About Gene Therapy

Each person inherits features from his or her parents in the form of genes, which are made up of a molecule called DNA. Genetic diseases, which involve a problem with the functioning copy of the gene, may be corrected by gene therapy. Gene therapy is intended to provide a functioning copy of the gene to make up for the genetic defect.

A key challenge for gene therapy success has been to efficiently and safely transfer a functioning copy of a gene into a patient’s cells. Improvements in these transfer vehicles, including lentiviral vectors, have been made in recent years.

More than 1,800 clinical trials have been conducted using different types of gene therapy in various diseases. In 2011, approximately 70 clinical trials evaluated different types of gene therapy for a variety of diseases, including cancers, blood diseases, central nervous system disorders and immune system diseases.

An investigational gene therapy using a lentiviral vector was previously used in a clinical study in France to treat four boys with CALD. As of March 2013, the disease stopped progressing in three of the four boys. None of the four have experienced serious, unexpected side effects from the investigational gene therapy treatment. However, not all short- and long-term risks are known at this time, and all patients continue to be followed by their doctors.

Patients enrolled in the Starbeam Study are being followed by their doctors at this time. Data from this study is not yet available.