About Thalassemia

Thalassemia is a genetic blood disorder where the body cannot produce normal hemoglobin, which is needed for healthy red blood cells. It is not contagious and cannot be spread through personal contact. Understanding thalassemia is the first step toward better management and treatment.

Disease

Thalassemia is a genetic blood disorder where the body cannot produce normal hemoglobin, which is needed for healthy red blood cells. It is not contagious and cannot be spread through personal contact.

Thalassemia is most common in people of Chinese, South Asian, Middle Eastern, Mediterranean, or African descent. The only way to know if you carry the thalassemia trait is through a special blood test called hemoglobin electrophoresis. If you’re in a high-risk group, ask your doctor for this test.

Thalassemia – ineffective erythropoiesis which leads to chronic hemolytic anemia. Severity depends on the type of inherited mutations and secondary molecular modifiers. Thalassemia – ineffective erythropoiesis which leads to chronic hemolytic anemia. Severity depends on the type of inherited mutations and secondary molecular modifiers.

Thalassemia occurs when one gene is inherited from each parent, leading to three types:

Thalassemia Minor

In Thalassemia Minor, the hemoglobin genes are inherited at conception—one from the mother (egg) and one from the father (sperm). People who inherit the thalassemia trait in one gene are known as carriers and are said to have thalassemia minor. The only way to confirm if you carry the trait is through a special blood test called hemoglobin electrophoresis, which can identify the gene. Carriers of thalassemia minor may become mildly anemic.

If you, your parents, or ancestors come from regions where thalassemia is common, ask your doctor for this test. It’s important to know if you are a carrier. If both parents carry the thalassemia minor trait, there is a 25% (1 in 4) chance of having a child with thalassemia major. Raising awareness is key to prevention.

Thalassemia Intermedia

Thalassemia Intermedia is caused by inheriting one severe thalassemia gene and one milder gene. Children with this condition usually develop symptoms later than those with thalassemia major, often around age 2.

Thalassemia patients may be categorized as having either transfusion-dependent thalassemia (TDT) or non-transfusion-dependent Thalassemia (NTDT). Hemoglobin level largely determines whether transfusion therapy is required.

Non Transfusion Dependent Thalassemia (NTDT)

NTDT Patients tend to present with mild to moderate anemia and they are typically diagnosed later in childhood compared to transfusion dependent patients.

Transfusions in Thalassemia Intermedia

The symptoms associated with anemia are severe enough that routine transfusions are initiated. In children, symptoms may include failure to grow.

The severity of thalassemia intermedia isn’t based solely on hemoglobin levels. It also depends on the individual’s sense of well-being, their growth rate, and their overall development. Unfortunately, there is no clear distinction between thalassemia intermedia and thalassemia major.

Thalassemia Major

Thalassemia Major occurs when a child inherits two mutated genes, one from each parent. Children with thalassemia major usually develop symptoms of severe anemia within their first year. They are unable to produce normal adult hemoglobin, leading to chronic fatigue and failure to thrive.

Two key consequences of thalassemia are severe anemia and the expansion of bone marrow as the body tries to produce more red blood cells. This results in poor growth, physical impairments, bone deformities, fragile bones, and enlargement of the liver and spleen. Without treatment, thalassemia major is fatal within the first decade of life. The only effective treatment is regular blood transfusions combined with iron chelation therapy.

Living With Thalassemia

Thalassemia is a lifelong condition that brings unique challenges. Ongoing medical treatment can take a toll on both patients and families, leading to emotional distress and affecting treatment outcomes and quality of life.

The Guidelines for the Clinical Care of Patients with Thalassemia in Canada recommend access to psychologists and social workers who understand the specific challenges faced at different life stages. Education, work, relationships, self-esteem, societal expectations, and parenthood can all be sources of stress for those with thalassemia.

Support and resources are essential to help patients manage their condition, build self-care skills, and maintain a healthy lifestyle.

For assistance, please contact us.

Treatment

Regular blood transfusions provide thalassemia patients with the red blood cells they need to survive. However, once these cells break down, the body is left with excess iron.

While iron is essential, too much can cause organ failure and death. This excess iron must be removed (chelated) as it accumulates in vital organs like the heart and liver.

Fortunately, iron chelation drugs have greatly improved the outlook for patients with transfusion-dependent thalassemia.

Along with regular blood transfusions and chelation therapy to prevent iron overload, patients are monitored to detect and manage any complications that come from the disease or the treatments.

