Individualized/Precision medicine is a rapidly emerging novel approach to practicing health care and represents the next wave in medicine. In Individualized medicine, the patient’s specific information is used to achieve greater diagnostic precision, to identify and execute better-tuned and more effective therapeutic regimes, and, eventually, to achieve speedier and longer-lasting recovery. By virtue of taking into account the patient’s unique clinical, social, genetic, genomic, and environmental information, Individualized Medicine can allow most accurate predictions about a person’s susceptibility to developing disease, the course of disease progression, and the expected response to a given therapy, and thus can be uniquely-tailored to each patient.
Genomic and individualized medicine aims to tackle non-contagious diseases, such as cancer, heart disease, and diabetes, which are thought to be driven by environmental factors and the interaction of these factors with the human genome. It is now understood that because these diseases have strong multi-gene components—and in some cases might be caused by errors in the DNA betweengenes (intergenic DNA) instead of within genes (intragenic DNA)—they can be better understood using a whole-genome approach.
The advanced technologies that are available today make it increasingly possible to link defects in the molecular machinery of cells and tissues to the development of specific diseases. As a result, we now have the ability to identify mutations in an individual patient’s tumor and use that information to select cancer therapies that are most-precisely targeted at these cancer-causing mutations. These discoveries are helping us transcend the age of one-size-fits-all cancer care and usher in the more desirable and exciting era of individualized disease treatment. Cataloguing and understanding the molecular defects underlying a given disease can also help identify individuals or populations who may be at increased risk of developing the disease, thereby enabling a preemptive approach to disease prevention.
This new era of molecularly-based medicine is the culmination of many successes in basic, laboratory, and applied research. The progress represents a clear-cut example of the significant return-on-investment that can be brought about by long-term funding of such research.
Specific advantages that individualized medicine may offer patients and clinicians include:
- an ability to make better-informed medical decisions (administer the right treatment, to the right patient, at the right dose for the right extent of time)
- an expected increase in the response rates, progression-free survival and overall survival thanks to better-tuned and more targeted therapies
- a reduced probability of negative side effects (drugs that are more effective but less-harmful)
- earlier disease intervention than has been previously possible
- molecularly based drug design (targeted therapy)
The key task is to identify disordered or activated transcripts (both non-coding and protein-coding) and genetic variations that play a pivotal role in a disease. The first step is to associate the occurrence of a particular transcript (protein, gene variant, or non-coding transcript) with the incidence of a particular disease or disease predisposition. Such a guilty-by-association approach can lead to results that may vary from one individual to the next and depend on many factors including environmental circumstances. The outcome is the development of biomarkers, which are robust and predictive.
Molecular biomarkers may correlate with specific clinical aspects of a disease and represent a new paradigm for designing and developing more effective and less harmful therapies, what is commonly known as “targeted drugs” or “targeted therapeutics.” Further, these biomarkers are having an impact on all aspects of cancer care including prevention, early detection, diagnosis, treatment, and drug development. As a result, we are now beginning to understand why, for example, two patients who share a common clinical diagnosis, e.g. Non-Small Cell Lung Cancer, may actually represent two very different diseases at the molecular level, thus requiring two entirely different types of therapy.
A prerequisite for practicing individualized medicine is an infrastructure that provides speedy access to suitably annotated biological specimens derived from tissue, cells, or blood and provided on the basis of informed donor consent. Detailed and extensive clinical information is also necessary based on patient medical records or clinical trial data. Once such a repository is available, basic and applied research can begin. In this context, successful research activities require a very high level of collaboration among scientists and physicians from varying disciplines that work together to make sense of all the data and distill actionable information from it.
Some early successes that are the outcome of exploratory work using carefully selected patient cohorts come from the hematology/oncology clinical setting. For example measurements of ErbB2 protein in breast, EGFR mutations in lung, and RASmutations in colorectal cancer have to be looked at carefully before picking the per-case proper targeted therapy. Another example pertains to acute myeloid leukemia (AML) patients with normal karyotype. In such cases, FLT3, NPM1 and CEBPa molecular testing is taken into account in order for the physician to decide whether allogeneic transplantation is the proper course of action.
It is conceivable that in the not-so-distant future, tissue-derived molecular information will be combined with an individual’s personal medical history, family history, and data from imaging, and other laboratory tests to develop more effective treatments for a wider variety of conditions.
The sequencing of the human genome in the early years of the 21st century provided crucial insights into the biological workings underlying countless medical conditions. As a result, scientists and physicians are advancing the field of individualized medicine at a fast pace. Even though it is not yet an established part of clinical practice, a number of top-tier medical institutions have established individualized medicine programs with some actively conducting already both basic research and clinical studies in genomic medicine.