Phase 3 Study of Roxadustat to Treat Anemia in Non-Dialysis-Dependant CKD

Cardiovascular and renal safety outcomes of hypoxia-inducible factor prolyl-hydroxylase inhibitor roxadustat for anemia patients with chronic kidney disease: a systematic review and meta-analysis

This systematic review and meta-analysis were conducted to evaluate the cardiac and kidney-related adverse effects of roxadustat for the treatment of anemia in CKD patients. 18 trials with a total of 8806 participants were identified for analysis. We employed a fixed-effects model for analysis. The pooled result revealed no significant difference in the risk of occurrence of cardiac disorders when comparing CKD patients receiving roxadustat with the placebo (RR = 1.049; CI [0.918 to 1.200]) or ESA (RR = 1.066; CI [0.919 to 1.235]), in both dialysis-dependent (DD) (RR = 1.094; CI [0.925 to 1.293]) or non-dialysis-dependent (NDD) (RR = 1.036; CI [0.916 to 1.171]) CKD patients. No significant difference was observed in the risk of kidney-related adverse events when comparing roxadustat with the placebo (RR = 1.088; CI [0.980 to 1.209]) or ESA (RR = 0.968; CI [0.831 to 1.152]), in DD (RR = 2.649; CI [0.201 to 34.981]) or NDD (RR = 1.053; CI [0.965 to 1.149]) CKD patients. A high risk of hyperkalemia was observed in the roxadustat group in DD (RR = 0.939; CI [0.898 to 0.981]). Incidence of hypertension was higher in the roxadustat for NDD patients (RR = 1.198; CI [1.042 to 1.377]), or compared to the placebo (RR = 1.374; CI [1.153 to 1.638]). In summary, the risk of cardiac or kidney-related events observed in the roxadustat was not significantly increase whether in DD or NDD patients. However, attention must be paid to the occurrence of hyperkalemia for DD patients and hypertension in NDD patients using roxadustat.

The Efficacy and Safety of Roxadustat for the Treatment of Posttransplantation Anemia: A Randomized Study

Introduction

Roxadustat, an oral hypoxia-inducible factor prolyl hydroxylase (HIF-PH) inhibitor, can stimulate erythropoiesis. Our objective was to evaluate the efficacy and safety of roxadustat for the treatment of posttransplantation anemia (PTA).

Methods

A total of 150 adult renal transplant recipients who underwent PTA were randomized to either the experimental group or the control group. During the 12-week randomized phase, the experimental group was randomized to oral iron and roxadustat treatment, and the control group was randomized to oral iron treatment only. The randomized phase was followed by a 12-week extended treatment period in which all participants were prescribed roxadustat treatment according to hemoglobin (Hb) levels. All the participants were followed-up with every 4 weeks. The primary end points were the change in Hb levels and response rate throughout the randomized period.

Results

A total of 128 participants completed the randomized treatment period (90 in the experimental group and 38 in the control group). The mean Hb concentration at week 12 was 12.20 g/dl in the experimental group and 11.19 g/dl in the control group. A significantly higher proportion of participants who achieved Hb responses were in the experimental group than in the control group. Differences in serum iron, total iron-binding capacity (TIBC) and transferrin from baseline to week 8 to 12 were significant between the 2 groups. The adverse event profiles were comparable between the 2 groups.

Conclusion

Roxadustat increased Hb in adult renal transplant recipients who underwent PTA, with an adverse event profile comparable to that of the control group.

A novel scenario in the therapeutic management of anemia of chronic kidney disease: placement and use of roxadustat

Anemia is a frequent and early chronic kidney disease (CKD) complication. Its management is currently based on oral or intravenous iron supplements, erythropoiesis-stimulating agents, and red blood cell transfusions, when the benefits of transfusion outweigh the risks. Anemia in CKD patients is underdiagnosed and undertreated. Current standard of care is associated with challenges and therefore new treatment approaches have been sought. Hypoxia-inducible factor-prolyl-hydroxylase enzyme inhibitors are a new class of orally administered drugs used to treat anemia associated with CKD. Small-molecule hypoxia-inducible factor-prolyl-hydroxylase inhibitors have a novel mechanism of action that activates the hypoxia-inducible factor (oxygen-sensing) pathway resulting in a coordinated erythropoietic response, leading to increased endogenous erythropoietin production, improved iron absorption and transport, and reduced hepcidin. Roxadustat is the first hypoxia-inducible factor-prolyl-hydroxylase inhibitor approved by the European Medicines Agency (EMA) and reimbursed in Italy by the Italian Medicines Agency (AIFA) for the treatment of adult patients with symptomatic CKD-related anemia. This authorization was based on the outcome of a globally-conducted phase 3 clinical trial program comprising eight pivotal multicenter randomized studies. In the absence of up-to-date guidelines, we performed a critical appraisal of the placement and use of roxadustat in this therapeutic context.

Consensus commentary and position of the Italian Society of Nephrology on KDIGO controversies conference on novel anemia therapies in chronic kidney disease

Hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHIs) are new drugs developed for the treatment of anemia associated with chronic kidney disease (CKD). This class of drugs stimulates endogenous erythropoietin production and, at the same time, improves iron absorption and mobilization of iron stores (less evident with daprodustat, vadadustat and enarodustat). Several studies have been published in the last few years showing that these agents are not inferior to standard therapy in correcting anemia associated with CKD. The efficacy of HIF-PHIs is coupled with a safety profile comparable to that of standard erythropoiesis stimulating agent (ESA) treatment. However, studies with HIF-PHIs were not long enough to definitively exclude the impact of new drugs on adverse events, such as cancer, death and possibly cardiovascular events, that usually occur after a long follow-up period. Kidney Disease: Improving Global Outcomes (KDIGO) recently reported the conclusions of the Controversies Conference on HIF-PHIs held in 2021. The goal of the present position paper endorsed by the Italian Society of Nephrology is to better adapt the conclusions of the latest KDIGO Conference on HIF-PHIs to the Italian context by reviewing the efficacy and safety of HIF-PHIs as well as their use in subpopulations of interest as emerged from more recent publications not discussed during the KDIGO Conference.

Identification of 3-aryl-5-methyl-isoxazole-4-carboxamide derivatives and analogs as novel HIF-2α agonists through docking-based virtual screening and structural modification

Hypoxia-inducible factor-2 (HIF-2) serves as the pivotal transcription factor in cellular responses to low oxygen levels, particularly concerning the regulation of erythropoietin (EPO) production. A docking-based virtual screening on crystal structures of HIF-2α inhibitors unexpectedly identified 3-phenyl-5-methyl-isoxazole-4-carboxamide derivative v19 as a hit of HIF-2α agonist. Further structural optimizations of compound v19 led to the discovery of a series of HIF-2α agonists with novel scaffolds. The most promising compounds 12g and 14d exhibited potent HIF-2α agonistic activities in vitro with EC50 values of 2.29 μM and 1.78 μM, respectively. Molecular dynamics simulations have revealed their capacity to allosterically enhance HIF-2 dimerization, which shed light on their mechanism of action. Moreover, compound 14d demonstrated a favorable pharmacokinetic (PK) profile, boasting an impressive oral bioavailability value of 68.71 %. These findings strongly suggest that compound 14d is an auspicious lead compound for the treatment of renal anemia.

