Tadao Akizawa

Prof. Dr. Tadao Akizawa


Research Focus & Metrics

Academic Career Length

40Years (1987-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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3 June 2020 in Journal of the American Society of Nephrology
Verified
Journal Article
Closed access
PDF file
TATadao Akizawa
Tadao Akizawa
MIManabu Iwasaki
Manabu Iwasaki
YYYusuke Yamaguchi
Yusuke Yamaguchi
YMYoshikatsu Majikawa
Yoshikatsu Majikawa
MRMichael Reusch
Michael Reusch
Significance Statement: Although generally effective at raising hemoglobin levels to treat dialysis-dependent CKD anemia, erythropoiesis-stimulating agents such as darbepoetin alfa have safety issues and are less effective in patients with inflammation. In this randomized controlled trial in stable Japanese patients on hemodialysis previously treated with erythropoiesis-stimulating agents, the authors compared roxadustat—an oral hypoxia-inducible factor prolyl hydroxylase inhibitor previously shown to be effective in treating CKD anemia—with darbepoetin alfa. The study found that roxadustat was effective in maintaining hemoglobin within target levels and that its efficacy was noninferior to darbepoetin alfa. Consistent with previous findings, roxadustat showed an acceptable safety profile. These data confirm that oral roxadustat is a valid alternative to injectable erythropoiesis-stimulating agents for dialysis-dependent CKD anemia. Background: Roxadustat is an oral hypoxia-inducible factor prolyl hydroxylase inhibitor approved in China for dialysis-dependent CKD anemia. Methods: This phase 3, 24-week, double-blind, double-dummy study evaluated roxadustat’s noninferiority to darbepoetin alfa for hemodialysis-dependent CKD anemia. We randomly assigned Japanese patients to oral roxadustat three times weekly or to darbepoetin alfa injections once weekly, titrating doses to maintain hemoglobin between 10–12 g/dl. The primary end point was change of average hemoglobin from baseline to weeks 18–24 (∆Hb18–24). Secondary end points were average hemoglobin and proportion of patients with hemoglobin between 10–12 g/dl (maintenance rate) at weeks 18–24, and iron parameters. Safety assessments included treatment-emergent adverse events and adjudicated ophthalmologic findings. Results: We randomly assigned 303 patients to roxadustat (n=151) or darbepoetin alfa (n=152). The difference between roxadustat and darbepoetin alfa in ∆Hb18–24 was −0.02 g/dl (95% confidence interval, –0.18 to 0.15), confirming roxadustat’s noninferiority to darbepoetin alfa. Average hemoglobin at weeks 18–24 with roxadustat was 10.99 g/dl (95% confidence interval: 10.88 to 11.10), confirming its efficacy. Among patients with one or more hemoglobin value during weeks 18–24, the maintenance rate was 95.2% with roxadustat and 91.3% with darbepoetin alfa. Serum iron, ferritin, and transferrin saturation remained clinically stable with roxadustat; transferrin and total iron binding capacity increased through week 4 before stabilizing. Common treatment-emergent adverse events were nasopharyngitis, shunt stenosis, diarrhea, contusion, and vomiting. The proportion of patients with new or worsening retinal hemorrhage was 32.4% with roxadustat and 36.6% with darbepoetin alfa. We observed no clinically meaningful changes in retinal thickness groups. Conclusions: Roxadustat maintained hemoglobin within 10–12 g/dl in patients on hemodialysis and was noninferior to darbepoetin alfa. Treatment-emergent adverse events were consistent with previous reports. Clinical Trial registry name and registration number: A Study of Intermittent Oral Dosing of ASP1517 in Hemodialysis Chronic Kidney Disease Patients with Anemia, NCT02952092 (ClinicalTrials.gov)

20 June 2019 in Therapeutic Apheresis and Dialysis
Verified
Journal Article
Open access
PDF file
TATadao Akizawa
Tadao Akizawa
TOTetsuro Otsuka
Tetsuro Otsuka
MRMichael Reusch
Michael Reusch
MUMai Ueno
Mai Ueno
Roxadustat is an oral hypoxia‐inducible factor prolyl hydroxylase inhibitor developed to treat anemia in chronic kidney disease (CKD) patients. This Phase 3, randomized, open‐label, 24‐week study investigated the efficacy and safety of roxadustat in Japanese CKD patients with anemia on peritoneal dialysis (PD) who were previously treated or not treated with erythropoiesis stimulating agents (ESAs). Patients not previously receiving ESA (ESA‐Naïve group) were randomized to roxadustat at a starting dose of 50 or 70 mg three times weekly; patients previously receiving ESA (ESA‐Converted group) switched from ESA to roxadustat 70 or 100 mg three times weekly depending on the prior ESA dose. Outcomes included maintenance rate of average hemoglobin (Hb) level within 10–12 g/dL at weeks 18–24, cumulative response rate at end of treatment (Hb thresholds, 10.0 g/dL or 10.5 g/dL; Hb increase, ≥1.0 g/dL), and average Hb levels at weeks 18–24. Safety was assessed by occurrence of treatment‐emergent adverse events (TEAEs). Fifty‐six patients were enrolled (ESA‐Naïve, n = 13; ESA‐Converted, n = 43). Maintenance rates (weeks 18–24) were 92.3% (95% CI: 64.0–99.8; ESA‐Naïve) and 74.4% (95% CI: 58.8–86.5; ESA‐Converted). Cumulative response rate was 100.0% in the ESA‐Naïve group. Average Hb levels (weeks 18–24) were 11.05 g/dL (95% CI: 10.67–11.42; ESA‐Naïve) and 10.93 g/dL (95% CI: 10.73–11.13; ESA‐Converted). Common TEAEs included nasopharyngitis and back pain. Roxadustat was well tolerated and effective in maintaining target Hb levels in CKD patients on PD who were previously treated or not treated with ESA.

