Allogeneic stem cell transplantation for thalassemia major in India

Is Old (Fludrabine/Busulfan/Cyclophosphamide/rAntiThymocyteGlobulin) Conditioning Still Gold for Allogeneic Transplants in Transfusion Dependent Beta-Thalassemia of All Risk Categories in 21st Century?

Allogeneic stem cell transplant (allo-SCT) is the only curative option for transfusion dependent thalassemia (TDT) until the gene therapy could bring paradigm shift. We analysed TDT allo-SCTs performed with Flu/Bu/Cy/rATG conditioning between October 2018 and April 2022 at our center. A retrospective analysis of 55 consecutive HLA matched alloSCT for TDT and was approved by hospital's Institutional Review Board. Median age was 7(2-13) years. On presentation, number of patients with Class I, II, III were 18 (32.7%), 14(25.4%) and 23(41.8%) respectively {ClassIIIA = 14(25.4%),ClassIIIB = 9(16.3%)}. After downstaging, Class I, II, III were 22(40%), 15(27.2%) and 18(32.7%) patients respectively {ClassIIIA = 15(27.2%),ClassIIIB = 3(5.4%)}. Graft was bone marrow in 53(96.4%) and peripheral blood stem cell in 2(3.6%) patients. Mean CD34 stem cell dose was 3.28(1.2-6.5) × 106/kg. Neutrophils and platelets engrafted at a median of 16(12-32) and 17(12-48) days. Median duration of follow-up was 20.7(1.8-43.9) months. There was no primary rejection. Although, mixed chimerism was common {17(30.9%)}, there was only one secondary rejection (1.8%). Venoocclusive disease was seen 12(21.8%) patients {mild = 9(75%), moderate = 2(16.6%) and severe = 1(8.3%)}. Acute and Chronic graft versus host disease was observed in 4(7.2%) and 4(7.2%) patients respectively. There was no treatment related mortality. Overall survival and Thalassemia Free Survival were 100% ± 0% and 98% ± 2% respectively. Flu/Bu/Cy/rATG conditioning with BM graft is a safe and effective regimen even in higher risk. It also highlights the importance of pretransplant downstaging of risk class in improving the outcomes.

Economic burden of beta-thalassaemia major receiving hypertransfusion therapy at a public hospital in Mumbai

Background Treating beta-thalassaemia major may entail high costs with considerable out-of-pocket expenditure. Therefore, determination and valuation of the economic costs of a common haemoglobinopathy such as beta-thalassaemia major in India may provide insights to evolve policies for reduction or elimination of the disease. We estimated economic burden of beta-thalassaemia major in Mumbai in terms of cost to the family and the healthcare system. Methods This single-centre, prospective, cross-sectional, non-interventional study included children <12 years of age treated at the thalassaemia day care centre of a public hospital in Mumbai. The demographic data and treatment-related information was recorded. Cost of illness was studied from a societal perspective by the prevalence-based approach. Direct (medical and non-medical), indirect (loss of wages and loss of school days) and intangible costs (closed-ended iterative bidding) were calculated for each patient by interview. Results The total annual cost of treating 130 children with beta-thalassaemia major in Mumbai was ₹86 72 412 (US$ 127 535) or ₹66 710 (US$ 981) per patient per year and ₹12 82 30 412 (US$ 1 885 741) including intangible costs. Direct costs contributed to 94% of the cost of illness with chelation therapy (23%) and blood investigations (21%) being major contributors. Direct and indirect costs correlated significantly with duration of blood transfusion (p<0.05 and p=0.006, respectively), whereas indirect costs correlated with socioeconomic status (rho=0.25). Conclusion The majority (94%) of costs incurred by families for treatment of beta-thalassaemia major are direct costs, especially expenses for chelation and blood investigations. Even at subsidized rates, financial burden to the families from lower socioeconomic strata is likely to be considerable as these are out-of-pocket expenses. In consideration of the economic impact of treating beta-thalassaemia major in individual families, the healthcare system and society, it is prudent to promote and pursue long-term and short-term measures with urgent emphasis on prevention as a public health activity at the national level in India.

Thalassemia in India

Management and control of hemoglobinopathies are a challenge in India where 67.0% of people reside in rural regions. The GDP spent on health is one of the lowest (1.3%) resulting in high out-of-pocket expenses. The β-thalassemias are prevalent with an estimated 7500-12000 new births each year. Hb S (HBB: c.20A>T) and Hb E (HBB: c.79G>A) are also common regionally. Over 80 β-thalassemia (β-thal) mutations have been characterized in Indians. The δ gene mutations are increasingly being described and their coinheritance in β-thal carriers leads to a reduction in Hb A₂ levels and a misdiagnosis of carriers. Around 15-20 centers offer prenatal diagnosis (PND) mainly in urban regions. The projected annual cost of care of β-thal patients over a decade (2016-2026) will increase from INR30,000 (US$448) million to INR55,000 (US$820) million if all patients are adequately treated. Cost comparisons are difficult to make with other international studies as the standard of care, cost of medicines and other services vary in different countries. Several centers provide hematopoietic stem cell transplants (HSCTs) for thalassemias, however, only around 250 HSCTs are done annually. Although the cost is high, financial assistance is available for a few patients. There are disparities in the quality of care and to address this a National Policy has been proposed for the management and prevention of hemoglobinopathies that will embark on a comprehensive program, providing adequate care and augmenting the existing public health care services. It will also include training, genetic counseling and easier access to preventive options and a National Registry.

Recent Progress in Gene Therapy and Other Targeted Therapeutic Approaches for Beta Thalassemia

Beta-thalassemia is a genetic disorder characterized by the impaired synthesis of the betaglobin chain of adult hemoglobin. The disorder has a complex pathophysiology that affects multiple organ systems. The main complications of beta thalassemia are ineffective erythropoiesis, chronic hemolytic anemia and hemosiderosis-induced organ dysfunction. Regular blood transfusions are the main therapy for beta thalassemia major; however, this treatment can cause cardiac and hepatic hemosiderosis - the most common cause of death in these patients. This review focuses on unique future therapeutic interventions for thalassemia that reverse splenomegaly, reduce transfusion frequency, decrease iron toxicity in organs, and correct chronic anemia. The targeted effective protocols include hemoglobin fetal inducers, ineffective erythropoiesis correctors, antioxidants, vitamins, and natural products. Resveratrol is a new herbal therapeutic approach which serves as fetal Hb inducer in beta thalassemia. Hematopoietic stem cell transplantation (HSCT) is the only curative therapy for beta thalassemia major and is preferred over iron chelation and blood transfusion for ensuring long life in these patients. Meanwhile, several molecular therapies, such as ActRIIB/IgG1 Fc recombinant protein, have emerged to address complications of beta thalassemia or the adverse effects of current drugs. Regarding gene correction strategies, a phase III trial called HGB-207 (Northstar-2; NCT02906202) is evaluating the efficacy and safety of autologous cell transplantation with LentiGlobin. Advanced gene-editing approaches aim to cut DNA at a targeted site and convert HbF to HbA during infancy, such as the suppression of BCL11A (B cell lymphoma 11A), HPFH (hereditary persistence of fetal hemoglobin) and zinc-finger nucleases. Gene therapy is progressing rapidly, with multiple clinical trials being conducted in many countries and the promise of commercial products to be available in the near future.