Phase 3, Randomized, Double-Blind, Active-Comparator (Darbepoetin Alfa) Study of Oral Roxadustat in CKD Patients with Anemia on Hemodialysis in Japan

Roxadustat treatment for anemia in peritoneal dialysis patients: A randomized controlled trial

BACKGROUND/PURPOSE

Roxadustat, a first-in-class hypoxia-inducible factor prolyl hydroxylase inhibitor, promotes erythropoiesis and regulates iron metabolism. This study investigated the efficacy and safety of roxadustat in Chinese patients with anemia on peritoneal dialysis (PD).

METHODS

One hundred and twenty-nine patients were randomized and treated with roxadustat (n = 86) or erythropoiesis-stimulating agents (ESAs) (n = 43) for 24 weeks. The primary end points were the mean hemoglobin (Hb) level at week 24, the change in average Hb levels from baseline to week 24, and the cumulative response rate throughout the treatment period. The secondary end points included changes in hepcidin and iron indices and serum lipid levels. Subgroup analysis examined the effect of inflammatory status on the efficacy of Hb. Safety was assessed as the occurrence of emergent adverse events after treatment.

RESULTS

The mean average Hb levels at week 24 and average change in Hb levels from baseline to week 24 were 11.5 g/dL and 2.5 g/dL in the roxadustat group and 11.2 g/dL and 2.2 g/dL in the ESAs group, respectively. The cumulative response rate was 96% in the roxadustat group and 92% in the ESAs group at week 24. Roxadustat decreased hepcidin levels and increased total iron-binding capacity. The decreases in total cholesterol and low-density lipoprotein cholesterol were greater with roxadustat than with ESAs. Roxadustat-induced Hb increases were independent of baseline C-reactive protein levels. Common adverse events included hyperkalemia, hypertension, and insomnia.

CONCLUSION

Roxadustat effectively corrected and maintained target Hb levels in Chinese PD patients. This trial was registered in the Chinese Clinical Trial Register (ChiCTR2000035054).

Hypoxia-inducible factor prolyl hydroxylase domain inhibitor may maintain hemoglobin synthesis at lower serum ferritin and transferrin saturation levels than darbepoetin alfa

Background

Hypoxia-inducible factor (HIF) prolyl hydroxylase domain inhibitors, which have recently become clinically available for treating renal anemia, are attracting attention for their novel mechanisms of action.

Methods

Relationships of reticulocyte hemoglobin content (CHr), which reflects recent Hb synthesis, with serum ferritin (s-ft) and transferrin saturation (TSAT) were examined in 30 patients on hemodialysis after switching from darbepoetin alfa (DA) to roxadustat (Rox). Iron deficiency was defined as CHr < 32.0 pg. Cutoff values of s-ft and TSAT were determined using receiver operating characteristic curves for the endpoint CHr ≥ 32.0 pg. Logistic analysis was performed with the reference group having s-ft or TSAT below the corresponding cutoff value (low vs high).

Results

With the endpoint CHr ≥ 32.0 pg on Day 0, cutoff values for s-ft and TSAT were respectively 49.7 ng/mL and 21.6% on Day 0 and 35.5 ng/mL and 16.2% on Day 28. With the endpoint CHr ≥ 32.0 pg on Day 28, cutoff values for s-ft and TSAT on Day 0 were 81.6 ng/mL and 23.9%, respectively. According to multivariable logistic analysis, the odds ratios of CHr ≥ 32.0 pg on Day 0 were significantly higher for high TSAT on Day 0 [34.7 (95% CI 2.42–131.0), p<0.003] and Day 28 [24.8 (95% CI 2.75–224.0), p = 0.004]. There were no significant differences by s-ft. Odd ratios of CHr ≥ 32.0 pg on Day 28 were also significantly higher for high s-ft on Day 0 [16.0 (95% CI 1.57–163.0), p = 0.019] and high TSAT on Day 0 [13.5 (95% CI 1.24–147.0), p<0.033].

Conclusions

Our results suggest Hb synthesis was maintained with lower TSAT and s-ft during Rox therapy compared with DA therapy. To avoid iron deficiency during the 4 weeks after switching DA to Rox, ideal s-ft and TSAT levels before the switch are 81.6 ng/mL and 23.9%, respectively.

Roxadustat for the treatment of anaemia in chronic kidney disease patients not on dialysis: a phase 3, randomised, open-label, active-controlled study (DOLOMITES)

Background

Roxadustat, an orally administered hypoxia-inducible factor prolyl hydroxylase inhibitor, is being evaluated for treatment of anaemia of chronic kidney disease (CKD).

Methods

This randomized, open-label, active-controlled Phase 3 study compared roxadustat versus darbepoetin alfa (DA) in non-dialysis-dependent (NDD) CKD patients with anaemia for ≤104 weeks. Doses were titrated to correct and maintain haemoglobin (Hb) within 10.0–12.0 g/dL. The primary endpoint was Hb response in the full analysis set, defined as Hb ≥11.0 g/dL and Hb change from baseline (BL; CFB) ≥1.0 g/dL in patients with BL Hb >8.0 g/dL or CFB ≥2.0 g/dL in patients with BL Hb ≤8.0 g/dL during the first 24 weeks of treatment without rescue therapy (non-inferiority margin, −15%). Key secondary endpoints included change in low-density lipoprotein (LDL), time to first intravenous (IV) iron use, change in mean arterial pressure (MAP) and time to hypertension occurrence. Adverse events were assessed.