5 April 2019 in Advances in Therapy
Verified
Journal Article
Open access
PDF file
TATadao Akizawa
Tadao Akizawa
MIManabu Iwasaki
Manabu Iwasaki
TOTetsuro Otsuka
Tetsuro Otsuka
MRMichael Reusch
Michael Reusch
TMToshihiro Misumi
Toshihiro Misumi
This study evaluated efficacy and safety/tolerability of roxadustat, an oral hypoxia-inducible factor prolyl hydroxylase inhibitor, in Japanese anemic non-dialysis-dependent chronic kidney disease (NDD-CKD) patients.

24 June 2008 in Nephrology Dialysis Transplantation
Verified
Journal Article
Open access
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TATadao Akizawa
Tadao Akizawa
RPRonald L. Pisoni
Ronald L. Pisoni
TATakashi Akiba
Takashi Akiba
ASAkira Saito
Akira Saito
SFShunichi Fukuhara
Shunichi Fukuhara
KKKiyoshi Kurokawa
Kiyoshi Kurokawa
Background. Japanese haemodialysis (HD) patients not only have a very low mortality and hospitalization risk but also low haemoglobin (Hb) levels. Internationally, anaemia is associated with mortality, hospitalization and health-related quality of life (QoL) measures of HD patients. Methods. Longitudinal data collected from 1999 to 2006 from 60 to 64 representative Japanese dialysis units participating in the Dialysis Outcomes and Practice Patterns Study (DOPPS) were used to describe anaemia management practices and outcomes for Japanese HD patients. Results. From 1999 to 2006, patient mean Hb increased from 9.7 g/dl to 10.4 g/dl, and the percentage of facilities with median Hb ≥10 g/dl increased from 27% to 75%. Hb was measured in the supine position for 90% of patients, resulting in substantially lower reported Hb values than those seen in other countries. As of 2006, erythropoietin (Epo) was prescribed to 83% of HD patients; mean Epo dose was 5231 units/week; intravenous (IV) iron use was 33% and median IV iron dose was 160 mg/month. Many patient- and facility-level factors were significantly related to higher Hb. A consistent overall pattern of lower mortality risk with higher baseline Hb levels was seen (RR = 0.89 per 1 g/dl higher Hb, P = 0.003). Facilities with median Hb ≥10.4 displayed a lower mortality risk (RR = 0.77, P = 0.03) versus facility median Hb <10.4 g/dl. Lower Hb levels were not significantly related to hospitalization risk, but were associated with lower QoL scores. Conclusions. These results provide detailed information on anaemia management practices in Japan and the relationships of anaemia control with outcomes, with implications of anaemia management worldwide.

1 July 2021 in Kidney International Reports
Verified
Journal Article
Open access
TATadao Akizawa
Tadao Akizawa
MIManabu Iwasaki
Manabu Iwasaki
TOTetsuro Otsuka
Tetsuro Otsuka
YYYusuke Yamaguchi
Yusuke Yamaguchi
MRMichael Reusch
Michael Reusch
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). 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. 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. 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.

30 January 2019 in American Journal of Nephrology
Verified
Journal Article
Open access
PDF file
TATadao Akizawa
Tadao Akizawa
MNMasaomi Nangaku
Masaomi Nangaku
TYTakuhiro Yamaguchi
Takuhiro Yamaguchi
MAMasanobu Arai
Masanobu Arai
RKRyosuke Koretomo
Ryosuke Koretomo
HHHideki Hirakata
Hideki Hirakata
Background: Enarodustat (JTZ-951) is an oral hypoxia-inducible factor prolyl hydroxylase inhibitor that mimics adaptive responses to hypoxic conditions and may provide a new therapeutic approach for managing anemia in patients with chronic kidney disease (CKD). We evaluated the efficacy, safety, and maintenance dose of enarodustat in anemic patients with CKD not on dialysis. Methods: Erythropoiesis-stimulating agent (ESA) naïve patients (correction group) and patients on a stable dose of ESA (conversion group) were randomized to receive 2, 4, or 6 mg of enarodustat or placebo once daily for 6 weeks in a double-blind manner (Period 1) followed by 24 weeks of open enarodustat treatment to maintain their hemoglobin (Hb) levels within a target range of 10.0–12.0 g/dL in reference to a dose adjustment algorithm (Period 2). Results: In the correction group, Hb level increase rate per week increased in a dose-response manner. The proportion of subjects in the conversion group who maintained Hb levels within ± 1.0 g/dL of baseline did not differ between each enarodustat arm and placebo arm during Period 1. Over 70% of subjects in both groups maintained Hb levels within the target range at the end of treatment in Period 2. The mean prescribed doses were 3.58 and 3.74 mg/day in the correction group and the conversion group, respectively. Enarodustat was associated with decreases in hepcidin and ferritin and increased total iron-binding capacity and was generally well tolerated. Conclusions: Enarodustat corrects and maintains Hb levels in anemic patients with CKD not on dialysis.