Director’s Corner

May 16, 2019: Examining Precision Medicine Through a Rare Diseases Lens

Christopher Austin

For millennia, physicians have diagnosed human ailments by categorizing symptoms and then treating patients according to these preformed categories. While this approach has been enormously valuable in allowing health care providers to effectively identify, understand and manage many diseases, every doctor knows that each patient’s disease is unique in presentation, course and response to treatment.

This has led to endless good-natured sparring among physicians who either emphasize what is common among patients’ illnesses—the “lumpers”—or emphasize what is different—the “splitters.” Over the last several decades, the splitters have gained more ground as a result of dramatic improvements in gene sequencing, imaging and environmental monitoring, among other technologies. The approach of characterizing and treating each person’s disease as unique has come to be called “personalized” or “precision” medicine. Cancer immunotherapy illustrates the possibilities for precision medicine, and NIH is leading a variety of efforts to catalyze progress in this field. One year ago last week, NIH launched the 1 million-person All of Us Research Program to catalyze progress in this field.

I was privileged last month to take part in a meeting of the Pontifical Academy of Sciences at the Vatican in Rome that considered issues in precision medicine. Like translational science, the meeting brought together people from fields that know nothing of each other. I found it eye-opening and enormously productive. My contribution to the meeting’s deliberations focused on a point I have made here before: Rare diseases teach us much about both the promise and potential perils of precision medicine.

In many ways, the translational science principles and approaches NCATS has been applying to the development of rare diseases treatments are also a roadmap. A rare disease affects less than 200,000 people in the United States, and a personal disease occurs at the individual level. Chances are you know someone with a rare disease—there are about 7,000 different rare diseases that affect an estimated 30 million Americans. This is more than twice the number of people living with cancer and more than the number of people living with HIV and Alzheimer’s disease combined.

Through research, collaboration and patient engagement, the rare diseases research field is paving the way to precision medicine’s vision of using individualized data to match patients to therapies. Paradoxically, rare disease research also has led to community efforts to share data, establish interoperable registries and identify commonalities that would benefit all.

Precision medicine, like every new approach for disease prevention and treatment, has potential downsides in application, and the meeting delegates focused on this. There were, to my surprise, significant concerns as to whether the pursuit of precision medicine would decrease enthusiasm or support for population-level public health interventions that have historically resulted in the greatest improvements in health, such as access to clean drinking water, adequate nutrition and vaccination. The delegates agreed that the benefits could be realized without the risks, but only if both are proactively considered and managed.

Advances in rare disease diagnosis, treatment development and care exemplify that a scientific, data-driven approach and ongoing stakeholder engagement—including, most importantly, patients and communities—can deliver enormous benefits and mitigate the harms, if not entirely eliminate them.

In 1657, the physician William Harvey, who first discovered that blood circulates in the body, said that “[there is no] better way to advance the proper practice of medicine than to give our minds to the discovery of the usual law of nature by careful investigation of cases of rarer forms of disease.” Precision medicine shows us again that William Harvey was right.

Christopher P. Austin, M.D.
National Center for Advancing Translational Sciences