Wednesday, October 13, 2010

Stratified Medicine: The Dawn of a New Era in Medicine

For the most part, medicine has been deployed on a "one type fits all" mentality to prevent/treat disease. There are of course exceptions and provisos to this. The age or relative health of a patient is often taken into consideration when deciding which course of treatment will be the most safe and effective for a particular patient. A person's medical history (e.g. adverse reactions to a particular treatment, allergies) or lifestyle (e.g. smoker) is also relevant to determining which specific treatment is best for a patient. But beyond those kinds of considerations, prescribing X to treat person Y was based on the evidence that X has proven to be an effective treatment for other people suffering the same thing that afflicts person Y.

But the genetic revolution has opened up a new door of "personalized medicine" that permits doctors to tailor treatments to their patients based on knowledge about their specific biology. And so X might be prescribed for person Y because it has proven to be a safe and effective treatment for a group of people who share the same specific genetic mutations that person Y has. This could increase the safety and efficacy of medical treatment.

Nature@news has this interesting story about how the UK unveiled plans this week to utilize broad genetic testing for selected cancer patients. As the story notes, "this form of 'stratified medicine' uses genetic information to group patients according to their likely response to a particular treatment". A sample from the story:

....The tests, which will look for several dozen mutations in about a dozen genes linked to cancer, will be carried out on people with lung, breast, colorectal, prostate or ovarian cancers, or metastatic melanoma, who are being treated at six NHS hospitals. Therapies that target specific tumour-causing mutations have already been approved, or are on the verge of approval, for most of these conditions, says Peach.

....Peach hopes that the first phase of the cancer programme will pave the way for expanding genetic testing to more patients and other conditions, such as diabetes, AIDS and even psychiatric disorders. Cancer offers a good testing ground for personalized medicine, because numerous targeted therapies already exist, but "there's no reason why this should be restricted to cancer", says Peach.