Yotsumoto Fertrin_Kleber
Assistant Professor, Division of Hematology
University of Washington

Faculty Information


Dr. Fertrin’s research aims to investigate novel potential approaches to treat and cure patients with hemolytic anemias, such as sickle cell disease and thalassemias, to reduce the need for blood transfusion, and to prevent and treat excess body iron.

Originally starting his career in Brazil, Dr. Fertrin’s early interest in genetics led him to study the clinical aspects and molecular biology of sickle cell disease and thalassemias, which are very prevalent in his home country, along with other rare anemias leading to the need for red blood cell transfusions and, consequently, to iron overload. His previous research reported on how iron metabolism regulation varies depending on the underlying defect in erythropoiesis (Fertrin et al., Am J Hematol 2014), and on the spectrum of tissue iron overload across different disorders, affecting most frequently the liver, but also more rarely the brain (Borges et al., Am J Neuropsych 2019) and the heart (Tavares et al., Transfus Med Rev 2019). In clinical research, he participated in the design and execution of the first clinical trials to demonstrate the effectiveness of adjuvant amlodipine to improve iron chelation in patients with transfusion-dependent thalassemia (Fernandes et al., Am J Med 2013 and Blood 2016) and participated in the multicenter clinical trial that led to the approval of crizanlizumab as treatment for recurrent vaso-occlusive crises in patients with sickle cell disease.

Dr. Fertrin’s current research projects explore novel medications that can reduce anemia and iron overload in pyruvate kinase deficiency and thalassemias, as well as decrease the frequency of painful episodes in sickle cell disease. He is also interested in the use of curative approaches for hemoglobin disorders, including gene editing, and in innovative therapeutic strategies that can mitigate the need for red blood cell transfusions more broadly or improve tissue iron removal in patients who develop iron overload.

Education & Training: 
University of Campinas
Campinas, Brazil
Residency in Internal Medicine
University of Campinas
Campinas, Brazil
Fellowship in Hematology and Transfusion Medicine
University of Campinas
Campinas, Brazil
Research Post-doctoral Fellowship
National Heart, Lung, and Blood Institute (NIH)
Bethesda, MD
Placed with Distinction at the International Mathematics and Verbal Talent Search by the Center for the Advancement of Academically Talented Youth (CTY), Johns Hopkins University, Baltimore, MD
XI Adolfo Lutz Award for Best Undergraduate Research Abstract in Internal Medicine and VI Lopes de Faria Award for Best Overall Undergraduate Research Abstract, School of Medical Sciences, University of Campinas, Campinas, Brazil
American Society of Hematology Abstract Achievement Award
European Hematology Association-American Society of Hematology Translational Research Training in Hematology (TRTH)
American Society of Hematology Clinical Research Training Institute in Latin America
American Society of Hematology Advanced Clinical Research Training Institute in Latin America
Mailing Address: 

825 Eastlake Ave E
MS CE3-300 PO Box 19023
Seattle, WA, 98109-1023

Research & Clinical Interests
Research Interests: 

Sickle cell disease, thalassemias, transfusion iron overload, hereditary hemochromatosis, and other iron-loading anemias

Clinical Interests: 

General hematology; anemias, such as sickle cell disease, thalassemias, and autoimmune hemolytic anemia; iron metabolism disorders, such as hereditary hemochromatosis and transfusion iron overload; disorders of hemostasis, such as thrombocytopenia and thrombosis.