GSK's Gene Therapy Strimvelis Gains EU Approval with Money-Back Guarantee as One of the Most Expensive One-Time Treatments

Recently, the gene therapy Strimvelis, developed by Italian scientists and the British pharmaceutical giant GlaxoSmithKline (GSK), has been approved by the European Commission (EC) for the treatment of pediatric patients with adenosine deaminase-deficient severe combined immunodeficiency (ADA-SCID).

According to MIT Technology Review, GSK announced last week that the price of its Strimvelis therapy would be €594,000, making it one of the most expensive one-time treatments in history, and promised a refund if the treatment proved ineffective.

It is understood that ADA-SCID is a very rare disease. Newborns with this condition are unable to produce a specific type of white blood cell and lack a healthy, fully functional immune system, leaving them vulnerable to everyday infections and requiring them to live in sterile environments. It is estimated that approximately 15 cases are diagnosed annually in Europe. Unless these patients restore their immune function through matched bone marrow transplantation, they generally do not survive beyond two years of age.

Strimvelis gene therapy differs from previous treatments in that it offers a 100% cure rate through gene correction. It is the first commercially available gene therapy to achieve a lifelong cure by performing a one-time correction of the patient’s DNA.

Strimvelis therapy involves harvesting stem cells from the patient’s bone marrow, introducing a normal copy of the ADA gene into these stem cells via transduction, and then reinfusing the modified stem cells into the patient through intravenous infusion. Subsequently, a portion of the stem cells homing to the bone marrow. This therapy has been administered to 18 pediatric patients, with the earliest case treated 15 years ago. Currently, all 18 ADA-SCID patients who received Strimvelis treatment remain alive. A pivotal study demonstrated that the three-year survival rate for all pediatric ADA-SCID patients treated with Strimvelis was 100%. Strimvelis requires only a single administration and does not rely on third-party donors, thereby eliminating the risk of immune incompatibility due to rejection.

Currently, another treatment for ADA-SCID, bone marrow transplantation, costs approximately €900,000. The price of Strimvelis is two-thirds of that amount.

GSK stated that patients receiving its gene therapy would be enrolled in a registry for long-term follow-up, with a money-back guarantee provided if the treatment proves ineffective. Based on accumulated experience to date, GSK estimates the refund rate at approximately one in six. Additionally, GSK indicated that installment payment plans are available.

Reposted from: 36Kr