Anaemia in CKD - treatment standard.

Anaemia is one of the most common complications of chronic kidney disease (CKD), having a significant impact on quality-of-life, and is also associated with a number of adverse clinical outcomes. Its pathogenesis is multifactorial, caused largely by an inadequate production of erythropoietin from the diseased kidneys, with iron deficiency, inflammation, shortened red cell lifespan, and enhanced blood loss also being contributory factors. The management of this condition was transformed in the late-1980's by the advent of recombinant human erythropoietin (epoetin) manufactured in Chinese hamster ovary cells, and treatment paradigms have developed over the last three decades, largely focusing on a combination of epoetin or its analogues (erythropoiesis-stimulating agents; ESAs) along with iron supplementation, often administered intravenously due to increased hepcidin levels limiting iron absorption from the gut. Indeed, in patients with early CKD and iron deficiency, iron per se may be sufficient to improve the anaemia, delaying the need for ESA therapy. Other causes of anaemia should be excluded and corrected (if possible) before resorting to treatment with ESAs and iron. More recently, the HIF-prolyl hydroxylase inhibitors have entered the therapeutic arena; these are orally-active agents that upregulate endogenous erythropoietin production as well as a number of iron-regulatory genes which may also enhance erythropoiesis. The latter drugs are highly efficacious, and may have advantages in inflammatory conditions causing resistance to conventional ESA therapy, but concerns exist regarding their safety, particularly in the longer term. This article reviews the current standards of treatment, as well as recent novel developments in the management of anaemia in CKD.

A Randomized Trial of Intravenous Iron Supplementation and Exercise on Exercise Capacity in Iron-Deficient Nonanemic Patients With CKD.

Introduction: Patients with chronic kidney disease (CKD) are often iron deficient, even when not anemic. This trial evaluated whether iron supplementation enhances exercise capacity of nonanemic patients with CKD who have iron-deficiency. Methods: Prospective, multicenter double-blind randomized controlled trial of nondialysis patients with CKD and iron-deficiency but without anemia (Hemoglobin [Hb] >110 g/l). Patients were assigned 1:1 to intravenous (IV) iron therapy, or placebo. An 8-week exercise program commenced at week 4. The primary outcome was the mean between-group difference in 6-minute walk test (6MWT) at 4 weeks. Secondary outcomes included 6MWT at 12 weeks, transferrin saturation (TSAT), serum ferritin (SF), Hb, renal function, muscle strength, functional capacity, quality of life, and adverse events at baseline, 4 weeks, and at 12 weeks. Mean between-group differences were analyzed using analysis of covariance models. Results: Among 75 randomized patients, mean (SD) age for iron therapy (n = 37) versus placebo (n = 38) was 54 (16) versus 61 (12) years; estimated glomerular filtration rate (eGFR) (34 [12] vs. 35 [11] ml/min per 1.73 m2], TSAT (23 [12] vs. 21 [6])%; SF (57 [64] vs. 62 [33]) µg/l; Hb (122.4 [9.2] vs. 127 [13.2] g/l); 6MWT (384 [95] vs. 469 [142] meters) at baseline, respectively. No significant mean between-group difference was observed in 6MWT distance at 4 weeks. There were significant increases in SF and TSAT at 4 and 12 weeks (P < 0.02), and Hb at 12 weeks (P = 0.009). There were no between-group differences in other secondary outcomes and no adverse events attributable to iron therapy. Conclusion: This trial did not demonstrate beneficial effects of IV iron therapy on exercise capacity at 4 weeks. A larger study is needed to confirm if IV iron is beneficial in nondialysis patients with CKD who are iron-deficient.

Intravenous ferric carboxymaltose for iron repletion following acute heart failure in patients with and without diabetes: a subgroup analysis of the randomized AFFIRM-AHF trial.

BACKGROUND: In AFFIRM-AHF, treatment of iron deficiency with intravenous ferric carboxymaltose (FCM) reduced the risk of heart failure (HF) hospitalization and improved quality of life (QoL) vs placebo in patients stabilized following an acute HF (AHF) episode, with no effect on cardiovascular (CV) death. Diabetes and iron deficiency frequently accompany AHF. This post hoc analysis explored the effects of diabetes on outcomes in AFFIRM-AHF patients. METHODS: Patients were stratified by diabetes yes/no at baseline. The effects of FCM vs placebo on primary (total HF hospitalizations and CV death) and secondary (total CV hospitalizations and CV death; CV death; total HF hospitalizations; time to first HF hospitalization or CV death; and days lost due to HF hospitalizations or CV death) endpoints at Week 52 and change vs baseline in disease-specific QoL (12-item Kansas City Cardiomyopathy Questionnaire [KCCQ-12]) at Week 24 were assessed by subgroup. For each endpoint, the interaction between diabetes status and treatment outcome was explored. RESULTS: Of 1108 AFFIRM-AHF patients, 475 (FCM: 231; placebo: 244) had diabetes and 633 (FCM: 327; placebo: 306) did not have diabetes. Patients with diabetes were more commonly male (61.5% vs 50.9%), with a higher frequency of ischemic HF etiology (57.9% vs 39.0%), prior HF history (77.7% vs 66.5%), and comorbidities (including previous myocardial infarction [49.3% vs 32.9%] and chronic kidney disease [51.4% vs 32.4%]) than those without diabetes. The annualized event rate/100 patient-years with FCM vs placebo for the primary endpoint was 66.9 vs 80.9 in patients with diabetes (rate ratio [RR]: 0.83, 95% CI 0.58-1.81) and 51.3 vs 66.9 in patients without diabetes (RR: 0.77, 95% CI 0.55-1.07), with no significant interaction between diabetes status and treatment effect (pinteraction = 0.76). Similar findings were observed for secondary outcomes. Change from baseline in KCCQ-12 overall summary score was numerically greater with FCM vs placebo at almost all time points in both subgroups, with no interaction between diabetes and treatment effect at Week 24. CONCLUSIONS: The clinical and QoL benefits observed with intravenous FCM in patients with iron deficiency following stabilization from an AHF episode are independent of diabetes status. Trial registration Clinicaltrials.gov, NCT02937454 (registered 10.18.2016).