Blood Safety

Thalassemia patients require regular blood transfusions every 1-5 weeks, a treatment that continues throughout their lives. This makes the safety and supply of blood a critical concern.

In Canada, the blood supply is very safe. Potential drops in the blood supply or emerging blood-borne infections are remote risks for patients who receive blood.

Blood-Borne Pathogens

HIV: HIV is a blood-borne pathogen and sexually transmitted disease. From 1978 to 1985, blood supply contamination with HIV peaked. Screening began in 1985, and since then, HIV transmission through blood has been rare.
Hepatitis B: Hepatitis B is a blood-borne and sexually transmitted disease that causes liver inflammation. A vaccine is available and recommended for all blood recipients, including thalassemia patients. Each province in Canada offers large-scale immunization, and every blood donation is tested for HBV.
Hepatitis C: Hepatitis C is transmitted through blood-to-blood contact. Transmission peaked in the 1980s but has dropped significantly since testing began in 1990. Each blood donation is tested for Hepatitis C Virus and the risk of getting HCV from a blood transfusion in Canada is extremely low.

Other Risks

Bacterial Infections: Such as Yersinia.
Other Pathogens: Hepatitis G, TTV (Transfusion-Transmitted Virus), SEN-V, and vCJD.

Canadian Blood Supply

Thalassemia patients in Canada are fortunate to have a well-managed blood supply, though they still face concerns about potential shortages and contamination risks.

The Thalassemia Foundation of Canada (TFC) strongly believes in the safety of the blood system. TFC advocates for continued evaluation and maintenance of the system to ensure the safety of blood donors and recipients alike. Thalassemia patients depend on a safe and reliable blood supply, as they have no alternative.

Iron Overload

What is Iron Overload?
Iron overload occurs when there is too much iron in the body. Even mild cases increase the risk of liver disease (including cirrhosis and cancer), heart attack, heart failure, diabetes, osteoporosis, osteoarthritis, hypothyroidism, metabolic syndrome, hypogonadism, and can lead to premature death.

What Causes Iron Overload?
Iron overload can be genetic or acquired through frequent blood transfusions, iron injections, or excessive intake of iron supplements. For those receiving regular blood transfusions, iron can accumulate to toxic levels, requiring iron chelation therapy to remove it.

What Treatments are Available for Iron Overload?
Chelation therapy is used to remove excess iron from the body and prevent iron overload. Commonly used chelating agents include deferoxamine, deferiprone, and deferasirox.

In Canada, a main treatment for every transfusion-dependent thalassemia patient is the use of at least one of these three chelator options. In some cases, two of these medications are used in combination.

Chelation Therapy Options

Deferoxamine (Desferal): In use since 1978, given via 10-12 hour subcutaneous infusion with a pump. Effective but often uncomfortable; in severe cases, given intravenously 24/7 via a portacath or PICC line.
Deferasirox (Exjade, Jadenu): Available since 2007, taken once daily as a slurry or (since 2016) in tablet form.
Deferiprone (Ferriprox): Since 2015, taken up to 3 times daily; extended-release version approved in Canada in 2023 offers more flexibility but is not yet available nationwide.

Chelation in pill form (Deferasirox or Deferiprone) improves patients’ quality of life and encourages better compliance.

Chelation therapy is typically started once iron overload is detected, usually through regular monitoring of serum ferritin levels and iron concentrations in the heart and liver. Typically, iron chelation treatment begins in a transfusion-dependent thalassemia child between the ages of 2 and 5 years old.

Speak to your doctor to determine the best treatment option for you.

For more information on financial support for thalassemia patients, please click here.

Adherence to treatment and regular follow-up with healthcare providers are essential for maintaining quality of life and reducing the risk of long-term complications. Patients in Canada who adhere to treatment can grow and develop normally, with relatively healthy heart, liver and endocrine function. Many patients are now living into their sixties and some have children, some work full-time and some have pursued post-secondary education.

The Guidelines for the Clinical Care of Patients with Thalassemia in Canada provide detailed recommendations to ensure patients receive the best possible care.

Haploidentical Hematopoietic Stem Cell Transplantation

Haploidentical hematopoietic stem cell transplantation (haplo-HSCT) is a curative, effective option for transfusion-dependent beta-thalassemia when a fully matched donor is unavailable, often using a parent as a half-matched donor. Utilizing advanced techniques like post-transplant cyclophosphamide (PT-Cy) or T-cell depletion, studies report high overall survival (up to 95–96%) and successful engraftment, offering a vital alternative to lifelong transfusion ⁽⁴⁾.

