Precision medicine for complex chronic diseases: how near are we?

Targeting medicines against the genetic and molecular drivers of lung, breast and other tumours has helped transform cancer care for many patients, yet precision medicine for complex chronic diseases has lagged behind. Maria Orr, Adam Platt and Ben Challis, from BioPharmaceuticals R&D at AstraZeneca, explain why this is changing for chronic diseases.

PRECISION MEDICINES combine information about an individual’s unique biology, matching the right treatment to the right person at the right time of their disease to improve patient outcomes. Since the completion of the Human Genome Project in 2003, significant progress in understanding the genetic and molecular drivers of diseases has led to the design of precision medicines that specifically target underlying disease mechanisms. Alongside these treatment advances, diagnostics have been developed that identify biomarkers in tissues and body fluids that can be used to predict a patient’s likely response to a medicine.

To date, the delivery of precision medicines and their associated companion and complementary diagnostics has been largely in the treatment of cancer, with researchers targeting the underlying causal biology including individual driver mutations. So why is it taking longer to apply a similar approach for chronic diseases?

The challenges of complexity

Digging deep into the biology of chronic diseases to uncover genetic and molecular drivers has guided the identification of new biomarkers and the development of linked precision diagnostic tests for novel, targeted therapies”

The simple answer is that treating chronic diseases, such as heart failure and chronic obstructive pulmonary disease (COPD), is more complex than targeting a single mechanism that may be a driver of a given tumour type. Common chronic diseases can be driven by multiple genetic and molecular defects, many still unrecognised or not fully understood, combined with environmental factors to cause a range of disease-producing mechanisms. Furthermore, by their nature, chronic diseases progress over time and often present differently between patients depending on other aspects of their health. Researchers are therefore not only looking for the proverbial needle in a haystack, but for multiple needles in a continually changing haystack.