Results

Of 616 randomized patients (roxadustat, 323; DA, 293), 424 completed treatment (roxadustat, 215; DA, 209). Hb response with roxadustat was non-inferior to DA (roxadustat: 256/286, 89.5% versus DA: 213/273, 78.0%, difference 11.51%, 95% confidence interval 5.66–17.36%). Roxadustat maintained Hb for up to 2 years. Roxadustat was non-inferior to DA for change in MAP and time to occurrence of hypertension and superior for change in LDL and time to first IV iron use. Safety profiles were comparable between groups. Findings suggest that there was no difference between groups regarding the composite endpoints major adverse cardiovascular events (MACEs) and MACE+ [MACE: 0.81 (0.52–1.25), P = 0.339; MACE+: 0.90 (0.61–1.32), P = 0.583].

Conclusions

Roxadustat is a viable option to treat anaemia in NDD CKD patients maintaining Hb levels for up to 104 weeks.

Controversies in optimal anemia management: conclusions from a Kidney Disease: Improving Global Outcomes (KDIGO) Conference

In chronic kidney disease, anemia and disordered iron homeostasis are prevalent and associated with significant adverse consequences. In 2012, Kidney Disease: Improving Global Outcomes (KDIGO) issued an anemia guideline for managing the diagnosis, evaluation, and treatment of anemia in chronic kidney disease. Since then, new data have accrued from basic research, epidemiological studies, and randomized trials that warrant a re-examination of previous recommendations. Therefore, in 2019, KDIGO decided to convene 2 Controversies Conferences to review the latest evidence, explore new and ongoing controversies, assess change implications for the current KDIGO anemia guideline, and propose a research agenda. The first conference, described here, focused mainly on iron-related issues, including the contribution of disordered iron homeostasis to the anemia of chronic kidney disease, diagnostic challenges, available and emerging iron therapies, treatment targets, and patient outcomes. The second conference will discuss issues more specifically related to erythropoiesis-stimulating agents, including epoetins, and hypoxia-inducible factor-prolyl hydroxylase inhibitors. Here we provide a concise overview of the consensus points and controversies resulting from the first conference and prioritize key questions that need to be answered by future research.

Physiological and pathophysiological mechanisms of hepcidin regulation: clinical implications for iron disorders

The discovery of hepcidin has provided a solid foundation for understanding the mechanisms of systemic iron homeostasis and the aetiologies of iron disorders. Hepcidin assures the balance of circulating and stored iron levels for multiple physiological processes including oxygen transport and erythropoiesis, while limiting the toxicity of excess iron. The liver is the major site where regulatory signals from iron, erythropoietic drive and inflammation are integrated to control hepcidin production. Pathologically, hepcidin dysregulation by genetic inactivation, ineffective erythropoiesis, or inflammation leads to diseases of iron deficiency or overload such as iron-refractory iron-deficiency anaemia, anaemia of inflammation, iron-loading anaemias and hereditary haemochromatosis. In the present review, we discuss recent insights into the molecular mechanisms governing hepcidin regulation, how these pathways are disrupted in iron disorders, and how this knowledge is being used to develop novel diagnostic and therapeutic strategies.

Roxadustat as treatment for a blood transfusion-dependent maintenance hemodialysis patient: A case report and review of literature

BACKGROUND

Erythropoiesis-stimulating agents (ESAs) have revolutionized the therapeutic strategy for anemia in chronic kidney disease. However, some cases are resistant or hyporesponsive to ESAs. Roxadustat is an oral hypoxia-inducible factor-prolyl hydroxylase inhibitor that stimulates erythropoiesis and regulates iron metabolism. Here, we describe a hemodialysis patient with refractory anemia who did not respond to traditional treatments and depended on blood transfusion for more than 1 year. After applying Roxadustat, the patient’s anemia improved significantly.

CASE SUMMARY

A 44-year-old man was diagnosed with uremia accompanied by severe anemia with a hemoglobin (Hb) level ranging from 30-40 g/L. His anemia did not improve after sufficient dialysis or high doses of active ESAs; other causes of anemia were excluded. The patient required approximately 600-1000 mL of red blood cell suspension every 15-30 d for more than 1 year. After accepting Roxadustat therapy, the patient’s anemia symptoms improved significantly; his Hb level gradually increased to 50 g/L, and no further blood transfusions were administered. His Hb level reached 69 g/L by the 34^th week. Although a Hb level of 60-70 g/L cannot be considered satisfactory, he no longer required blood transfusions and his quality of life was substantially improved. Roxadustat showed good efficacy and safety in this case.

CONCLUSION

Roxadustat represents an innovative and effective agent for the clinical treatment of renal anemia caused by multiple complex factors.

[Roxadustat (Evrenzo® tablet), a therapeutic drug for renal anemia: pharmacological characteristics and clinical evidence in Japan]

Roxadustat (Evrenzo^® tablet) is an oral hypoxia-inducible factor prolyl hydroxylase (HIF-PH) inhibitor. Roxadustat has been approved for the treatment of renal anemia in patients on dialysis in September 2019 in Japan. By inhibiting HIF-PH, roxadustat suppresses the degradation of HIF-α, a subunit of the heterodimeric transcription factor HIF, leading to its accumulation and activation of the HIF pathway. Similar to activation of the HIF pathway in response to hypoxia, the production of endogenous erythropoietin is increased and erythropoiesis is stimulated. Moreover, roxadustat stimulates erythropoiesis efficiently by improving iron bioavailability. The efficacy and mechanism of action of roxadustat have been detailed in non-clinical pharmacology studies. Rat models of anemia demonstrated efficacy of roxadustat in correcting anemia and changes in gene expression leading to increased iron bioavailability. Four phase 3 clinical studies in Japan clearly demonstrated the efficacy of roxadustat in patients with renal anemia on dialysis. Roxadustat showed an acceptable safety profile, and the incidences and types of adverse events and serious adverse events reported in the clinical studies were similar with those predicted to occur in these patient population. Since roxadustat is an oral drug, concerns present with erythropoiesis-stimulating agents (ESAs) such as the risk of infection to the medical staff due to accidental needle-stick, pain during ESA injection in patients and burden on patients to visit a hospital, can be avoided or reduced. In November 2020, roxadustat has also been approved for the treatment of renal anemia in patients not on dialysis (data not shown in this article).

