Efficacy and Cardiovascular Safety of Roxadustat for Treatment of Anemia in Patients with Non-Dialysis-Dependent CKD: Pooled Results of Three Randomized Clinical Trials

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.

Combined dapagliflozin and roxadustat effectively protected heart and kidney against cardiorenal syndrome-induced damage in rodent through activation of cell stress-Nfr2/ARE signalings and stabilizing HIF-1α

BACKGROUND

This study tested whether combined dapagliflozin (DAPA) and roxadustat (ROX) therapy was superior to a singular therapy in protecting heart and kidney functions in rats with cardiorenal syndrome (CRS).

METHODS AND RESULTS

An in vitro study demonstrated that the cell survival (PI3K/Akt/mTOR)/cell stress (ERK1/2, JNK/p-38) signaling was significantly activated by combination therapy with ROX-DAPA (all p<0.001). Additionally, these two signaling pathways further significantly upregulated the hypoxia-induced factor (HIF)-1α which, in turn, significantly upregulated Nrf2/ARE (HO-1/NQO-1) and angiogenesis/cell-growth factors (EPO/SDF-1α/VEGF/FGF/IGF-2) and downregulated hypoxia-inducible factor prolyl-4-hydroxylase-1 (all p<0.001). Adult-male SD rats were categorized into Groups 1 (sham-operated control)/2 (CRS)/3 (CRS+ROX)/4 (CRS+DAPA)/5 (CRS+ROX+DAPA). By Day 60 after rodent CRS induction, the levels of BUN/creatinine and the ratio of urine protein to creatinine were lowest in Group 1, highest in Group 2, and significantly lower in Group 5 than in Groups 3 and 4; however, they were similar in the latter two groups, whereas the left-ventricular-ejection-fraction exhibited the opposite trend of creatinine among the groups (all p<0.0001). The protein expression levels of cell-survival (p-PI3K/p-Akt-p-mTOR)/cell-stress (p-JNK/p-p38/p-ERK1/2)/Nrf2-ARE (HO-1/NQO-1/SIRT1/SIRT3) signaling factors and angiogenesis factors (HIF-1α/VEGF/SDF-1α/FGF/IGF-2/EPO) significantly and progressively increased from Groups 1-5 (all p<0.0001).

CONCLUSION

Combined DAPA-ROX therapy has a synergistic effect on protecting heart and kidney functions against CRS-induced damage in rodents.

Roxadustat for Treating Anemia in Patients with Advanced Chronic Kidney Disease Not Undergoing Dialysis: A Retrospective Study

Objective Roxadustat, a hypoxia-inducible factor-prolyl hydroxylase inhibitor, increases the hemoglobin (Hb) levels in patients with chronic kidney disease (CKD). To date, limited clinical studies have focused on the excessive increase in the Hb levels in the early weeks after switching from erythropoiesis-stimulating agents (ESA) to roxadustat in adult non-dialysis patients. We conducted a retrospective study to examine whether early overshoot frequently occurs after switching to roxadustat. Methods This 8-week retrospective pilot study examined patients with anemic, non-dialyzed CKD who switched from ESA (darbepoetin or epoetin beta pegol) to roxadustat or continued ESA. The Hb levels >12.5 g/dL after starting our observation was defined as Hb overshoot. Patients: Twenty-three patients who switched to roxadustat (roxadustat group) and 63 who continued ESA (ESA group) were included. Results The baseline median estimated glomerular filtration rate and mean Hb levels were 15.7 mL/min/1.73 mShizuokax and 10.77 g/dL in roxadustat group and 15.2 mL/min/1.73 m2 and 10.64 g/dL in ESA group, respectively. Eight patients (34.8%) in the roxadustat group and two patients (3.2%) in the ESA group had Hb overshoot within the 8-week visit (odds ratio: 20.2 [95% confidence interval 3.13-130.0, p<0.01] in the background adjusted model). Among the patients with Hb overshoot in the roxadustat group, the Hb levels were maintained close to baseline 4 weeks after roxadustat discontinuation. A younger age and higher baseline Hb and Hct levels were risk factors for Hb overshoot. Conclusions Hb overshoot was frequently observed in patients switched to roxadustat. Clinicians should be aware of Hb overshoot and emphasize the importance of early Hb level checks.

Hypoxia-inducible factor prolyl hydroxylase inhibitors for anaemia in chronic kidney disease: a clinical practice document by the European Renal Best Practice board of the European Renal Association

Anaemia is a common complication of chronic kidney disease (CKD) and is associated with poor long-term outcomes and quality of life. The use of supplemental iron, erythropoiesis-stimulating agents (ESAs) and blood transfusions has been the mainstay for treatment of anaemia in CKD for more than 3 decades. Despite available treatments, CKD patients with anaemia are undertreated and moderate-severe anaemia remains prevalent in the CKD population. Anaemia has consistently been associated with greater mortality, hospitalization, cardiovascular events and CKD progression in CKD patients, and the risk increases with anaemia severity. Hypoxia-inducible factor (HIF) prolyl hydroxylase (PH) inhibitors have a novel mechanism of action by mimicking the body's response to hypoxia and have emerged as an alternative to ESAs for treatment of anaemia in CKD. Their efficacy in correcting and maintaining haemoglobin has been demonstrated in >30 phase 3 clinical trials. Additionally, HIF activation results in various pleiotropic effects beyond erythropoiesis, with cholesterol reduction and improved iron homeostasis and potential anti-inflammatory effects. The long-term safety of these agents, particularly with respect to cardiovascular and thromboembolic events, and their possible effect on tumour growth needs to be fully elucidated. This article presents in detail the effects of HIF-PH inhibitors, describes their mechanisms of action and pharmacologic properties and discusses their place in the treatment of anaemia in CKD according to the available evidence.

Hypoxia-Inducible Factor Prolyl Hydroxylase Inhibitors in Kidney Disease

BACKGROUND

Hypoxia-inducible factor (HIF) prolyl hydroxylase inhibitors are an oral treatment for anemia of chronic kidney disease (CKD). In this systematic review and meta-analysis, we assessed long-term safety of HIF prolyl hydroxylase inhibitors.

METHODS

We searched MEDLINE, Embase, and Cochrane databases for randomized trials comparing HIF prolyl hydroxylase inhibitors with an erythropoiesis-stimulating agent (ESA) or placebo with greater than or equal to 48 weeks of follow-up. The primary outcome was major adverse cardiovascular event (MACE), defined as a composite of all-cause death, myocardial infarction, or stroke. Treatment effects were pooled using random-effects models.