Impact of C-reactive protein on the effect of Roxadustat for the treatment of anemia in chronic kidney disease: a systematic review of randomized controlled trials

BACKGROUND

Chronic inflammation, reflected by an increased blood C-reactive protein (CRP) level, is common in patients with chronic kidney disease (CKD) and is involved in the development of renal anemia. This systematic review aims to investigate the impacts of CRP on the efficacy of hypoxia-inducible factor-prolyl hydroxylase inhibitors (HIF-PHIs) in the treatment of renal anemia in patients with CKD.

METHODS

We conducted a comprehensive search of electronic databases including Pubmed, Web of Science, Embase, Cochrane Library, CNKI, Wanfang, and the International Clinical Trials Registry Platform (ICTRP), from their inception to May 19, 2022. We systematically reviewed evidence from randomized controlled trials using HIF-PHIs for renal anemia treatment. The mean difference (MD) in changes in hemoglobin concentration (∆Hb) before and after treatment served as the meta-analysis outcome, utilizing a random-effects model. We compared groups with CRP levels greater than or equal to the upper limit of normal (ULN) and less than the ULN. Additionally, further analysis was conducted in the CRP ≥ ULN group comparing HIF-PHIs and erythropoiesis-stimulating agents (ESA).

RESULTS

A total of 7 studies from 6 publications were included in the analysis. In the comparison between the CRP ≥ ULN group and the CRP < ULN group, 524 patients from 4 studies were incorporated into the analysis. All patients received roxadustat as the primary intervention. The pooled results revealed no significant difference in ΔHb between patients with CRP ≥ ULN and CRP < ULN at baseline (Mean Difference: 0.00, 95% Confidence Interval: -0.32 to 0.33, P = 0.99). Moreover, within the CRP ≥ ULN group, three studies involving 1399 patients compared the efficacy of roxadustat and erythropoiesis-stimulating agents (ESAs). The results indicated no significant difference in ΔHb between patients treated with ESAs and HIF-PHIs (Mean Difference: 0.24, 95% Confidence Interval: -0.08 to 0.56, P = 0.14). In terms of medication dosage, an increase in ESA dose over time was observed across various studies, particularly evident in the CRP ≥ ULN group, while the dose of roxadustat remains constant over time and is not influenced by the baseline levels of CRP.

CONCLUSIONS

Our systematic review demonstrates that roxadustat exhibits similar efficacy across different CRP levels. Moreover, within the CRP ≥ ULN group, roxadustat can maintain efficacy comparable to ESA without the necessity for dose escalation.

TRIAL REGISTRATION

CRD42023396704.

Efficacy and safety of hypoxia-inducible factor prolyl hydroxylase inhibitors in patients with chronic kidney disease: meta-analysis of phase 3 randomized controlled trials

Background

Hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHIs) are new therapeutic agents for anaemia in chronic kidney disease (CKD). We evaluated by meta-analysis and meta-regression the efficacy and safety of HIF-PHIs in patients with CKD-related anaemia.

Methods

We selected phase 3 randomized clinical trials (RCTs) comparing HIF-PHIs and erythropoiesis-stimulating agents (ESAs) in dialysis and non-dialysis patients. Efficacy outcomes were the changes from baseline of haemoglobin, iron parameters (hepcidin, serum iron, TIBC, TSAT, ferritin) and intravenous iron dose; as safety outcomes we considered cancer, adjudicated major adverse cardiovascular events (MACE), MACE+ (MACE plus hospitalization for hearth failure or unstable angina or thromboembolic event), thrombotic events (deep vein thrombosis, pulmonary embolism), arterovenous fistula (AVF) thrombosis and death.

Results

We included 26 RCTs with 24 387 patients. Random effect meta-analysis of the unstandardized mean difference between HIF-PHIs and ESAs showed a significant change in haemoglobin levels from baseline of 0.10 g/dL (95% CI 0.02 to 0.17). Meta-regression analysis showed a significantly higher haemoglobin change for HIF-PHIs in younger patients and versus short-acting ESA (0.21 g/dL, 95% CI 0.12 to 0.29 versus -0.01, 95% CI -0.09 to 0.07 in studies using long-acting ESA, P < .001). No significant effect on heterogeneity was found for type of HIF-PHIs. In comparison with ESAs, HIF-PHIs induced a significant decline in hepcidin and ferritin and a significant increase in serum iron and TIBC, while TSAT did not change; intravenous iron dose was lower with HIF-PHI (-3.1 mg/week, 95% CI -5.6 to -0.6, P = .020). Rate ratio of cancer (0.93, 95% CI 0.76 to 1.13), MACE (1.00, 95% CI 0.94 to 1.07), MACE+ (1.01, 95% CI 0.95 to 1.06), thrombotic events (1.08, 95% CI 0.84 to 1.38), AVF thrombosis (1.02, 95% CI 0.93 to 1.13) and death (1.02, 95% CI 0.95 to 1.13) did not differ between HIF-PHIs and ESAs.

Conclusions

HIF-PHIs at the doses selected for the comparisons are effective in correcting anaemia in comparison with ESA therapy with a significant impact on iron metabolism without notable difference among various agents. No safety signals emerge with use of HIF-PHIs.

Novel anemia therapies in chronic kidney disease: conclusions from a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference

Anemia is common in patients with chronic kidney disease and is associated with a high burden of morbidity and adverse clinical outcomes. In 2012, Kidney Disease: Improving Global Outcomes (KDIGO) published a guideline for the diagnosis and management of anemia in chronic kidney disease. Since then, new data from studies assessing established and emerging therapies for the treatment of anemia and iron deficiency have become available. Beginning in 2019, KDIGO planned 2 Controversies Conferences to review the new evidence and its potential impact on the management of anemia in clinical practice. Here, we report on the second of these conferences held virtually in December 2021, which focused on a new class of agents-the hypoxia-inducible factor-prolyl hydroxylase inhibitors (HIF-PHIs). This report provides a review of the consensus points and controversies from this second conference and highlights areas that warrant prioritization for future research.

An updated meta-analysis on the efficacy and safety of hypoxia-inducible factor prolyl hydroxylase inhibitor treatment of anemia in nondialysis-dependent chronic kidney disease

BACKGROUND

Renal anemia, a common complication and threat factor of chronic kidney disease (CKD), has long been treated with injectable erythropoietin-stimulating agents (ESAs). As concerns regarding cardiovascular safety and erythropoietin resistance to ESAs have emerged, alternative therapies are urgently needed. Hypoxia-inducible factor prolyl hydroxylase inhibitor (HIF-PHI), an oral agent, has been proven to be effective in improving renal anemia. However, the effects of HIF-PHIs on nondialysis-dependent CKD (NDD-CKD) have yet to be supported by updated meta-analyses.