Effect of the Phosphate Binders Sevelamer Carbonate and Calcium Acetate on the Pharmacokinetics of Roxadustat After Concomitant or Time-Separated Administration in Healthy Individuals

PURPOSE

Roxadustat, a hypoxia-inducible factor prolyl hydroxylase inhibitor, treats anemia in chronic kidney disease. Hyperphosphatemia, a common complication in chronic kidney disease, is treated with phosphate binders (PBs). This study in healthy individuals investigated the effect of 2 PBs, sevelamer carbonate and calcium acetate, on the pharmacokinetic properties of a single oral dose of roxadustat administered concomitantly or with a time lag.

METHODS

This 2-part, Phase I study was conducted with an open-label, randomized, 3-way (part 1) or 5-way (part 2) crossover design, with 5-day treatment periods. On day 1 of each period, participants received 200 mg roxadustat administered alone or (1) concomitantly with sevelamer carbonate (2400 mg) or calcium acetate (1900 mg) (part 1) or (2) 1 hour before or 1, 2, or 3 hours after sevelamer carbonate (part 2A) or calcium acetate (part 2B); 5 additional PB doses were administered during 2 days. In both parts, PBs were administered with meals. Primary pharmacokinetic variables were AUC_0-∞ and C_max. FINDINGS: Twenty-four individuals were randomized in part 1; 60 individuals were randomized in part 2 (part 2A, n = 30; part 2B, n = 30). All participants completed the study in part 1; 28 and 27 individuals completed the study in part 2A and part 2B, respectively. Compared with roxadustat alone, concomitant sevelamer carbonate and calcium acetate administration reduced roxadustat's AUC_0-∞ by 67% (90% CI, 63.5%-69.3%) and 46% (90% CI, 41.7%-50.9%), respectively, and reduced roxadustat's C_max by 66% (90% CI, 61.6%-69.4%) and 52% (90% CI, 46.2%-57.2%), respectively. This effect was attenuated when roxadustat and PB administration occurred with a time lag. Roxadustat's AUC_0-∞ was reduced by 41% and 22% to 25%, respectively, when roxadustat was administered 1 hour before or 1 to 3 hours after sevelamer carbonate and by 31% and 14% to 18%, respectively, when administered 1 hour before or 1 to 3 hours after calcium acetate. Roxadustat's C_max was reduced by 26% and 12%, respectively, when roxadustat was administered 1 hour before and 1 hour after sevelamer carbonate; it was reduced by 19% when administered 1 hour before calcium acetate and was not affected when administered 1 hour after. Roxadustat was well tolerated.

IMPLICATIONS

Concomitant administration of roxadustat with sevelamer carbonate or calcium acetate reduced exposure to roxadustat in healthy individuals. This effect was attenuated when roxadustat was administered ≥1 hour before or after either PB. Results from this study helped inform dosing and administration guidelines aimed at reducing interactions between roxadustat and these PBs. (Clin Ther. 2021;XX:XXX-XXX) © 2021 Elsevier HS Journals, Inc.

Anemia Management in Peritoneal Dialysis: Perspectives From the Asia Pacific Region

Anemia is an important complication in patients with chronic kidney disease. Peritoneal dialysis (PD) is one of the most common modalities of kidney replacement therapy for patients with end-stage kidney disease. PD is particularly prevalent in the Asian Pacific region. Among the different countries and regions, including mainland China, Hong Kong, Japan, Malaysia, Singapore, South Korea, and Thailand, PD accounts for 2.8% to 74.6% of the dialysis population. In addition, 82% to 96% of the PD populations from these countries and regions are receiving erythropoiesis-stimulating agents (ESAs). Asian Pacific countries and regions follow the latest KDIGO (Kidney Disease: Improving Global Outcomes) guidelines for the initiation of treatment of anemia in PD patients. The types of ESAs commonly used include shorter-acting (epoetin alfa and beta) and longer-acting agents, including darbepoetin alfa or methoxy polyethylene glycol-epoetin beta. The most commonly used ESAs in Mainland China, Malaysia, Singapore, and Thailand are the shorter-acting agents, whereas in Hong Kong, Japan, and South Korea, longer-acting ESAs are most common. Oral iron therapy is still the most commonly used iron supplement. The route and dosage of iron administration in PD patients requires more research studies. With the introduction of oral hypoxia-inducible factor prolyl hydroxylase inhibitors into clinical use, the landscape of treatment of anemia in the PD population in the Asia Pacific region may change in the coming years.