Ferric Carboxymaltose in Iron-Deficient Patients with Hospitalized Heart Failure and Reduced Kidney Function.

BACKGROUND: Reduced kidney function is common among patients with heart failure. In patients with heart failure and/or kidney disease, iron deficiency is an independent predictor of adverse outcomes. In the AFFIRM-AHF trial, patients with acute heart failure with iron deficiency treated with intravenous ferric carboxymaltose demonstrated reduced risk of heart failure hospitalization, with improved quality of life. We aimed to further characterize the impact of ferric carboxymaltose among patients with coexisting kidney impairment. METHODS: The double-blind, placebo-controlled AFFIRM-AHF trial randomized 1132 stabilized adults with acute heart failure (left ventricular ejection fraction <50%) and iron deficiency. Patients on dialysis were excluded. The primary end point was a composite of total heart failure hospitalizations and cardiovascular death during the 52-week follow-up period. Additional end points included cardiovascular hospitalizations, total heart failure hospitalizations, and days lost to heart failure hospitalizations or cardiovascular death. For this subgroup analysis, patients were stratified according to baseline eGFR. RESULTS: Overall, 60% of patients had an eGFR <60 ml/min per 1.73 m 2 (the lower eGFR subgroup). These patients were significantly older, more likely to be female and to have ischemic heart failure, and had higher baseline serum phosphate levels and higher rates of anemia. For all end points, event rates were higher in the lower eGFR group. In the lower eGFR group, the annualized event rates for the primary composite outcome were 68.96 and 86.30 per 100 patient-years in the ferric carboxymaltose and placebo arms, respectively (rate ratio, 0.76; 95% confidence interval, 0.54 to 1.06). The treatment effect was similar in the higher eGFR subgroup (rate ratio, 0.65; 95% confidence interval, 0.42 to 1.02; Pinteraction = 0.60). A similar pattern was observed for all end points ( Pinteraction > 0.05). CONCLUSIONS: In a cohort of patients with acute heart failure, left ventricular ejection fraction <50%, and iron deficiency, the safety and efficacy of ferric carboxymaltose were consistent across a range of eGFR values. CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER: Study to Compare Ferric Carboxymaltose With Placebo in Patients With Acute Heart Failure and Iron Deficiency (Affirm-AHF), NCT02937454 .

Association Between Hemoglobin Levels and Efficacy of Intravenous Ferric Carboxymaltose in Patients With Acute Heart Failure and Iron Deficiency: An AFFIRM-AHF Subgroup Analysis.