METHODS

A meta-analysis of clinical randomized controlled trials (RCTs) on HIF-PHI treatment of NDD-CKD patients based on PubMed, EMBASE, and Cochrane databases as of July 16th, 2023, was conducted. The primary outcomes were the level of hemoglobin (Hb) postintervention and the ratio of Hb responses. Most of the analysis was conducted via RevMan 5.3 software using a random-effects model. Stata (version 15.0) was used to analyze the publication bias.

RESULTS

Twenty-two studies with a total of 7178 subjects in the HIF-PHI group, 3501 subjects in the ESA group and 2533 subjects in the placebo group were enrolled. HIF-PHIs increased the level of Hb and improved iron metabolism but were not inferior to ESAs in terms of safety.

CONCLUSIONS

HIF-PHIs may be a convenient and safe alternative to ESAs in patients with NDD-CKD and anemia.

Iron Parameters in Patients Treated with Roxadustat for Anemia of Chronic Kidney Disease

Roxadustat is a novel agent with a distinct mechanism of action compared to erythropoiesis-stimulating agents (ESAs) and a potentially different combination of effects on iron parameters. This narrative review describes the effects of roxadustat on iron parameters and on hemoglobin levels in the context of iron supplementation in patients with anemia of non-dialysis-dependent (NDD) or dialysis-dependent (DD) chronic kidney disease (CKD). Roxadustat use was associated with a greater reduction in serum ferritin levels than seen with ESAs and an increase in serum iron levels compared to a decrease with ESAs. Decreases in transferrin saturation in patients treated with roxadustat were relatively small and, in the case of patients with NDD CKD, not observed by Week 52. These changes reflect the concomitant increases in both serum iron and total iron-binding capacity. Compared to placebo and an ESA, roxadustat improved iron availability and increased erythropoiesis while requiring less intravenous iron use. Hepcidin levels generally decreased in patients who received roxadustat compared to baseline values in all CKD populations; these decreases appear to be more robust with roxadustat than with an ESA or placebo. The mechanisms behind the effects of roxadustat and ESAs on iron availability and stores and erythropoiesis appear to differ and should be considered holistically when treating anemia of CKD.

Hypoxia-inducible factors and essential hypertension: narrative review of experimental and clinical data

Hypoxia-inducible factor (HIFs) is a new class of drug developed for the management of anemia in chronic kidney disease (CKD) patients. HIFs increase the production of erythropoietin in the kidney and liver, enhance the absorption and utilization of iron, and stimulate the maturation and proliferation of erythroid progenitor cells. Besides, HIFs regulate many physiologic processes by orchestrating the transcription of hundreds of genes. Essential hypertension (HT) is an epidemic worldwide. HIFs play a role in many biological processes involved in the regulation of blood pressure (BP). In the current review, we summarize pre-clinical and clinical studies investigating the relationship between HIFs and BP regulation in patients with CKD, conflicting issues, and discuss future potential strategies.

Efficacy and Safety of Hypoxia-Inducible Factor Prolyl Hydroxylase Inhibitor Therapy for Anemia in Renal Transplantation Patients by Prior Erythropoiesis Stimulating Agent Use

BACKGROUND

The present study aimed to clarify the efficacy and safety of hypoxia-inducible factor prolyl hydroxylase inhibitor (HIF-PHI) therapy for anemia in renal transplant (RTx) patients.

METHODS

After successful RTx, 26 patients requiring treatment for anemia were divided into 2 groups (erythropoiesis-stimulating agent [ESA] group and non-ESA group) based on whether an ESA was used before starting HIF-PHI therapy. The chronological changes in hemoglobin (Hb) values during the 6 months after the start of HIF-PHI therapy were investigated in each group, and the incidence of adverse events was compared.

RESULTS

There were 18 patients in the ESA group and 8 patients in the non-ESA group. The median (IQR) Hb values in the 2 groups were 11.35 (10.4-12.3) and 10.15 (8.9-10.4) g/dL, respectively. The chronological changes in the median (IQR) Hb values pre-HIF-PHI and 1, 3, and 6 months after starting HIF-PHI were 11.4 (10.4-12.4), 12.0 (10.7-12.4), 11.9 (10.9-13.4), and 11.5 (10.6-12.7) g/dL, respectively, in the ESA group, and 10.2 (8.7-10.4), 11.0 (10.4-11.7), 12.2 (11.6-13.2), and 12.5 (11.3-12.7) g/dL, respectively, in the non-ESA group. In the ESA group, Hb values were not significantly decreased after HIF-PHI administration (P = .14); in the non-ESA group, Hb values improved significantly (P = .002). Two patients developed diarrhea in the ESA group, and one patient developed appetite loss in the non-ESA group.

CONCLUSIONS

Hypoxia-inducible factor prolyl hydroxylase inhibitor was effective and safe for RTx patients regardless of prior ESA use.

Cardiac and Kidney Adverse Effects of HIF Prolyl-Hydroxylase Inhibitors for Anemia in Patients With CKD Not Receiving Dialysis: A Systematic Review and Meta-analysis

RATIONALE & OBJECTIVE

Hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHIs) are novel, orally administered agents for anemia management in chronic kidney disease (CKD). We evaluated the cardiac and kidney-related adverse effects of HIF-PHIs among patients with CKD and anemia.

STUDY DESIGN

Systematic review and meta-analysis of randomized controlled trials (RCTs).

SETTING & STUDY POPULATIONS

Patients with anemia and CKD not receiving maintenance dialysis.

SELECTION CRITERIA FOR STUDIES

RCTs comparing HIF-PHIs to placebo or an erythropoiesis-stimulating agent (ESA) with primary outcomes of cardiac and kidney-related adverse events (AEs).

DATA EXTRACTION

Two independent reviewers evaluated RCTs for eligibility and extracted relevant data.

ANALYTICAL APPROACH

Dichotomous variables were pooled using the Mantel-Haenszel method and presented as risk ratios (RRs). Subgroup analyses evaluated different intervention times and HIF-PHIs, as well as phase 2 versus phase 3 trials. The certainty of findings was rated according to GRADE criteria.

RESULTS

Twenty-three studies with 15,144 participants were included. No significant difference in the risk of cardiac AEs was observed between the HIF-PHIs group and the placebo (RR, 1.02 [95% CI, 0.89-1.16]; moderate certainty) or ESA (RR, 1.06 [95% CI, 0.98-1.14]; low certainty) groups. No significant difference in the risk of kidney-related AEs was observed between the HIF-PHIs group and the placebo (RR, 1.09 [95% CI, 0.98-1.20]; moderate certainty) or ESA (RR, 1.00 [95% CI, 0.94-1.06]; low certainty) groups. The occurrence of hypertension and hyperkalemia was higher in the HIF-PHIs group than in the placebo group (RRs of 1.35 [95% CI, 1.14-1.60] and 1.25 [95% CI, 1.03-1.51], respectively; both findings had high certainty). The occurrence of hypertension was lower in the HIF-PHIs group than in the ESA group (RR, 0.89 [95% CI, 0.81-0.98]; moderate certainty).

LIMITATIONS

The reporting criteria of cardiac and kidney-related AEs and dosage of HIF-PHIs were inconsistent across trials.