HIF-α Prolyl Hydroxylase Inhibitors and Their Implications for Biomedicine: A Comprehensive Review

Oxygen is essential for the maintenance of the body. Living organisms have evolved systems to secure an oxygen environment to be proper. Hypoxia-inducible factor (HIF) plays an essential role in this process; it is a transcription factor that mediates erythropoietin (EPO) induction at the transcriptional level under hypoxic environment. After successful cDNA cloning in 1995, a line of studies were conducted for elucidating the molecular mechanism of HIF activation in response to hypoxia. In 2001, cDNA cloning of dioxygenases acting on prolines and asparagine residues, which play essential roles in this process, was reported. HIF-prolyl hydroxylases (PHs) are molecules that constitute the core molecular mechanism of detecting a decrease in the partial pressure of oxygen, or hypoxia, in the cells; they can be called oxygen sensors. In this review, I discuss the process of molecular cloning of HIF and HIF-PH, which explains hypoxia-induced EPO expression; the development of HIF-PH inhibitors that artificially or exogenously activate HIF by inhibiting HIF-PH; and the significance and implications of medical intervention using HIF-PH inhibitors.

Hypoxic and pharmacological activation of HIF inhibits SARS-CoV-2 infection of lung epithelial cells

COVID-19, caused by the novel coronavirus SARS-CoV-2, is a global health issue with more than 2 million fatalities to date. Viral replication is shaped by the cellular microenvironment, and one important factor to consider is oxygen tension, in which hypoxia inducible factor (HIF) regulates transcriptional responses to hypoxia. SARS-CoV-2 primarily infects cells of the respiratory tract, entering via its spike glycoprotein binding to angiotensin-converting enzyme 2 (ACE2). We demonstrate that hypoxia and the HIF prolyl hydroxylase inhibitor Roxadustat reduce ACE2 expression and inhibit SARS-CoV-2 entry and replication in lung epithelial cells via an HIF-1α-dependent pathway. Hypoxia and Roxadustat inhibit SARS-CoV-2 RNA replication, showing that post-entry steps in the viral life cycle are oxygen sensitive. This study highlights the importance of HIF signaling in regulating multiple aspects of SARS-CoV-2 infection and raises the potential use of HIF prolyl hydroxylase inhibitors in the prevention or treatment of COVID-19.

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

Introduction

Roxadustat is an oral hypoxia-inducible factor prolyl hydroxylase inhibitor that has demonstrated safety and efficacy versus placebo in phase III trials in patients with anemia of chronic kidney disease (CKD) who were not on dialysis (NDD).

Methods

This was a phase III, active-controlled, multicenter, partially randomized, open-label study in Japanese patients with NDD CKD. Patients who had used recombinant human erythropoietin or darbepoetin alfa (DA) before conversion were randomized to roxadustat or DA (comparative arms). Patients who had used epoetin beta pegol before conversion were allocated to roxadustat (reference arm). The primary endpoint was change in average hemoglobin (Hb) level from baseline during the evaluation period (Weeks 18–24). Longer term efficacy and safety were evaluated in roxadustat-treated patients over 52 weeks.

Results

In this study, 334 patients were randomized/allocated to receive treatment (n = 132, roxadustat [comparative]; n = 131, DA [comparative]; n = 71, roxadustat [reference]). The estimated difference between the roxadustat (comparative) and DA (comparative) groups in the least squares mean of change of average Hb levels of Weeks 18 to 24 from baseline was –0.07 g/dl, with the lower limit of 95% confidence interval of –0.23 g/dl, thereby confirming the noninferiority of roxadustat to DA. Common treatment-emergent adverse events (≥3% of patients in any treatment group) observed during the 24-week treatment period included nasopharyngitis, CKD, hyperkalemia, and hypertension.

Conclusion

Roxadustat maintained Hb within 10 to 12 g/dl in NDD CKD patients and was noninferior to DA. The safety profiles observed in this study are consistent with previous studies performed in this patient population.

Hypoxia-inducible factor-prolyl hydroxylase inhibitors in the treatment of anemia of chronic kidney disease

Hypoxia-inducible factor-prolyl hydroxylase domain inhibitors (HIF-PHIs) are a promising new class of orally administered drugs currently in late-stage global clinical development for the treatment of anemia of chronic kidney disease (CKD). HIF-PHIs activate the HIF oxygen-sensing pathway and are efficacious in correcting and maintaining hemoglobin levels in patients with non-dialysis- and dialysis-dependent CKD. In addition to promoting erythropoiesis through the increase in endogenous erythropoietin production, HIF-PHIs reduce hepcidin levels and modulate iron metabolism, providing increases in total iron binding capacity and transferrin levels, and potentially reducing the need for i.v. iron supplementation. Furthermore, HIF-activating drugs are predicted to have effects that extend beyond erythropoiesis. This review summarizes clinical data from current HIF-PHI trials in patients with anemia of CKD, discusses mechanisms of action and pharmacologic properties of HIF-PHIs, and deliberates over safety concerns and potential impact on anemia management in patients with CKD.

Anemia in Chronic Kidney Disease: From Pathophysiology and Current Treatments, to Future Agents

Anemia is a common complication in chronic kidney disease (CKD), and is associated with a reduced quality of life, and an increased morbidity and mortality. The mechanisms involved in anemia associated to CKD are diverse and complex. They include a decrease in endogenous erythropoietin (EPO) production, absolute and/or functional iron deficiency, and inflammation with increased hepcidin levels, among others. Patients are most commonly managed with oral or intravenous iron supplements and with erythropoiesis stimulating agents (ESA). However, these treatments have associated risks, and sometimes are insufficiently effective. Nonetheless, in the last years, there have been some remarkable advances in the treatment of CKD-related anemia, which have raised great expectations. On the one hand, a novel family of drugs has been developed: the hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHIs). These agents induce, among other effects, an increase in the production of endogenous EPO, improve iron availability and reduce hepcidin levels. Some of them have already received marketing authorization. On the other hand, recent clinical trials have elucidated important aspects of iron supplementation, which may change the treatment targets in the future. This article reviews the current knowledge of the pathophysiology CKD-related anemia, current and future therapies, the trends in patient management and the unmet goals.