RESULTS

Twenty-five trials involving 26,478 participants were included. Of these, 13 trials enrolled 13,230 participants with dialysis-dependent CKD, and 12 trials enrolled 13,248 participants with nondialysis-dependent CKD. There was no evidence that HIF prolyl hydroxylase inhibitors and ESA had different effects on MACE in people with dialysis-dependent CKD (risk ratio, 0.99; 95% confidence interval [CI], 0.92 to 1.08) or people with nondialysis-dependent CKD (risk ratio, 1.08; 95% CI, 0.95 to 1.22). Similarly, there was no evidence that HIF prolyl hydroxylase inhibitors and placebo had different effects on MACE (risk ratio, 1.10; 95% CI, 0.96 to 1.27) in people with nondialysis-dependent CKD. The lack of difference between HIF prolyl hydroxylase inhibitors and ESA or placebo was observed for individual components of MACE and cardiovascular death. Safety of HIF prolyl hydroxylase inhibitors for other outcomes was comparable with ESA in dialysis-dependent CKD. In nondialysis-dependent CKD, dialysis access thrombosis, venous thromboembolism, infections, and hyperkalemia occurred more frequently with HIF prolyl hydroxylase inhibitors in placebo-controlled trials but not in ESA-controlled trials.

CONCLUSIONS

There was no evidence of a difference in the long-term cardiovascular safety profile of HIF prolyl hydroxylase inhibitors and ESA in adults with dialysis-dependent CKD and adults with nondialysis-dependent CKD. (PROSPERO registration number, CRD42021278011.).

Hypoxia-Inducible Factor Prolyl Hydroxylase Inhibitors as a New Treatment Option for Anemia in Chronic Kidney Disease

Anemia plays an important role in chronic kidney disease (CKD) progression because it worsens the quality of life and increases the risk of cardiovascular complications in CKD patients. In such cases, anemia is mainly caused by endogenous erythropoietin (EPO) and iron deficiencies. Therefore, KDIGO and ERBP guidelines for anemia treatment in CKD patients focus on recombinant EPO and iron supplementation. A recent new treatment option for anemia in CKD patients involves blocking the hypoxia-inducible factor (HIF) system with prolyl hydroxylase inhibitors (PHIs), what causes increasing endogenous EPO production and optimizing the use of iron. Clinical studies have shown that the hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHIs) covered in this manuscript-roxadustat, vadadustat, daprodustat, and molidustat-effectively increase hemoglobin (Hb) levels in both non-dialyzed and dialyzed CKD patients. Moreover, these medicines reduce blood lipid levels and do not accelerate CKD progression. However, blockage of the HIF system by HIF-PHIs may be associated with adverse effects such as cardiovascular complications, tumorogenesis, hyperkalemia. and retinopathy. More extensive and long-term clinical trials of HIF-PHIs-based anemia treatment in CKD patients are needed, and their results will indicate whether HIF-PHIs represent an effective and safe alternative to EPO and iron supplementation for anemia treatment in CKD patients.

The Comparison between Vadadustat and Daprodustat Regarding Dose, Cost, and Safety of Treatment for Renal Anemia in Non-dialysis Patients with Chronic Kidney Diseases

Objective We retrospectively compared the dose, cost, and safety of vadadustat and daprodustat for the treatment of renal anemia in patients with chronic kidney diseases who were not undergoing dialysis. Methods The primary outcome of this study was the change in dose and cost from the initiation of vadadustat and daprodustat treatment. The secondary outcome was the drug safety. Patients We treated 30 patients each with the hypoxia-inducible factor prolyl-hydroxylase inhibitors (HIF-PHIs) daprodustat and vadadustat. The hemoglobin (Hb) concentration was targeted at 11-13 g/dL, and transferrin saturation was maintained at ≥20%, as per the 2018 Japanese guidelines for the diagnosis and treatment of chronic kidney disease. Results Hb levels increased from 10.7 to 11.5 g/dL after the first month of daprodustat administration, whereas those for vadadustat patients remained relatively stable, going from 10.7 to 10.6 g/dL. After six months, the Hb level reached 12.1 g/dL and 11.3 g/dL for daprodustat and vadadustat, respectively. The dosage of vadadustat was significantly increased by 46% and 70% after 3 and 12 months, respectively, compared with the initial doses, whereas that of daprodustat did not change substantially. The average cost of vadadustat also increased in the first 3 months and remained over 500 yen/day after 3 months, while that of daprodustat showed little change from the initial cost of 360 yen/day. Conclusion These results suggest that heterogeneity exists in the drug potency and dosage required for treatment between daprodustat and vadadustat. Serious adverse events [death, cardiovascular disease, end stage renal disease (ESRD), and malignancy] occurred in more than 20% of participants with both HIF-PHIs. Further studies are required to confirm the safety of HIF-PHIs.

BMSC loaded photo-crosslinked hyaluronic acid/collagen hydrogel incorporating FG4592 for enhanced cell proliferation and nucleus pulposus differentiation

Intervertebral disc degeneration arises from damage or degeneration of the nucleus pulposus (NP). In this study, we developed a photo-crosslinkable hydrogel incorporating FG4592 to support the growth and differentiation of bone-marrow-derived mesenchymal stem cells (BMSC). Initially, hyaluronic acid was modified with tyramine and combined with collagen to introduce riboflavin as a photo-crosslinker. This hydrogel transitioned from liquid to gel upon exposure to blue light in 3 min. The results showed that the hydrogel was biodegradable and had mechanical properties comparable to those of human NP tissues. Scanning electron microscopy after BMSC seeding in the hydrogel revealed an even distribution, and cells adhered to the collagen fibers in the hydrogel with minimal cell mortality. The effect of FG4592 on BMSC proliferation and differentiation was examined, revealing the capability of FG4592 to promote BMSC proliferation and direct differentiation resembling human NP cells. After cultivating BMSCs in the photo-crosslinked hydrogel, there was an upregulation in the expression of glycosaminoglycans, aggrecan, type II collagen, and keratin 19 proteins. Cross-species analyses of rat and human BMSCs revealed consistent results. For potential clinical applications, BMSC loaded with photo-crosslinked hydrogels can be injected into damaged intervertebral disc to facilitate NP regeneration.

Assessment of the safety of Roxadustat for cardiovascular events in chronic kidney disease-related anemia using meta-analysis and bioinformatics

Objective

This study compares the cardiovascular risk in anemic chronic kidney disease patients treated with Roxadustat versus erythropoietin stimulating agents (ESAs). It also explores the cardiovascular impact of Roxadustat.

Methods

We searched PubMed, EMBASE, Cochrane, Scopus, and Web of Science databases up to 13 August 2023, using terms such as "ESA," "Roxadustat," "MACE," "stroke," "death," "myocardial infarction," and "heart failure." Two researchers independently selected and extracted data based on predefined criteria. We assessed the risk of bias with the Cochrane tool and analyzed statistical heterogeneity using the Q and I2 tests. We conducted subgroup analyses by geographical region and performed data analysis with Stata 14.0 and RevMan 5.4 software. Data were sourced from the NCBI database by filtering for "Roxadustat" and "human," and differentially expressed genes were identified using R software, setting the significance at p < 0.01 and a 2-fold logFC, followed by GO enrichment analysis, KEGG pathway analysis, and protein interaction network analysis.

