Gene therapy aims to fix a faulty gene or replace it with a healthy gene to try to cure disease or make the body better able to fight disease. It holds promise as a treatment for a wide range of diseases, including cancer, heart disease, diabetes, and inherited disease such as hemophilia and cystic fibrosis.
The FDA has approved gene therapy products for several conditions, including cancer, spinal muscular atrophy, hemophilia and sickle cell disease. However, for most people, gene therapy remains available only as part of a clinical trial.
A gene can’t easily be inserted directly into your cells in the body. Rather, it usually is delivered using a carrier called a vector. The most common gene therapy vectors are viruses. That’s because they can recognize certain cells and carry genetic material into the genes of those cells. Viruses can be modified and deliver a gene needed to stop disease. Viruses aren’t the only vectors that can be used to carry changed genes into your body’s cells. Other vectors being studied in clinical trials include stem cells and liposomes.
Gene therapy is a promising treatment and a growing area of research. But its clinical use is limited today, and several major barriers stand in the way of some types of gene therapy becoming a reliable form of treatment, including finding a reliable way to get genetic material into cells, targeting the correct cells or gene, and lowering the risk of side effects. Mayo Clinic provides a handy overview of FDA-approved gene therapy products.