Suppression of thyrotropin secretion during roxadustat treatment for renal anemia in a patient undergoing hemodialysis

Background

Inhibition of hypoxia-inducible factor prolyl hydroxylase (HIF-PH) is a novel choice for the treatment of renal anemia, and an oral HIF-PH inhibitor roxadustat was approved for renal anemia. Roxadustat has high affinity to thyroid hormone receptor beta, which may affect thyroid hormone homeostasis.

Case presentation

We present here a patient undergoing hemodialysis with primary hypothyroidism receiving levothyroxine replacement, who showed decreased free thyroxine (FT4) and thyroid stimulating hormone (TSH) after starting roxadustat. Pituitary stimulation test revealed selective suppression of TSH secretion. Recovery of TSH and FT4 levels after stopping roxadustat suggested the suppression of TSH was reversible.

Conclusions

Physicians should pay special attention to thyroid hormone abnormalities in treatment with roxadustat.

Roxadustat for anemia in patients with end-stage renal disease incident to dialysis

BACKGROUND

We evaluated the efficacy and safety of roxadustat versus epoetin alfa for the treatment of chronic kidney disease-related anemia in patients new to dialysis.

METHODS

HIMALAYAS was a Phase 3, open-label, epoetin alfa-controlled trial. Eligible adults were incident to hemodialysis/peritoneal dialysis for 2 weeks to ≤4 months prior to randomization and had mean hemoglobin (Hb) ≤10.0 g/dL. Primary endpoints were mean Hb (g/dL) change from baseline averaged over Weeks 28-52 regardless of rescue therapy [non-inferiority criterion: lower limit of 95% confidence interval (CI) for treatment difference >-0.75] and percentage of patients achieving an Hb response between Weeks 1 and 24 censored for rescue therapy (non-inferiority margin for between-group difference -15%). Adverse events were monitored.

RESULTS

The intent-to-treat population included patients randomized to roxadustat (n = 522) or epoetin alfa (n = 521). Mean (standard deviation) Hb changes from baseline averaged over Weeks 28-52 were 2.57 (1.27) and 2.36 (1.21) in the roxadustat and epoetin alfa groups. Roxadustat was non-inferior [least squares mean difference: 0.18 (95% CI 0.08, 0.29)] to epoetin alfa. Percentages of patients with an Hb response were 88.2% and 84.4% in the roxadustat and epoetin alfa groups, respectively. Roxadustat was non-inferior to epoetin alfa [treatment-group difference 3.5% (95% CI -0.7%, 7.7%)]. Adverse event rates were comparable between treatment groups.

CONCLUSIONS

Roxadustat was efficacious for correcting and maintaining Hb levels compared with epoetin alfa. Roxadustat had an acceptable safety profile.

Roxadustat for the treatment of anemia in chronic kidney disease patients not on dialysis: a Phase 3, randomized, double-blind, placebo-controlled study (ALPS)

BACKGROUND

Roxadustat is an orally active hypoxia-inducible factor prolyl hydroxylase inhibitor for the treatment of chronic kidney disease (CKD) anemia.

METHODS

This Phase 3, multicenter, randomized, double-blind, placebo-controlled study examined patients with Stages 3-5 CKD, not on dialysis (NCT01887600). Patients were randomized (2:1) to oral roxadustat or placebo three times weekly for 52-104 weeks. This study examined two primary efficacy endpoints: European Union (European Medicines Agency)-hemoglobin (Hb) response, defined as Hb ≥11.0 g/dL that increased from baseline (BL) by ≥1.0 g/dL in patients with Hb >8.0 g/dL or ≥2.0 g/dL in patients with BL Hb ≤8.0 g/dL, without rescue therapy, during the first 24 weeks of treatment; US Food and Drug Administration-change in Hb from BL to the average Hb level during Weeks 28-52, regardless of rescue therapy. Secondary efficacy endpoints and safety were examined.

RESULTS

A total of 594 patients were analyzed (roxadustat: 391; placebo: 203). Superiority of roxadustat versus placebo was demonstrated for both primary efficacy endpoints: Hb response [odds ratio = 34.74, 95% confidence interval (CI) 20.48-58.93] and change in Hb from BL [roxadustat - placebo: +1.692 (95% CI 1.52-1.86); both P < 0.001]. Superiority of roxadustat was demonstrated for low-density lipoprotein cholesterol change from BL, and time to first use of rescue medication (both P < 0.001). The incidences of treatment-emergent adverse events were comparable between groups (roxadustat: 87.7%, placebo: 86.7%).

CONCLUSIONS

Roxadustat demonstrated superior efficacy versus placebo in terms of both Hb response rate and change in Hb from BL. The safety profiles of roxadustat and placebo were comparable.

Long-term efficacy and safety of hypoxia-inducible factor prolyl hydroxylase inhibitors in anaemia of chronic kidney disease: A meta-analysis including 13,146 patients

WHAT IS KNOWN AND OBJECTIVE

Previous studies based on small-sample clinical data proved that short-term use of hypoxia-inducible factor prolyl hydroxylase (HIF-PHD) inhibitors increased haemoglobin levels in anaemic patients with chronic kidney disease (CKD). However, these studies reached conflicting conclusions on iron parameters and adverse event profiles. Our meta-analysis aimed to evaluate the long-term efficacy and safety of HIF-PHD inhibitors in renal anaemia.