BACKGROUND: Iron deficiency, with or without anemia, is an adverse prognostic factor in heart failure (HF). In AFFIRM-AHF (a randomized, double-blind placebo-controlled trial comparing the effect of intravenous ferric carboxymaltose on hospitalizations and mortality in iron-deficient subjects admitted for acute heart failure), intravenous ferric carboxymaltose (FCM), although having no significant effect on the primary end point, reduced the risk of HF hospitalization (hHF) and improved quality of life versus placebo in iron-deficient patients stabilized after an acute HF (AHF) episode. These prespecified AFFIRM-AHF subanalyses explored the association between hemoglobin levels and FCM treatment effects. METHODS: AFFIRM-AHF was a multicenter, double-blind, randomized, placebo-controlled trial of FCM in hospitalized AHF patients with iron deficiency. Patients were stratified by baseline hemoglobin level (<12 versus ≥12 g/dL). In each subgroup, the primary composite (total hHF and cardiovascular death) and secondary (total hHF; total cardiovascular hospitalizations and cardiovascular death; time to cardiovascular death, and time to first/days lost due to hHF or cardiovascular death) outcomes were assessed with FCM versus placebo at week 52. Sensitivity analyses using the World Health Organization anemia definition (hemoglobin level <12 g/dL [women] or <13 g/dL [men]) were performed, among others. RESULTS: Of 1108 AFFIRM-AHF patients, 1107 were included in these subanalyses: 464 (FCM group, 228; placebo group, 236) had a hemoglobin level <12 g/dL, and 643 (FCM, 329; placebo, 314) had a hemoglobin level ≥12 g/dL. Patients with a hemoglobin level <12 g/dL were older (mean, 73.7 versus 69.1 years), with more frequent previous HF (75.0% versus 68.7%), serum ferritin <100 µg/L (75.4% versus 68.1%), and transferrin saturation <20% (87.9% versus 81.4%). For the primary outcome, annualized event rates per 100 patient-years with FCM versus placebo were 71.1 and 73.6 (rate ratio, 0.97 [95% CI, 0.66-1.41]), respectively, and 48.5 versus 72.9 (RR, 0.67 [95% CI, 0.48-0.93]) in the hemoglobin levels <12 and ≥12 g/dL subgroups, respectively. No significant interactions between hemoglobin subgroup and treatment effect were observed for primary (Pinteraction=0.15) or secondary outcomes. Changes from baseline in hemoglobin, serum ferritin and transferrin saturation were significantly greater with FCM versus placebo in both subgroups between weeks 6 and 52. Findings were similar using the World Health Organization definition for anemia. CONCLUSIONS: The effects of intravenous FCM on outcomes in iron-deficient patients stabilized after an AHF episode, including improvements in iron parameters over time, did not differ between patients with hemoglobin levels <12 and ≥12 g/dL. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT02937454.

The ASCEND-NHQ randomized trial found positive effects of daprodustat on hemoglobin and quality of life in patients with non-dialysis chronic kidney disease.

The ASCEND-NHQ trial evaluated the effects of daprodustat on hemoglobin and the Medical Outcomes Study 36-item Short Form Survey (SF-36) Vitality score (fatigue) in a multicenter, randomized, double-blind, placebo-controlled trial. Adults with chronic kidney disease (CKD) stages 3-5, hemoglobin 8.5-10.0 g/dl, transferrin saturation 15% or more, and ferritin 50 ng/ml or more without recent erythropoiesis-stimulating agent use were randomized (1:1) to oral daprodustat or placebo to achieve and maintain target hemoglobin of 11-12 g/dl over 28 weeks. The primary endpoint was the mean change in hemoglobin between baseline and the evaluation period (Weeks 24-28). Principal secondary endpoints were proportion of participants with a 1 g/dl or more increase in hemoglobin and mean change in the Vitality score between baseline and Week 28. Outcome superiority was tested (1-sided alpha level of 0.025). Overall, 614 participants with non-dialysis-dependent CKD were randomized. The adjusted mean change in hemoglobin from baseline to the evaluation period was greater with daprodustat (1.58 vs 0.19 g/dl). The adjusted mean treatment difference (AMD) was significant at 1.40 g/dl (95% confidence interval 1.23, 1.56). A significantly greater proportion of participants receiving daprodustat showed a 1 g/dl or greater increase in hemoglobin from baseline (77% vs 18%). The mean SF-36 Vitality score increased by 7.3 and 1.9 points with daprodustat and placebo, respectively; a clinically and statistically significant 5.4 point Week 28 AMD increase. Adverse event rates were similar (69% vs 71%); relative risk 0.98, (95% confidence interval 0.88, 1.09). Thus, in participants with CKD stages 3-5, daprodustat resulted in a significant increase in hemoglobin and improvement in fatigue without an increase in the overall frequency of adverse events.

Predictors of quality of life in patients within the first year of commencing haemodialysis based on baseline data from the PIVOTAL trial and associations with the study outcomes.

BACKGROUND: Impaired quality of life is common in patients with end-stage kidney disease. We report the baseline quality of life measures in participants from the PIVOTAL randomized controlled trial and the potential relationship with the primary outcome (all-cause mortality, myocardial infarction, stroke, and heart failure hospitalisation), and associations with key baseline characteristics. METHODS: This was a post hoc analysis of 2141 patients enrolled in the PIVOTAL trial. Quality of life was measured using EQ5D index, Visual Analogue Scale, and the KD-QoL [Physical Component Score and Mental Component Score]. RESULTS: Mean baseline EQ5D index and visual analogue scale scores were 0.68 and 60.7 and 33.7 (Physical Component Score) and 46.0 (Mental Component Score), respectively. Female sex, higher Body Mass Index, diabetes mellitus, history of myocardial infarction, stroke or heart failure were associated with significantly worse EQ5D index and visual analogue scale. Higher C-reactive protein levels and lower transferrin saturation were associated with worse quality of life. Haemoglobin was not an independent predictor of quality of life. A lower transferrin saturation was an independent predictor of worse physical component score. A higher C-reactive protein level was associated with most aspects of worse quality of life. Impaired functional status was associated with mortality. CONCLUSION: Quality of life was impaired in patients starting haemodialysis. A higher C-reactive protein level level was a consistent independent predictor of the majority of worse quality of life. Transferrin saturation ≤ 20% was associated with worse physical component score of quality of life. Baseline quality of life was predictive of all-cause mortality and the primary outcome measure. EUDRACT REGISTRATION NUMBER: 2013-002267-25.

