Personalized medicine may be considered an extension of traditional approaches to understanding and treating disease. Physicians have always used observable evidence to make a diagnosis or prescribe a treatment tailored to each individual. In the modern conception of personalized medicine, the tools provided to the physician are more precise, probing not just the visually obvious, such as a tumor on a mammogram or the appearance of cells under a microscope, but the very molecular makeup of each patient.
A profile of a patient’s genetic variation can guide the selection of drugs or treatment protocols that minimize harmful side effects or ensure a more successful outcome. It can also indicate susceptibility to certain diseases before they become manifest, allowing the physician and patient to set out a plan for monitoring and prevention.
The ability to profile the structure, sequence, and expression levels of genes, proteins, and metabolites is redefining how we classify diseases and select treatments, allowing physicians to go beyond the one- size-fits-all model of medicine to make the most effective clinical decisions for each patient.
It is an approach that is well suited to the medical challenges faced in the 21st century. Although we have prevailed over many of the diseases that have plagued humanity throughout the ages, what remains are diseases of greater complexity: diabetes, cancer, heart disease, and Alzheimer’s disease. They are not caused by a single gene or a single event but by a combination of genetic and environmental factors, and they tend to be chronic, placing a heavy burden on the healthcare system. Personalized medicine provides the tools needed to better manage chronic diseases and treat them more effectively.
We can now point to real-world applications of almost every aspect of personalized medicine’s promise: Genetic profiles can better discern different subgroups of breast cancer, guiding physicians to select the best treatment protocol or, in some cases, forego the expense and risks of chemotherapy altogether; and tests detecting variation in the way individuals metabolize warfarin can help determine the right dose for a patient, navigating the narrow therapeutic passage between reducing risk of clots, and triggering internal bleeding.
Also, a test for mutations in the genetic coding for an enzyme can help physicians select the most effective drug for a colon cancer patient from an expanding pharmacopoeia of choices, avoiding a costly and protracted trial-and-error approach that can leave the patient suffering needlessly from adverse effects or losing precious time in battling the disease.
As evidence of the benefits continues to grow, an infrastructure of laws, policy, education, and clinical practice is building around personalized medicine to support its use:
- Medical institutions across the country have announced their commitment to putting personalized medicine into practice through dedicated centers or statewide initiatives.
- Personalized medicine approaches are becoming best practice in hospitals to ensure that patients with serious conditions such as cancer are given optimum therapy from the start.
- The regulatory system is integrating genetic testing into the labels of pharmaceutical products, ensuring that a drug is administered in a way that minimizes the risk of adverse effects and improves the chances of effective treatment.
- Nearly every major pharmaceutical development project is incorporating information on genetic variation and its effects on the safety and effectiveness of the candidate drug.
- Personalized medicine applications have extended beyond cancer to improve treatments in cardiovascular disease, infectious diseases, psychiatric disorders, and transplantation medicine.
- Several of the nation’s leading medical schools are launching genomics-based medical education programs to train the next generation of care providers.
- The American Association of Health Plans has advocated policy encouraging genetic testing and preventive care, while several large private insurers have begun paying for genetic tests identifying presymptomatic high-risk populations.
- The U.S. Department of Health and Human Services, the President’s Council of Advisors in Science and Technology, and the Personalized Medicine Coalition have defined wide-ranging policy recommendations for personalized medicine; a genetic privacy law has been passed, and other legislation supporting personalized medicine has been introduced in the U.S. Senate and House of Representatives.