Alpha/Beta T-cell Depleted Transplantation

Alpha/beta T-cell depletion is a technique used in haploidentical stem cell transplantation to selectively remove the T-cells most likely to cause graft-versus-host disease (GVHD) while preserving other immune cells that support engraftment and immune recovery. A 2025 study by Kleinschmidt et al. demonstrated the successful use of αβ T-cell depleted haploidentical stem cell transplantation for pediatric and young adult patients with transfusion-dependent thalassemia, achieving sustained engraftment and transfusion independence ⁽⁴⁾.

Improvements in Transplant Medicine

Bone marrow transplants, while they can be successful, are limited by the lack of fully matched donors. Familial HLA identical matching (12/12 on all 6 loci is preferred) is considered the gold standard for optimal outcomes ⁽⁵⁾. The majority of patients do not have a familial match. Transplants also tend to be most efficacious and safe when conducted early in life.

Drugs such as Abatacept are making bone marrow transplants safer by protecting patients against graft-versus-host disease (GVHD). A recent study resulted in 100% disease-free survival ⁽¹⁾.

Haploidentical Bone Marrow Transplantation for Beta Thalassemia Major

Recent advancements in haploidentical bone marrow transplantation (haplo-HSCT) for beta thalassemia major have shown promising results:

Novel Conditioning Regimens: A December 2024 study introduced a modified myeloablative conditioning regimen using busulfan, cyclophosphamide, fludarabine, and antithymocyte globulin (ATG). This approach has resulted in reduced complication rates and improved safety and survival outcomes for patients ⁽³⁾.
Successful Case Reports: Reports from Annals of Hematology documented the successful use of haplo-HSCT in pediatric patients with congenital dyserythropoietic anemia and beta thalassemia. These cases highlighted the versatility of haploidentical transplants in managing complex conditions, with both patients achieving sustained engraftment and transfusion independence.
Optimizing Engraftment and GVHD Management: Ongoing research is focused on enhancing engraftment strategies and managing graft-versus-host disease (GVHD), particularly in pediatric populations, to improve transplant outcomes ⁽³⁾.

Overall, these findings suggest a positive outlook for haploidentical transplantation in treating beta thalassemia major, with significant improvements in both safety and efficacy.

References

Khandelwal P, Ibrahimova A, Lane A, Grimley M, Davies SM, Jodele S. Abatacept improves posttransplant survival and reduces endothelial injury syndromes in β-thalassemia major. Blood Adv. 2025 Sep 15;9(24):6370–6379. doi: 10.1182/bloodadvances.2025017197
Testa U, Castelli G, Pelosi E. Curative Approach to the Treatment of Beta-Thalassemia and Sickle Cell Disease with Hematopoietic Stem Cell Transplantation.
Ali A, Ali MA, Afridi A, et al. Efficacy and safety of Busulfan–Fludarabine versus Busulfan–Cyclophosphamide as a conditioning regimen prior to hematopoietic stem cell transplant in hematologic malignancy patients: a meta-analysis of randomized controlled trials and observational studies. Adv Hematol. 2026 Jan 16;17:20406207251407534. doi: 10.1177/20406207251407534
Kleinschmidt K, Penkivech G, Troeger A, et al. αβ T-cell depleted haploidentical stem cell transplantation for pediatric and young adult patients with transfusion-dependent thalassemia. Bone Marrow Transplant. 2025;60:682–689. doi: 10.1038/s41409-025-02546-w
McCurdy SR, Solomon SR, Shaffer BC, et al. Post-transplant cyclophosphamide improves survival in HLA-DP1 mismatched unrelated donor allogeneic transplantation. Transplant Cell Ther. 2025, in press.

Advances in Treatment and Curative Options

Luspatercept (Reblozyl®)

This is an injectable therapy indicated for the treatment of anemia in patients with transfusion-dependent beta thalassemia. It binds several TGF-β superfamily ligands, which diminishes SMAD2/3 signaling and increases the production of mature red blood cells. It is administered every three weeks to help reduce anemia in patients requiring regular transfusions.

Mitapivat (Pyrukynd ®)

A small-molecule oral drug that activates a form of pyruvate kinase that is specific to red blood cells. The goal is to reduce ineffective erythropoiesis and improve anemia.