Results

A total of 15 articles encompassing 1,43,065 patients were analyzed, including 1,38,739 patients treated with ESA and 4,326 patients treated with Roxadustat. In the overall population meta-analysis, the incidences of Major Adverse Cardiovascular Events (MACE), death, and heart failure (HF) were 13%, 8%, and 4% in the Roxadustat group, compared to 17%, 12%, and 6% in the ESA group, respectively, with P-values greater than 0.05. In the subgroup analysis, the incidences were 13%, 11%, and 4% for the Roxadustat group versus 17%, 15%, and 5% for the ESA group, also with p-values greater than 0.05. Bioinformatics analysis identified 59 differentially expressed genes, mainly involved in the inflammatory response. GO enrichment analysis revealed that these genes are primarily related to integrin binding. The main pathways identified were the TNF signaling pathway, NF-κB signaling pathway, and lipid metabolism related to atherosclerosis. The protein interaction network highlighted IL1B, CXCL8, ICAM1, CCL2, and CCL5 as the top five significantly different genes, all involved in the inflammatory response and downregulated by Roxadustat, suggesting a potential role in reducing inflammation.

Conclusion

The meta-analysis suggests that the use of Roxadustat and ESA in treating anemia associated with chronic kidney disease does not significantly alter the likelihood of cardiovascular events in the overall and American populations. However, Roxadustat exhibited a safer profile with respect to MACE, death, and heart failure. The bioinformatics findings suggest that Roxadustat may influence integrin adhesion and affect the TNF and NF-κB signaling pathways, along with lipid and atherosclerosis pathways, potentially reducing inflammation.

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.

Daprodustat and Heart Failure in CKD

Key Points

Patients with CKD face meaningful risk of heart failure hospitalization. Daprodustat compared with darbepoetin was associated with a nonsignificantly greater number of heart failure hospitalizations in non-dialysis patients.

Background

Patients with CKD are at higher risk of heart failure. The hypoxia-inducible factor prolyl hydroxylase inhibitor daprodustat is an orally acting alternative to conventional injectable erythropoietin-stimulating agents (ESAs) for the treatment of anemia in patients with CKD. Whether daprodustat affects the risk of heart failure hospitalization is unknown.

Methods

The Anemia Studies in Chronic Kidney Disease: Erythropoiesis via a Novel Prolyl Hydroxylase Inhibitor Daprodustat–Dialysis (ASCEND-D; n =2964) and Anemia Studies in Chronic Kidney Disease: Erythropoiesis via a Novel Prolyl Hydroxylase Inhibitor Daprodustat–Non-Dialysis (ASCEND-ND; n =3872) trials compared daprodustat with conventional ESA in patients with anemia of CKD who did or did not require dialysis, respectively. We identified risk factors of heart failure hospitalization and assessed the effect of daprodustat compared with conventional ESA on heart failure hospitalizations.

Results

History of heart failure, diabetes, and higher systolic BP were independently associated with heart failure hospitalization in both trials, irrespective of treatment assignment. The number of first heart failure hospitalizations was greater in the daprodustat arm in patients not receiving dialysis (hazard ratio [HR], 1.22 [95% confidence interval (CI), 0.95 to 1.56], P = 0.12) and in patients receiving dialysis (HR, 1.10 [95% CI, 0.84 to 1.45], P = 0.47), although these differences were not statistically significant. HRs in patients with and without history of heart failure were 1.37 (95% CI, 0.89 to 2.11) versus 1.08 (95% CI, 0.79 to 1.46) (P -interaction=0.36) in the ASCEND-ND trial and 1.52 (95% CI, 0.97 to 2.38) versus 0.93 (95% CI, 0.66 to 1.30) (P -interaction=0.09) in the ASCEND-D trial, respectively. In post hoc analyses, daprodustat increased total (first and recurrent) heart failure hospitalizations in participants not receiving dialysis (rate ratio, 1.46 [95% CI, 1.11 to 1.92], P = 0.007) but not in participants receiving dialysis (rate ratio, 1.01 [95% CI, 0.74 to 1.39], P = 0.93). Daprodustat did not significantly affect the risk of a composite outcome of first heart failure hospitalization or death.

Conclusions

A greater number of first heart failure hospitalization events occurred in patients treated with daprodustat compared with conventional ESA, but this difference did not reach statistical significance. Differences in the number of heart failure hospitalization events were most apparent in patients not receiving dialysis and in patients with history of heart failure.

Podcast

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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.

Targeting hypoxia-inducible factors: therapeutic opportunities and challenges

Hypoxia-inducible factors (HIFs) are highly conserved transcription factors that are crucial for adaptation of metazoans to limited oxygen availability. Recently, HIF activation and inhibition have emerged as therapeutic targets in various human diseases. Pharmacologically desirable effects of HIF activation include erythropoiesis stimulation, cellular metabolism optimization during hypoxia and adaptive responses during ischaemia and inflammation. By contrast, HIF inhibition has been explored as a therapy for various cancers, retinal neovascularization and pulmonary hypertension. This Review discusses the biochemical mechanisms that control HIF stabilization and the molecular strategies that can be exploited pharmacologically to activate or inhibit HIFs. In addition, we examine medical conditions that benefit from targeting HIFs, the potential side effects of HIF activation or inhibition and future challenges in this field.

Impact of HIF prolyl hydroxylase inhibitors in heart failure patients with renal anemia

OBJECTIVE

Hypoxia-inducible factor prolyl hydroxylase (HIF-PH) inhibitors are a new class of anti-anemia agents. We retrospectively evaluated the safety and efficacy of HIF-PH inhibitors in patients with heart failure (HF) complicated by anemia associated with chronic kidney disase. HIF-PH inhibitor treatment was initiated in 32 patients with chronic HF complicated by renal anemia and were followed up for 3 months.

RESULTS

Hematocrit and hemoglobin levels markedly improved 3 months after HIF-PH inhibitor treatment. However, levels of NT-proBNP, which is an indicator of HF, did not decrease considerably. Based on the rate of change in NT-proBNP, we divided the patients into "responder" and "non-responder" groups. The results showed that considerably more patients had a ferritin level of less than 100 ng/mL in the non-responder group at baseline. There were substantially more patients with TSAT of less than 20% in the non-responder group at 1 month after HIF-PH inhibitor treatment. The cut-off values to maximize the predictive power of ferritin level at baseline and TSAT value at 1 month after treatment were 41.8 ng/ml and 20.75. HIF-PH inhibitor treatment can be expected to be effective for improving both anemia and HF if ferritin≥41.8 ng/ml at baseline or TSAT≥20.75 at 1 month after treatment.

Retrospective study on the effect of Niaoduqing particles on outcome of non-diabetic patients with stage IV chronic kidney disease

This study was to investigate the improvement value of Niaoduqing particles in the outcome of non-diabetic patients with stage IV chronic kidney disease (CKD). The non-diabetic patients with stage IV CKD who were to receive Niaoduqing particles were set as the study group (252 cases), and the patients with the same disease who only received Western medicine in the public database were set as the control group (220 cases). The follow-up visits were 3 months/time for 1 year. Deaths due to various causes, doubling of creatinine levels, and end-stage renal disease were used as hard end points to stop follow-up. The clinical indexes of the 2 groups were observed and compared. The results showed that the rate of compound outcome was significantly lower in the study group (28.17%) than in the control group (36.82%), the glomerular filtration rate was significantly higher than that in the control group, and the levels of uric acid and urea were significantly lower than that in the control group (P < .05). Niaoduqing particles can reduce creatinine and urea nitrogen, stabilize renal function, delay dialysis time, and improve the incidence of compound outcome in patients with non-diabetic stage IV CKD, which is worthy of clinical promotion.

