An EU regulatory panel has recommended the approval of a gene therapy from GlaxoSmithKline (GSK) for the treatment of Bubble Boy Disease.
The Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA), together with the Committee for Advanced Therapies (CAT) issued a positive opinion last April 1 with regards to marketing the drug called Strimvelis for the treatment of ADA-SCID (Adenosine Deaminase Deficiency-Severe Combined Immunodeficiency).
"This positive opinion is a major milestone in GSK's commitment to the development of innovative, transformative medicines," says Martin Andrews, GSK's head of the Rare Disease Unit.
Lack Of Current Treatment Options For Bubble Boy Disease
At present, there is no approved medicine in Europe for Bubble Boy Disease. Although experts have tried to transplant blood-generating stem cells from the bone marrow of a healthy individual, success is uncertain as the procedure depends on how close the match between the donor and the patient is.
Patients whose stem cell donor is their genetically matched sibling usually have good rates of survival and recovery. However, those whose donors are unrelated to them typically have poor outcomes. This is because of the high risk of developing graft versus host disease, which is when the newly transplanted cells from the donor attack the cells of the recipient.
New Hope For Patients With Bubble Boy Disease
Now, patients without a matched donor are given new hope, thanks to GSK's new gene therapy.
Strimvelis is developed from a patient's young bone marrow cells, which will be injected with a normal adenosine deaminase enzyme gene. The resulting product will be injected back to the patient, after which, it will develop into various kinds of immune and blood cells. Experts anticipate that the procedure will result in the ability of the patient to produce lifelong lymphocytes, which is a white blood cell that fights off infection.
The procedure prevents graft versus host disease and reduces the dose of chemotherapy needed by the patient in preparation for treatment. Patients will also be freed from the burden of looking for a matched donor as the stem cells will come from the their own cells.
Clinical Study To Test Strimvelis
Strimvelis was tested in a clinical trial that involved 12 participants, who exhibited a 100 percent survival rate three years after the treatment. About 92 percent of the patients did not need any interventions such as enzyme replacement therapy to survive.
The typical side effects that the patients experienced include fever and various types of anemia.
More About Bubble Boy Disease
Bubble Boy Disease is a rare autoimmune disorder characterized by the presence of a faulty gene that halts the creation of adenosine deaminase, which disintegrates a toxic substance known as deoxyadenosine.
Patients who have this disorder generally cannot fight off infections effectively. This then leads to different growth and development problems, including liver and kidney impairments and deafness.
The clinical manifestations of Bubble Boy Disease typically surface when the patient reaches the sixth month of life. Patients with this disease usually succumb to death by the second year of life, unless of course the patient's immune system has been restored back to its normal function.