ASN's Mission

ASN leads the fight to prevent, treat, and cure kidney diseases throughout the world by educating health professionals and scientists, advancing research and innovation, communicating new knowledge, and advocating for the highest quality care for patients.

learn more

Contact ASN

1401 H St, NW, Ste 900, Washington, DC 20005


The Latest on Twitter

Kidney Week

Abstract: PO0452

Number Needed to Treat with Roxadustat to Avoid One Transfusion or Intravenous Iron Administration in Anemia of Non-Dialysis-Dependent CKD

Session Information

Category: Anemia and Iron Metabolism

  • 200 Anemia and Iron Metabolism


  • Pecoits-Filho, Roberto, Arbor Research Collaborative for Health, Ann Arbor, Michigan, United States
  • Pollock, Carol A., University of Sydney, Sydney, New South Wales, Australia
  • Rastogi, Anjay, University of California Los Angeles, Los Angeles, California, United States
  • Provenzano, Robert, Wayne State University, Detroit, Michigan, United States
  • Lai, Rachel, FibroGen Inc, San Francisco, California, United States
  • Lee, Tyson T., FibroGen Inc, San Francisco, California, United States
  • Szczech, Lynda, FibroGen Inc, San Francisco, California, United States

Red blood cell (RBC) transfusion is the most common anemia treatment for non-dialysis-dependent chronic kidney disease (NDD CKD), but risks alloimmunization, which may delay or preclude kidney transplantation, and is associated with adverse events. Intravenous (IV) iron is recommended for poor response to oral iron, but requires travel to clinics. Roxadustat is an oral hypoxia-inducible factor prolyl hydroxylase inhibitor for anemia. It stimulates a coordinated erythropoietic response, increasing plasma endogenous erythropoietin levels and reducing hepcidin.


Data were pooled from 3 pivotal, randomized, phase 3 studies of roxadustat vs placebo NDD CKD populations. A phase 3 study of roxadustat vs darbepoetin alfa in NDD CKD was also analyzed. The number of patients needed to treat (NNT) with roxadustat for 1 year to avoid 1 RBC transfusion was calculated by taking the reciprocal after subtracting the RBC transfusion annualized event rate in the roxadustat arm from the event rate in the placebo arm. The same analysis was done for RBC transfusion and IV iron incidence rates.


Treating 4 patients with roxadustat vs placebo for 1 year is estimated to avoid 1 RBC transfusion. Treating 7 patients with roxadustat vs placebo for 1 year is estimated to avoid 1 patient needing 1 RBC transfusion, and treating 37 patients with roxadustat vs placebo is estimated to avoid 1 patient needing IV iron (Table). Rates of RBC transfusion (hazard ratio [HR]: 1.3 [95% CI 0.79, 2.11; p=0.3]) were comparable between roxadustat and darbepoetin alfa in the additional analyzed study, and a lower proportion of patients on roxadustat vs darbepoetin alfa required IV iron therapy use (HR: 0.45 [95% CI: 0.26, 0.78; p=0.004]).


In the pooled NDD CKD population, the NNTs to prevent RBC transfusion were low and indicative of patient benefit. Roxadustat reduced rates of RBC transfusions and IV iron use compared to placebo.


  • Commercial Support