A phase 3b, multicenter, open-label, single-arm study of roxadustat within a US dialysis organization: The DENALI study

INTRODUCTION

Roxadustat is an oral hypoxia-inducible factor prolyl hydroxylase inhibitor approved in several regions for the treatment of anemia of chronic kidney disease (CKD). DENALI, a phase 3b study, evaluated the efficacy, safety, and feasibility of roxadustat in patients with anemia of CKD receiving in-center or home dialysis.

METHODS

Eligible patients received open-label roxadustat, dosed three times weekly for 24 weeks, with an optional extension of ≤1 year. Initial dosing depended on erythropoiesis-stimulating agent (ESA) dose at screening for patients receiving ESAs (≥6 weeks) and weight-based for those not (total <6 weeks). Primary efficacy endpoints were proportion of patients with mean hemoglobin (Hb) ≥10.0 g/dL averaged over Weeks 16-24, and mean Hb change from baseline to the average during Weeks 16-24. Treatment-emergent adverse events (TEAEs) and treatment-emergent serious adverse events (TESAEs) were assessed.

FINDINGS

Of 281 patients screened, 203 were treated and 201 included in the full analysis set. Overall, 166 patients completed the 24-week treatment period and 126 continued into the extension period. Mean baseline Hb was 10.4 g/dL and 82.6% received in-center hemodialysis. Overall, 84.6% of patients achieved a mean Hb ≥ 10.0 g/dL averaged Weeks 16-24. Mean (standard deviation) Hb change from baseline averaged Weeks 16-24 was 0.5 (1.0) g/dL. Prespecified subgroup analyses were consistent with primary analyses. Dosing adherence was 94%. Overall, 3.0% of patients received a red blood cell transfusion at up to Week 24. TEAEs and TESAEs were reported by 71.4% and 25.6% of patients, respectively. The most frequently reported TESAEs were COVID-19 (n = 5; 2.5%), and acute myocardial infarction, pneumonia, and sepsis (each n = 4; 2.0%).

DISCUSSION

Roxadustat effectively achieved and/or maintained mean Hb levels ≥10.0 g/dL in patients receiving dialysis. The feasibility of incorporating oral roxadustat into dialysis organizations was successfully demonstrated with high dosing adherence. No new safety signals were identified.

The anaemia treatment journey of CKD patients: from epoetins to hypoxia-inducible factor-prolyl hydroxylase inhibitors

The discovery and development of erythropoiesis-stimulating agents was a journey lasting more than a century, leading to the cloning and approval of recombinant human erythropoietin (rHuEpo). This was an impressive clinical advance, providing the possibility of correcting the symptoms associated with anaemia in chronic kidney disease. Associated iron use was needed to produce new haemoglobin-containing blood red cells. Partial anaemia correction became the standard of care since trials aiming for near-normal haemoglobin levels showed a higher risk of adverse cardiovascular events. Hoping to reduce the cardiovascular risks, a new category of drugs was developed and tested. Hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHIs) are small molecules than can be formulated into orally active pills. They simulate reduced tissue oxygen pressure, thus stimulating the production of endogenous erythropoietin (Epo) by the kidneys and liver. Clinical trials with these compounds demonstrated that HIF-PHIs are at least as effective as rHuEpo in treating or correcting anaemia in non-dialysis and dialysis patients. Trials with HIF-PHIs did not demonstrate superiority in safety outcomes and in some trials, outcomes were worse. There was also a focus on oral delivery, a possible beneficial iron-sparing effect and the ability to overcome Epo resistance in inflamed patients. A negative effect is possible iron depletion, which may explain adverse outcomes.

A phase 3b, multicenter, open-label, single-arm study of roxadustat (ASPEN): Operational learnings within United States dialysis organizations

INTRODUCTION

Roxadustat is an oral hypoxia-inducible factor prolyl hydroxylase inhibitor approved in several regions for the treatment of anemia of chronic kidney disease (CKD). ASPEN evaluated the efficacy, safety, and feasibility of roxadustat in patients with anemia of CKD in US dialysis organizations.

METHODS

This open-label, single-arm study (NCT04484857) comprised a 6-week screening period, followed by 24 weeks of treatment (with optional extension ≤1 year) and a 4-week follow-up. Patients aged ≥18 years, receiving chronic dialysis, with hemoglobin (Hb) 9.0-12.0 g/dL if converting from erythropoiesis-stimulating agents (ESAs), or <10.0 g/dL if receiving ESAs for <6 weeks, received oral roxadustat three times weekly in-center. Primary efficacy endpoints included proportion of patients with mean Hb ≥10 g/dL, averaged over weeks 16-24, and mean Hb change from baseline to the average over weeks 16-24. Safety was also assessed.

FINDINGS

Overall, 283 patients were enrolled and treated, 282 (99.6%) were included in the full analysis set, and 216 (76.3%) continued into the extension period. Most patients enrolled were from DaVita sites (71%), with the rest from US Renal Care sites (29%). Mean (standard deviation [SD]) baseline Hb was 10.6 (0.7) g/dL. Nearly all patients were prior ESA users (n = 274; 97.2%). The proportion of patients with mean Hb ≥10 g/dL during weeks 16-24 was 83.7% (95% confidence interval 78.9-88.6). Mean (SD) Hb increase from baseline to the average over weeks 16-24 was 0.2 (1.0) g/dL. During the treatment period, 82 (29.0%) patients reported treatment-emergent serious adverse events (TESAEs). The most common TESAEs were COVID-19 pneumonia (n = 10; 3.5%), acute respiratory failure (n = 9; 3.2%), COVID-19 (n = 7; 2.5%), acute myocardial infarction (n = 7; 2.5%), and fluid overload (n = 6, 2.1%).

DISCUSSION

Roxadustat was effective in maintaining Hb in patients with anemia of CKD on dialysis in large, community-based dialysis organizations.

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.

Cardiovascular safety of current and emerging drugs to treat anaemia in chronic kidney disease: a safety review

INTRODUCTION

Erythropoiesis-stimulating agents (ESAs) are the standard of treatment for anemia in chronic kidney disease. Hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHI) are small molecules that stimulate endogenous erythropoietin synthesis.

AREAS COVERED

The cardiovascular safety of ESAs and HIF-PHIs. We performed a PubMed search using several key words, including anemia, chronic kidney disease, safety, erythropoiesis stimulating agents, HIF-PH inhibitors.