CONCLUSIONS

The occurrence of cardiac or kidney-related AEs in the HIF-PHI groups were not different compared with placebo or ESA groups.

REGISTRATION

Registered at PROSPERO with registration number CRD42021228243.

Safety of Roxadustat Versus Erythropoiesis-Stimulating Agents in Patients with Anemia of Non-dialysis-Dependent or Incident-to-Dialysis Chronic Kidney Disease: Pooled Analysis of Four Phase 3 Studies

INTRODUCTION

This study was conducted to elucidate the safety of roxadustat, an oral medication, in patients with non-dialysis-dependent (NDD) or incident dialysis dialysis-dependent (ID-DD) chronic kidney disease (CKD).

METHODS

Safety results from four phase 3, randomized, open-label studies comparing roxadustat to an erythropoiesis-stimulating agent (ESA) in men and women with NDD or ID-DD CKD with anemia were pooled and evaluated. Endpoints were time to major adverse cardiovascular event (MACE; myocardial infarction, stroke, and all-cause mortality) and MACE+ (MACE plus congestive heart failure or unstable angina requiring hospitalization), all-cause mortality, and treatment-emergent adverse events (TEAEs). MACE and MACE+ were evaluated for non-inferiority at 1.8- and 1.3-margins using hazard ratios (HRs) and 95% confidence intervals (CIs). TEAEs were descriptively summarized.

RESULTS

In total, 2142 patients were evaluated (1083 roxadustat; 1059 ESA). Roxadustat was comparable to ESA for risk of MACE (HR 0.79, 95% CI 0.61-1.02), MACE+ (HR 0.78, 95% CI 0.62-0.98), and all-cause mortality (HR 0.78, 95% CI 0.57-1.05). TEAEs were comparable between roxadustat and ESA groups, including any TEAE [incidence rate per 100 (IR/100) patient-exposure years 56.1 vs. 53.5], TEAEs leading to study drug discontinuation (IR/100 patient-exposure years 6.7 vs. 5.1), and TEAEs leading to death (IR/100 patient-exposure years 6.9 vs. 7.4).

CONCLUSION

There was no evidence of increased risk of cardiovascular events or mortality with roxadustat compared with ESA in patients with anemia who have NDD or ID-DD CKD. Although TEAEs occurred commonly in both the roxadustat and ESA groups, patients infrequently discontinued the study drug because of an adverse event.

CLINICAL TRIAL REGISTRATION NUMBERS

DOLOMITES, 1517-CL-0610 [NCT02021318]; HIMALAYAS, FGCL-4592-063 [NCT02052310]; SIERRAS, FGCL-4592-064 [NCT02273726]; and ROCKIES, D5740C00002 [NCT02174731].

Lower starting dose of roxadustat in non-dialysis-dependent chronic kidney disease patients with anaemia: a study protocol for a randomised, multicentre, open-label study

INTRODUCTION

Roxadustat is a first-in-class oral therapy that treats chronic kidney disease (CKD) anaemia with the benefit of a novel mechanism of action that consistently corrects and maintains haemoglobin (Hb) across the spectrum of non-dialysis-dependent (NDD) CKD anaemia with an acceptable safety profile.

METHODS AND ANALYSIS

This is a randomised, control, open-label, multicentre trial. About 250 adult Chinese participants with stage 3-5 CKD NDD in approximately 30 centres will be enrolled, randomly assigned in a 1:1 ratio, to receive a 16-week treatment and 4-week follow-up. The interventions for study arm are <60 kg: 50 mg TIW and ≥60 kg: 70 mg TIW; for control arm, <60 kg: 70 mg TIW and ≥60 kg: 100 mg TIW. The primary endpoint is the mean change in haemoglobin level from baseline to average over weeks 12-16. Secondary endpoints are to assess the proportion of subjects achieving an average Hb level of 100 to 120 g/L over weeks 12-16, the Hb variability, the rescue therapy requirement between two groups and the safety in two groups. The exploratory objectives are expected to evaluate the rate and time of Hb response, times of dose adjustment, the proportion of subjects with rapid Hb rise, overshooting during the treatment between two different starting dose groups, and subgroup analyses.

ETHICS AND DISSEMINATION

The Medical Ethics Committee of Chinese PLA General Hospital has approved this study (No. S2020-523-05) and will be performed in accordance with the Declaration of Helsinki. Participant consent will be obtained in writing. Results will be disseminated via peer-reviewed publications and conference presentations.

TRIAL REGISTRATION NUMBER

ChiCTR2100045359.

Hypoxia-Inducible Factor Prolyl Hydroxylase Inhibitors and Iron Metabolism

The production of erythropoietin (EPO), the main regulator of erythroid differentiation, is regulated by hypoxia-inducible factor (HIF). HIF2α seems to be the principal regulator of EPO transcription, but HIF1α and 3α also may have additional influences on erythroid maturation. HIF is also involved in the regulation of iron, an essential component in erythropoiesis. Iron is essential for the organism but is also highly toxic, so its absorption and retention are strictly controlled. HIF also induces the synthesis of proteins involved in iron regulation, thereby ensuring the availability of iron necessary for hematopoiesis. Iron is a major component of hemoglobin and is also involved in erythrocyte differentiation and proliferation and in the regulation of HIF. Renal anemia is a condition in which there is a lack of stimulation of EPO synthesis due to decreased HIF expression. HIF prolyl hydroxylase inhibitors (HIF-PHIs) stabilize HIF and thereby allow it to be potent under normoxic conditions. Therefore, unlike erythropoiesis-stimulating agents, HIF-PHI may enhance iron absorption from the intestinal tract and iron supply from reticuloendothelial macrophages and hepatocytes into the plasma, thus facilitating the availability of iron for hematopoiesis. The only HIF-PHI currently on the market worldwide is roxadustat, but in Japan, five products are available. Clinical studies to date in Japan have also shown that HIF-PHIs not only promote hematopoiesis, but also decrease hepcidin, the main regulator of iron metabolism, and increase the total iron-binding capacity (TIBC), which indicates the iron transport capacity. However, concerns about the systemic effects of HIF-PHIs have not been completely dispelled, warranting further careful monitoring.

Genetically proxied therapeutic prolyl-hydroxylase inhibition and cardiovascular risk

Prolyl hydroxylase (PHD) inhibitors are in clinical development for anaemia in chronic kidney disease. Epidemiological studies have reported conflicting results regarding safety of long-term therapeutic haemoglobin (Hgb) rises through PHD inhibition on risk of cardiovascular disease. Genetic variation in genes encoding PHDs can be used as partial proxies to investigate the potential effects of long-term Hgb rises. We used Mendelian randomization to investigate the effect of long-term Hgb level rises through genetically proxied PHD inhibition on coronary artery disease (CAD: 60 801 cases; 123 504 controls), myocardial infarction (MI: 42 561 cases; 123 504 controls) or stroke (40 585 cases; 406 111 controls). To further characterize long-term effects of Hgb level rises, we performed a phenome-wide association study (PheWAS) in up to 451 099 UK Biobank individuals. Genetically proxied therapeutic PHD inhibition, equivalent to a 1.00 g/dl increase in Hgb levels, was not associated (at P < 0.05) with increased odds of CAD; odd ratio (OR) [95% confidence intervals (CI)] = 1.06 (0.84, 1.35), MI [OR (95% CI) = 1.02 (0.79, 1.33)] or stroke [OR (95% CI) = 0.91 (0.66, 1.24)]. PheWAS revealed associations with blood related phenotypes consistent with EGLN's role, relevant kidney- and liver-related biomarkers like estimated glomerular filtration rate and microalbuminuria, and non-alcoholic fatty liver disease (Bonferroni-adjusted P < 5.42E-05) but these were not clinically meaningful. These findings suggest that long-term alterations in Hgb through PHD inhibition are unlikely to substantially increase cardiovascular disease risk; using large disease genome-wide association study data, we could exclude ORs of 1.35 for cardiovascular risk with a 1.00 g/dl increase in Hgb.