METHODS

Randomized controlled trials comparing treatment with HIF-PHD inhibitors versus placebo or erythropoiesis-stimulating agents (ESAs) were thoroughly searched in the PubMed, Embase, Cochrane Library and international clinical trial registries. Meta-analysis was performed on main outcomes with random effects models.

RESULTS AND DISCUSSION

A total of 30 studies comprising 13,146 patients were included. The HIF-PHD inhibitors used included roxadustat, daprodustat, vadadustat, molidustat, desidustat and enarodustat. HIF-PHD inhibitors significantly increased haemoglobin levels in comparison with placebo [weighted mean difference (WMD) 1.53, 95% confidence interval (CI) 1.39 to 1.67] or ESAs (WMD 0.13, 95% CI 0.03 to 0.22). Hepcidin, ferritin and serum iron levels were decreased, while total iron binding capacity and transferrin levels were increased in the HIF-PHD inhibitor group versus those in placebo or ESAs group. Additionally, HIF-PHD inhibitors medication was associated with cholesterol-lowering effects. As for safety, the risk of serious adverse events in the HIF-PHD inhibitor group was increased in comparison with placebo group [risk ratio (RR) 1.07, 95% CI 1.01 to 1.13], but comparable to the ESAs group (RR 1.02, 95% CI 0.94 to 1.10). Compared with placebo, the agents increased the risk of diarrhoea (1.21, 1.00 to 1.47), nausea (1.46, 1.09 to 1.97), oedema peripheral (1.32, 1.01 to 1.59), hyperkalemia (1.27, 1.05 to 1.54) and hypertension (1.34, 1.02 to 1.76). Compared with ESAs, the drugs increased the risk of vomiting (1.30, 1.02 to 1.65), headache (1.27, 1.05 to 1.53) and thrombosis events (1.31, 1.05 to 1.63).

WHAT IS NEW AND CONCLUSION

HIF-PHD inhibitors treatment effectively increased haemoglobin levels and promoted iron utilization in anaemic patients with CKD, and they were well tolerated for long-term use. In order to avoid unfavourable effects of excessive iron consumption, it was appropriate to administer HIF-PHD inhibitors in combination with iron supplements for long-term treatment.

ESA, Iron Therapy and New Drugs: Are There New Perspectives in the Treatment of Anaemia?

Anemia is a well-known consequence of chronic kidney disease (CKD); it is mainly due to a relative insufficiency of erythropoietin synthesis by the failing kidneys. Over the years, the combination of erythropoiesis stimulating agents (ESA) and iron has become the standard of care of anemia. All ESAs effectively increase hemoglobin (Hb) levels in a substantial percentage of patients. However, in the last decade, their use has been surrounded by safety issues in increased cardiovascular risk, especially when used at high doses in inflamed and hyporesponsive patients. This has led to the definition of a more cautious Hb target. Iron deficiency is very frequent in CKD patients, with a higher frequency in non-dialysis patients. Traditionally, iron supplementation is mostly used as supportive therapy for anemia control. However, the concept is growing that intravenous iron therapy per se could be beneficial in the presence of heart failure. A new class of drugs, prolyl hydroxylase domain (PHD) inhibitors (PHD inhibitors) is becoming available for the treatment of anemia in CKD patients. Theoretically, these agents have a number of advantages, the main ones being that of stimulating the synthesis of endogenous erythropoietin and increasing iron availability. The impact of their future use in clinical practice is still to be defined. Another possible strategy could be targeting serum hepcidin and its related pathways. This possibility is fascinating from the scientific point of view, but at present its development phase is still far from clinical application.

Whether Prolyl Hydroxylase Blocker-Roxadustat-In the Treatment of Anemia in Patients with Chronic Kidney Disease Is the Future?

In patients with chronic kidney disease (CKD), anemia develops gradually, which is primarily due to an inadequate synthesis of erythropoietin by the kidneys, as well as to iron disorders in the body, blood loss, shortened erythrocyte survival and inflammation. The currently accepted treatment employs iron, vitamin B12, folic acid supplementation and the use of erythropoiesis stimulants, which are administered only parenterally. Research is currently underway on the new erythropoiesis drugs that can be orally administered, i.e., hypoxia-inducible factor-propyl hydroxylase inhibitor (HIF-PHI) inhibitors which temporarily block propyl hydroxylase [PHD] catalysis and promote a transient increase in the expression of genes regulated by HIF, including kidney and liver erythropoietin [EPO]. Roxadustat is the first oral drug in this class and a potent HIF-PHD inhibitor, exerted to treat anemia in patients with CKD. In phase 1, 2 and 3 studies with CKD-affected patients, roxadustat was more effective to stimulate erythropoiesis for anemia correction than previously used drugs. Roxadustat can be orally given, unlike other erythropoiesis drugs with parenteral administration only, which grants roxadustat a considerable advantage. Our paper presents the results of studies with roxadustat applied for the treatment of anemia in CKD patients with or without dialysis. We are currently not yet able to know the exact role of roxadustat in the treatment of anemia in patients with CKD, but time will tell. It is possible that roxadustat has benefits an iron metabolism and cardiovascular risk.