EXPERT OPINION

ESAs are well-tolerated drugs with a long history of use; there are safety concerns, especially when targeting high hemoglobin levels. HIF-PHIs have comparable efficacy to ESAs in correcting anemia. Contrary to expectations, randomized phase 3 clinical trials have shown that overall HIF-PHIs were non-inferior to ESA or placebo with respect to the risk of cardiovascular endpoints. In addition, some phase 3 trials raised potential safety concerns regarding cardiovascular and thrombotic events, particularly in non-dialysis patients.Today, HIF-PHIs represent an additional treatment option for anemia in patients with chronic kidney disease. This has made the management of anemia in CKD more complex and heterogeneous. A better understanding of the mechanisms causing hypo-responsiveness to ESAs, combined with an individualized approach that balances ESAs, HIF-PHIs and iron doses, could increase the benefits while reducing the risks.

Comparison between the influence of roxadustat and recombinant human erythropoietin treatment on blood pressure and cardio-cerebrovascular complications in patients undergoing peritoneal dialysis

Introduction

Roxadustat treatment in PD patients is equivalent to ESAs in increasing hemoglobin (Hb). But blood pressure, cardiovascular parameters, cardio-cerebrovascular complications and prognosis in the two groups before and after treatment has not been sufficiently discussed.

Methods

Sixty PD patients who were treated with roxadustat for renal anemia in our PD center recruited from June 2019 to April 2020 as roxadustat group. PD patients treated with rHuEPO were enrolled at a 1:1 ratio as rHuEPO group using the method of propensity score matching. Hb, blood pressure, cardiovascular parameters, cardio-cerebrovascular complications and prognosis were compared between the two group. All patients were followed up for at least 24 months.

Results

There were no significant differences in baseline clinical data or laboratory values between roxadustat group and rHuEPO group. After 24 months of follow-up, there was no significant difference in Hb levels (p > 0.05). There were no significant changes in blood pressure, or the incidence of nocturnal hypertension before and after treatment in roxadustat group (p > 0.05), while blood pressure significantly increased in rHuEPO group after treatment (p < 0.05). Compared with roxadustat group after follow-up, rHuEPO group had a higher incidence of hypertension, the levels of cardiovascular parameters were worse and cardio-cerebrovascular complications had a higher incidence (p < 0.05). Cox regression analysis showed age, systolic blood pressure, fasting blood glucose, and rHuEPO use before baseline were risk factors for cardio-cerebrovascular complications in PD patients, while treatment with roxadustat was a protective factor for cardiovascular and cerebrovascular complications.

Conclusion

Compared with rHuEPO, roxadustat had less influence on blood pressure or cardiovascular parameters, and it was associated with a lower risk of cardio-cerebrovascular complications in patients undergoing PD. Roxadustat has a cardio-cerebrovascular protective advantage in PD patients with renal anemia.

A critical review of Roxadustat formulations, solid state studies, and analytical methodology

This review aims to collate information about the analytical methodologies, bioanalytical methodologies, pharmaceutical formulations, solid-state studies, and the current and future market scenario for a relatively new class of drugs, Roxadustat. Roxadustat is a hypoxia-inducible factor propyl hydroxylase inhibitor that significantly increases blood hemoglobin via the action of transcriptional activator HIF. As the molecule has a promising role in stimulating erythropoiesis, it is considered an ideal therapeutic agent for patients with anemia. In the current review, an attempt has been made to compile the pharmacological, pharmacokinetic, and pharmacodynamic characteristics of Roxadustat and systematically present product development data. This drug has several polymorphs of cocrystal, co-former, and salt, which have been explained in detail in the current work. The comprehensive review summarizes all the chromatographic methods and is presented in table form. This review has extensively covered Liquid chromatography-tandem mass spectrometry methods used to analyze Roxadustat in the biological matrix. The literature needs more data on forced degradation study, impurity profiling, gas chromatography, analytical methods for assay, dissolution, and different formulation aspects of Roxadustat.

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].

Effects of hypoxia-inducible factor prolyl hydroxylase inhibitors versus erythropoiesis-stimulating agents on iron metabolism and inflammation in patients undergoing dialysis: A systematic review and meta-analysis

Aims

This study aimed to evaluate the effects of hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHIs) on iron metabolism and inflammation in dialysis-dependent chronic kidney disease (DD-CKD) patients.

Methods

PubMed, Embase, Web of Science, Cochrane Library, and ClinicalTrials.gov websites were searched for randomized controlled trials (RCTs) investigating HIF-PHIs versus ESAs for DD-CKD patients.

Key findings

Twenty studies with 14,737 participants were included in the meta-analysis, which demonstrated no significant difference in the effect of transferrin saturation and ferritin between HIF-PHIs and the ESAs group (MD, 0.65; 95%CI, -0.45 to 1.75; very low certainty; SMD, -0.03; 95% CI, -0.13 to 0.07; low certainty). However, HIF-PHIs significantly increased the iron (MD, 2.30; 95% CI, 1.40 to 3.20; low certainty), total iron-binding capacity (SMD, 0.82; 95% CI, 0.66 to 0.98; low certainty), and transferrin (SMD, 0.90; 95%CI, 0.74 to 1.05; moderate certainty) levels when compared with the ESAs group. In contrast, the hepcidin level and dosage of intravenous iron were significantly decreased in the HIF-PHIs group compared with the ESAs group (MD, -15.06, 95%CI, -21.96 to -8.16; low certainty; MD, -18.07; 95% CI, -30.05 to -6.09; low certainty). The maintenance dose requirements of roxadustat were independent of baseline CRP or hsCRP levels with respect to the effect on inflammation.

Significance

HIF-PHIs promote iron utilization and reduce the use of intravenous iron therapy. Furthermore, HIF-PHIs, such as roxadustat, maintain the erythropoietic response independent of the inflammatory state. Thus, HIF-PHIs may be an alternative treatment strategy for anemia in DD-CKD patients, where ESA is hyporesponsive due to iron deficiency and inflammation.

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.

The roles of HIF-1α signaling in cardiovascular diseases

Oxygen is essential for living organisms. Molecular oxygen binds to hemoglobin and is delivered to every organ in the body. In several cardiovascular diseases or anemia, local oxygen tension drops below its physiological level and tissue hypoxia develops. In such conditions, the expression of hypoxia-responsive genes increases to alleviate the respective condition. The hypoxia-responsive genes include the genes coding erythropoietin (EPO), vascular endothelial growth factor-A, and glycolytic enzymes. Hypoxia-inducible factor (HIF)-1α, HIF-2α, and HIF-3α are transcription factors that regulate the hypoxia-responsive genes. The HIF-α proteins are continuously degraded by an oxygen-dependent degrading pathway involving HIF-prolyl hydroxylases (HIF-PHs) and von Hippel-Lindau tumor suppressor protein. However, upon hypoxia, this degradation ceases and the HIF-α proteins form heterodimers with HIF-1β (a constitutive subunit of HIF), which results in the induction of hypoxia responsive genes. HIF-1α and HIF-2α are potential therapeutic targets for renal anemia, where EPO production is impaired due to chronic kidney diseases. Small molecule HIF-PH inhibitors are currently used to activate HIF-α signaling and to increase plasma hemoglobin levels by restoring EPO production. In this review, we will discuss the current understanding of the roles of the HIF-α signaling pathway in cardiovascular diseases. This will include the roles of HIF-1α in cardiomyocytes as well as in stromal cells including macrophages.

