Hi-tech medicine, boon or bane?

Hi-tech medicine, boon or bane?

During the past several decades, treatment for a variety of conditions has begun to shift from a “one size fits all” approach to a more personalised strategy. As a result, patients can more often be matched to the best drug for their genetic makeup or the exact subcategory of their disease. This enables physicians to avoid prescribing a medication (or a dosage) that might cause serious side effects in certain populations. In other words, even among patients who apparently have the same disease and symptoms, the treatment for each one would be determined by various predictive or prognostic tests. But, while this high-tech approach could be a boon to patients, it could prove detrimental to drug companies’ bottom lines. The reasons are subtle. Personalised drug therapy uses biological indicators, or “biomarkers” — such as DNA sequences or the presence or absence of drug receptors — as an indicator of how patients should be treated, as well as to estimate the likelihood that the intervention will be effective. This concept is not new: it has been known for decades, for example, that people who have a genetic deficiency of an enzyme called G6PD can experience severe and precipitous anemia if they are exposed to certain drugs. Improving the efficacy and reducing the side effects of drug therapy will be a boon to doctors, patients, and insurance companies, to be sure, but why should pharmaceutical companies embrace personalised medicine in the long term? On the positive side, in any kind of experiment, a fundamental principle is that the greater the number of subjects or iterations, the greater the confidence in the study’s results. Unless the effect of the intervention is profound, small studies generally have large uncertainties in results. That is where biomarkers can help drug makers to design clinical studies that will show a high “relative treatment difference” between the drug and whatever it is being compared to. In reality, however, the situation is more complex. Assessments of safety and efficacy often do not move closely in tandem, so that even if smaller, better-targeted clinical trials offer clear evidence of a drug’s efficacy, regulators might demand far larger studies to provide evidence of the drug’s safety. Thus, the impact of personalised medicine in the short term might be positive at the patient’s bedside, but vast clinical trials to demonstrate the safety of new drugs will impose huge development costs that manufacturers might never recover. If society is to derive the maximum benefit from personalised medicine — which will require companies to pursue it — regulators worldwide will need to adopt reasoned and reasonable policies. Henry Miller is a physician and molecular biologist