Feasibility of randomized controlled trials and long-term implementation of interventions: Insights from a qualitative process evaluation of the PEDAL trial.

Introduction: A multi-site randomized controlled trial was carried out between 2015 and 2019 to evaluate the impacts on quality of life of an intradialytic exercise programme for people living with chronic kidney disease. This included a qualitative process evaluation which gave valuable insights in relation to feasibility of the trial and of the intervention in the long-term. These can inform future clinical Trial design and evaluation studies. Methods: A constructivist phenomenological approach underpinned face-to-face, semi-structured interviews. Purposive recruitment ensured inclusion of participants in different arms of the PEDAL Trial, providers with different roles and trial team members from seven Renal Units in five study regions. Following ethical review, those willing took part in one interview in the Renal Unit. Audio-recorded interviews were transcribed (intelligent verbatim) and inductively thematically analyzed. Results: Participants (n = 65) (Intervention arm: 26% completed; 13% who did not; Usual care arm: 13%; 46% women; 54% men; mean age 60 year) and providers (n = 39) were interviewed (23% PEDAL Trial team members). Three themes emerged: (1) Implementing the Intervention; (2) Implementing the trial; and (3) Engagement of the clinical team. Explanatory theory named "the Ideal Scenario" was developed, illustrating complex interactions between different aspects of intervention and trial implementation with the clinical context. This describes characteristics likely to optimize trial feasibility and intervention sustainability in the long-term. Key aspects of this relate to careful integration of the trial within the clinical context to optimize promotion of the trial in the short-term and engagement and ownership in the long-term. Strong leadership in both the clinical and trial teams is crucial to ensure a proactive and empowering culture. Conclusion: Novel explanatory theory is proposed with relevance for Implementation Science. The "Ideal Scenario" is provided to guide trialists in pre-emptive and ongoing risk analysis relating to trial feasibility and long-term intervention implementation. Alternative study designs should be explored to minimize the research-to-practice gap and optimize the likelihood of informative findings and long-term implementation. These might include Realist Randomized Controlled Trials and Hybrid Effectiveness-Implementation studies.

Regional Variation of Erythropoiesis-Stimulating Agent Hyporesponsiveness in the Global Daprodustat Dialysis Study (ASCEND-D).

INTRODUCTION: Hyporesponsiveness to erythropoiesis-stimulating agents (ESAs) affects 10-15% of the chronic dialysis population. We explored baseline characteristics and predictors of ESA hyporesponsiveness in a global randomized cardiovascular outcomes study comparing an investigational hypoxia-inducible factor prolyl hydroxylase inhibitor (HIF-PHI), daprodustat, with conventional ESA treatment. METHODS: ASCEND-D (NCT02879305) recruited 2,964 chronic dialysis patients receiving ESA treatment (standardized to weekly intravenous [IV] epoetin) who were iron replete at baseline. The primary ESA hyporesponsiveness definition was an ESA Resistance Index (ERI, ESA units/kg/week/hemoglobin g/L) ≥2 or IV standardized ESA dose ≥450 units/kg/week. Predictors of ESA hyporesponsiveness were determined using a multivariable regression model. Alternative hyporesponder definitions were explored. RESULTS: Using the primary definition, 354 (12%) patients were ESA hyporesponsive. Geographic region, notably Latin America, lower baseline body mass index and transferrin saturation, younger age, lower albumin concentration, and a higher baseline IV iron dose were identified as strongly associated (p < 0.001) with ESA hyporesponsiveness. Additional predictors of ESA hyporesponsiveness included female sex (p = 0.010), history of heart failure (p = 0.035), longer dialysis vintage (p = 0.077), smoking status (p = 0.247), aspirin use (p = 0.121), and angiotensin-converting enzyme inhibitor/angiotensin receptor blocker use (p = 0.214). CONCLUSION: This is the first global HIF-PHI study to report prespecified definitions and predictors of ESA hyporesponsiveness. While most of the predictors identified in our study have been previously reported, geographic region stands out as an unexpected finding, meriting further investigation.

Step-Wise Management of Anemia in Patients With Chronic Kidney Disease in Primary Care: Qualitative Study.

INTRODUCTION: Anemia is common in chronic kidney disease (CKD) and is associated with increased cardiovascular risk and reduced quality of life, but is often sub-optimally managed. Most patients are managed in primary care alongside other comorbidities. Interventions to improve the management of anemia in CKD in this setting are needed. METHODS: We conducted a qualitative study to evaluate how an audit-based education (ABE) intervention might improve the management of anemia in CKD. We explored outcomes that would be relevant to practitioners and patients, that exposed variation of practice from National Institute for Health and Care Excellence (NICE) guidelines, and whether the intervention was feasible and acceptable. RESULTS: Practitioners (n = 5 groups) and patients (n = 7) from 4 London general practices participated in discussions. Practitioners welcomed the evidence-based step-wise intervention. However, prescribing erythropoiesis-stimulating agents (ESAs) was felt to be outside of their scope of practice. There was a gap between NICE guidance and clinical practice in primary care. Iron studies were not well understood and anemia management was often conservative or delayed. Patients were often unaware of having CKD, and were more concerned about their other comorbidities, but largely trusted their GPs to manage them appropriately. CONCLUSIONS: The first steps of the intervention were welcomed by practitioners, but they expressed concerns about independently prescribing ESAs. Renal physicians and GPs could develop shared care protocols for ESA use in primary care. There is scope to improve awareness of renal anemia, and enhance knowledge of guideline recommendations; and our intervention should be modified accordingly.