Effects of roxadustat on anemia, iron metabolism, and lipid metabolism in patients with non-dialysis chronic kidney disease

Background

We determined the effects of roxadustat on the values of anemia, iron metabolism, renal function, proteinuria, and lipid metabolism and identified the associated factors of the change in hemoglobin levels after roxadustat administration in non-dialysis chronic kidney disease (CKD) patients who were receiving an erythropoietin-stimulating agent (ESA).

Methods

We conducted retrospective analysis of the changes in hemoglobin, serum ferritin, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglyceride levels; transferrin saturation; the estimated glomerular filtration rate; and the urinary protein/creatinine ratio over 24 weeks after the change from an ESA to roxadustat in 50 patients with non-dialysis CKD and anemia (roxadustat group). Seventy-two patients with non-dialysis CKD and anemia who proceeded ESA therapy were used as the control (ESA) group.

Results

We observed no significant between-group differences in clinical parameters at baseline except for the significantly lower hemoglobin concentration and lower proportion of diabetes mellitus in the roxadustat group. The hemoglobin concentration was significantly higher in the roxadustat group after 24 weeks (11.3 ± 1.2 versus 10.3 ± 1.0 g/dL; value of p < 0.05), whereas the transferrin saturation, ferritin concentration, estimated glomerular filtration rate, and urinary protein/creatinine ratio were not different between the two groups. TC (135.9 ± 40.0 versus 165.3 ± 38.4 mg/dL; value of p < 0.05), LDL-C (69.1 ± 28.3 versus 87.2 ± 31.5 mg/dL; value of p < 0.05), HDL-C (41.4 ± 13.5 versus 47.2 ± 15.3 mg/dL; value of p < 0.05), and triglyceride concentrations (101.5 ± 52.7 versus 141.6 ± 91.4 mg/dL, value of p < 0.05) were significantly lower in the roxadustat group compared with the ESA group at 24 weeks. Multiple linear regression analysis showed that the roxadustat dose at baseline (standard coefficient [β] = 0.280, value of p = 0.043) was correlated with the change in the hemoglobin levels during the first 4 weeks of roxadustat treatment, whereas age (β = 0.319, value of p = 0.017) and the roxadustat dose at 24 weeks (β = -0.347, value of p = 0.010) were correlated with the hemoglobin concentration after 24 weeks of roxadustat administration.

Conclusion

Roxadustat can improve anemia and reduce serum cholesterol and triglyceride levels in non-dialysis CKD patients after the patients' treatment was switched from an ESA without affecting renal function or proteinuria. These results indicate that roxadustat has superior effects to ESAs regarding anemia and lipid metabolism at the dose selected for the comparison in patients with non-dialysis CKD.

Updates on Hypoxia-Inducible Factor Prolyl Hydroxylase Inhibitors in the Treatment of Renal Anemia

Background

Anemia is a common complication of chronic kidney disease. The hypoxia-inducible factor prolyl hydroxylase inhibitor (HIF-PHI) is a new class of oral drugs for the treatment of renal anemia.

Summary

Clinical trials have consistently shown that HIF-PHIs can effectively increase hemoglobin in both the dialysis population and the nondialysis population. The effects of HIF-PHIs in treating renal anemia include promoting endogenous erythropoietin production and facilitating iron mobilization. Several studies suggest that the erythropoiesis effect of roxadustat is less affected by inflammation. Careful monitoring of thromboembolic events and tumor before and during HIF-PHI treatment is necessary.

Key Messages

HIF-PHIs are effective in correcting renal anemia. The long-term safety of HIF-PHIs needs to be further studied.

Innovations thérapeutiques dans la prise en charge de l’anémie de la maladie rénale chronique Therapeutic innovations in the management of chronic kidney disease-associated anemia

Anemia is a common complication of chronic kidney disease (CKD). The insufficient erythropoietin (EPO) production by the kidneys and iron deficiency are the main causes. Iron supplementation and the administration of recombinant EPO are the main treatment modalities. New iron formulations that can be administered orally, intravenously or directly via the dialysate have recently been developed to improve efficacy and tolerance. Ferric citrate administered orally can effectively corrects anemia in case of iron deficiency and in addition chelate phosphate in the gut lumen. Ferric carboxymaltose allows intravenous administration of larger doses given less frequently. Ferric pyrophosphate citrate administered directly via the dialysate allows the compensation of iron losses during the hemodialysis session. HIF-prolyl-hydroxylase inhibitors are a new therapeutic class of erythropoiesis-stimulating agents. Orally administered, they act by stabilizing the HIF transcription factor involved in the initiation of erythropoietin production by hypoxia. Several clinical studies have recently evaluated these new molecules in comparison with recombinant EPO. In CKD patients not yet on dialysis or undergoing dialysis therapy non-inferiority in correcting anemia has been demonstrated compared with recombinant EPO. The decrease in circulating hepcidin they induce appears greater than that induced by injectable recombinant EPO. Presently available reports on the safety of HIF-prolyl-hydroxylase inhibitors are reassuring but need to be confirmed in longer-term studies of larger size. © 2022 Published by Elsevier Masson SAS on behalf of Société francophone de néphrologie, dialyse et transplantation.

Efficacy and Safety of Roxadustat in Patients with Chronic Kidney Disease: An Updated Meta-Analysis of Randomized Controlled Trials including 6,518 Patients

Background

Roxadustat is a newly listed oral hypoxia-inducible factor-proline enhancing enzyme inhibitor (HIF-PHI) in recent years. There have been some studies that have proved the efficacy of roxadustat on the treatment of renal anemia in patients with chronic kidney disease (CKD), but there are still different conclusions on its safety.

Methods

PubMed, Embase, Cochrane, and ClinicalTrials were searched for randomized controlled trials (RCTs) that assess efficacy and safety of roxadustat treatment for anemia in CKD patients. The Cochrane Literature Quality Evaluation Scale was used to evaluate the quality of included literature. We choose fixed-effects model or random effects model for data processing based on heterogeneity. It was considered statistically significant when p value <0.05.