Iron Therapy in Chronic Kidney Disease: Days of Future Past

Anemia affects millions of patients with chronic kidney disease (CKD) and prompt iron supplementation can lead to reductions in the required dose of erythropoiesis-stimulating agents, thereby reducing medical costs. Oral and intravenous (IV) traditional iron preparations are considered far from ideal, primarily due to gastrointestinal intolerability and the potential risk of infusion reactions, respectively. Fortunately, the emergence of novel iron replacement therapies has engendered a paradigm shift in the treatment of iron deficiency anemia in patients with CKD. For example, oral ferric citrate is an efficacious and safe phosphate binder that increases iron stores to maintain hemoglobin levels. Additional benefits include reductions in fibroblast growth factor 23 levels and the activation of 1,25 dihydroxyvitamin D. The new-generation IV iron preparations ferumoxytol, iron isomaltoside 1000, and ferric carboxymaltose are characterized by a reduced risk of infusion reactions and are clinically well tolerated as a rapid high-dose infusion. In patients undergoing hemodialysis (HD), ferric pyrophosphate citrate (FPC) administered through dialysate enables the replacement of ongoing uremic and HD-related iron loss. FPC transports iron directly to transferrin, bypassing the reticuloendothelial system and avoiding iron sequestration. Moreover, this paper summarizes recent advancements of hypoxia-inducible factor prolyl hydroxylase inhibitors and future perspectives in renal anemia management.

Factors affecting the doses of roxadustat vs darbepoetin alfa for anemia treatment in hemodialysis patients

Roxadustat is an oral hypoxia‐inducible factor prolyl hydroxylase inhibitor for the treatment of anemia in chronic kidney disease (CKD). Emerging evidence suggests that roxadustat may be beneficial for patients who inadequately respond to erythropoiesis‐stimulating agents (ESAs). This post‐hoc analysis of a Japanese, double‐blind, randomized, phase 3 study in hemodialysis‐dependent CKD patients treated with traditional ESAs assessed the impact of factors associated with ESA hyporesponsiveness on roxadustat and darbepoetin alfa (DA) doses required to maintain target hemoglobin. Endpoints included mean of average doses of roxadustat and DA per administration in the last 6 weeks (AAD/6W) by prior ESA‐resistance index (ERI), iron repletion (transferrin saturation; ferritin), and high‐sensitivity C‐reactive protein (hs‐CRP). Of 415 enrolled patients, 303 were randomized (roxadustat, n = 151; DA, n = 152). Weight‐adjusted AAD/6W increased with increasing ERI for roxadustat (ERI <3.3, 0.89 mg/kg; ERI ≥8.4, 1.51 mg/kg) and DA (ERI <3.3, 0.26 μg/kg; ERI ≥8.4, 0.91 μg/kg); the weight‐adjusted AAD/6W relative to within‐arm mean AAD/6W showed a trend toward increased DA doses for the ERI ≥8.4 category (P = .089). AAD/6W remained stable for roxadustat but increased for DA with decreasing baseline iron repletion markers. The relationship between roxadustat doses and end of treatment (EoT) hs‐CRP was not significant (estimated slope, −0.494; P = .814); a trend toward increased DA doses was observed with increasing EoT hs‐CRP (estimated slope, 2.973; P = .075). Roxadustat doses required to maintain target hemoglobin appear to be less affected by factors that underlie ESA hyporesponsiveness, relative to DA; roxadustat may be beneficial for patients hyporesponsive to ESAs.

Recommendations by the Asian Pacific society of nephrology (APSN) on the appropriate use of HIF-PH inhibitors

Renal anaemia is a common and important complication in patients with chronic kidney disease (CKD). The current standard‐of‐care treatment for renal anaemia in CKD patients involves ensuring adequate iron stores and administration of erythropoietin stimulating agents (ESA). Hypoxia inducible factor (HIF) is a key transcription factor primarily involved in the cellular regulation and efficiency of oxygen delivery. Manipulation of the HIF pathway by the use of HIF‐prolyl hydroxylase inhibitors (HIF‐PHI) has emerged as a novel approach for renal anaemia management. Despite it being approved for clinical use in various Asia‐Pacific countries, its novelty mandates the need for nephrologists and clinicians generally in the region to well understand potential benefits and harms when prescribing this class of drug. The Asian Pacific society of nephrology HIF‐PHI Recommendation Committee, formed by a panel of 11 nephrologists from the Asia‐Pacific region who have clinical experience or have been investigators in HIF‐PHI studies, reviewed and deliberated on the clinical and preclinical data concerning HIF‐PHI. This recommendation summarizes the consensus views of the committee regarding the use of HIF‐PHI, taking into account both available data and expert opinion in areas where evidence remains scarce.

The Asian Pacific society of nephrology HIF‐PHI Recommendation Committee summarizes the consensus views of the committee regarding the use of HIF‐PHI, taking into account both available data and expert opinion in areas where evidence remains scarce.

Roxadustat for CKD-related Anemia in Non-dialysis Patients

Introduction

Roxadustat is an oral hypoxia-inducible factor prolyl hydroxylase inhibitor that stimulates erythropoiesis and improves iron metabolism. We assessed the efficacy and tolerability of roxadustat in patients with chronic kidney disease (CKD)-related anemia not on dialysis.

Methods

ANDES was a global Phase 3 randomized study in which adults with stage 3–5 CKD not on dialysis received roxadustat or placebo. Patients were initially dosed thrice weekly; dose was titrated to achieve a hemoglobin level ≥11.0 g/dl, followed by titration for maintenance. The primary endpoints were change in hemoglobin (weeks 28–52) and proportion of patients achieving a hemoglobin response (hemoglobin ≥11.0 g/dl and increase ≥1.0 g/dl [baseline >8.0 g/dl], or increase ≥2.0 g/dl [baseline ≤8.0 g/dl]) (week 24). Treatment-emergent adverse events (TEAEs) and serious adverse events (TESAEs) were recorded.