Overall Adverse Event Profile of Vadadustat versus Darbepoetin Alfa for the Treatment of Anemia Associated with Chronic Kidney Disease in Phase 3 Trials

INTRODUCTION

Anemia frequently occurs in chronic kidney disease (CKD), is associated with poor quality of life and cardiovascular outcomes, and its treatment represents a considerable economic burden to the healthcare system. Although effective, the current standard of care for the treatment of anemia in chronic kidney disease patients with erythropoiesis-stimulating agents requires chronic/ongoing injections, making the treatment less accessible or desirable to patients not treated by in-center maintenance hemodialysis. Furthermore, safety concerns, including an increased risk of cardiovascular events and mortality, have emerged from their use in studies targeting hemoglobin concentrations in the normal or near-normal range. The orally active hypoxia-inducible factor prolyl hydroxylase inhibitor vadadustat may offer advantages over erythropoiesis-stimulating agents by correcting anemia via pathways activating endogenous erythropoietin production.

METHODS

To comprehensively analyze the safety profile of vadadustat in patients with dialysis-dependent and non-dialysis-dependent CKD-related anemia, we pooled the safety populations from each of the four trials in the phase 3 clinical program (n = 7,373) and compared the risk of treatment-emergent adverse events (TEAEs) for each treatment arm.

RESULTS

In patients randomized to vadadustat versus darbepoetin alfa, rates of TEAEs (88.9% vs. 89.3%), treatment-emergent serious adverse events (58.0% vs. 59.3%), and TEAEs leading to death (16.1% vs. 16.2%) were similar, as were rates of adverse events of special interest, including cardiovascular-, hepatic-, and neoplasm-related adverse events.

DISCUSSION/CONCLUSION

Among patients with CKD-related anemia treated with vadadustat, we observed similar rates of adverse events relative to those treated with darbepoetin alfa.

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.

Development of a health economic model to evaluate the cost-effectiveness of roxadustat in treating anemia associated with non-dialysis-dependent chronic kidney disease

BACKGROUND

Treatment for anemia of chronic kidney disease (CKD) largely consists of erythropoiesis-stimulating agents (ESAs) with iron supplementation. Although ESAs are well-established and efficacious, their use has been associated with considerable economic and humanistic burdens. Roxadustat, an oral medication, is a hypoxia-inducible factor prolyl hydroxylase inhibitor that targets multiple causes of CKD and has a similar efficacy and safety profile to ESAs. The cost-effectiveness of this treatment, however, has yet to be investigated.

OBJECTIVE

The study objective was to develop a health economic model to evaluate the cost-effectiveness of roxadustat compared with ESAs for treating anemia of non-dialysis-dependent (NDD) CKD.

METHODS

A cohort-based model was developed for a hypothetical cohort of 1,000 patients with anemia of NDD CKD, incorporating eight health states, representing the hemoglobin level of each patient. The model was informed by individual patient-level data from the roxadustat global phase 3 clinical trial program. Total and incremental costs as well as quality-adjusted life-years (QALYs) associated with roxadustat versus ESAs were estimated from the perspective of the UK National Health Service. Sensitivity analyses were performed to assess the robustness of the model. Analyses exploring alternative scenarios were also conducted.

RESULTS

On a per-person basis, over 1,000 simulations, roxadustat was found to be on average less costly (-£32) and more effective (+0.01 QALYs) than ESAs, with a dominant incremental cost-effectiveness ratio. The probability of cost-effectiveness at a £20,000 per QALY willingness-to-pay threshold from the UK perspective was 67%.

CONCLUSION

The model developed may be a useful instrument that, alongside expert clinical opinion, can inform clinical and policy decision-making regarding treatment of anemia of NDD CKD. The model highlights the cost-effectiveness of roxadustat, as well as its potential to have a meaningful impact in reducing the burden of anemia of NDD CKD.

Roxadustat improves renal osteodystrophy by dual regulation of bone remodeling

PURPOSE

Renal osteodystrophy (ROD), a component of chronic kidney disease-mineral and bone disorder (CKD-MBD) can lead to bone loss increasing fracture risks in CKD patients. Therefore, it is important to prevent and treat ROD. Activation of hypoxia-inducible factor-1α (HIF-1α) signaling was reported to prevent osteoporotic bone loss. Roxadustat, which is used to treat renal anemia in the clinic, is a novel HIF stabilizer. In our study, we aimed to investigate the effects of roxadustat on ROD.

METHODS

We established an adenine-induced CKD rat model. Roxadustat was administered intragastrically to normal and CKD rats for 4 weeks. Hemoglobin concentrations and serum biochemical parameters were tested, and bone histomorphometric analysis was performed.

RESULTS

CKD rats exhibited impaired renal function with anemia, secondary hyperparathyroidism and high-turnover ROD-induced significant bone loss. Roxadustat ameliorated renal anemia and attenuated the extreme increase in intact parathyroid hormone (iPTH) and fibroblast growth factor 23 (FGF23) in CKD rats. Bone histomorphometric analysis showed that roxadustat significantly alleviated bone loss and bone microarchitecture deterioration in CKD rats by increasing osteoblast activity and inhibiting osteoclast activity. We did not find that roxadustat had significant effects on bone metabolism in normal rats.

CONCLUSION

Roxadustat can improve ROD via dual regulation of bone remodeling. The use of roxadustat may be a promising strategy to treat osteoporotic bone disorders, such as ROD.

Safety of daprodustat in patients with anemia of chronic kidney disease: A pooled analysis of phase 3 studies in Japan

INTRODUCTION

Daprodustat is an approved treatment for anemia of chronic kidney disease (CKD) in Japan.

METHODS

This post hoc analysis evaluated pooled safety data for daprodustat from 3 phase 3 Japanese studies in dialysis-dependent and nondialysis patients with anemia of CKD.

RESULTS

Median drug exposure duration was 365 days for both daprodustat (N = 369) and injectable erythropoiesis-stimulating agent (ESA, N = 285). The incidence per 100 patient-years of on-therapy adverse events (AEs) was 363.1 and 306.4 in the daprodustat and ESA groups, respectively. The incidence per 100 patient-years of thromboembolic and retinal events were 5.55 and 6.91 (daprodustat) and 6.28 and 7.46 (ESA), respectively. Cardiovascular and malignancy events were similar between groups, although analysis of these were limited by sample size and study duration.

CONCLUSION

The safety of daprodustat was comparable to ESA in this pooled analysis, although further large-scale research is needed to evaluate long-term risks including cardiovascular and malignancy events.