Results

A total of 842 articles were retrieved, and 16 trials in the 15 articles were finally included. Roxadustat treatment significantly increased Hb levels. Iron (SMD 1.43, 95% CI 0.31 to 2.55), total iron-binding capacity (SMD 2.06, 95% CI 0.91 to 3.22), ferritin (WMD 21.33, 95% CI 3.04 to 39.62), transferrin saturation (SMD 4.17, 95% CI 3.90 to 4.45), and LDL-cholesterol (SMD -0.64, 95% CI -0.73 to -0.55) showed statistical significance in dialysis-dependent (DD) study. And hepcidin (SMD -1.56, 95% CI -2.63 to -0.50), transferrin (SMD 1.80, 95% CI 1.53 to 2.06), total iron-binding capacity (SMD 1.62, 95% CI 1.39 to 1.86), total cholesterol (SMD -0.88, 95% CI -1.68 to -0.09), ferritin (WMD -52.68, 95% CI -62.68 to -42.67), transferrin saturation (SMD -5.57, 95% CI -7.47 to -3.68), and LDL-cholesterol (SMD -0.85, 95% CI -1.37 to -0.34) showed statistical significance in not dialysis-dependent (NDD) study. In terms of safety, roxadustat treatment did not increase risk of total adverse events either in dialysis-dependent or not dialysis-dependent patients.

Conclusion

Roxadustat can effectively improve anemia in patients with chronic kidney disease. There was no significant difference in total adverse events compared with the control group.

Evolving Strategies in the Treatment of Anaemia in Chronic Kidney Disease: The HIF-Prolyl Hydroxylase Inhibitors

Chronic kidney disease (CKD) affects approximately 10% of the worldwide population; anaemia is a frequent complication. Inadequate erythropoietin production and absolute or functional iron deficiency are the major causes. Accordingly, the current treatment is based on iron and erythropoiesis stimulating agents (ESAs). Available therapy has dramatically improved the management of anaemia and the quality of life. However, safety concerns were raised over ESA use, especially when aiming to reach near-to-normal haemoglobin levels with high doses. Moreover, many patients show hypo-responsiveness to ESA. Hypoxia-inducible factor (HIF) prolyl hydroxylase domain (PHD) inhibitors (HIF-PHIs) were developed for the oral treatment of anaemia in CKD to overcome these concerns. They simulate the body's exposure to moderate hypoxia, stimulating the production of endogenous erythropoietin. Some molecules are already approved for clinical use in some countries. Data from clinical trials showed non-inferiority in anaemia correction compared to ESA or superiority for placebo. Hypoxia-inducible factor-prolyl hydroxylase domain inhibitors may also have additional advantages in inflamed patients, improving iron utilisation and mobilisation and decreasing LDL-cholesterol. Overall, non-inferiority was also shown in major cardiovascular events, except for one molecule in the non-dialysis population. This was an unexpected finding, considering the lower erythropoietin levels reached using these drugs due to their peculiar mechanism of action. More data and longer follow-ups are necessary to better clarifying safety issues and further investigate the variety of pathways activated by HIF, which could have either positive or negative effects and could differentiate HIF-PHIs from ESAs.

Risk of infection in roxadustat treatment for anemia in patients with chronic kidney disease: A systematic review with meta-analysis and trial sequential analysis

Background: Many studies demonstrated that roxadustat (FG-4592) could increase hemoglobin (Hb) levels effectively in anemia patients with chronic kidney disease (CKD). However, its safety remains controversial. This study aims to explore the risk of infection for CKD patients treated with roxadustat, especially focused on sepsis.

Methods: We thoroughly searched for the randomized controlled trials (RCTs) comparing treatment with roxadustat versus erythropoiesis stimulating agents (ESAs) or placebo in PubMed, Embase, Cochrane Library, ClinicalTrials.gov, European Union Clinical Trials Register. Both on and not on dialysis anemia patients with CKD were included. Primary outcomes contained the incidence rates of sepsis. Secondary outcomes included infection-related consequences (septic shock and other infection events), general safety outcomes [all-cause mortality, treatment-emergent adverse events (TEAEs) and treatment-emergent serious adverse events (TESAEs)] and iron parameters. Moreover, a trial sequential analysis (TSA) was conducted to assess if the results were supposed to be a robust conclusion.

Results: Eighteen RCTs (n = 11,305) were included. Overall, the incidence of sepsis (RR: 2.42, 95% CI [1.50, 3.89], p = 0.0003) and cellulitis (RR: 2.07, 95% CI [1.24, 3.44], p = 0.005) were increased in the roxadustat group compared with placebo group. In non-dialysis-dependent (NDD) CKD patients, the incidence of cellulitis (RR 2.01, 95% CI [1.23, 3.28], p = 0.005) was significantly higher in roxadustat group than that in the ESAs or placebo group. Both groups showed similar results in the incidence of septic shock (RR 1.29, 95% CI [0.86, 1.94], p = 0.22). A significant increased risk of all-cause mortality [risk ratios (RR): 1.15, 95% confidence interval (CI) [1.05, 1.26], p = 0.002] was found in roxadustat treatment, and TSA confirmed the result. Compared with ESAs or placebo, both the incident rates of TEAEs (RR:1.03, 95% CI [1.01, 1.04], p = 0.008) and TESAEs (RR: 1.06, 95% CI [1.02, 1.11], p = 0.002) were significantly increased in roxadustat group. As for iron parameters, changes from baseline (Δ) of hepcidin (MD: -26.46, 95% CI [-39.83, -13.09], p = 0.0001), Δ ferritin and Δ TSAT were remarkably lower in the roxadustat group, while Δ Hb, Δ iron and Δ TIBC increased significantly versus those in ESAs or placebo group.

Conclusion: We found evidence that incidence rates of sepsis and cellulitis are higher in roxadustat group compared with placebo. This may be the result of improved iron homeostasis. The risk of all-cause mortality, TEAEs and TESAEs in CKD patients also increased in patients treated with roxadustat. We need more clinical and mechanistic studies to confirm whether roxadustat really causes infection.

Identification and single-base gene-editing functional validation of a cis-EPO variant as a genetic predictor for EPO-increasing therapies

Hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHIs) are currently under clinical development for treating anemia in chronic kidney disease (CKD), but it is important to monitor their cardiovascular safety. Genetic variants can be used as predictors to help inform the potential risk of adverse effects associated with drug treatments. We therefore aimed to use human genetics to help assess the risk of adverse cardiovascular events associated with therapeutically altered EPO levels to help inform clinical trials studying the safety of HIF-PHIs. By performing a genome-wide association meta-analysis of EPO (n = 6,127), we identified a cis-EPO variant (rs1617640) lying in the EPO promoter region. We validated this variant as most likely causal in controlling EPO levels by using genetic and functional approaches, including single-base gene editing. Using this variant as a partial predictor for therapeutic modulation of EPO and large genome-wide association data in Mendelian randomization tests, we found no evidence (at p < 0.05) that genetically predicted long-term rises in endogenous EPO, equivalent to a 2.2-unit increase, increased risk of coronary artery disease (CAD, OR [95% CI] = 1.01 [0.93, 1.07]), myocardial infarction (MI, OR [95% CI] = 0.99 [0.87, 1.15]), or stroke (OR [95% CI] = 0.97 [0.87, 1.07]). We could exclude increased odds of 1.15 for cardiovascular disease for a 2.2-unit EPO increase. A combination of genetic and functional studies provides a powerful approach to investigate the potential therapeutic profile of EPO-increasing therapies for treating anemia in CKD.

