There are many drugs out there that only work for a portion of patients, and personalized medicine approaches aim to direct patients to the drugs that will work for them. But, as the J. Craig Venter Institute's Nicholas Schork writes at Nature, standard clinical trials can't be used to test such personal interventions.
Instead, he says N-of-1 studies will become an important part of how personalized medicines are assessed, though such trials will need to be standardized. "Aggregated results of many N-of-1 trials (all carried out in the same way) will offer information about how to better treat subsets of the population or even the population at large," Schork adds.
For instance, he notes that an Australian study measured pain and other symptoms in some 130 osteoarthritis and chronic pain patients who took different drugs over the course of three years. Though expensive, Schork says this trial showed that formal N-of-1 trials could lead to more effective treatments being chosen.
However, he notes that there are stumbling blocks to making such types of trials more commonplace. Regulatory agencies, he adds, are hesitant to move away from classical clinical trials, and many drug companies would prefer their products to be able to be used by a wide portion of the population.
Still, Schork says governmental agencies and companies will come around, especially as interest in omic-based assays grows.
"A major advantage of the N-of-1 approach over classical trials is that patients are no longer guinea pigs, whose involvement in a study may help only future generations," he adds. "In N-of-1 trials, the effectiveness of different treatments [is] vetted for the actual participants."