When it comes to diagnosing and treating diseases, one size does not fit all; patients with the same condition can have vastly different reactions to treatment.
The desire to unravel this medical mystery—why one patient responds to a therapy, or even recovers, while another does not—has made precision medicine a top research priority. A spotlight on this effort emerged in January 2015 after President Barack Obama announced the National Institutes of Health Precision Medicine Initiative (NIH PMI) to bring us closer to "the promise of precision medicine—delivering the right treatments, at the right time, every time, to the right person." Overall precision medicine aims to provide tailored healthcare as well as treatment strategies for diseases such as cancer, diabetes, and schizophrenia that are based on a person's general health, gender, ethnicity, environment, lifestyle, and biology.
But precision medicine is still in its infancy, and questions remain about the achievability of these goals. Here, Medscape details five key features of precision medicine.
The NIH PMI is the most ambitious precision medicine effort to date. Launched earlier this year with $215 million in funding, the PMI aims to accelerate innovations in biomedical research, technology, and therapeutics that provide individualized prevention and treatment options for patients. The initiative will initially focus on cancer but ultimately will expand to all diseases. According to NIH Director Francis S. Collins, MD, PhD, and National Cancer Institute Director Harold Varmus, MD, starting with cancer makes sense given that "[r]esearch has already revealed many of the molecular lesions that drive cancers" and shown that "each cancer has its own genomic signature." In fact, studies that pair specific patients with specific treatments are already underway. The large-scale MATCH (Molecular Analysis for Therapy Choice) trial, in particular, will sequence and classify thousands of solid tumors and lymphomas by their significant genetic mutations and target treatments to those abnormalities.
Early precision medicine endeavors have shown promise. First-generation precision medicine efforts involve decoding and grouping tumors by their genetic features, not by cancer type, explained Keith Flaherty, MD, director of developmental therapeutics at Massachusetts General Hospital Cancer Center in Boston. Researchers have already identified relevant mutations on BRAF, EGFR, and ALK to classify melanoma and lung cancer. And even before such gene-tumor matching, oncologists had uncovered the key molecular drivers of chronic myelogenous leukemia (CML) and gastrointestinal stromal tumors (GIST), and developed drugs to inhibit them—imatinib for CML and trametinib for GIST.
Despite the promise of precision medicine, right now we still have "imprecision medicine." Medicine today is still quite imprecise. Current estimates show that only 20% of patients benefit from the 20 most prescribed drugs, and 12 million serious diagnostic errors occur each year. Even basic screening modalities such as mammography and prostate-specific antigen tests yield a high rate of false positives. We have a long road ahead to make diagnosis and treatment more precise. That is why precision medicine can be viewed as a continuous process, a journey with no finish line.
Precision medicine initiatives raise concerns about patient privacy and security. Patients are at the heart of precision medicine. Precision medicine cannot move forward without thousands, even millions, of individuals sharing sensitive personal data. Ethical concerns have accompanied these plans to amass big data: How will these data be protected? Who will own the information? What should patient consent look like? Should doctors disclose potentially sensitive results to patients? In a recent article, Marilyn J. Hammer, PhD, DC, RN, reflected on a physician’s ethical obligation to tell patients when a test reveals a genetic variant with uncertain implications. Dr Hammer admitted that we don't have definitive ways to deal with such ambiguous situations, and that experts will need to visit and revisit these complex issues on a case-by-case basis as precision medicine science continues to evolve.
Precision medicine is not just about genetics. According to Dr Flaherty, the biggest misconception about precision medicine is that it centers on genomics. Although genetic information is a key aspect of understanding our health, precision medicine involves so much more—lifestyle, psychological well-being, biology, and ultimately how these factors intertwine. "The promise of precision medicine is that we will use every conceivable type of information about our patients to develop a therapeutic plan that is tailored to them and their vulnerabilities," said Dr Flaherty.
Medscape Oncology © 2016 WebMD, LLC
Any views expressed above are the author's own and do not necessarily reflect the views of WebMD or Medscape.
Cite this: 5 Things You Need to Know About Precision Medicine - Medscape - Sep 28, 2016.