Hypoxia-inducible factor stabilisers for the anaemia of chronic kidney disease

BACKGROUND

Anaemia occurs in chronic kidney disease (CKD) and is more prevalent with lower levels of kidney function. Anaemia in CKD is associated with death related to cardiovascular (CV) disease and infection. Established treatments include erythropoiesis-stimulating agents (ESAs), iron supplementation and blood transfusions. Oral hypoxia-inducible factors (HIF) stabilisers are now available to manage anaemia in people with CKD.

OBJECTIVES

We aimed to assess the benefits and potential harms of HIF stabilisers for the management of anaemia in people with CKD.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 22 November 2021 through contact with the Information Specialist using search terms relevant to our review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal, and ClinicalTrials.gov.

SELECTION CRITERIA

Randomised and quasi-randomised studies evaluating hypoxia-inducible factors stabilisers compared to placebo, standard care, ESAs or iron supplementation in people with CKD were included.

DATA COLLECTION AND ANALYSIS

Five authors independently extracted data and assessed the risk of bias. Treatment estimates were summarised using random effects pair-wise meta-analysis and expressed as a relative risk (RR) or mean difference (MD), with a corresponding 95% confidence interval (CI). Evidence certainty was assessed using GRADE.

MAIN RESULTS

We included 51 studies randomising 30,994 adults. These studies compared HIF stabilisers to either placebo or an ESA. Compared to placebo, HIF stabiliser therapy had uncertain effects on CV death (10 studies, 1114 participants): RR 3.68, 95% CI 0.19 to 70.21; very low certainty evidence), and nonfatal myocardial infarction (MI) (3 studies, 822 participants): RR 1.29, 95% CI 0.31 to 5.36; I² = 0%; very low certainty evidence), probably decreases the proportion of patients requiring blood transfusion (8 studies, 4329 participants): RR 0.51, 95% CI 0.44 to 0.60; I² = 0%; moderate certainty evidence), and increases the proportion of patients reaching the target haemoglobin (Hb) (10 studies, 5102 participants): RR 8.36, 95% CI 6.42 to 10.89; I² = 37%; moderate certainty evidence). Compared to ESAs, HIF stabiliser therapy may make little or no difference to CV death (17 studies, 10,340 participants): RR 1.05, 95% CI 0.88 to 1.26; I² = 0%; low certainty evidence), nonfatal MI (7 studies, 7765 participants): RR 0.91, 95% CI 0.76 to 1.10; I² = 0%; low certainty evidence), and nonfatal stroke (5 studies, 7285 participants): RR 1.06, 95% CI 0.71 to 1.56; I² = 8%; low certainty evidence), and had uncertain effects on fatigue (2 studies, 3471 participants): RR 0.80, 95% CI 0.56 to 1.16; I² = 0%; very low certainty evidence). HIF stabiliser therapy probably decreased the proportion of patients requiring blood transfusion (11 studies, 10,786 participants): RR 0.87, 95% CI 0.76 to 1.00; I² = 25%; moderate certainty evidence), but may make little or no difference on the proportion of patients reaching the target Hb (14 studies, 4601 participants): RR 1.00, 95% CI 0.93 to 1.07; I² = 70%; low certainty evidence), compared to ESA. The effect of HIF stabilisers on hospitalisation for heart failure, peripheral arterial events, loss of unassisted dialysis vascular access patency, access intervention, cancer, infection, pulmonary hypertension and diabetic nephropathy was uncertain. None of the included studies reported life participation. Adverse events were rarely and inconsistently reported.

AUTHORS' CONCLUSIONS

HIF stabiliser management of anaemia had uncertain effects on CV death, fatigue, death (any cause), CV outcomes, and kidney failure compared to placebo or ESAs. Compared to placebo or ESAs, HIF stabiliser management of anaemia probably decreased the proportion of patients requiring blood transfusions, and probably increased the proportion of patients reaching the target Hb when compared to placebo.

Clinical parameters among patients in Japan with anemia and non-dialysis-dependent chronic kidney disease with and without diabetes mellitus who received roxadustat

Background

Roxadustat is an oral hypoxia-inducible factor prolyl hydroxylase inhibitor for treating anemia of chronic kidney disease (CKD). This post hoc analysis of a Japanese, open-label, partially randomized, phase 3 study in patients with non-dialysis-dependent (NDD) CKD evaluated disease state–related parameters among patients with and without diabetes mellitus who received roxadustat. In the 1517-CL-0310 study (NCT02988973), roxadustat was noninferior to darbepoetin alfa for change in average hemoglobin levels at Weeks 18–24 from baseline who received roxadustat.

Methods

Patients enrolled in the 1517-CL-0310 study who received roxadustat were included in this post hoc analysis. Hematologic (hemoglobin, reticulocyte/erythrocyte ratio, mean corpuscular volume [MCV], and mean corpuscular hemoglobin [MCH]), iron-related (ferritin, total iron-binding capacity, transferrin, ceruloplasmin, and hepcidin), metabolic (HbA1c, glycated albumin, total cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol), and renal (eGFR) parameters were summarized descriptively by visit through Week 52.

Results

Among 201 included patients, 105 (52.2%) and 96 (47.8%) were in the Diabetes and No Diabetes subgroups, respectively. There were no clinically meaningful differences through Week 52 for most hematologic, iron-related, metabolic, or renal parameters between patients in the Diabetes and No Diabetes subgroups. MCV and MCH remained lower and HbA1c and glycated albumin remained higher in patients in the Diabetes subgroup through Week 52. Both subgroups experienced a similar benefit from roxadustat in maintaining hemoglobin levels in the target range of 10–12 g/dL.

Conclusion

Roxadustat maintained hemoglobin levels in the target range with similar clinical parameters irrespective of diabetes mellitus presence at baseline.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10157-022-02225-w.

WT1: The Hinge Between Anemia Correction and Cancer Development in Chronic Kidney Disease

Hypoxia-inducible factor-prolyl hydroxylase inhibitors (HIF-PHIs) emerge as promising agents to treat anemia in chronic kidney disease (CKD) but the major concern is their correlated risk of cancer development and progression. The Wilms’ tumor gene, WT1, is transcriptionally regulated by HIF and is known to play a crucial role in tumorigenesis and invasiveness of certain types of cancers. From the mechanism of action of HIF–PHIs, to cancer hypoxia and the biological significance of WT1, this review will discuss the link between HIF, WT1, anemia correction, and cancer. We aimed to reveal the research gaps and offer a focused strategy to monitor the development and progression of specific types of cancer when using HIF–PHIs to treat anemia in CKD patients. In addition, to facilitate the long-term use of HIF–PHIs in anemic CKD patients, we will discuss the strategy of WT1 inhibition to reduce the development and progression of cancer.

