Precision Medicine – what is it, and what does it mean in Clinical Research?

Every day, millions of people take drugs that are not helping them. This is due to missing knowledge on the specific individual effects of certain substances.

The realization that doctors need to include this individual variability in their considerations leads to an increasing interest in what is known as “precision medicine”. In January 2015, US president Barrack Obama announced a „Precision Medicine Initiative“, that would establish a national database of genetic and other health-related data of millions of US citizens. (Schork, 2015)
So what exactly is „precision medicine“? Jameson and Longo (2015) define „precision medicine“ as treatments that are tailored to an individual patient‘s particular needs, based on biomarkers, genetic, phenotypical and psycho-social characteristics that differentiate one patient from another with similar symptoms.
What does this personalized approach mean for clinical trials? Clinical trials are routinely based on the assessment of a few parameters from numerous patients. The discovery of a treatment that is effective in a certain subgroup is rare and often an incidental finding. Often, these incidental findings are the result of a disappointing outcome of a large study where researchers investigate why the treatment worked in some subjects while not in others. This approach is inefficient and costly.

One alternative are studies that focus on a single individual, known as N-of-1 studies, in which all kinds of clinical relevant data are obtained from one person.When sufficient data is collected over a long enough period of time and the appropriate control groups are used, it is safe to say whether a particular test person has responded to a treatment or not. The aggregated results of many N-of-1 studies that were all carried out under the same conditions provide information that may lead to better treatment for sub-groups of the population, if not the entire population. (Schork, 2015)
Conclusion: Well-designed, sophisticated N-of-1 trials should contribute to classical clinical trials confirming the efficacy of tailored treatment. In line, adequate biomarkers, monitoring devices, study designs and data analyses need to be developed.