High-dose intravenous iron reduces myocardial infarction in patients on haemodialysis.

AIMS: To investigate the effect of high-dose iron vs. low-dose intravenous (IV) iron on myocardial infarction (MI) in patients on maintenance haemodialysis. METHODS AND RESULTS: This was a pre-specified analysis of secondary endpoints of the Proactive IV Iron Therapy in Hemodialysis Patients trial (PIVOTAL) randomized, controlled clinical trial. Adults who had started haemodialysis within the previous year, who had a ferritin concentration <400 µg per litre and a transferrin saturation <30% were randomized to high-dose or low-dose IV iron. The main outcome measure for this analysis was fatal or non-fatal MI. Over a median of 2.1 years of follow-up, 8.4% experienced a MI. Rates of type 1 MIs (3.2/100 patient-years) were 2.5 times higher than type 2 MIs (1.3/100 patient-years). Non-ST-elevation MIs (3.3/100 patient-years) were 6 times more common than ST-elevation MIs (0.5/100 patient-years). Mortality was high after non-fatal MI (1- and 2-year mortality of 40% and 60%, respectively). In time-to-first event analyses, proactive high-dose IV iron reduced the composite endpoint of non-fatal and fatal MI [hazard ratio (HR) 0.69, 95% confidence interval (CI) 0.52-0.93, P = 0.01] and non-fatal MI (HR 0.69, 95% CI 0.51-0.93; P = 0.01) when compared with reactive low-dose IV iron. There was less effect of high-dose IV iron on recurrent MI events than on the time-to-first event analysis. CONCLUSION: In total, 8.4% of patients on maintenance haemodialysis had an MI over 2 years. High-dose compared to low-dose IV iron reduced MI in patients receiving haemodialysis. EUDRACT REGISTRATION NUMBER: 2013-002267-25.

Intravenous ferric derisomaltose in patients with heart failure and iron deficiency in the UK (IRONMAN): an investigator-initiated, prospective, randomised, open-label, blinded-endpoint trial.

BACKGROUND: For patients with heart failure, reduced left ventricular ejection fraction and iron deficiency, intravenous ferric carboxymaltose administration improves quality of life and exercise capacity in the short-term and reduces hospital admissions for heart failure up to 1 year. We aimed to evaluate the longer-term effects of intravenous ferric derisomaltose on cardiovascular events in patients with heart failure. METHODS: IRONMAN was a prospective, randomised, open-label, blinded-endpoint trial done at 70 hospitals in the UK. Patients aged 18 years or older with heart failure (left ventricular ejection fraction ≤45%) and transferrin saturation less than 20% or serum ferritin less than 100 µg/L were eligible. Participants were randomly assigned (1:1) using a web-based system to intravenous ferric derisomaltose or usual care, stratified by recruitment context and trial site. The trial was open label, with masked adjudication of the outcomes. Intravenous ferric derisomaltose dose was determined by patient bodyweight and haemoglobin concentration. The primary outcome was recurrent hospital admissions for heart failure and cardiovascular death, assessed in all validly randomly assigned patients. Safety was assessed in all patients assigned to ferric derisomaltose who received at least one infusion and all patients assigned to usual care. A COVID-19 sensitivity analysis censoring follow-up on Sept 30, 2020, was prespecified. IRONMAN is registered with ClinicalTrials.gov, NCT02642562. FINDINGS: Between Aug 25, 2016, and Oct 15, 2021, 1869 patients were screened for eligibility, of whom 1137 were randomly assigned to receive intravenous ferric derisomaltose (n=569) or usual care (n=568). Median follow-up was 2·7 years (IQR 1·8-3·6). 336 primary endpoints (22·4 per 100 patient-years) occurred in the ferric derisomaltose group and 411 (27·5 per 100 patient-years) occurred in the usual care group (rate ratio [RR] 0·82 [95% CI 0·66 to 1·02]; p=0·070). In the COVID-19 analysis, 210 primary endpoints (22·3 per 100 patient-years) occurred in the ferric derisomaltose group compared with 280 (29·3 per 100 patient-years) in the usual care group (RR 0·76 [95% CI 0·58 to 1·00]; p=0·047). No between-group differences in deaths or hospitalisations due to infections were observed. Fewer patients in the ferric derisomaltose group had cardiac serious adverse events (200 [36%]) than in the usual care group (243 [43%]; difference -7·00% [95% CI -12·69 to -1·32]; p=0·016). INTERPRETATION: For a broad range of patients with heart failure, reduced left ventricular ejection fraction and iron deficiency, intravenous ferric derisomaltose administration was associated with a lower risk of hospital admissions for heart failure and cardiovascular death, further supporting the benefit of iron repletion in this population. FUNDING: British Heart Foundation and Pharmacosmos.