Betibeglogene autotemcel (Zynteglo ®)

This was the first gene therapy for thalassemia approved in the US by the FDA. It has not been submitted for approval in Canada and therefore is not available to Canadian patients at this time. This treatment uses a viral vector, which is a deactivated virus, to deliver a functional copy of the beta-globin gene to a patient’s own stem cells outside the body (ex-vivo)..Stem cells are collected from the patient, exposed to the viral vector to modify them by adding a copy of the beta-globin gene, and then returned to the patient. Once reinfused, these cells enable the production of normal or near-normal levels of adult hemoglobin, providing a functional cure of the underlying disease.

Exagamglogene autotemcel (Casgevy®)

This approach uses genome editing technology. The patient’s stem cells are removed through apheresis and then exposed to an electric current which allows the DNA strands to separate. Specialized “scissors” (CRISPR-Cas9) are used to edit the stem cells and deactivate the BCL11A gene, which normally suppresses fetal hemoglobin production. By switching off this gene, fetal hemoglobin production resumes, enabling the body to achieve normal or near-normal hemoglobin levels and, in many cases, transfusion independence and a functional cure.

From the fetal stage until about three months of age, humans naturally produce fetal hemoglobin, which has a high affinity for oxygen and allows efficient oxygen transfer from the mother to baby via the placenta. Beginning around three months of age, the BCL11A gene is expressed, which suppresses fetal hemoglobin and shifts production of adult hemoglobin. Adult hemoglobin has a slightly lower affinity for oxygen but more effectively delivers it to the body’s tissues.

Luspatercept (Reblozyl®)

This is an injectable therapy indicated for the treatment of anemia in patients with transfusion-dependent beta thalassemia. It binds several TGF-β superfamily ligands, which diminishes SMAD2/3 signaling and increases the production of mature red blood cells. It is administered every three weeks to help reduce anemia in patients requiring regular transfusions.

Mitapivat (Pyrukynd ®)

A small-molecule oral drug that activates a form of pyruvate kinase that is specific to red blood cells. The goal is to reduce ineffective erythropoiesis and improve anemia.

Betibeglogene autotemcel (Zynteglo ®)

This was the first gene therapy for thalassemia approved in the US by the FDA. It has not been submitted for approval in Canada and therefore is not available to Canadian patients at this time. This treatment uses a viral vector, which is a deactivated virus, to deliver a functional copy of the beta-globin gene to a patient’s own stem cells outside the body (ex-vivo)..Stem cells are collected from the patient, exposed to the viral vector to modify them by adding a copy of the beta-globin gene, and then returned to the patient. Once reinfused, these cells enable the production of normal or near-normal levels of adult hemoglobin, providing a functional cure of the underlying disease.

Exagamglogene autotemcel (Casgevy®)

This approach uses genome editing technology. The patient’s stem cells are removed through apheresis and then exposed to an electric current which allows the DNA strands to separate. Specialized “scissors” (CRISPR-Cas9) are used to edit the stem cells and deactivate the BCL11A gene, which normally suppresses fetal hemoglobin production. By switching off this gene, fetal hemoglobin production resumes, enabling the body to achieve normal or near-normal hemoglobin levels and, in many cases, transfusion independence and a functional cure.

From the fetal stage until about three months of age, humans naturally produce fetal hemoglobin, which has a high affinity for oxygen and allows efficient oxygen transfer from the mother to baby via the placenta. Beginning around three months of age, the BCL11A gene is expressed, which suppresses fetal hemoglobin and shifts production of adult hemoglobin. Adult hemoglobin has a slightly lower affinity for oxygen but more effectively delivers it to the body’s tissues.

Canadian Clinics & Hematologists

Find thalassemia treatment centers and hematologists across Canada who specialize in comprehensive thalassemia care.

For a comprehensive list of Canadian thalassemia clinics and specialists, visit: Canadian Hemoglobinopathy Association Locations

Medical Updates

Stay informed about the latest developments in thalassemia research, clinical trials, and treatment advances.

Clinical Trial Resources

Find clinical trials related to thalassemia in North America and internationally:

Clinical Trials Database (Health Canada)

The database is managed by Health Canada and provides a source of information about Canadian clinical trials involving human pharmaceutical and biological drugs. It contains a listing of specific information relating to phase I, II and III clinical trials in patients.

Visit Health Canada Clinical Trials Database

ClinicalTrials.gov (US Government)

A registry of federally and privately supported clinical trials conducted worldwide. It provides details on trial purpose, participant eligibility, locations, and contact information, to be used alongside advice from healthcare professionals.

Visit ClinicalTrials.gov

International Clinical Trials Search Portal

A search portal provided by the World Health Organization (WHO) can be used to access a central database that contains information about trials registered in several international registries.

Visit WHO Clinical Trials Portal