Although scientists have long understood that most rare diseases are caused by harmful genetic mutations, it often takes several years for doctors to identify which gene is causing a patient’s specific symptoms. These years take a toll on patients and their families, who watch loved ones suffer despite dozens of costly tests and visits to various doctors and specialists. Even after the disease is diagnosed, existing daily maintenance medications can sometimes prove woefully inadequate.
Fortunately, new tests and therapies emerging in an era of personalized medicine are helping physicians use diagnostics to determine which medical treatments will work best for each patient.
A new technology called next-generation sequencing (NGS) can test for thousands of genetic mutations at one time. Scientists hope NGS tests may someday replace the battery of single-gene tests that doctors often use to understand the potential causes of a patient’s symptoms. The use of NGS tests may help shorten the diagnostic odysseys that many rare disease patients must endure before receiving an accurate diagnosis, thereby reducing associated expenses and improving patients’ lives.
Meanwhile, to improve the prospects for patients with rare diseases after they are diagnosed, the biopharmaceutical industry is developing an emerging group of personalized medicines known as gene therapies. Gene therapies promise to deliver lasting benefits by reversing the genetic causes of diseases. The U.S. Food and Drug Administration approved the first gene therapy, called Luxturna (voretigene neparvovec), in 2017. By revising a harmful genetic mutation, Luxturna can restore vision to patients with Leber congenital amaurosis, a rare genetic retinal disease.
Researchers studying the benefits of NGS tests, gene therapies and other personalized treatments hope that their work will help advance a new era in health care that quickly targets more effective treatments to patients who will benefit from them.