fg-4592 and Kidney-Failure--Chronic

Anemia, a common complication of chronic kidney disease (CKD), has previously been attributed primarily to decreased production of erythropoietin. More recently, it has become apparent that the etiology of anemia involves several other factors, most notably dysfunctional iron metabolism, mediated via increased hepcidin activity and reduced clearance. Current management of anemia in patients with advanced CKD is based on erythropoiesis-stimulating agents and iron supplementation, along with red blood cell transfusions when necessary; however, safety considerations associated with these therapies highlight the need to pursue alternative treatment options targeting other mechanisms such as hypoxia-inducible factors (HIFs) that act as central regulators of erythropoiesis by coordinating a series of graded hypoxic responses.. This review discusses the discovery of the HIF pathway and its regulation via HIF prolyl hydroxylase enzymes in the context of erythropoiesis and iron metabolism. The rationale for targeting this pathway and the clinical development of HIF prolyl hydroxylase inhibitors are reviewed, with a commentary on the potential implications of this class of agents in CKD anemia management. Key Messages: Pharmacologic activation of the HIF pathway results in a transient pseudo-hypoxic state that stimulates erythropoiesis in CKD patients with anemia. Results from clinical studies of a number of HIF prolyl hydroxylase inhibitors are increasingly available and provide support for the continued evaluation of the risk-benefit ratio of this novel therapeutic approach to the treatment of anemia in CKD.

Topics: Anemia; Animals; Barbiturates; Blood Pressure; Disease Models, Animal; Drug Design; Drug Interactions; Glycine; Hepcidins; Humans; Hypoxia-Inducible Factor 1; Inflammation; Isoquinolines; Kidney Failure, Chronic; Picolinic Acids; Protein Domains; Pyrazoles; Triazoles

Roxadustat is an orally administered hypoxia-inducible factor prolyl hydroxylase inhibitor being developed for the treatment of anemia of chronic kidney disease (CKD). This European, phase 3, randomized, open-label, active-controlled study investigated efficacy and safety of roxadustat in patients with end-stage kidney disease on dialysis for at least 4 months.. Patients were randomized to switch from an erythropoiesis-stimulating agent (ESA) (epoetin alfa or darbepoetin alfa) to roxadustat three times/week or to continue their previous ESA. Roxadustat and ESA doses were adjusted to maintain hemoglobin within 10.0-12.0 g/dL during the treatment period (day 1 up to 52-104 weeks). Primary endpoints were hemoglobin change from baseline (CFB) to the average of weeks 28-36 without rescue therapy and hemoglobin CFB to the average of weeks 28-52 regardless of rescue therapy. Treatment-emergent adverse events (TEAEs) were assessed descriptively.. Of 1081 screened patients, 836 were randomized and received treatment (roxadustat, n = 415; ESA, n = 421). The least squares means (95% CI) of the treatment difference (roxadustat - ESA) for hemoglobin CFB to weeks 28-36 (without rescue therapy) and CFB to weeks 28-52 (regardless of rescue therapy) were 0.235 (0.132, 0.339) g/dL and 0.171 (0.082, 0.261) g/dL, respectively, demonstrating non-inferiority of roxadustat to ESA (non-inferiority margin of - 0.75 g/dL). The proportions of patients who achieved target hemoglobin without rescue therapy during weeks 28-36 were 84.2% (roxadustat) and 82.4% (ESA). Roxadustat was superior to ESA in decreasing LDL cholesterol from baseline to the average of weeks 12-28. Serious TEAEs occurred in 50.7% (roxadustat) and 45.0% (ESA) of patients. Common TEAEs in both treatment groups included hypertension, arteriovenous fistula thrombosis, headache, and diarrhea.. Roxadustat was non-inferior to ESAs in maintaining hemoglobin levels in this cohort of patients with anemia of CKD on dialysis for at least 4 months who were previously treated with ESAs. Observed TEAEs were consistent with previous studies.

Topics: Anemia; Glycine; Hematinics; Hemoglobins; Humans; Isoquinolines; Kidney Failure, Chronic; Renal Dialysis; Renal Insufficiency, Chronic; Research Design

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

Topics: Anemia; Epoetin Alfa; Erythropoietin; Glycine; Hematinics; Hemoglobins; Humans; Isoquinolines; Kidney Failure, Chronic; Recombinant Proteins; Renal Dialysis

Roxadustat (FG-4592), an oral hypoxia-inducible factor prolyl hydroxylase inhibitor that stimulates erythropoiesis, was evaluated in a phase 1b study in patients with end-stage renal disease with anemia on hemodialysis. Seventeen patients, on epoetin-alfa maintenance therapy with stable hemoglobin levels ≥10 g/dL, had epoetin-alfa discontinued on day 3 and were enrolled in this double-blind placebo-controlled study. Two cohorts were randomized 3:1 (roxadustat: placebo). Patients received single doses of roxadustat (1 or 2 mg/kg) or placebo 1 hour after hemodialysis on day 1 and 2 hours before dialysis on day 8. Maximum plasma concentration and area under the plasma concentration-time curve for patients receiving roxadustat were slightly more than dose proportional and elimination half-life ranged from 14.7 to 19.4 hours. Roxadustat was highly protein bound (99%) in plasma, and dialysis contributed a small fraction of the total clearance: only 4.56% and 3.04% of roxadustat recovered from the 1 and 2 mg/kg dose groups, respectively. Roxadustat induced transient elevations of endogenous erythropoietin that peaked between 7 and 14 hours after dosing and returned to baseline by 48 hours after dosing. Peak median endogenous erythropoietin levels were 96 mIU/mL and 268 mIU/mL for the 1- and 2-mg/kg doses, respectively, within physiologic range of endogenous erythropoietin responses to hypoxia at high altitude or after blood loss. No serious adverse events were reported, and there were no treatment- or dose-related trends in adverse event incidence.

