Beta-Thalassemia Patient Successfully Responds To Lentiviral Gene Therapy

A young adult with severe beta-thalassemia, an inherited blood disorder, has responded positively to gene therapy treatment, according to an article published in Nature. The patient, who had been dependent on regular blood transfusions since childhood, has not needed a transfusion for 21 months, or over two years since treatment with the LentiGlobin vector. The authors say he has had no adverse events (undesirable side effects).

The researchers say they also identified a subset of cells with the corrected beta-globin gene that overexpressed a truncated form of a gene called HMGA2. According to study data, the levels of the faulty gene that causes beta-Thalassemia has dropped, and continues falling.

Put simply – the patient suffers from an inherited illness that deprives his body of oxygen in the blood, caused by a faulty (mutated) gene. The scientists transferred a fully working version of the gene into his cells, to replace the faulty one.

Philippe Leboulch, M.D., senior author, head of the Institute of Emerging Diseases and Innovative Therapies of CEA and INSERM; professor of medicine, University of Paris; and visiting professor, Harvard Medical School, said:

Although based on the first treated patient, we believe these results are impressive and illustrate for the first time the significant potential for treatment of beta hemoglobinopathies using lentiviral beta-globin gene transfer in the context of autologous stem cell transplant. For beta-thalassemia, we have worked intensely for almost 20 years to design, develop and manufacture LentiGlobin to provide a sustained high level hemoglobin production, resulting in a major clinical benefit. It has been very rewarding to follow this patient as his life has dramatically improved since receiving our treatment.

Marina Cavazzana-Calvo, M.D., co-author, professor of hematology, University of Paris and chief of Cell and Gene Therapy Department, Necker-Enfants Malades Hospital in Paris. Salima Hacein-Bey-Abina, Ph.D., professor of immunology, University of Paris, added:

For the first time, a patient with severe beta-thalassemia is living without the need for transfusions over a sustained period of time. These results are not only world, but also represents a significant step forward for the field of autologous stem cell therapy as an emerging therapeutic modality.

The patient’s clinical hematologist, Dr. Françoise Bernaudin, who has followed the patient since he was a young child, said:

It is wonderful to see that this young man is for now free of transfusions and injections for iron chelation. He is happy to have a normal life back, and for the first time has a full-time job as a cook in a main restaurant in Paris. We are now even able to bleed him regularly to help remove toxic iron that had accumulated over the years because of blood transfusions.

Nick Leschly, president and CEO of Bluebird Bio, the developers of LentiGlobin gene therapy treatment, said:

We believe the human findings in beta-thalassemia, as well as the recently published data in ‘Science’ on two patients with childhood cerebral adrenoleukodystrophy (CCALD), highlight the significant opportunity for bluebird bio’s gene therapy platform to help patients with severe genetic disorders. We are committed to building a world-class company in gene therapy led by outstanding people as we move aggressively forward with multiple clinical studies, including our ongoing clinical trials for the development of LentiGlobin for beta-thalassemia and our product for CCALD.