Virco Announces Development of ‘VirtualPhenotype’ Drug Resistance Test
Belgian genomics company Virco Group NV has developed a "quick test" to detect drug resistant strains of HIV in blood samples, the Wall Street Journal reports. The company reported Wednesday that the test is "just as accurate" as conventional resistance tests but "much faster," determining within 10 days whether patients harbor HIV strains that are resistant to particular HIV drugs. U.S. doctors currently determine drug resistance using two types of tests -- genotypic tests, which look at the genetic makeup of HIV strains to determine whether they contain "specific mutations" that have allowed them to become resistant to standard drugs; and phenotypic tests, which measure the viruses' ability to replicate when exposed to HIV drugs. Genotypic test results are "difficult to interpret" but are available within about 10 days, while phenotypic test results are more clear, but can take three to four weeks. Virco's "virtualPhenotype" test was developed by comparing viral genetic information from HIV-positive patients with a "large database" of HIV samples with "demonstrated sensitivity" to drugs. The virtualPhenotype test takes about as long as a genotypic test, but is "excellent at predicting clinical response," according to Neil Graham, vice president of clinical research at Virco. In addition, the Virco tests cost $450 each -- about half as much as the conventional phenotype test. The Journal reports that drug resistance has become a "major problem," with between 10% and 20% of HIV-positive individuals in the developed world developing resistance to "at least one drug, if not more" (Louis, Wall Street Journal, 2/8).This is part of the Morning Briefing, a summary of health policy coverage from major news organizations. Sign up for an email subscription.