Results

In roxadustat (n = 616) and placebo (n = 306) groups, hemoglobin mean (SD) change from baseline over weeks 28–52 was significantly larger for roxadustat (2.00 [0.95]) versus placebo (0.16 [0.90]), corresponding to least-squares mean difference of 1.85 g/dl (95% confidence interval [CI] 1.74–1.97; P < 0.0001). The proportion of patients achieving a response at week 24 was larger for roxadustat (86.0%; 95% CI 83.0%–88.7%) versus placebo (6.6%; 95% CI 4.1%–9.9%; P < 0.0001). The proportion of patients receiving rescue therapy at week 52 was smaller for roxadustat (8.9%) versus placebo (28.9%); hazard ratio, 0.19 (95% CI 0.14–0.28; P < .0001). The incidences of TEAEs and TESAEs were comparable.

Conclusion

This study showed that roxadustat corrected and maintained hemoglobin and was well tolerated in patients with CKD-related anemia not on dialysis (ClinicalTrials.gov NCT01750190).

Effect of Kidney Function and Dialysis on the Pharmacokinetics and Pharmacodynamics of Roxadustat, an Oral Hypoxia-Inducible Factor Prolyl Hydroxylase Inhibitor

Background and Objectives

Roxadustat is an orally active hypoxia-inducible factor prolyl hydroxylase inhibitor for anemia in chronic kidney disease. The pharmacokinetics, metabolic profile, and pharmacodynamics of roxadustat were investigated in subjects with different degrees of kidney function.

Methods

This phase 1 open-label study enrolled subjects with normal and severely impaired kidney function, and end-stage renal disease (ESRD) on continuous ambulatory peritoneal dialysis (CAPD) or automated peritoneal dialysis (APD) or hemodialysis/hemodiafiltration (HD/HDF). All subjects received a single 100-mg dose of oral roxadustat. Within a single-sequence, two-treatment period design (P1/P2), subjects with ESRD on HD/HDF received roxadustat 2 h after (P1) and 2 h before (P2) a dialysis session. Area under the plasma concentration–time curve (AUC) from administration to infinity (AUC_inf), maximum concentration (C_max), and terminal elimination half-life (t_1/2) were assessed for roxadustat; AUC and C_max were assessed for erythropoietin.

Results

Thirty-four subjects were enrolled and received roxadustat (normal kidney function, n = 12; severely impaired kidney function, n = 9; ESRD on CAPD/APD, n = 1; ESRD on HD/HDF, n = 12). The geometric least-square mean ratio of AUC_inf was 223% and 195% in subjects with severely impaired kidney function and ESRD on HD/HDF, respectively, relative to subjects with normal kidney function; C_max and t_1/2 were comparable. The pharmacokinetic profile of roxadustat was not affected by HD/HDF. AUC_inf and t_1/2 for the metabolites of roxadustat increased in subjects with kidney impairment. The AUC and C_max of erythropoietin increased in subjects with severely impaired kidney function or ESRD on HD/HDF. Roxadustat was well tolerated.

Conclusions

Kidney function impairment increased the AUC of roxadustat and its metabolites. The C_max and t_1/2 of roxadustat were comparable among groups. Roxadustat and its metabolites were not cleared by HD/HDF.

Clinical Trials Registration Number: NCT02965040.

Electronic supplementary material

The online version of this article (10.1007/s13318-020-00658-w) contains supplementary material, which is available to authorized users.

In Mixed Lymphocyte Reaction, the Hypoxia-Inducible Factor Prolyl-Hydroxylase Inhibitor Roxadustat Suppresses Cellular and Humoral Alloimmunity

Hypoxia-inducible factor (HIF) prolyl-hydroxylase inhibitors are currently used for the treatment of renal anemia. Since HIF affects immune cells, we evaluated the effect of such a drug, the roxadustat, on adaptive immunity. Cell proliferation was assessed in a two-way mixed lymphocyte reaction (MLR) with BrdU assay. In CD4⁺ T cells isolated from the two-way MLRs, western blotting was performed to detect the impact of roxadustat on HIF-1α and HIF-2α, the apoptotic marker cleaved caspase-3, and the master transcription factors of CD4⁺ T cells differentiation towards Th1, Th2, Th17, Treg and Tfh subsets. The signature cytokines of the above CD4⁺ T-cell subsets IFN-γ, IL-4, IL-17, IL-10, and IL-21 were measured in the supernatants. For assessing humoral immunity, we developed a suitable antibody-mediated complement-dependent cytotoxicity assay. Roxadustat stabilized HIF-1α and HIF-2α, suppressed cell proliferation, inhibited CD4⁺ T-cell differentiation into Th1 and Th17 subsets, while it favored differentiation towards Th2, Treg and Tfh. Roxadustat suppressed humoral immunity too. These immunosuppressive properties of roxadustat indicate that the recently introduced HIF prolyl-hydroxylase inhibitors in medical therapeutics may render the patients vulnerable to infections. This possibility should be further evaluated in clinical trials.

Current treatment practices for anemia in patients with chronic kidney disease and future opportunities with hypoxia-inducible factor prolyl hydroxylase inhibitors: a narrative review

PURPOSE

To investigate current treatment practices for anemia in patients with chronic kidney disease (CKD), issues surrounding current treatment practices, and the hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHI) that are currently in clinical trials. Treatment of anemia in patients with CKD has traditionally included iron supplementation and erythropoiesis-stimulating agents (ESAs). However, due to adverse cardiovascular (CV) events and hypo-responsiveness to ESA therapy, new agents are currently in clinical trials to treat anemia in patients with CKD. The HIF-PHIs stimulate erythropoiesis and regulate iron metabolism and are attractive alternatives to iron supplementation and ESAs.