HEALTHCARE

Gene therapies show limited but growing use

Adam Cohen and Dr. Rod McEver

Special to The Oklahoman

The U.S. Food and Drug Administration has approved a number of gene therapies. They include treatments for several rare diseases, an inherited retinal disorder, relapsed or treatment-resistant leukemia and lymphoma, and, most recently, a form of hemophilia.

Adam’s Journal

I read about a clinical trial using gene therapy in a group of Alzheimer’s patients. I’ve heard the term a lot, but what, exactly, is gene therapy?

Dr. McEver Prescribes

Gene therapy modifies a person’s genes in an attempt to cure disease. It differs from traditional treatments because, rather than simply attempting to alleviate symptoms of an illness, it aims to fix the underlying cause of the disease.

The idea seemed theoretically enticing but was out of reach for many years, and it hit a major setback in 1999 when a teenager died in a clinical trial for gene therapy. However, further advances such as the 2012 discovery of CRISPR, a revolutionary technique for editing DNA, transformed gene therapy into a reality.

Since then, the U.S. Food and Drug Administration has approved a number of gene therapies. They include treatments for several rare diseases, an inherited retinal disorder, relapsed or treatment-resistant leukemia and lymphoma, and, most recently, a form of hemophilia.

Like all approved gene therapies, the clinical trial in Alzheimer’s involves a form of the disease caused by a specific genetic mutation. The treatment seeks to correct this flaw, which is present in roughly 2% of the population, by altering patients’ genetic makeup.

The trial is quite small and still in its early stages, but preliminary results announced this month indicate the treatment is safe. Data also showed promising signals the therapy could be effective, and the trial will now advance to the next stage.

Both for the Alzheimer’s trial and other illnesses, it’s important to understand that gene therapy is only possible if we pinpoint the specific genetic culprit for a disease. Unfortunately, for the vast majority of health problems — think heart disease, most cancers, and the lion’s share of Alzheimer’s cases — causation is much more complicated, or not yet fully understood.

At the Oklahoma Medical Research Foundation, scientists use the CRISPR gene-editing technique to create models of human disease in rodents and tiny fish. By continuing to probe the mysteries of DNA, we hope to develop new and innovative treatments that, like gene therapy, once seemed out of reach.

McEver, a physician-scientist, is vice president of research at the Oklahoma Medical Research Foundation. Cohen is a marathoner and OMRF’s senior vice president and general counsel. Submit your health questions for them to contact@omrf.org.