NEW YORK – A research study has shown that genetic testing to help guide medication decisions after a heart procedure is non-inferior to standard treatment.
Led by senior author Jurriën ten Berg of St. Antonius Hospital in Nieuwegein, the Netherlands, researchers conducting the POPular Genetics study compared a genotype-guided strategy of selecting anti-platelet medication to accompany primary percutaneous coronary intervention (PCI) with standard treatment of one of two platelet inhibitors.
They published their results today in the New England Journal of Medicine. First author Daniel Claassen also presented the study results today in Paris at the European Society of Cardiology Congress 2019.
The method to guide treatment soon after PCI is performed "resulted in less bleeding," Classens said in his presentation. "We demonstrated that genotyping is easy to use and you can get fast results."
The study used the Spartan Rx, a point-of-care, PCR-based, in vitro diagnostic testing system provided free to the investigators by Canada's Spartan Bioscience. St. Antonius Hospital also used the Thermo Fisher Scientific StepOnePlus Real-time PCR system.
PCI, previously known as angioplasty, is a procedure where a balloon is inserted into a blocked blood vessel and expanded to reduce blockage. Primary PCI is the urgent use of the procedure in people experiencing a heart attack.
Following Primary PCI, platelet inhibitors are often prescribed, along with aspirin. "Current guidelines favor the more potent platelet inhibitors ticagrelor and prasugrel over clopidogrel because these drugs are more effective for the prevention of thrombotic events," the authors wrote. "However, this greater efficacy comes with a higher risk of bleeding."
Approximately 30 percent of Caucasian patients have an "inadequate response to clopidogrel as measured with platelet-function tests," the authors noted, due to loss-of-function alleles in CYP2C19. "In patients without loss of function alleles, clopidogrel demonstrated similar efficacy compared to potent PY12 inhibitors," Claassens said.
Observational studies had previously suggested that CYP2C19 genetic testing could help guide medication decisions, but "it is unknown whether patients undergoing PCI benefit from genotype-guided selection of oral P2Ytk inhibitors," the authors wrote.
The researchers, based in the Netherlands, Belgium, and Italy, looked at net adverse clinical events after 12 months, including death from any cause, heart attack, stroke, and major bleeding, in 2,488 patients, with 1,242 in the genotype-guided group and 1,246 in the standard treatment group.
The researchers found the primary combined outcome — adverse events and major bleeding — were similar in the genotype-guided group (63 patients, or 5.1 percent) and the standard treatment group (73 patients, or 5.9 percent).
Additionally, Claassens said the genotype-guided study arm also experienced fewer minor bleeding events.