The hypoxia-inducible factor-α prolyl hydroxylase inhibitor FG4592 ameliorates renal fibrosis by inducing the H3K9 demethylase JMJD1A

The transcription factors hypoxia-inducible factor-1α and -2α (HIF-1α/2α) are the major regulators of the cellular response to hypoxia and play a key role in renal fibrosis associated with acute and chronic kidney disease. Jumonji domain-containing 1a (JMJD1A), a histone H3 lysine 9 (H3K9) demethylase, is reported to be an important target gene of HIF-α. However, whether JMJD1A and H3K9 methylation status play a role in renal fibrosis is unclear. Here, we investigated the involvement of HIF-α, JMJD1A, and monomethylated/dimethylated H3K9 (H3K9me1/H3K9me2) levels in unilateral ureteral obstruction (UUO)-induced renal fibrosis in mice. Intraperitoneal administration of FG4592, an inhibitor of HIF-α prolyl hydroxylase, which controls HIF-α protein stability, significantly attenuated renal fibrosis on days 3 and 7 following UUO. FG4592 concomitantly increased JMJD1A expression, decreased H3K9me1/me2 levels, reduced profibrotic gene expression, and increased erythropoietin expression in renal tissues of UUO mice. The beneficial effects of FG4592 on renal fibrosis were inhibited by the administration of JMJD1A-specific siRNA to mice immediately following UUO. Incubation of normal rat kidney-49F and/or -52E cells with transforming growth factor-β1 (TGF-β1) in vitro resulted in upregulated expression of α-smooth muscle actin and H3K9me1/me2, and these effects were inhibited by cotreatment with FG4592. In contrast, FG4592 treatment further enhanced the TGF-β1-stimulated upregulation of JMJD1A but had no effect on TGF-β1-stimulated expression of the H3K9 methyltransferase euchromatic histone-lysine N-methyltransferase 2. Collectively, these findings establish a crucial role for the HIF-α1/2-JMJD1A-H3K9me1/me2 regulatory axis in the therapeutic effect of FG4592 in renal fibrosis.NEW & NOTEWORTHY Using a mouse model of renal fibrosis and transforming growth factor-β1-stimulated rat cell lines, we show that treatment with FG4592, an inhibitor of hypoxia-inducible factor-1α and -2α (HIF-1α/2α) prolyl hydroxylase decreases renal fibrosis and concomitantly reduces methylated lysine 9 of histone H3 (H3K9) levels via upregulation of Jumonji domain-containing 1a (JMJD1A). The results identify a novel role for the HIF-1α/2α-JMJD1A-H3K9 regulatory axis in suppressing renal fibrosis.

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.

Hypoxia-Inducible Factor-Prolyl Hydroxyl Domain Inhibitors: From Theoretical Superiority to Clinical Noninferiority Compared with Current ESAs?

Anemia is a common complication of chronic kidney disease; it is mainly treated with erythropoiesis-stimulating agents (ESAs) and iron. Experimental studies extensively investigated the mechanisms involved in the body's response to hypoxia and led to the discovery of the hypoxia-inducible factor (HIF) pathway and the enzymes regulating its function. HIF-prolyl-hydroxyl domain (PHD) inhibitors are a new class of oral drugs developed to treat anemia in chronic kidney disease. By inhibiting the function of PHD enzymes, they mimic the exposure to moderate hypoxia and stimulate the production of endogenous erythropoietin and very likely increase iron availability. Some data also suggest that their efficacy and, consequently, dose needs are less influenced by inflammation than ESAs. Overall, data from phases 2 and 3 clinical development showed efficacy in anemia correction and maintenance for all of the class molecules compared with placebo (superiority) or erythropoiesis-stimulating agents (noninferiority). Three molecules, roxadustat, vadadustat, and daprodustat, underwent extensive clinical investigation to assess their safety on hard cardiovascular end points, mortality, and special interest events (including cancer and thrombosis). Aside from vadadustat in the nondialysis population, at the prespecified primary analyses, all three molecules met the noninferiority margin for the risk of major cardiovascular events compared with erythropoiesis-stimulating agents or placebo. The reason for this discrepancy is difficult to explain. Other safety signals came from secondary analyses of some of the other randomized clinical trials, including a higher incidence of thrombosis. A more extensive clinical experience with post-marketing data on hard safety issues is needed to define better when and how to use HIF-PHD inhibitors compared with already available ESAs.

Preclinical Characterization of Vadadustat (AKB-6548), an Oral Small Molecule Hypoxia-Inducible Factor Prolyl-4-Hydroxylase Inhibitor, for the Potential Treatment of Renal Anemia

Pharmacological inhibition of prolyl-4-hydroxylase domain (PHD) enzymes stabilizes hypoxia-inducible factors (HIFs), transcription factors that activate target genes that, among others, increase erythropoietin (EPO) synthesis, resulting in the production of new red blood cells (RBCs). Herein, we summarize the preclinical characteristics of the small molecule HIF prolyl-4-hydroxylase inhibitor vadadustat (AKB-6548), which is in development for the treatment of anemia in patients with chronic kidney disease (CKD). Vadadustat inhibits the enzyme activity of all three human PHD isozymes, PHD1, PHD2, and PHD3, with similar low nanomolar inhibitory constant values. PHD enzyme inhibition by vadadustat is competitive with endogenous cofactor 2-oxoglutarate and is insensitive to free iron concentration. In the human hepatocellular carcinoma cell line (Hep 3B) and human umbilical vein endothelial cells, PHD inhibition by vadadustat leads to the time- and concentration-dependent stabilization of HIF-1α and HIF-2α In Hep 3B cells, this in turn results in the synthesis and secretion of EPO; vascular endothelial growth factor is not measured at detectable levels. A single oral dose of vadadustat in rats potently increases circulating levels of EPO, and daily oral dosing for 14 days increases RBC indices in healthy rats and in the 5/6 nephrectomy model of CKD. In mice and dogs, once-daily repeat oral dosing increases hemoglobin and hematocrit. Vadadustat has a relatively short half-life in all nonclinical species evaluated and does not accumulate when administered as a single bolus dose (oral or intravenous) or upon repeat oral dosing. The pharmacological profile of vadadustat supports continued development for treatment of renal anemia. SIGNIFICANCE STATEMENT: Vadadustat (AKB-6548) is an orally bioavailable small molecule prolyl-4-hydroxylase inhibitor in development for anemia of chronic kidney disease. It is an equipotent inhibitor of the three human prolyl-4-hydroxylase domain isoforms, which activates erythropoiesis through stabilization of hypoxia-inducible factor (HIF)-1α and HIF-2α, increasing production of erythropoietin, without detectable stimulation of vascular endothelial growth factor.

Roxadustat regulates iron metabolism in dialysis-dependent and non-dialysis-dependent chronic kidney disease patients: A meta-analysis

BACKGROUND/PURPOSE

The effect of roxadustat on iron homeostasis in patients with chronic kidney disease (CKD) is unclear. This study aimed to evaluate the efficacy of roxadustat for the treatment of iron metabolism disorders in dialysis-dependent (DD) and non-dialysis-dependent (NDD) CKD patients.

METHODS

We searched the PubMed, Embase, China National Knowledge Internet and Web of Science databases for randomized controlled trials (RCTs). The primary outcomes were changes in serum iron, total iron binding capacity (TIBC), transferrin saturation (TSAT), ferritin, transferrin, and hepcidin. The secondary outcomes included the changes in hemoglobin (Hb) and the incidences of adverse events (AEs) and severe adverse events (SAEs).

