One of the first ways personalized medicine is making its way into the clinic is through genetic testing for potential adverse drug reactions, Scientific American's Dina Fine Maron writes, but even that runs into issues with insurance coverage and interpreting results.
At St. Jude Children's Research Hospital, where insurance coverage isn't an issue as patient care is covered by grants and donations, clinicians are now routinely testing new patients for some 200 genes. For seven-year-old Korei Parker such genetic testing found that she breaks down the drug voriconazole too fast — she'd been prescribed that drug to ward off fungal infections that she was at risk for because of her severe acquired aplastic anemia. As Maron reports, Korei was then switched to a different drug.
While St. Jude and a handful of other hospitals offer pharmacogenetic testing, it often isn't covered by insurance, though Maron notes that is slowly staring to change. A spokesperson for a health insurance trade group tells her that coverage of these tests varies because of "limited clinical evidence around their effectiveness."
Further, doctors don't always think to order pharmacogenetic tests or know what to make of the results. Dan Roden, the assistant vice chancellor for personalized medicine at Vanderbilt University Medical Center, tells her that better prescribing roadmaps and guidance are needed to help support clinicians' decision making.
Mary Relling, chair of the pharmaceutical sciences department at St. Jude, adds that when doctors are better aware of the information such tests can provide, they'd likely become wary of prescribing drugs without having the tests done. "If you knew about this genetic information and you did not act on it," she says, "you would not be practicing good medicine."