GSK’s ‘Bubble Boy’ Gene Therapy Pushed Forward by EU Drug Agency
Remember, last month we told you about GlaxosmithKline’s (GSK) Strimvelis –‘Bubble Boy’ Gene Therapy. Well, it has taken another leap towards becoming the first personalized gene therapy for the treatment of extremely rare congenital disorder ‘Bubble Boy Syndrome’.
The European Union’s (EU) drug regulator backed up Strimvelis which was recommended for approval by Committee for Medicinal Products for Human Use (CHMP) of European Medicines Agency (EMA) for the treatment of ‘Bubble Boy Syndrome’. The approval was based on the Strimvelis’ pivotal clinical trial results which demonstrated 100% survival rate of the patients after an average of seven years follow-up time. Its approval in Europe would unlock the access to this investigational personalized gene therapy for the worldwide patients. Strimvelis was developed by GSK with its Italian research partner San Raffaele Telethon Institute for Gene Therapy and Milanese medical biotech company, MolMed.
Bubble Boy Syndrome commonly known as Adenosine Deaminase Deficiency-Severe Combined Immunodeficiency (ADA-SCID) is a rare genetic disorder in infants which makes them unable to fight off everyday infections and they become prone to severe fungal, viral and bacterial infections which ultimately can turn fatal for them.
GSK’s Strimvelis is an ex-vivo gene therapy in which a copy of missing ADA gene is inserted into faulty stem cells of patient by a virus vector and the body’s capability of producing its own ADA gene is evoked leading to the production of ADA enzyme in the body which is responsible for the production of healthy lymphocytes, finally functionalizing immune system in the body.
Figure 1. Mechanism of action of gene inserted by virus vector in gene therapy (Photo credit: Gene Therapy Wikipedia)
According to Martin Andrews, Head of GSK’s rare diseases unit, although the prevalence of ADA-SCID is low but approximately 120-300 ADA-SCID cases arise every year and GSK’s Strimvelis could benefit eight out of ten patients who are unable to find their matching donor for bone marrow transplant.
“I can tell you it’s been very expensive to invest in this over the last six years,” Andrews said. “But actually we expect to spread the benefits across other medicines in GSK’s portfolio. By having a portfolio approach and by applying it to increasingly larger diseases, even though they may still be rare, it does become economically viable”.
Strimvelis is a one-time stem cell therapy which makes it more affordable alternative to weekly enzyme replacement injections. According to a Bloomberg analysis, Strimvelis could reach 67.5 million pounds sales in 2020.This technology platform could further be utilized to support other gene therapies in the pipeline of GSK including the oncology therapies.
Featured image credit: European Flags In Brussels © Jorisvo (Stock Photo ID: 24966080)