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β-thalassemia is a genetic disorder that can cause chronic anemia that may require transfusions

β-thalassemia is seen throughout the world due to modern migration patterns but is most common in the areas shown below1

  • Approximately 68,000 people are born with β‑thalassemia worldwide each year1
  • Symptomatic β-thalassemia occurs in approximately 1 in every 100,000 individuals2
  • Approximately 55% are older than 20 years (in a study of 361 patients, mean age 23.2 years, in the Thalassemia Clinical Research Network)3

World Map of Beta-Thalassemia“


  • The prevalence of thalassemias in the US has increased by 7.5% over the past 5 decades due to immigration of people from affected regions; however, the exact prevalence in the US is not known4

β-thalassemia major and intermedia require varying degrees of RBC transfusions for management

β‑thalassemia minor β‑thalassemia intermedia β‑thalassemia major (Cooley’s anemia)

Patients typically have 1 normal functioning β‑globin (ex, β+/β or β0/β)5

Patients usually have partial β‑globin function (ex, β+/β0 or β+/β+)5

Patients typically have no β‑globin gene function (ex, β0/β0)5,8

Patients have mild or no anemia (typically asymptomatic)5,6

Patients may have mild-to-moderate anemia not dependent on transfusions5

Patients have the most severe type of anemia5,8

Patients usually do not require regular transfusions6,7

May require regular RBC transfusions if anemia becomes severe6,7

Patients require regular lifelong RBC transfusions5,7

Ineffective erythropoiesis is an underlying cause of anemia in patients with β‑thalassemia9

  • β-thalassemia results from inadequate (β+) or absent (β0) production or synthesis of β-globin chains, leading to an imbalance of α- and β-globin chains4,8
  • Unmatched α-globin chains may cause instability that leads to ineffective erythropoiesis10

Ineffective erythropoiesis in β‑thalassemia is characterized by9:

  • Increased proliferation of erythroid progenitors

  • Increased death of erythroid precursors

  • Impaired erythroid maturation

Ineffective erythropoiesis may lead to transfusion-dependent anemia9

There is a need to help address ineffective erythropoiesis, improve anemia, and reduce transfusions in adult patients with β‑thalassemia



REBLOZYL is indicated for the treatment of anemia in adult patients with beta thalassemia who require regular red blood cell (RBC) transfusions.

REBLOZYL is indicated for the treatment of anemia failing an erythropoiesis stimulating agent and requiring 2 or more red blood cell units over 8 weeks in adult patients with very low- to intermediate-risk myelodysplastic syndromes with ring sideroblasts (MDS-RS) or with myelodysplastic/myeloproliferative neoplasm with ring sideroblasts and thrombocytosis (MDS/MPN-RS-T).

REBLOZYL is not indicated for use as a substitute for RBC transfusions in patients who require immediate correction of anemia.




In adult patients with beta thalassemia, thromboembolic events (TEE) were reported in 8/223 (3.6%) REBLOZYL-treated patients. TEEs included deep vein thrombosis, pulmonary embolus, portal vein thrombosis, and ischemic stroke. Patients with known risk factors for thromboembolism (splenectomy or concomitant use of hormone replacement therapy) may be at further increased risk of thromboembolic conditions. Consider thromboprophylaxis in patients at increased risk of TEE. Monitor patients for signs and symptoms of thromboembolic events and institute treatment promptly.


Hypertension was reported in 10.7% (61/571) of REBLOZYL-treated patients. Across clinical studies, the incidence of Grade 3 to 4 hypertension ranged from 1.8% to 8.6%. In patients with beta thalassemia with normal baseline blood pressure, 13 (6.2%) patients developed systolic blood pressure (SBP) ≥130 mm Hg and 33 (16.6%) patients developed diastolic blood pressure (DBP) ≥80 mm Hg. In adult patients with MDS with normal baseline blood pressure, 26 (29.9%) patients developed SBP ≥130 mm Hg and 23 (16.4%) patients developed DBP ≥80 mm Hg. Monitor blood pressure prior to each administration. Manage new or exacerbations of preexisting hypertension using anti-hypertensive agents.

