Precision medicine: Cutting through the complexity

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Precision medicine is reshaping health care by moving away from the traditional one-size-fits-all model to focus on treating each patient as a unique individual. Unlike broad categories, precision medicine can tailor treatments to the specific needs of individuals, aiming to find the right drug, for the right patient, at the right time.

The success of precision medicine, particularly in cancer treatment, where it is most advanced, lies in its detailed molecular characterization of disease states. This approach allows for a more accurate and personalized approach to diagnostics, prognostics and therapeutics. By understanding the unique genetic and molecular makeup of a patient, health care professionals can make more informed decisions about the most effective course of treatment.

Chen Xiong, PhD
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Precision medicine uses increasingly more detailed molecular characterization, such as DNA, of disease states to better identify and individualize diagnostics, prognostics and therapeutics. While this approach has introduced innovation for treating cancer, where its implementation is most advanced, it has also made the treatment landscape more complex and should be considered, to some extent, a work in progress.

The evolution of precision medicine

We have come a long way from the blunt tool of traditional chemotherapy as the primary cancer treatment. While chemotherapy drugs are effective, they are so because they kill rapidly dividing cells, including cancer cells, but they can also harm healthy cells, often leading to side effects. While chemotherapy remains vital to cancer treatment, precision medicine enables oncologists to more specifically target the underlying molecular drivers of cancer.

Advances in technology such as DNA sequencing and genetic testing have made it possible to identify rare genetic mutations and biomarkers associated with different cancer types. These biomarkers are measurable substances whose presence acts as an indicator for a disease state or provides insight into the nature of an illness. Clinicians use state-of-the-art diagnostic tools that provide data about the biomarkers of different cancer types for disease profiling.

Genetic and molecular profiling of tumors has become routine, allowing oncologists to identify specific genetic mutations or biomarker profiles. This has led to the development of numerous targeted therapies that are matched to the underlying disease profile, an approach that has paved the way for a new wave of cancer treatments and helps us understand why some cancer types respond to a treatment while others do not. Among the notable drugs developed through this approach is Herceptin (trastuzumab), which has been shown to be highly effective in treating breast cancer that shows a high presence of the human epidermal growth factor receptor 2 biomarker.

Precision approaches

Diseases may manifest differently in individuals, even if they appear similar externally—a factor precision medicine recognizes and addresses. This understanding emphasizes the need for precision treatment approaches. Once again, more advanced diagnostic methods used for precision medicine are employed here to better characterize the individual profile of a tumor.

Today, the forefront of precision medicine in oncology harnesses the body’s immune system to target and attack specific disease-related molecules or cells with a high degree of accuracy. This is known as chimeric antigen receptor (CAR)-T cell therapy. This technology involves genetically modifying a patient’s own white blood cells so that the cells recognize a specific drug target or biomarker that can be considered the antigen. CAR-T cells are then infused back into the patient to attack only the cancer. The effectiveness of this technology has been impressive and has led to increased survival rates in cancer patients. For example, a recent study of the CAR-T cell therapy Yescarta (axicabtagene ciloleucel) met its primary end point, with a complete metabolic response of 71% at three months versus 12% expected with standard of care. Additionally, the CAR-T cell therapy led to a 2.5-fold increase in patient survival after two years and did not experience cancer progression or require additional cancer treatment.

Benefits and challenges of targeted therapies

From the patient’s point of view, precision medicine offers a streamlined approach to health care, particularly when it comes to diagnostic testing. Instead of undergoing numerous tests, patients can benefit from comprehensive, all-in-one sequencing, resulting in quicker access to test results. This approach can cut down on trial-and-error treatments, giving patients greater confidence in the chosen treatment’s effectiveness and potentially reducing the need for multiple treatments and associated side effects.

While these health care advances may simplify the process for patients and lead to better outcomes in the form of better preventive care or more effective treatment, significant hurdles exist in making this a reality.

The challenge for the health care infrastructure is keeping up with the new advances in diagnostic tests and precision treatments, which can lead to treatment inertia. It takes time for health care professionals to learn about and become familiar with using new approaches, new technology or new treatments. Lack of access to new therapies or slow implementation may be further exacerbated for patient populations that may already see disparities in their access to the newest diagnostic approaches or treatments.

A further challenge to our health care model is how to best align the interests of various stakeholders, such as patients, doctors, health systems and payers. The aim is to ensure a more effective, efficient and economical use of new health care technology. Patients and physicians primarily focus on understanding and treating diseases, but the alignment between the pharmaceutical industry, insurers, distributors and payers is more complicated and needs to consider widely different perspectives and demands. Balancing these diverse interests in a cost-effective manner may be challenging, and more concerted efforts in reconciling these perspectives are worth exploring.

AI in precision medicine

The past number of years have seen a rapid evolution of precision medicine. Even more recently, artificial intelligence (AI) and machine learning (ML) have shown promise or success in a number of areas. There are signs of convergence between the fields of AI/ML and precision medicine, which will likely accelerate the goals of precision medicine and bring about further benefit to patients and health care systems across therapeutic indications.

While genome- and biomarker-guided prescribing has opened doors to precision medicines, turnaround times for these sequencing tests remain a major impediment to timely access to targeted therapies. Applying ML algorithms may potentially enable real-time treatment recommendations that can significantly expedite access and enable patients to experience the benefits of these effective therapies sooner. In addition, the ability for AI to generate large-scale predictive models that consider social determinants of health, comorbidities and clinical factors may be able to go further to identify new biomarkers that correlate to disease progression or improved patient outcomes. AI may also help us enhance patient stratification so that we can be more successful in not only identifying the right treatment for the right patient but also assessing the level of risk for various health conditions.

As breakthroughs in precision medicines aided by AI and technology continue to proliferate, being at the forefront of these developments becomes increasingly important for not just health providers but also biopharmaceutical companies seeking opportunities to develop novel life-changing therapies. Along with building in-house research and development capabilities, establishing the right thought partnerships with industry experts is becoming an essential element of spearheading innovation and successfully navigating the complexity that is precision medicine and the emergence of new treatment paradigms.

Chen Xiong, PhD, is a consultant with Lifescience Dynamics.