The polymerase chain reaction (PCR), long a tried-and-true tool in the research setting, is increasingly the basis for clinical tests aimed at improving disease diagnostic and prognostic capabilities, monitoring disease progression, and, increasingly, predicting drug response and adverse reaction or toxicity risk.
Recent PCR-based product development announcements and presentations at scientific meetings highlight the growing role this technology is playing in the translation of biological, physiological, and pharmacological information from the laboratory to the clinic.
Continuing technology improvements are contributing to the development of robust and easy-to-perform PCR-based assays that are moving toward point-of-care applications. For example, Spartan Bioscience recently received CE IVD Mark approval for its RX CYP2C19 in vitro diagnostic test, a point-of-care system designed to test a buccal swab sample for the presence of the *2 variant of the cytochrome P450 2C19 gene.
Patients carrying this gene variant—which is present in about 30% of the population—have a reduced capacity to metabolize the anticoagulant drug clopidogrel (Plavix®) into its active metabolite.
Spartan reports that carriers of the gene who receive a standard dose of Plavix following insertion of a cardiac stent to open a blocked artery have a 42% higher risk of death, stroke, or heart attack during the first year compared to noncarriers. The test can help guide drug treatment decisions.
Larry D’Andrea, CEO of Spartan, describes the Spartan RX as a “sample-to-result” testing platform that is 100% sensitive and specific. A buccal swab sample is placed directly in a tube, which is loaded into the device. The PCR-based test determines the presence of the *2 variant and can indicate whether the patient is homozygous or heterozygous at the CYP2C19 locus.