Gene therapy more effective and safer than HSCT in curing major beta-thalassemia

May 8, 2019June 6, 2019 Ask4healthcare

Gene therapy, a promising modality of treatment for major beta-thalassemia, is associated with fewer complications and hospital admissions over 2 years, than treatment by allogeneic hematopoietic stem cell transplantation (HSCT), a study conducted by Séverine Coquerelle and colleagues demonstrated.

Séverine Coquerelle, URC Eco-Assistance Publique Hôpitaux de Paris, Université Paris Diderot (Sorbonne Paris Cité), and CRESS, INSERM UMR (Paris), France, and his team of researchers analyzed the cost and effectiveness of gene therapy in comparison to allogenic HSCT as a curative.

Published as a paper entitled “Innovative Curative Treatment of Beta Thalassemia: Cost-Efficacy Analysis of Gene Therapy Versus Allogenic Hematopoietic Stem-Cell Transplantation,” the study revealed that patients treated with hematopoietic stem cell transplantation had 3 times more frequent infectious complications than patients treated with gene therapy, but the latter was shown to be about 2.8 times more expensive, with nearly half the expense of gene therapy accounted for by preparation of the delivery vector.

The comparative analysis was based on the data and outcomes of seven patients treated between 2009 and 2016, of which, four received gene therapy and three received hematopoietic stem cell transplantation (HSTC).

While comparing two-year costs and outcomes of patients treated with gene therapy and hematopoietic stem cell transplantation, the team looked at critical factors, such as length of hospital stay, interim hospitalizations, and grade III and grade IV complications.

Patients, who underwent gene therapy, despite being older, did not present with as many complications or hospitalizations as did those who underwent HSCT. Patients treated with HSCT suffered infections three times higher than those with gene therapy. While the gene therapy outcomes were comparatively more positive, the costs for this treatment were high.

The total costs estimates were based on hospital accounts and national cost studies. The team found that while gene therapy costs around 608,086 Euros, HSCT costs around 215,571 Euros. The high cost of gene therapy was mainly due to the procurement of the vector which accounted for 48% of the total costs.

The study results published in the journal Human Gene Therapy suggest that despite being costlier, gene therapy was not only more effective and safe but also less complicated as a treatment modality for major beta-thalassemia.

According to Human Gene Therapy Editor-in Chief Terence R. Flotte, MD, “There has been much discussion and controversy about the high cost of gene therapy, but what has been lacking is a direct comparison to alternative therapies, which themselves are also often very costly and may produce suboptimal outcomes. This study does a critical comparison of both cost and outcomes for patients with beta-thalassemia, whose primary alternative to gene therapy would be hematopoietic stem cell transplantation. These data may enable a more rational debate of the overall value of gene therapy for this relatively common genetic disease.”

There is no cure for beta-thalassemia, till date. It is caused by mutations in the HBB gene that provides instructions for making beta-globin protein. Beta-globin is a sub-unit of haemoglobin. A lack of beta globin leads to reduced amount of functional haemoglobin. Consequently, patients require lifelong regimen of regular blood transfusions. Even with treatment, there are many risks and co-morbidities associated with the disease such as iron overload in organs and the transmission of viruses through blood transfusions.

Allogeneic hematopoietic stem cell transplantation (HSCT) with a matched donor is the only available treatment, other than gene therapy, for this condition. But HSCT is a difficult process because nearly 75 percent of all thalassemia patients do not have an HLA (human leukocyte antigen)-matched sibling while finding an HLA-matched, unrelated donor from the bone marrow registries is also not too easy. Along with that, the success of the transplanted marrow depends greatly on age factor as well.

Gene therapy, on the other hand, is a safer option. It involves genetic manipulation of patient’s own cells to correct the genetic defect and later transplanting them back in the patient. Though gene therapy is costlier than hematopoietic stem cell transplantation (HSCT), it is comparatively less complicated.

To join thalassemia patient community, click here

To read this article in Hindi, click here