The efficacy and safety of roxadustat for the treatment of anemia in non-dialysis dependent chronic kidney disease patients: An updated systematic review and meta-analysis of randomized clinical trials

Background

Roxadustat (ROX) is a new medication for anemia as a complication of chronic kidney disease (CKD). Our meta-analysis aims to evaluate the efficacy and safety of ROX, especially on the cardiovascular risks, for anemia in NDD-CKD patients.

Methods

Electronic databases were searched systematically from inception to July 2021 to look for randomized control trials (RCTs) that evaluated ROX NDD-CKD patients. Hemoglobin level and iron utilization parameters, including ferritin, serum iron, transferrin saturation (TSAT), total iron-binding capacity (TIBC), transferrin, and hepcidin were analyzed for efficacy. Pooled risk ratios (RRs) and standardized mean differences (SMDs) were calculated and presented with their 95% confidential intervals (CIs).

Results

Nine RCTs included a total of 3,175 patients in the ROX group and 2,446 patients in the control group. When compared the control group, ROX increased Hb level significantly (SMD: 1.65; 95% CI: 1.08, 2.22; P< 0.00001) and improved iron utilization parameters by decreasing ferritin (SMD: -0.32; 95% CI: -0.51, -0.14; P = 0.0006), TSAT (SMD: -0.19; 95% CI: -0.32, -0.07; P = 0.003), and hepcidin (SMD: -0.74; 95% CI: -1.09, -0.39; P< 0.0001) and increasing TIBC (SMD: 0.99; 95% CI: 0.76, 1.22; P< 0.00001) and transferrin (SMD: 1.20; 95% CI: 0.70, 1.71; P< 0.00001). As for safety, ROX was associated with higher serious adverse effects (RR: 1.07; 95% CI: 1.01, 1.13; P = 0.01), deep venous thrombosis (DVT) (RR: 3.80; 95% CI: 1.5, 9.64; P = 0.08), and hypertension (HTN) (RR: 1.37; 95% CI: 1.13, 1.65; P = 0.001).

Conclusion

We concluded that ROX increased Hb level and improved iron utilization parameters in NDD-CKD patients, but ROX was associated with higher serious adverse effects, especially DVT and HTN. Our results support the use of ROX for NDD-CKD patients with anemia. However, higher-quality RCTs are still needed to ensure its safety and risk of thrombosis.

Randomized Study on the Efficacy of Standard Versus Low Roxadustat Dose for Anemia in Patients on Peritoneal Dialysis

Introduction

We aimed to investigate whether a lower starting dose of roxadustat (∼1–1.4 mg/kg) converted from erythropoiesis-stimulating agent (ESA) could achieve a comparable hemoglobin (Hb) target (≥100 and ≤120 g/l) compared with the standard weight-based dose (∼1.5–2 mg/kg) at week 12 through a peritoneal dialysis (PD) cohort.

Methods

A 12-week multicenter randomized, parallel-controlled, open-label, pilot clinical trial enrolled adult patients who had undergone PD treatment for >3 months with renal anemia. Participants were randomized in blocks of 4 in a 1:1 ratio to either the standard-dose group (n = 50) or the low-dose group (n = 50). The primary end point was the proportion of patients achieving the Hb target at week 12.

Results

Baseline demographic and clinical characteristics of the 2 groups were comparable. There was no difference in the proportion of patients who met the Hb target at week 12, that is, 26 patients (52%) versus 31 patients (62%) in the low-dose group and standard-dose group, respectively (P = 0.31). The Hb levels significantly increased in both groups from baseline to week 12; the median change of Hb levels was 5.0 (0.0–14.3) g/l (P < 0.001) for the standard-dose group and 6.0 (−3.3 to 16.3) g/l for the low-dose group (P = 0.005) (P = 0.581 for between groups).

Conclusion

This study suggests that a lower starting dose of roxadustat effectively achieves the Hb target as standard-dose does among patients on PD. (ClinicalTrials.gov number, NCT04454879).

Two Phase 3 Studies on Ophthalmological Effects of Roxadustat versus Darbepoetin

Introduction

Roxadustat is an orally administered hypoxia-inducible factor (HIF) prolyl hydroxylase inhibitor that represents a novel therapeutic option for patients with anemia of chronic kidney disease (CKD).

Methods

Conducted in Japan, CL-0307 (NCT02952092) and CL-310 (NCT02988973) were phase 3, darbepoetin alfa (DA)-controlled studies conducted in dialysis-dependent (DD) and non–DD (NDD) patients with CKD, respectively, where patients were randomized to receive roxadustat or DA. Ophthalmic imaging and assessments of visual acuity were performed up to week 24 or at study discontinuation. Ophthalmic imaging was centrally evaluated by independent readers masked to the study treatment.

Results

In CL-0307, 302 patients (roxadustat, n = 150; DA, n = 152) received ≥1 dose of the study drug and were included in this analysis. In CL-0310, 262 patients (roxadustat, n = 131; DA, n = 131) received ≥1 dose of the study drug and were included in this analysis. Proportions of DD patients with new or worsening retinal hemorrhages (RHs) in the roxadustat group and DA group were 32.4% (46 of 142) and 36.6% (53 of 145), respectively. Proportions of NDD patients with CKD with new or worsening RH in the roxadustat and DA groups were 31.4% (38 of 121) and 39.8% (51 of 128), respectively. Similar trends were apparent in subgroup analyses: patients with/without RH at baseline and with/without diabetes mellitus at baseline. In both studies, there were no differences in retinal thickness, visual acuity, presence of hard exudates or cotton wool spots, or presence of intra- and subretinal fluid between groups, at any given time point.

Conclusion

In these studies, roxadustat, compared with DA, was not associated with an increased risk of adverse ophthalmologic events in these cohorts.

Current Status of Renal Anemia Pharmacotherapy-What Can We Offer Today

Chronic kidney disease (CKD) is one of the fastest-growing major causes of death internationally. Better treatment of CKD and its complications is crucial to reverse this negative trend. Anemia is a frequent complication of CKD and is associated with unfavorable clinical outcomes. It is a devastating complication of progressive kidney disease, that negatively affects also the quality of life. The prevalence of anemia increases in parallel with CKD progression. The aim of this review is to summarize the current knowledge on therapy of renal anemia. Iron therapy, blood transfusions, and erythropoietin stimulating agents are still the mainstay of renal anemia treatment. There are several novel agents on the horizon that might provide therapeutic opportunities in CKD. The potential therapeutic options target the hepcidin–ferroportin axis, which is the master regulator of iron homeostasis, and the BMP-SMAD pathway, which regulates hepcidin expression in the liver. An inhibition of prolyl hydroxylase is a new therapeutic option becoming available for the treatment of anemia in CKD patients. This new class of drugs stimulates the synthesis of endogenous erythropoietin and increases iron availability. We also summarized the effects of prolyl hydroxylase inhibitors on iron parameters, including hepcidin, as their action on the hematological parameters. They could be of particular interest in the out-patient population with CKD and patients with ESA hyporesponsiveness. However, current knowledge is limited and still awaits clinical validation. One should be aware of the potential risks and benefits of novel, sophisticated therapies.