The Role of Iron in Calciphylaxis-A Current Review.

Calcific uraemic arteriolopathy (CUA), also known as calciphylaxis, is a rare and often fatal condition, frequently diagnosed in end-stage renal disease (ESRD) patients. Although exact pathogenesis remains unclear, iron supplementation is suggested as a potential risk factor. Iron and erythropoietin are the main stay of treatment for anaemia in ESRD patients. Few observational studies support the role of iron in the pathogenesis of calciphylaxis although data from the pivotal trial was not strongly supportive of this argument, i.e., no difference in incidence of calciphylaxis between the low-dose and high-dose iron treatment arms. Elevated levels of vascular cell adhesion molecules in association with iron excess were postulated to the pathogenesis of CUA by causing inflammation and calcification within the microvasculature. In-addition, oxidative stress generated because of iron deposition in cases of systemic inflammation, such as those seen in ESRD, may play a role in vascular calcification. Despite these arguments, a direct correlation between cumulative iron exposure with CUA incidence is not clearly demonstrated in the literature. Consequently, we do not have evidence to recommend iron reduction or cessation in ESRD patients that develop CUA.

An Analysis of Vascular Access Thrombosis Events From the Proactive IV irOn Therapy in hemodiALysis Patients Trial.

Introduction: Treatment of anemia in dialysis patients has been associated with increased risk of vascular access thrombosis (VAT). Proactive IV irOn Therapy in hemodiALysis Patients (PIVOTAL) was a clinical trial of proactive compared with reactive i.v. iron therapy in patients requiring hemodialysis. We analyzed the trial data to determine whether randomized treatment arm, alongside other clinical and laboratory variables, independently associated with VAT. Methods: In PIVOTAL, 2141 adult patients were randomized. The type of vascular access (arteriovenous fistula [AVF], arteriovenous graft [AVG], or central venous catheter [CVC]) was recorded at baseline and every month after randomization. The associations between clinical and laboratory data and first VAT were evaluated in a multivariate analysis. Results: A total of 480 (22.4%) participants experienced VAT in a median of 2.1 years of follow-up. In multivariable analyses, treatment arm (proactive vs. reactive) was not an independent predictor of VAT (hazard ratio [HR] 1.13, P = 0.18). Diabetic kidney disease (HR 1.45, P < 0.001), AVG use (HR 2.29, P < 0.001), digoxin use (HR 2.48, P < 0.001), diuretic use (HR 1.25, P = 0.02), female sex (HR 1.33, P = 0.002), and previous/current smoker (HR 1.47, P = 0.004) were independently associated with a higher risk of VAT. Angiotensin receptor blocker (ARB) use (HR 0.66, P = 0.01) was independently associated with a lower risk of VAT. Conclusion: In PIVOTAL, VAT occurred in nearly 1 quarter of participants in a median of just >2 years. In this post hoc analysis, randomization to proactive i.v. iron treatment arms did not increase the risk of VAT.

Rationale and design of a randomised trial of intravenous iron in patients with heart failure.

OBJECTIVES: For patients with a reduced left ventricular ejection fraction (LVEF) heart failure with reduced ejection fraction (HFrEF) and iron deficiency, administration of intravenous iron improves symptoms, exercise capacity and may in the following 12 months, reduce hospitalisations for heart failure. The Effectiveness of Intravenous iron treatment versus standard care in patients with heart failure and iron deficiency (IRONMAN) trial evaluated whether the benefits of intravenous iron persist in the longer term and impact on morbidity and mortality. METHODS: IRONMAN is a prospective, randomised, open-label, blinded endpoint (PROBE) event-driven trial. Patients aged ≥18 years with HFrEF (LVEF ≤45%) and evidence of iron deficiency (ferritin <100 µg/L and/or TSAT <20%) were enrolled if they had either a current or recent hospitalisation for heart failure or elevated plasma concentrations of a natriuretic peptide. Participants were randomised to receive, or not to receive, intravenous ferric derisomaltose in addition to guideline-recommended therapy for HFrEF. Every 4 months, intravenous iron was administered if either ferritin was <100 µg/L or, provided ferritin was ≤400 µg/L, TSAT was <25%. The primary endpoint is a composite of total hospitalisations for heart failure and cardiovascular death. Hospitalisation and deaths due to infection are safety endpoints. RESULTS: Trial recruitment was completed across 70 UK hospital sites in October 2021. Participants were followed until the end of March 2022. We plan to report the results by November 2022. CONCLUSIONS: IRONMAN will determine whether repeated doses of intravenous ferric derisomaltose are beneficial and safe for the long-term treatment of a broad range of patients with HFrEF and iron deficiency. TRIAL REGISTRATION NUMBER: NCT02642562.

