Doctors have long recognized that the outcomes from treating the same disease can vary widely from patient to patient. Wouldn’t it be wonderful if we could identify the factors that cause those differences and find a specific treatment that would work for each individual?
Enter Precision Medicine, which has now become front and center in achieving such a goal. It is generally defined as the finding of a specific treatment based on the individual characteristics of each person. But how realistic is it? Will we really be able to detect such differences and then develop a treatment that targets these characteristics and thus alter the course of a particular disease in a particular person?
In actuality, we have already seen the possible benefits of Precision Medicine, primarily in the area of cancer. For example, we have discovered that certain cancers are “driven” by specific mutations in the tumor’s genes and treatments have been developed that may be successful at interfering with those mechanisms. But can Precision Medicine do the same for other cancers, and other diseases, and for all patients? That is where it becomes difficult and in fact, there are several misperceptions regarding what Precision Medicine can do.
Misperceptions About Precision Medicine
First, the process of Precision Medicine does not mean the creation of a treatment, drug or medical device unique to every particular individual, but to find similar gene variations in a small subgroup of patients, to which a particular treatment can be applied effectively to all of them. Trying to find unique variants for each and every patient and then determining a treatment for each variant may be an unattainable task—trying to find a specific treatment for a particular subset of patients is much more likely to be successful.
Second, although Precision Medicine is based on variations in our genes, whether those genes become “expressed”—actually causes changes in our bodies—is not only based on the particular genes, but is also influenced by environmental and lifestyle factors, an area referred to as epigenetics. Precision Medicine must encompass each person’s epigenetic factors to have a benefit.
Currently, genetic testing is available for approximately 2,000 medical conditions. However, the ability to correlate that information with epigenetic factors and apply it to each person is only in its infancy. In fact, while some advances in Precision Medicine have been accomplished, the practice is not currently used for most diseases. In addition, along with some notable successes, there have also been notable failures. Just because a genetic variation and its epigenetic factors are identified does not mean a treatment developed for it will be effective.
Potential Therapeutic Areas for Precision Medicine
Cancer, which is the primary disease for which Precision Medicine has already been researched and utilized to some degree, serves as a good example. Specific mutations have been found in some cancer subtypes that have led to the development and application of chemotherapies that “target” that mutation and are successful in slowing that cancer’s growth and extending survival. On the other hand, many other mutations have been identified in tumors for which the treatments developed have not been very effective.
Besides cancer, the current emphasis of Precision Medicine is to focus on diseases such as Alzheimer’s, obesity, heart disease, diabetes and various mental illnesses. All of these diseases are very complex, with multiple genes and intertwining epigenetic factors determining a patient’s eventual outcome. Due to this, each of these diseases may need to be addressed using different approaches, many of which have not yet been developed.
When Will Precision Medicine Become Applicable?
It is also important to realize that to make Precision Medicine useful in treating diseases, it will require significant amounts of money, research and extensive collaboration among all medical providers. It may also change the way medicine is practiced and taught and how healthcare is provided to each person and how it is reimbursed to each medical provider. There will also be safety and privacy concerns and we will need a much more effective electronic health record system, which at present is too fragmented and not practical for the demands of Precision Medicine. It will also demand a significant change in how research is conducted, focusing on a more select group rather than an overall population. And all of this will take a lot of time to incorporate: Think in terms of a decade or even much longer, not in terms of years.
In the meantime, you should be cautious about many independent companies that are already jumping on the Precision Medicine bandwagon. They may tell you that they can test your genes and tell you what diseases you are predisposed to and sell you products to help prevent or treat those diseases. The vast majority of these tests have not been verified to be accurate nor have studies been conducted to prove that the products will actually help you prevent or treat these diseases. The result may be a waste of your time and money.
Precision Medicine holds great potential but has significant challenges before it can be used effectively. It won’t happen overnight and there will be many failures along the way. However, it is a starting point and is a worthwhile endeavor, as long as we are cautious and understand the numerous impacts and implications it will have for our future healthcare system.