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.

Background We evaluated the efficacy and safety of roxadustat vs. epoetin alfa for the treatment of chronic kidney disease (CKD) related anemia in patients new to dialysis. Methods This was a phase 3, open-label, epoetin alfa-controlled trial. Eligible adults were on hemodialysis/peritoneal dialysis for ≥2 weeks and ≤4 months before randomization and had mean hemoglobin ≤10.0 g/dL. Primary endpoints were mean hemoglobin (g/dL) change from baseline averaged over weeks 28–52 regardless of rescue therapy (non-inferiority criterion: lower limit of 95% CI for treatment difference > −0.75) and percentage of patients achieving a hemoglobin response between weeks 1–24 censored for rescue therapy (non-inferiority margin for between-group difference: −15%). Adverse events were monitored. Results The intention-to-treat population included patients randomized to roxadustat (n = 522) or epoetin alfa (n = 521). Mean (SD) hemoglobin 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 a hemoglobin response were 88.2% and 84.4% in the roxadustat and epoetin alfa groups. 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 hemoglobin levels compared to epoetin alfa. Roxadustat had an acceptable safety profile.

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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 openlabel (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. | INTRODUCTIONMyelodysplastic syndromes (MDS) affect about 60 000 Americans, with an annual incidence of 4.5 per 100 000 people. [1][2][3] About 77% of patients diagnosed with MDS have a disease that is classified as lower risk (LR-MDS) at diagnosis, as defined by the revised International Prognostic Scoring System (IPSS-R) score of ≤ 3.5. [4][5][6] More than 90% of patients diagnosed with MDS have anemia at the time of their diagnosis, and over 60% of patients with MDS experience severe anemia at later stages of their disease. 7,8 Currently, there are limited anemia treatments with variable response rates approved for patients with LR-MDS in the US and EU for small subsets of LR-MDS patients. Epoetin alfa is approved in Europe for patients with LR-MDS with symptomatic anemia (hemoglobin < 10 g/dL). It was also granted orphan drug designation in the US for the study of adult patients with MDS. Red blood cell Clinical trial registration: NCT03263091.

Background: Roxadustat (FG-4592) is an oral hypoxia-inducible factor (HIF) prolyl hydroxylase inhibitor that promotes coordinated erythropoiesis through HIF-mediated transcription. Transient, intermittent HIF activation by roxadustat mimics a physiological response that increases endogenous erythropoietin (EPO) production to near physiologic range and stimulates EPO receptor synthesis. In addition, roxadustat promotes iron metabolism by reducing serum hepcidin to allow absorption of iron from the gut and mobilize iron from cellular storage making more iron available for erythropoiesis. Roxadustat corrected and maintained hemoglobin (Hb) in chronic kidney disease patients in multiple Phase 3 trials irrespective of underlying inflammation. In these studies, roxadustat-treated patients required less IV iron to correct and maintain Hb compared to erythropoiesis-stimulating agent (ESA)-treated patients. MDS is characterized by symptomatic anemia and many patients require RBC transfusion and/or ESA treatment. As response to ESAs varies across sub-populations with limited durability, there is an unmet need for treatment of anemia in LR-MDS. This is the first study to evaluate the effect of roxadustat in treating anemia in primary MDS patients. Methods: This is a two-part study; an open-label (OL), dose-finding segment (N=24) followed by a randomized double-blind (DB) placebo-controlled segment (N=156, 3:2 ratio of roxadustat to placebo). The primary goal of the OL segment is to identify the starting roxadustat dose-level for the DB segment. A total 24 patients in the OL segment have been enrolled in three sequential cohorts with 8 patients in each starting dose cohort (1.5, 2.0, or 2.5 mg/kg). RBC transfusion has been allowed per institutional criteria. Eligible patients were very low, low or intermediate risk primary MDS patients based on the International Prognostic Scoring System Revised classification with &lt;5% bone marrow blasts; had baseline Hb &lt; 10.0 g/dL; were &gt;18 years old; and had LTB defined as receiving 1-4 RBC units per 8 week period. Patients were ineligible if they used an ESA within 8 weeks of the study start; had endogenous EPO levels &gt;400 mIU/mL, or had a del(5q) cytogenetic abnormality. Roxadustat was administered TIW with doses titrated every 8 weeks per a dosing algorithm based on Hb response and transfusion need. Data from the OL segment were evaluated to identify the starting dose for the DB segment (currently enrolling). The primary endpoint is transfusion independence (TI) for ≥56 consecutive days during the first 28 weeks of treatment. The proportion of patients who achieve ≥50% reduction in RBC transfusion over any 8 weeks compared to baseline (8 weeks prior to Day 1) and proportion of patients who achieve TI for ≥20 consecutive weeks are evaluated. Safety and tolerability are assessed by adverse event reporting, percentage of patients progressing to acute myeloid leukemia (AML), and clinical laboratory values. Results: Twenty-four transfusion dependent, LR-MDS patients were enrolled in the OL segment of this global Phase 3 trial. Nine patients (38%) achieved TI for at least 56 consecutive days within the first 28 weeks.Three of 9 patients started at 1.5 mg/kg dose, 1 patient started at 2.0 mg/kg dose and 5 patients started at 2.5 mg/kg dose. At the time of achieving TI, 7 of 9 patients (78%) were on 2.5 mg/kg dose, 1 patient (11%) was on 2.0 mg/kg dose (started with 1.5 mg/kg dose) and one patient (11%) was on 1.5 mg/kg dose. Four patients remained TI for &gt;20 weeks (one at 1.5 mg/kg dose level and three at 2.5 mg/Kg dose-level). One additional patient achieved TI after the initial 28-week dosing period at a dose-level of 3.5 mg/kg (starting dose 2.0 mg/kg). A total of 14 patients (58%) achieved a ≥50% reduction in RBC units in any 8-week period compared to baseline (range of 2-4 RBC units in 8 weeks before dosing); 12 of these patients were at ≥ 2.5 mg/kg dose level when achieving a 50% reduction in transfusion without need for IV iron. The overall safety profile observed is consistent with the patient population under study. Six patients reported 8 treatment-emergent SAEs with none being fatal. No patient has progressed to AML. Full results from the OL segment of the study will be presented. Conclusion: Based on the observed response (TI and transfusion reduction) and safety profile in LR-MDS patients, 2.5 mg/kg was selected as the starting dose for the ongoing 156-patient DB portion of the trial. Disclosures Harrup: Cooperative Trial Group for NeuroOncolog: Other: Collaborative Clinical Trials Group; Cancer Council of Tasmania: Membership on an entity's Board of Directors or advisory committees. Mittelman:Novartis: Honoraria, Research Funding, Speakers Bureau. Bradley:FibroGen Inc.: Employment, Equity Ownership. Saha:FibroGen Inc.: Employment, Equity Ownership. Bartels:FibroGen Inc.: Employment, Equity Ownership. Robert:FibroGen Inc.: Employment, Equity Ownership. Yu:FibroGen Inc.: Employment, Equity Ownership.