Often lauded as the future of medicine and a silver bullet to the spiralling costs of health care, private and public money is being poured into the research and development of precision medicine. In the United States, President Obama has pledged $215 million of funding in 2016 for the Precision Medicine Initiative, which he hopes will “bring (America) closer to curing diseases like cancer and diabetes – and give all of us access to the personalised information we need to keep ourselves and our families healthier”. But what is precision medicine? What advantages does it offer, and what are the challenges that must be overcome if precision medicine is to play a transformative role in the future of healthcare delivery?
Precision medicine is a new approach to disease prevention which focuses on a person’s individual factors, such as their genes, environment, and lifestyle. Today and throughout the course of history, disease treatment has generally followed a “one size fits all” approach, designed for the average person, without taking account of these unique factors. While this may be effective for the percentage of patients whose genetic makeup fits the average profile, many others with the same disease could react very differently to an identical medicine as a result of their own unique physiology.
Simply prescribing the exact same treatment across the board can result in inconsistent levels of efficacy, and for some patients, the development of negative side effects. Cancer, for example, is commonly treated with chemotherapy. Although often effective, chemotherapy is highly toxic and non-specific. Some cancers, such as rapidly dividing germ cell tumours, are extremely chemo-responsive. In the same way, some patients are more chemo-responsive than others. However chemotherapy can be wholly unsuitable for certain slow growing malignancies, where it would be more toxic than beneficial. When a patient is very unwell, chemotherapy may not be an option at all, as the side effects associated with the treatment would probably kill the patient before it reduced their disease.
Chemotherapy treatment sits at the very opposite end of the spectrum from precision medicine. Precision medicine involves breaking complex conditions down into smaller subtypes based specifically on their underlying causes, then targeting those causes at a molecular level.
There is one very successful example of a precision medicine for the treatment of cancer. In recent years, scientists have gained great understanding of how certain changes in DNA can cause normal bone marrow cells to become leukemia cells. The single protein which relates to a consistent chromosomal translocation that causes chronic myelogenous leukemia (CML) has been identified. CML is now treated with Gleevec, a drug that specifically targets this root cause at a cellular and sub-cellular level. Considered a “wonder drug” treatment, studies suggest that Gleevec is highly effective, boasting a success rate of 89%.
Admittedly, amongst cancer drugs, Gleevec is quite an exceptional case. While CML is caused by a single protein, many other cancers result from a multitude of complex interacting genetic and environmental factors, meaning one specific target cannot be identified. However precision medicine has a very important role to play in curing those cancers and other diseases which do have an identifiable cause.
Many challenges must be overcome before precision medicine will become mainstream, starting with the development of an efficient manufacturing supply chain. Current pharmaceutical manufacturing facilities are large scale, demanding high capital costs and churning out bulk quantities of the same product. This model means manufacturers are unable to reconfigure the production line for new products quickly, a setup which will not accommodate switching between production of small lots of a wide range of drugs, as the shift towards precision medicine would require.
The development of technologies that allow small batches of a diverse range of products to be manufactured economically, and distributed to the correct patients, will be critical. Flexible manufacturing facilities will be required to accommodate this technology, facilities that will look very different from the large scale plants of today. These facilities may in time be based on radical new technologies such as cell free expression, where recombinant proteins are produced in solution without the use of living cells, or even 3D bioprinting, the process of creating functional, viable cell patterns in a confined space using 3D printing technologies.
CPI is making strides towards bringing this new manufacturing approach to life with the opening of it’s Biologics Factory of the Future facility. The centre, due to be built in 2017, will provide organisations with the opportunity to develop and test precision medicine production technologies in a low risk, open access environment.
Another key hurdle to overcome is the regulatory framework currently underpinning precision medicine, which varies significantly between countries. For there to be a joined up global development and adoption programme, flexible solutions to regulatory compliance must be found, and a globally harmonised regulation system implemented.
A fundamental requirement of precision medicine is the large scale collection, analysis and understanding of multiple sources of patient data. This will need to be done in a way that protects patient confidentiality while extracting all of the necessary valuable data contained in an individual’s medical records. Collection and understanding of this data will be essential if personalised therapies and their associated diagnostics are to be developed.
The rise in biopharmaceutical technology has made it possible to better understand the genetic makeup of every individual. DNA sequencing enables doctors and medical researchers to determine, and in many cases understand, the molecular basis of a disease. An understanding at the molecular level makes it possible to break diseases down into subtypes, which brings about the opportunity to design treatments that are specific to each patient based on their individual need.
In the UK one in three people will develop cancer, incidences of diabetes are skyrocketing, and the population is aging rapidly. Although precision medicine is still in its infancy and the full scale of its impact is currently unclear, it is these diseases with clear genetic causes, such as certain cancer and autoimmune diseases, or complex lifestyle influences such as diabetes and aging, which it has the potential to treat.
As we advance our understanding of disease subtypes and match patients to a personalised treatment régime based upon the unique characteristics of the individual and their disease, patients will receive quicker, more effective treatment, with less side effects. By identifying diseases at an earlier stage, or even before they develop, precision medicine will eliminate both the need to take a trial and error approach to treatment and the associated resource wastage. This could achieve greater efficiency both in clinical trials and treatment, potentially saving the NHS, private health care providers and drug manufacturers significant amounts of money.
For these reasons, precision medicine is already surpassing the healthcare industry’s existing limitations. It is widely acknowledged that for continuous improvements in healthcare standards to be successfully delivered to a growing global population, the industry must shift towards preventative rather than reactive treatment. Precision medicine has the potential to play a key role in driving this much needed shift.