Saturday, September 19, 2020

The unrealized potential of treating disease at a personal level - the mythos of personalized medicine

Photo by National Cancer Institute on Unsplash

Originally published at Medium in August 2020.

By Alicia M Prater, PhD (Aliconia Publishing) 

When I was a graduate student, my advisor would light up when explaining how our work was going to lead to personalized medicine. We were working on understanding the genetics underlying hypertension. The idea was that by knowing which gene polymorphism a person has, the doctor would know which class of drugs would have an effect on their blood pressure and correct the derangement.


The term itself, personalized medicine, implies the concept of treating each patient’s condition individually. Specifically, the concept is based on recognizing the specific genetic contribution the patient’s genome makes to their disease, though some researchers also aspire to a more holistic approach in which genes are just a part of the equation. This would presumably lead to earlier treatment with the most appropriate drugs, preventing unnecessary side effects and complications and resulting in a better prognosis.

However, more than 15 years later and, for most people, hypertension still requires a trial and error approach in order to find the right treatment. And it’s not the only disorder stuck in the impersonal and inefficient past. 

In 2007, JAMA published a commentary lauding the inevitable advances in personalized medicine after the completion of the Human Genome Project, quoting a researcher who summed up the aspirations behind this approach much more poetically than I:

“[G]enomics-based knowledge and tools promise the ability to approach each patient as the biological individual he or she is, thereby radically changing our paradigms and improving efficacy.”

The following year, a Nature journal noted that advances in understanding cancer and in treating tumors at the molecular level was ushering in the era of personalized medicine for cancer treatment. However, in 2017, 15 years out from the completion of the Human Genome Project, a review in Drug Target Review announced:

“[T]he new era of biomarker discovery for precision medicine in cancer begins now.”

Neither one was fully prophetic. Though we currently understand a lot more about the genes involved in tumor development and growth, and have even put some biomarkers into clinical practice, the field is far from achieving personalization for every type of cancer, or even for early detection.

Last year, the annual report on the approvals of personalized medicines by the FDA led to a headline that The Era of Personalized Medicine Has Arrived. Forty-two percent of new drugs approved by the agency in 2018 require a diagnostic test to determine treatment (their definition of a personalized medicine). Most were for cancer, and some were for genetic diseases that they pair with third-party genetic testing.

Where is the polymorphism evaluation for hypertension? Depression and other mental health disorders? Allergies? Alzheimer’s and other neurological and cognitive disorders? The biggest challenge cited by the Personalized Medicine Coalition in their 2018 report — money.

In addition to the research side of establishing the knowledge base and tools for personalized medicine, there’s another aspect to consider:

Harnessing the potential power of genomics in medicine requires physicians who can effectively use genetic tests and critically evaluate and interpret their results. The paucity of such physicians reflects the lack of sufficient education in genetics and genomics throughout medical training. -PLoS Med, 2009

Recognizing the issue means it can be fixed. But nearly a decade later, the era was still “coming”. In the last few years, some medical schools have added a certificate in personalized medicine to their MD tracks to address this shortcoming, and the AMA offers CME on the topic, but programs focusing on this field are still usually under the umbrella of genomics and genetics specializations.

And now the concept has been around long enough to have already undergone a shift in branding. The new moniker is precision medicine, with the emphasis on precision and excluding the personal. It’s about the genes, not you.

The concept of personalized medicine seems to come from a hope that we can be — and do — better. But for all the soothsaying and promises of the last 20 years, we aren’t even close to individualized medical treatment for most common disorders.

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