Clinical trial demonstrated value of genetic point-of-care testing and a rapid time to result
Here’s a milestone in genetic testing that should catch the attention of pathologists and clinical laboratory managers everywhere. It is a point-of-care (POC) genetic test that is reliable enough to be used in a clinical trial.
The clinical trial was called RAPID GENE. It was conducted at the University of Ottawa Heart Institute (UOHI). The study enrolled 200 patients who were being treated with cardiac stenting for an acute coronary syndrome or stable angina. What made this study unique is that—for the first time in medicine—it used a point-of-care (POC) genetic test. The genetic POCT was used to overcome many previous obstacles that had prevented use of more routine clinical genetic testing.
About half of the patients in this clinical trial were randomly selected to undergo the bedside genetic testing. The genetic test featured a saliva swab test performed at a patient’s bedside by clinical nurses with no prior training in genetic laboratory techniques, but who had been given 30 minutes of instruction on how to use the POC device.
This was followed by a one-step insertion of those swabs into a testing machine and, within 60 minutes, there was an answer as to whether any of the tested individuals carried the at-risk genetic variant: CYP2C19*2. Genetic testing to gain this kind of patient knowledge using existing diagnostic technology can typically take between five to seven days to return results to the referring physician.
The clinical trial was designed to identify how patients with the at-risk genetic variant, CYP2C19*2, compared to the group of patients who had no genetic testing when administered conventional clopidogrel (Plavix) treatment given following the stent procedure. Patients with the at-risk genetic variant were administered an alternative drug, prasugrel (Effient) which protected them from adverse events. The value of a rapid genetic test for these patients lies in the fact that most complications for a CYP2C19 carrier undergoing this procedure occur in the first 24 to 48 hours. It often takes several days for results to come back when specimens are sent to a central clinical laboratory.
Study Physicians Say POC Genetic Testing Is Accurate
Physicians who conducted the study were apparently delighted at the reliability and convenience of the point-of-care genetic test. According to Derek Y.F. So, M.D., FRCPC, M.Sc., the study’s lead researcher, “These results are extremely promising, not only in the field of cardiology but for all areas of medicine. If you can administer a simple, rapid genetic test at the bedside, doctors can prescribe the right drug to the right patient at the right time. We then have a much greater chance of improving health outcomes and providing cost savings for the health care system.”
Dr. So is also staff cardiologist at the UOHI and assistant professor in the Department of Medicine at the University of Ottawa. The clinical trial findings were presented on November 10 by Dr. So at the Transcatheter Cardiovascular Therapeutics 2011 conference—the world’s largest forum for interventional cardiovascular medicine and a showcase for the latest advances in current therapies and clinical research.
“The RAPID GENE trial shows that point-of-care genetic testing is clinically feasible and accurate, and facilitates rapid personalization of anti-platelet therapy. A pharmacogenetic approach to treatment carries the potential to maximize treatment efficacy, while simultaneously minimizing harm to patients,” said Jason D. Roberts, M.D., the Rapid Gene study’s director.
The POCT test was developed by Spartan Bioscience Inc. of Ottawa, Ontario, Canada. The system is called the Spartan RX CYP2C19. In the RAPID GENE study, Spartan Biosciences stated that “The test had a sensitivity of 100% and a specificity of 99.4% compared with DNA sequencing.” The Spartan RX CYP2C19 testing system cannot be sold in the United States.
For pathologists and medical laboratory administrators, the RAPID GENE study demonstrates how two important healthcare trends will be intertwined going forward. The RAPID GENE trial was designed to explore how genetic variations in patients may affect their individual responses to therapeutic drugs. The use of an innovative point-of-care genetic test shows how technology advances in clinical diagnostics will make it possible to move many medical laboratory assays out of the central clinical laboratory and into POC and near-patient settings.