Embryo-Fetal Toxicity

REBLOZYL may cause fetal harm when administered to a pregnant woman. REBLOZYL caused increased post-implantation loss, decreased litter size, and an increased incidence of skeletal variations in pregnant rat and rabbit studies. Advise pregnant women of the potential risk to a fetus. Advise females of reproductive potential to use effective contraception during treatment and for at least 3 months after the final dose.



  • Serious adverse reactions occurred in 3.6% of patients on REBLOZYL. Serious adverse reactions occurring in 1% of patients included cerebrovascular accident and deep vein thrombosis. A fatal adverse reaction occurred in 1 patient treated with REBLOZYL who died due to an unconfirmed case of acute myeloid leukemia (AML)
  • Most common adverse reactions (at least 10% for REBLOZYL and 1% more than placebo) were headache (26% vs 24%), bone pain (20% vs 8%), arthralgia (19% vs 12%), fatigue (14% vs 13%), cough (14% vs 11%), abdominal pain (14% vs 12%), diarrhea (12% vs 10%) and dizziness (11% vs 5%)

Myelodysplastic Syndromes

  • Grade ≥3 (≥2%) adverse reactions included fatigue, hypertension, syncope and musculoskeletal pain. A fatal adverse reaction occurred in 5 (2.1%) patients
  • The most common (≥10%) adverse reactions included fatigue, musculoskeletal pain, dizziness, diarrhea, nausea, hypersensitivity reactions, hypertension, headache, upper respiratory tract infection, bronchitis, and urinary tract infection


It is not known whether REBLOZYL is excreted into human milk or absorbed systemically after ingestion by a nursing infant. REBLOZYL was detected in milk of lactating rats. When a drug is present in animal milk, it is likely that the drug will be present in human milk. Because many drugs are excreted in human milk, and because of the unknown effects of REBLOZYL in infants, a decision should be made whether to discontinue nursing or to discontinue treatment. Because of the potential for serious adverse reactions in the breastfed child, breastfeeding is not recommended during treatment and for 3 months after the last dose.

Please click here for full Prescribing Information for REBLOZYL.

References: 1. Origa R. β-Thalassemia. Genet Med. 2017;19(6):609-619. 2. Beta thalassemia. National Organization for Rare Diseases (NORD). Published 2018. Accessed January 6, 2021. 3. Vogiatzi MG, Macklin EA, Trachtenberg FL, et al. Differences in the prevalence of growth, endocrine and vitamin D abnormalities among the various thalassaemia syndromes in North America. Br J Haematol. 2009;146(5):546-556. 4. Sayani FA, Kwiatkowski JL. Increasing prevalence of thalassemia in America: implications for primary care. Ann Med. 2015;47(7):592-604. 5. Rund D, Rachmilewitz E. β-Thalassemia. N Engl J Med. 2005;353(11):1135-1146. 6. Rachmilewitz EA, Giardina PJ. How I treat thalassemia. Blood. 2011;118(13):3479-3488. 7. Ben Salah N, Bou-Fakhredin R, Mellouli F, Taher AT. Revisiting beta thalassemia intermedia: past, present, and future prospects. Hematology. 2017;22(10):607-616. 8. Cappellini MD, Porter JB, Viprakasit V, Taher AT. A paradigm shift on beta-thalassaemia treatment: how will we manage this old disease with new therapies? Blood Rev. 2018;32(4):300-311. 9. Oikonomidou PR, Rivella S. What can we learn from ineffective erythropoiesis in thalassemia? Blood Rev. 2018;32(2):130-143. 10. Rivella S. Ineffective erythropoiesis and thalassemias. Curr Opin Hematol. 2009;16(3):187-194.