The effect of intravenous iron supplementation on exercise capacity in iron-deficient but not anaemic patients with chronic kidney disease: study design and baseline data for a multicentre prospective double-blind randomised controlled trial.

BACKGROUND: Many people living with chronic kidney disease (CKD) are iron deficient, even though they may not be anaemic. The Iron and Muscle study aims to evaluate whether iron supplementation reduces symptoms of fatigue, improves muscle metabolism, and leads to enhanced exercise capacity and physical function. We report here the trial design and baseline characteristics. METHODS: This is a prospective, double-blind multicentre randomised controlled trial (RCT) including 75 non-dialysis stage 3-4 CKD patients with iron deficiency but without anaemia. Patients were randomly (1:1) assigned to either: i) intravenous iron therapy, or ii) placebo, with concurrent recruitment of eight CKD non-iron deficient participants and six healthy volunteers. The primary outcome of the study is the six-minute walk test (6MWT) distance between baseline and four-weeks. An additional exercise training programme for patients in both groups was initiated and completed between 4 and 12 weeks, to determine the effect of iron repletion compared to placebo treatment in the context of patients undertaking an exercise programme. Additional secondary outcomes include fatigue, physical function, muscle strength, muscle metabolism, quality of life, resting blood pressure, clinical chemistry, safety and harms associated with the iron therapy intervention and the exercise training intervention, and hospitalisations. All outcomes were conducted at baseline, 4, and 12 weeks, with a nested qualitative study, to investigate the experience of living with iron deficiency and intervention acceptability. The cohort have been recruited and baseline assessments undertaken. RESULTS: Seventy-five individuals were recruited. 44% of the randomised cohort were male, the mean (SD) age was 58 (14) years, and 56% were White. Body mass index was 31 (7) kg/m2; serum ferritin was 59 (45) µg/L, transferrin saturation was 22 (10) %, and haemoglobin was 125 (12) g/L at randomisation for the whole group. Estimated glomerular filtration rate was 35 (12) mL/min/1.73 m2 and the baseline 6MWT distance was 429 (174) m. CONCLUSION: The results from this study will address a substantial knowledge gap in the effects of intravenous iron therapy, and offer potential clinical treatment options, to improve exercise capacity, physical function, fatigue, and muscle metabolism, for non-dialysis patients with CKD who are iron-deficient but not anaemic. It will also offer insight into the potential novel effects of an 8-week exercise training programme. TRIAL REGISTRATION: EudraCT: 2018-000,144-25 Registered 28/01/2019.

Impact of ischaemic aetiology on the efficacy of intravenous ferric carboxymaltose in patients with iron deficiency and acute heart failure: insights from the AFFIRM-AHF trial.

AIMS: In AFFIRM-AHF, intravenous ferric carboxymaltose (FCM) reduced heart failure (HF) hospitalisations and improved quality of life versus placebo in iron-deficient patients stabilised after an acute HF episode. This analysis explored the effects of FCM versus placebo in patients with ischaemic and non-ischaemic HF aetiology. METHODS AND RESULTS: We included 1082 patients from AFFIRM-AHF: 590 with ischaemic HF (defined as investigator-reported ischaemic HF aetiology and/or prior acute myocardial infarction and/or prior coronary revascularisation) and 492 with non-ischaemic HF. The prevalences of male sex, comorbidities, and history of HF were higher in the ischaemic versus non-ischaemic HF subgroup. Annualised event rates for the primary composite outcome of total HF hospitalisations and cardiovascular death with FCM versus placebo were 65.3 versus 100.6 per 100 patient-years in the ischaemic HF subgroup (rate ratio [RR] 0.65, 95% confidence interval [CI] 0.47-0.89, p = 0.007) and 58.3 versus 52.5 in the non-ischaemic HF subgroup (RR 1.11, 95% CI 0.75-1.66, p = 0.60) (pinteraction  = 0.039). An interaction between HF aetiology and treatment effect was also observed for the secondary outcome of total HF hospitalisations (pinteraction  = 0.038). A nominal increase in quality of life, assessed using the 12-item Kansas City Cardiomyopathy Questionnaire, was observed with FCM versus placebo, within each subgroup. CONCLUSIONS: Heart failure hospitalisations and cardiovascular deaths occurred at a higher rate in patients with ishaemic versus those with non-ischaemic HF and were reduced by FCM versus placebo only in ischaemic patients. Further studies are needed to assess the role of aetiology in FCM efficacy.

Hypoxia-inducible factor prolyl hydroxylase enzyme inhibitors: ready for primetime?

PURPOSE OF REVIEW: Hypoxia-inducible factor (HIF) prolyl hydroxylase inhibitors have recently been developed as a new treatment for anemia associated with chronic kidney disease (CKD). Several of these have been approved in Europe (roxadustat), China, and Japan, but none approved in the United States to date, although daprodustat has been submitted as a new drug application to the Food and Drug Administration. The aim of this review is to critically appraise the available data, particularly the most recent publications, and offer a personal viewpoint on whether or not these drugs are ready for primetime. RECENT FINDINGS: The efficacy of HIF prolyl hydroxylase inhibitors in improving CKD anemia and maintaining a higher hemoglobin is undisputed, but there remain some concerns about safety, particularly in the long term. Some of the safety concerns may result from an exaggerated pharmacological response, while other potential adverse effects could be due to transcriptional effects of these agents beyond genes involved in erythropoiesis. SUMMARY: HIF prolyl hydroxylase inhibitors are already being used in clinical practice in several countries of the world, and ongoing research is being conducted to define the role of these drugs not only in the management of anemia but also beyond into other clinical settings.