Topics: Administration, Oral; Adult; Aged; Anemia; Area Under Curve; Dose-Response Relationship, Drug; Double-Blind Method; Erythropoiesis; Erythropoietin; Female; Glycine; Humans; Hypoxia; Hypoxia-Inducible Factor-Proline Dioxygenases; Isoquinolines; Kidney Failure, Chronic; Male; Middle Aged; Prolyl-Hydroxylase Inhibitors; Renal Dialysis; Treatment Outcome

Roxadustat (FG-4592) is an oral hypoxia-inducible factor prolyl-hydroxylase inhibitor that promotes erythropoiesis through increasing endogenous erythropoietin, improving iron regulation, and reducing hepcidin.. Phase 2, randomized (3:1), open-label, active-comparator, safety and efficacy study.. Patients with stable end-stage renal disease treated with hemodialysis who previously had hemoglobin (Hb) levels maintained with epoetin alfa.. Part 1: 6-week dose-ranging study in 54 individuals of thrice-weekly oral roxadustat doses versus continuation of intravenous epoetin alfa. Part 2: 19-week treatment in 90 individuals in 6 cohorts with various starting doses and adjustment rules (1.0-2.0mg/kg or tiered weight based) in individuals with a range of epoetin alfa responsiveness. Intravenous iron was prohibited.. Primary end point was Hb level response, defined as end-of-treatment Hb level change (ΔHb) of -0.5g/dL or greater from baseline (part 1) and as mean Hb level ≥ 11.0g/dL during the last 4 treatment weeks (part 2).. Hepcidin, iron parameters, cholesterol, and plasma erythropoietin (the latter in a subset).. Baseline epoetin alfa doses were 138.3±51.3 (SD) and 136.3±47.7U/kg/wk in part 1 and 152.8±80.6 and 173.4±83.7U/kg/wk in part 2, in individuals randomly assigned to roxadustat and epoetin alfa, respectively. Hb level responder rates in part 1 were 79% in pooled roxadustat 1.5 to 2.0mg/kg compared to 33% in the epoetin alfa control arm (P=0.03). Hepcidin level reduction was greater at roxadustat 2.0mg/kg versus epoetin alfa (P<0.05). In part 2, the average roxadustat dose requirement for Hb level maintenance was ∼1.7mg/kg. The least-squares-mean ΔHb in roxadustat-treated individuals was comparable to that in epoetin alfa-treated individuals (about -0.5g/dL) and the least-squares-mean difference in ΔHb between both treatment arms was -0.03 (95% CI, -0.39 to 0.33) g/dL (mixed effect model-repeated measure). Roxadustat significantly reduced mean total cholesterol levels, not observed with epoetin alfa. No safety concerns were raised.. Short treatment duration and small sample size.. In this phase 2 study of anemia therapy in patients with end-stage renal disease on maintenance hemodialysis therapy, roxadustat was well tolerated and effectively maintained Hb levels.

Topics: Adult; Aged; Aged, 80 and over; Anemia; Epoetin Alfa; Female; Glycine; Hematinics; Humans; Isoquinolines; Kidney Failure, Chronic; Male; Middle Aged; Renal Dialysis; Time Factors; Treatment Outcome; Young Adult

Anti-erythropoietin antibody-related pure red cell aplasia (anti-EPO PRCA) is a severe complication in patients who receive erythropoiesis-stimulating agents for nephrogenic anemia. The standard therapy is withdrawl of EPO and immunosuppression. Here, we present successful treatment of anti-EPO PRCA with roxadustat, a hypoxia-inducible factor prolyl hydroxylase inhibitor. A 39-year-old woman with end-stage renal disease received recombinant human erythropoietin (rhEPO) subcutaneously. Unfortunately, she developed anti-EPO PRCA and her hemoglobin dropped continuously, whereas she rejected immunosuppressive therapy. The patient failed to achieve spontaneous hematologic recovery with cessation of rhEPO alone, and she became transfusion dependent. Thus, she accepted our advice to try roxadustat for nephrogenic anemia. Surprisingly, after starting roxadustat treatment, her reticulocyte and hemoglobin improved gradually. Four months later, the bone marrow aspiration smear demonstrated a return to normal in erythroid cells. Besides, her anti-erythropoietin antibody converted to negative. All in all, this case reveals the potential effect of roxadustat on anti-EPO PRCA.

Topics: Adult; Erythropoietin; Female; Glycine; Humans; Isoquinolines; Kidney Failure, Chronic; Recombinant Proteins; Red-Cell Aplasia, Pure; Renal Dialysis

Topics: Anemia, Iron-Deficiency; Drugs, Investigational; Glycine; Humans; Hypoxia-Inducible Factor-Proline Dioxygenases; Isoquinolines; Kidney Failure, Chronic