October 30, 2011
Genetic Testing Could Result In Personalized Cancer Treatment
Advances in DNA testing could open the door for more expensive cancer treatments to be approved, as well as more personalized treatment options to emerge, one expert told Telegraph Medical Correspondent Stephen Adams on Saturday.
Matthew Seymour, director of the National Cancer Research Network (NCRN), told Adams that genetic testing techniques were advancing so rapidly that doctors could soon administer such an exam to find out which types of medicine would work best for them. That, in turn, could encourage regulators to approve costly treatment options, even if they only prove most effective on a handful of patients.
"New drugs are often turned down by the National Institute for Health and Clinical Excellence (NICE), because trials show that -- on average -- they only enable patients with advanced cancer to live a few weeks longer," Adams wrote, noting that NICE opted not to approve Avastin for bowel cancer because "trials showed it only prolonged life by six weeks on average."
Some, however, "lived much longer" thanks to the drug, he added. If medical experts could pinpoint which people would benefit most from medications like Avastin, Seymour says, it could lead to what Adams calls "smart prescriptions" individualized to each patent's genetic disposition.
"What we are finding is that most people get no benefit, or are even harmed, by new drugs. But we are finding that some receive great benefit," Seymour, a professor of gastrointestinal cancer medicine at Leeds University, said. "We have to get clever about how to target drugs. Medications for cancer have to be personalized because no two cancers are identical."
"Most drugs companies now understand that their world has changed, and if they don't introduce personalized medicine, they are simply not going to get their drugs approved and purchased," he added.
According to Adams, a study conducted by Seymour illustrates the point. A trial of a chemotherapy drug called panitumumab revealed that it did not "significantly benefit" patients. However, it was later learned that as two out of every five people carried a specific gene mutation that kept them from benefitting from the drug, and further work pinpointed the group of cancer patients who benefitted most from the medication, many of whom lived "significantly longer" because of the drug.
The results of the study, which was sponsored by Cancer Research UK, will be presented during the National Cancer Reseach Institute conference next month, the Telegraph reported, and it marks the first time that genetic testing had been joined directly with a bowel cancer trial.
"This heralds a new generation of clinical research," Seymour said. "When we have got drugs that only benefit a small number of patients, it is really important to find out who it is that is going to benefit“¦ The idea of treating 100 patients and only a few benefiting is ludicrous. We shouldn't be doing it anymore."
On the Net:
- National Cancer Research Network (NCRN)
- National Institute for Health and Clinical Excellence (NICE)
- Cancer Research UK
- National Cancer Reseach Institute