Precision medicine: tremendous promise, but more than a few challenges
The very name is redolent of the aspiration of countless healthcare providers and patients to have access to diagnoses and treatments that can identify, treat and eliminate diseases with pin-prick accuracy.
But how realistic is that goal, or, put another way, how many challenges stand in the way of being confident that our medical tools might soon be considered “precise”? According to three Harvard researchers, quite a few.
In a recent blog at Health Affairs, Jonathan Darrow, Aaron Kesselheim and Jessica Lasky-Su, two professors at Harvard Medical School and a genetic researcher, respectively, begin by noting the great fanfare and expectation with which efforts to advance precision medicine have been unveiled and received. From President Obama’s announcement of the Precision Medicine Initiative (PMI) in his 2015 State of the Union Address, to the launch of the “Cancer Moonshot” in the same address last year, to the recent passage of the 21st Century Cures Act, the wind is certainly in the sails of an array of efforts to put data collection and analytics systems to work understanding the precise cause of, and cure for, diseases as they manifest themselves in particular patients.
Despite the resources and hopes being invested, however, the writers suggest that caution is in order, especially when it comes to expecting how quickly these efforts will translate into results.
“While scientific knowledge relevant to precision medicine has increased substantially in recent years,” they observe, “translating these findings into the clinic to truly transform patient care remains difficult. Considerable time and further research will be necessary to effectively utilize these findings in a clinical setting. In the case of cancer, varying genetic abnormalities within different regions of the same tumor . . . mean that even a breakthrough therapy that is 100 percent effective in targeting a particular genetic defect may fail to cure the entirety of the condition. More broadly, the considerable genetic heterogeneity that exists within the US population will also complicate the characterization of patient groups for which new treatment approaches are efficacious.”
In addition, they point to the numerous stakeholders who argue that “focusing too strongly on technology and research detracts from more basic determinants of population health, such as socioeconomic or geographic disparities, environmental improvements (e.g., clean water), or other factors that have little to do with genetics but may lead to far more measurable improvements in public health.”
Still, their caution notwithstanding, the writers fall largely into line with the enthusiasts for precision medicine, pointing out that “the social and scientific context of the PMI and Cancer Moonshot are substantially different from when,” for example, President Richard Nixon declared War on Cancer back in 1971. Numerous fundamentals of genetics were still not understood, for instance, and the Human Genome Project had yet to be created, let alone reduce the cost of whole genome sequencing from tens of millions of dollars to around $1,000 per genome today .
Moreover, perhaps most broadly, “the rapid development of computer and laboratory technologies has also transformed the context of the PMI. Nearly a half century of advances according to Moore’s law means that computers have orders of magnitude more processing power than they did when Nixon was in office, providing the power to analyze the prodigious volumes of data generated from DNA sequence analysis or electronic patient health records.”
So what does all this add up to? Perhaps just a needed corrective to the inevitable hype that political leaders and other advocates rely on to call attention to their ideas and early successes.
As for the bottom line, according to three front-line stakeholders, anyway, “For all its faults, precision medicine holds more promise now than it ever has.”