocking effects of hepcidin, free iron and iron stores increase, anemia is only partially corrected, and ESA dose requirements remain significantly higher than physiological replacement. Agents that lower hepcidin or inhibit its actions may be effective strategies to restore normal iron homeostasis, and overcome anemia of chronic kidney disease. We review the regulation of hepcidin, its role in CKD-related anemia, and discuss the potential for hepcidin as a clinical marker, and several investigational methods to lower hepcidin for treatment of anemia in CKD.

The future of intravenous iron in nephrology.

Management of anaemia in chronic kidney disease (CKD) patients can be difficult and expensive. The recently completed Trial to Reduce Cardiovascular Events with Aranesp Therapy (TREAT), the largest double-blinded trial of erythropoiesis-stimulating agents (ESA) treatment in CKD to date, provides us with a wealth of new information on the natural history of anaemia in Stage 3 and 4 CKD and the risks and benefits of use of ESAs. This section will discuss some of the TREAT trial results in the context of other recent studies of ESAs and intravenous iron in CKD patients. It will also review applying those results when choosing anaemia goals for an individual, and determining if iron therapy might improve anaemia.

Iron supplementation to treat anemia in patients with chronic kidney disease.

Iron deficiency is prevalent in patients with chronic kidney disease (CKD), and use of oral and intravenous iron in patients with CKD who do not require dialysis might obviate or delay the need for treatment with eythropoiesis-stimulating agents (ESAs). Patients on hemodialysis have lower intestinal iron absorption, greater iron losses, and require greater iron turnover to maintain the ESA-driven red cell mass than do healthy individuals. In these patients, intravenous iron reduces ESA dose requirements and increases the likelihood of maintaining levels of hemoglobin within the desired range. Oral iron is inferior to intravenous iron in patients on hemodialysis, in part because elevated serum levels of hepcidin prevent intestinal absorption of iron. Increased levels of hepcidin also impair the normal recycling of iron through the reticuloendothelial system. Levels of serum ferritin and transferrin saturation below 450 pmol/l and 20%, respectively are indicative of iron deficiency, but values above the normal range lack diagnostic value in patients with CKD on dialysis. The availability of various iron preparations and new developments in delivering iron should enable adequate provision of iron to patients with CKD. This Review examines the efficacy, safety and use of iron supplementation therapy for the treatment of anemia in patients with CKD.

Intra-individual variability in serum hepcidin precludes its use as a marker of iron status in hemodialysis patients.

An accurate assessment of iron status in dialysis patients is important because both anemia and overtreatment with erythropoiesis-stimulating agents are associated with poor clinical outcomes. We have previously shown that both analytical and intra-individual (biological) variability in serum ferritin limits its utility as a proxy for iron stores in patients in this setting. As hepcidin is a direct regulator of iron status, its measurement might be useful for monitoring patients with iron dysregulation. We assessed short-term intra-individual variation of serum hepcidin in 28 patients with stable chronic kidney disease on hemodialysis. The intra-individual variability for serum hepcidin ranged from 9-79% during an initial 2-week to 12-85% over a 6-week period. The concentration of serum hepcidin was significantly correlated with serum C-reactive protein levels over the 6-week study period. Hence, significant intra-individual variability of hepcidin is likely dependent on short-term fluctuations in the inflammatory state. Thus, our results suggest that short-term measurement of serum hepcidin should not be used to guide clinical decisions regarding management of iron status in chronic hemodialysis patients.