RESULTS

Twelve RCTs comprising 4976 participants were included. Compared to the control group, increases in the serum iron (SMD = 0.21, 95% CI: 0.15 to 0.27, P < 0.00001), TIBC (SMD = 1.02, 95% CI: 0.82 to 1.22, P < 0.00001) and transferrin levels (WMD = 0.55, 95% CI: 0.41 to 0.69, P < 0.00001) were found in the roxadustat group. Compared to the control group, decreases in the ferritin levels (WMD = -37.82, 95% CI: -59.89 to -15.74, P = 0.0008) and hepcidin levels (WMD = -24.04, 95% CI: -36.28 to -11.79, P = 0.0001) were observed in the roxadustat group. The meta-analysis showed that roxadustat significantly increases Hb levels (WMD = 0.77, 95% CI: 0.42 to 1.12, P < 0.0001). The incidences of AEs and SAEs in the roxadustat group was significantly higher than that in the control group (RR = 1.03, 95% CI: 1.00 to 1.07, P = 0.04; RR = 1.08, 95% CI: 1.00 to 1.15, P = 0.04).

CONCLUSION

Our findings suggest that roxadustat could effectively improve iron metabolism in patients with CKD.

Roxadustat promotes osteoblast differentiation and prevents estrogen deficiency-induced bone loss by stabilizing HIF-1α and activating the Wnt/β-catenin signaling pathway

Background

Osteoporosis is a very common skeletal disorder that increases the risk of fractures. However, the treatment of osteoporosis is challenging. Hypoxia-inducible factor-1α (HIF-1α) plays an important role in bone metabolism. Roxadustat is a novel HIF stabilizer, and its effects on bone metabolism remain unknown. This study aimed to investigate the effects of roxadustat on osteoblast differentiation and bone remodeling in an ovariectomized (OVX) rat model.

Methods

In vitro, primary mouse calvarial osteoblasts were treated with roxadustat. Alkaline phosphatase (ALP) activity and extracellular matrix mineralization were assessed. The mRNA and protein expression levels of osteogenic markers were detected. The effects of roxadustat on the HIF-1α and Wnt/β-catenin pathways were evaluated. Furthermore, osteoblast differentiation was assessed again after HIF-1α expression knockdown or inhibition of the Wnt/β-catenin pathway. In vivo, roxadustat was administered orally to OVX rats for 12 weeks. Then, bone histomorphometric analysis was performed. The protein expression levels of the osteogenic markers HIF-1α and β-catenin in bone tissue were detected.

Results

In vitro, roxadustat significantly increased ALP staining intensity, enhanced matrix mineralization and upregulated the expression of osteogenic markers at the mRNA and protein levels in osteoblasts compared with the control group. Roxadustat activated the HIF-1α and Wnt/β-catenin pathways. HIF-1α knockdown or Wnt/β-catenin pathway inhibition significantly attenuated roxadustat-promoted osteoblast differentiation. In vivo, roxadustat administration improved bone microarchitecture deterioration and alleviated bone loss in OVX rats by promoting bone formation and inhibiting bone resorption. Roxadustat upregulated the protein expression levels of the osteogenic markers, HIF-1α and β-catenin in the bone tissue of OVX rats.

Conclusion

Roxadustat promoted osteoblast differentiation and prevented bone loss in OVX rats. The use of roxadustat may be a new promising strategy to treat osteoporosis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-022-03162-w.

New Approaches to Diabetic Nephropathy from Bed to Bench

Diabetic nephropathy (DN) is the main cause of end-stage kidney disease (ESKD). DN-related ESKD has the worst prognosis for survival compared with other causes. Due to the complex mechanisms of DN and the heterogeneous presentations, unmet needs exist for the renal outcome of diabetes mellitus. Clinical evidence for treating DN is rather solid. For example, the first Kidney Disease: Improving Global Outcomes (KDIGO) guideline was published in October 2020: KDIGO Clinical Practice Guideline for Diabetes Management in Chronic Kidney Disease. In December of 2020, the International Society of Nephrology published 60 (+1) breakthrough discoveries in nephrology. Among these breakthroughs, four important ones after 1980 were recognized, including glomerular hyperfiltration theory, renal protection by renin-angiotensin system inhibition, hypoxia-inducible factor, and sodium-glucose cotransporter 2 inhibitors. Here, we present a review on the pivotal and new mechanisms of DN from the implications of clinical studies and medications.

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.

Roxadustat for the treatment of anemia in patients with lower-risk myelodysplastic syndrome: Open-label, dose-selection, lead-in stage of a phase 3 study

Anemia is the predominant cytopenia in myelodysplastic syndromes (MDS) and treatment options are limited. Roxadustat is a hypoxia-inducible factor prolyl hydroxylase inhibitor approved for the treatment of anemia of chronic kidney disease in the UK, EU, China, Japan, South Korea, and Chile. MATTERHORN is a phase 3, randomized, double-blind, placebo-controlled study to assess the efficacy and safety of roxadustat in anemia of lower risk-MDS. Eligible patients had baseline serum erythropoietin ≤ 400 mIU/mL, and a low packed RBC transfusion burden. In this open-label (OL), dose-selection, lead-in phase, enrolled patients were assigned to 1 of 3 roxadustat starting doses (n = 8 each): 1.5, 2.0, and 2.5 mg/kg. The primary efficacy endpoint of the OL phase was the proportion of patients with transfusion independence (TI) for ≥ 8 consecutive weeks in the first 28 treatment weeks. A secondary efficacy endpoint was the proportion of patients with a ≥ 50% reduction in RBC transfusions over an 8-week period compared with baseline. Adverse events were monitored. Patients were followed for 52 weeks. Of the 24 treated patients, TI was achieved in 9 patients (37.5%) at 28 and 52 weeks; 7 of these patients were receiving 2.5 mg/kg dose when TI was achieved. A ≥ 50% reduction in RBC transfusions was achieved in 54.2% and 58.3% of patients at 28 and 52 weeks, respectively. Oral roxadustat dosed thrice weekly was well tolerated. There were no fatalities or progression to acute myeloid leukemia. Based on these outcomes, 2.5 mg/kg was the chosen starting roxadustat dose for the ongoing double-blind study phase.

Molecular mechanisms underlying the role of hypoxia-inducible factor-1 α in metabolic reprogramming in renal fibrosis

Renal fibrosis is the result of renal tissue damage and repair response disorders. If fibrosis is not effectively blocked, it causes loss of renal function, leading to chronic renal failure. Metabolic reprogramming, which promotes cell proliferation by regulating cellular energy metabolism, is considered a unique tumor cell marker. The transition from oxidative phosphorylation to aerobic glycolysis is a major feature of renal fibrosis. Hypoxia-inducible factor-1 α (HIF-1α), a vital transcription factor, senses oxygen status, induces adaptive changes in cell metabolism, and plays an important role in renal fibrosis and glucose metabolism. This review focuses on the regulation of proteins related to aerobic glycolysis by HIF-1α and attempts to elucidate the possible regulatory mechanism underlying the effects of HIF-1α on glucose metabolism during renal fibrosis, aiming to provide new ideas for targeted metabolic pathway intervention in renal fibrosis.

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.