NEW YORK (GenomeWeb) – Within a large pharmacogenetic study ongoing at several Indiana institutions, researchers are aiming to tackle the issues that have kept personalized medicine approaches from reaching disadvantaged communities.
Earlier this month, Eskenazi Health, the Indiana Institute for Personalized Medicine (IIPM), the Indiana University School of Medicine, and the Regenstrief Institute announced the launch of a 6,000-patient prospective trial to study the impact of preemptive pharmacogenetic testing in a community healthcare setting.
Top academic and medical centers across the country have launched similar PGx testing programs, but many people in the US don't have access to these state-of-the-art facilities. Under the leadership of David Flockhart, director of the IIPM, and Paul Dexter, chief medical information officer at Eskenazi Health, the aim of the so called INGenious trial will be to deliver personalized medicine to those who have limited access to such innovative tools and strategies in medical care.
Eskenazi Health, the largest healthcare system in Indiana, places a special focus on the underserved population in Marion County. Between its hospital and 10 community health centers, Eskenazi Health sees around 1 million outpatient visits and 15,000 adult admissions each year.
Within this patient population, 45 percent are uninsured, 26 percent are on Medicaid, and 18 percent are Medicare patients. According to the US Census Bureau, 21 percent of the county's population is in poverty, which exceeds the 15.8 percent poverty rate for all of Indiana, and the median household income is $42,000, well below the $48,000 median household income for the state.
"We can't just say, 'Oh, drive in from 50 miles away, or even drive in from 10 miles away,'" Flockhart told GenomeWeb. "How are they going to pay for the bus? How are they going to pay of the cab?" INGenious is one of the projects funded under NIH's $11 million Implementing Genomics in Practice program.
Literacy and language pose additional barriers when trying to gain patient consent for medical procedures involving molecular diagnostics and difficult genetics concepts. Of the more than 900,000 Marion County residents, 12 percent speak a language other than English at home and 27 percent have a Bachelor's degree or higher. At the nation's top academic centers, where personalized medicine and genetic testing approaches are more commonly implemented, the patient community tends to be more educated, Flockhart noted. But within Marion County, his team is "dealing with a population where the word gene has to be explained on a below middle-school level."
As such, INGenious — in which researchers plan to include 4,000 subjects as controls and 2,000 patients who will receive treatments guided by pharmacogenetic testing results — will involve coordinators who "understand [the] literacy problem and the financial situation." Given that close to 10 percent of Marion County's population is Hispanic or Latino, some of the education will be in Spanish. Additionally, patients who are traveling to get to the study site will receive financial aid.
Some of the seven sites involved in the study will be responsible for communicating to patients about the influence that genetics can have on drug response, a topic they are unlikely to have heard much about before. Flockhart noted that the goal will be to explain to patients in "simple terms" that the effectiveness of their treatments and the related side effects can in part be influenced by the genes they inherited from their parents. But the research staff won't necessarily have to explain pharmacogenetics concepts face-to-face to all 6,000 participants, since only 2,000 will be getting tested, Flockhart noted.
So far, investigators have enrolled a few hundred people into INGenious. The patients in the PGx testing and control arms will be matched according to the some 33 medications that are of interest in the trial.
Because the field of pharmacogenetics is advancing so fast, Flockhart's group decided to implement a custom microarray and flexible study design so they could keep up the state of the science. "If a new discovery comes up and a new genetic variation influences the effect of aspirin or something, we have the ability to very quickly put that variant on our chip and put it into our information systems," Flockhart said.
His team has a weekly meeting to discuss any new PGx markers from the literature that might be of importance to the study. Researchers have so far settled on testing patients for 51 SNPs in 16 genes shown in the literature to be associated with response to the 33 drugs. The test data will be recorded in patients' electronic health records and in Eskenazi's clinical decision support system so doctors can have the genotype results handy at the time they are prescribing medications.
PGx testing will be offered in the outpatient and emergency room setting, with the ultimate goal of assessing whether such an intervention improves the health of patients seen at Eskenazi Health and reduces costs over a year. "There will be an overall answer for whether PGx testing saves money in the big picture," Flockhart said. "But then, using our informatics system, we can see if the emergency room was losing money hand over fist or if the GI clinic is making money. From a healthcare administrator's point of view, we can get fairly granular."
Data from INGenious might even provide an economic argument in favor of or against implementing PGx testing in controversial settings, such as in the context of dosing warfarin. Variations in CYP2C9 and VKORC1 genes account for around 10 percent and 30 percent, respectively, of the differences seen in patients' responses to standard doses of warfarin. Since patients tend to metabolize warfarin at different rates, the incorrect dose can lead to life-threatening hemorrhages.
An analysis of medical claims for atrial fibrillation patients who received warfarin between January 2003 and December 2007 found that the cost per patient with warfarin-related intracranial bleeding was nearly $42,000 and more than $40,000 for each patient with a major gastrointestinal bleed. However, studies to date haven't definitely convinced the medical field as to whether PGx testing in this context improves patients' outcomes in terms of bleeding risk and hospitalizations.
"With things like warfarin, where huge costs are involved, we'll be able to answer questions" as to whether PGx testing is useful, Flockhart said.
INGenious is slated for completion in June 2018.