More and more “sewn” on the patient, with sartorial precision. Customized according to age, gender and clinical history. The new medicine is moving in this direction, opening up various questions about its sustainability but also giving much more hope in the treatment of diseases such as cancer, psoriasis, Parkinson’s disease, Alzheimer’s disease and asthma. An important component of this revolution has been the one derived from recent advances in genomics and related technologies, which allow to analyze in full the individual genetic heritage. These are technologies that in the last decade have seen enormous progress, including in terms of performance efficiency and cost reduction. Completing the first sequencing of the human genome has taken more than 10 years of work and about 3 billion dollars: currently it takes just one day to sequencing several, with a unit cost of less than 1,000 dollars. We talked about it with Professor Gioacchino Natoli, professor at Humanitas University and researcher in the area of advanced genomic technologies.
The role of genomics in new precision medicine
Genomics and related technologies have made it possible to analyze the entire individual genetic heritage. Today, the genomic analysis of the patient allows to quickly identify in his DNA mutated genes, which can be responsible for an ongoing disease and diagnostic for its recognition. Or it can indicate a predisposition, that is, a greater probability, compared to another subject who is not a carrier of it, to develop a given pathology. Or even offer indicators of the probable evolution of that disease and therefore of its prognosis. Finally, genomics gives predictive markers, i.e. useful to predict a greater or lesser ability to respond to a specific therapeutic treatment.
What is meant by personalized medicine?
“Good medicine” has always been tailored to the needs and medical history of the patient. So what’s new? What does the new precision medicine add today?
There is an urgent need – commented Professor Alberto Mantovani, Scientific Director of Humanitas – for independent and collaborative research, which is essential in order to be able to answer the complex and very transversal questions posed by the new approach, so that it will also be necessary to break, at least in part, the constraints of exclusivity of research carried out by pharmaceutical companies. Always without forgetting that in the end it is precisely the companies that develop and produce the new drugs, and they must also have a return”. Finally, what emerges is perhaps the most essential critical theme: “We need to think seriously about the concrete sustainability of a fascinating approach that is revealing how high its costs are. And the question that arises, then, is not only whether we are able to do precision medicine, but also whether we can afford it, and to what extent, since for the sake of fairness it should be accessible to all,” concludes Professor Mantovani. Therefore, doing precision medicine requires us to widen our gaze and grasp all points of view.
The case of oncology
Oncology has an important specificity that perhaps makes it different from all other areas of disease: here, in fact, it is the genetic characteristics of the tumor cell, and not those of the patient, that dictate in most cases the direction of therapy. In oncology, precision medicine has already led to some therapies that are often decisive: in addition to rituximab, examples include the small imatinib molecule for chronic myeloid leukemia, all-trans retinoic acid, or ATRA, for promyelocytic leukemia, the transtuzumab antibody for a type of breast cancer”. It is easy to understand how oncology, which was the first to succeed, was also the first to highlight difficulties, challenges of an increasingly precise medicine. “The fragmentation of the disease makes the clinical trial more complicated – Professor Mantovani points out – because the populations of patients enrolled in the studies must be selected with very precise characteristics, so they tend to be smaller and it becomes more difficult to reach a number of cases treated such as to provide sufficiently reliable answers on the effectiveness and safety of new drugs.
Until yesterday, classical medicine, especially in the research and application of new therapies, has constantly followed a population approach, favoring the magnitude of the average response in patients over the particular case, in order to assess the effectiveness of drugs in a statistically sound manner. This is where the approach of precision medicine comes into play, defined by Francis Collins, director of the National Institutes of Health, as “that set of prevention and treatment strategies that take into account individual variability”. It must therefore be a medicine that uses in-depth diagnostics and therapy in a hyper-specialized way, to package each individual patient in a specific way, but always accompanying the technical accuracy of the medical act with attention to the patient in its entirety: in essence, with customization.