You probably wouldn’t give your 80-year-old neighbour the same Christmas gift that you got for your 6-month-old nephew. But chances are, if they got sick with the same disease, they would be treated in more or less the same way.
This is because medicine as we currently know it generally relies on standards of care that is optimised for the “average” patient. This strategy leads to millions of people taking medication that wouldn’t necessarily be helpful to them. For example, statins, a very common class of drugs prescribed to lower cholesterol levels, is estimated to be effective only in <10% of patients. This means that the remaining 90% of patients are unnecessarily exposed to the side effects of this drug without reaping any of its benefits.
Personalised medicine, on the other hand, recognises that every person is unique, and that individual variations could be very important factors when it comes to treating diseases. Variations in the genome could render some individuals more responsive to certain drugs, or more tolerant to the side effects of some drugs. Having certain genes could also predispose someone to certain diseases (e.g. people with specific inherited mutations in genes called BRCA1 and BRCA2 are more likely to develop breast and ovarian cancers). With personalised medicine, patients are separated into different subgroups. The treatment plan is tailored for the individual patient based on the predicted response to the medication or their risk of disease. Thus, personalised healthcare results in a much more precise and efficient way to treat various diseases.
Left: All patients are treated with the same, standard therapy. Some may respond well to the treatment, but others may not.
Right: Patients with similar variations and characteristics are categorised into different groups. This targeted approach enables all patients to benefit from the treatment.
Image adapted from the DNA Research Center.
Since the completion of the Human Genome Project, more than 1,800 genes have been linked to specific diseases. Many genetic tests are now available for various conditions, and approximately 350 products are either approved or are currently undergoing clinical trials. A quick search of personalised cancer treatment in clinicaltrials.gov results in 317 studies.
In this series of articles, I hope to give you greater insights into some examples of personalised medications, explore current methods, and discuss the challenges facing the future of personalised medicine.