Efficacy and Safety of Daprodustat for Treatment of Anemia of Chronic Kidney Disease in Incident Dialysis Patients: A Randomized Clinical Trial.

Importance: Daprodustat, a hypoxia-inducible factor prolyl hydroxylase inhibitor, is being evaluated as an oral alternative to conventional erythropoiesis-stimulating agent (ESA) therapy. Few studies of anemia treatment in an incident dialysis (ID) population have been reported. Objective: To evaluate the efficacy and safety of daprodustat vs darbepoetin alfa in treating anemia of chronic kidney disease in ID patients. Design, Setting, and Participants: This prospective, randomized, open-label clinical trial was conducted from May 11, 2017, through September 24, 2020, in 90 centers across 14 countries. Patients with advanced CKD were eligible if they planned to start dialysis within 6 weeks from screening or had started and received hemodialysis (HD) or peritoneal dialysis (PD) within 90 days before randomization, had a screening hemoglobin (Hb) concentration of 8.0 to 10.5 g/dL (to convert to grams per liter, multiply by 10) and a randomization Hb of 8.0 to 11.0 g/dL, were ESA-naive or had received limited ESA treatment, and were iron-replete. Interventions: Randomized 1:1 to daprodustat or darbepoetin alfa. Main Outcomes and Measures: The primary analysis in the intent-to-treat population evaluated the mean change in Hb concentration from baseline to evaluation period (weeks 28-52) to assess noninferiority of daprodustat vs darbepoetin alfa (noninferiority margin, -0.75 g/dL). The mean monthly intravenous (IV) iron dose from baseline to week 52 was the principal secondary end point. Rates of treatment-emergent and serious adverse events (AEs) were also compared between treatment groups to assess safety and tolerability. Results: A total of 312 patients (median [IQR] age, 55 [45-65] years; 194 [62%] male) were randomized to either daprodustat (157 patients; median [IQR] age, 52.0 [45-63] years; 96 [61%] male) or darbepoetin alfa (155 patients; median [IQR] age, 56.0 [45-67] years; 98 [63%] male); 306 patients (98%) completed the trial. The mean (SD) Hb concentration during the evaluation period was 10.5 (1.0) g/dL for the daprodustat and 10.6 (0.9) g/dL for the darbepoetin alfa group, with an adjusted mean treatment difference of -0.10 g/dL (95% CI, -0.34 to 0.14 g/dL), indicating noninferiority. There was a reduction in mean monthly IV iron use from baseline to week 52 in both treatment groups; however, daprodustat was not superior compared with darbepoetin alfa in reducing monthly IV iron use (adjusted mean treatment difference, 19.4 mg [95% CI, -11.0 to 49.9 mg]). Adverse event rates were 76% for daprodustat vs 72% for darbepoetin alfa. Conclusions and Relevance: This randomized clinical trial found that daprodustat was noninferior to darbepoetin alfa in treating anemia of CKD and may represent a potential oral alternative to a conventional ESA in the ID population. Trial Registration: ClinicalTrials.gov Identifier: NCT03029208.

Analysis of oxidative stress, inflammation and endothelial function following intravenous iron in chronic kidney disease in the Iron and Heart Trial.

Iron deficiency commonly affects patients with chronic kidney disease and has an important burden in disease trajectory and quality of life; nonetheless current guidelines do not advocate treatment of iron-deficiency without anemia in this patient group. Concerns exist regarding the potential effects of intravenous iron on oxidative stress, inflammation, and endothelial function. As part of a multicenter double-blinded randomized controlled clinical trial, we examined the effects of a single dose of intravenous iron vs. placebo on biomarkers of oxidative stress, inflammation and endothelial function in non-anemic iron deficient patients (serum ferritin < 100 µg/L and/or transferrin saturation < 20%) with chronic kidney disease (stage 3b-5). Fifty-four individuals were randomized to receive ferric derisomaltose (n = 26) or placebo (n = 28). Ferric derisomaltose was associated with a non-significant decrease in mean F2-isoprostane and no effect on thiobarbituric acid reactive substances when compared to placebo throughout follow up. No effect on inflammatory markers was observed. A modest but statistically significant rise in E-selectin was noted in the intravenous iron group at 1 month and 3 month follow-up (p = 0.030 and p = 0.002 respectively). These results suggest ferric derisomaltose administration in non-dialysis dependent chronic kidney disease patients who are iron deficient does not induce prolonged oxidative stress or inflammation. Larger trials are required to quantify the benefit of intravenous iron administration in this patient group.