New Rapid HIV, HCV Tests May Improve Point-of-Care Testing

Emma Hitt, PhD

August 19, 2011

August 19, 2011 (Atlanta, Georgia) ( UPDATED August 23, 2011 ) — A new HIV rapid test platform, designed to deliver test results in 10 minutes, may also detect HIV earlier in the course of infection than currently available rapid tests, new research findings suggest.

The new rapid HIV test is based on the existing OraQuick HIV rapid test platform. Findings regarding the test were presented by Lisa A. Kurtz, a senior scientist at OraSure Technologies, Inc, in Bethlehem, Pennsylvania, during an oral session at the 2011 National HIV Prevention Conference (NHPC) here. Researchers are also working on developing an oral hepatitis C virus (HCV) test.

Lisa A. Kurtz

The currently approved OraQuick ADVANCE Rapid HIV-1/2 Antibody Test detects antibodies to HIV-1 and HIV-2 in 20 minutes. The new test is designed to deliver results in 10 minutes.

The researchers evaluated the new test in commercial seroconversion panels (n = 24) and a worldwide serologic panel representing diverse genotypes (n = 15). Sensitivity was evaluated by using 169 samples derived from patients infected with HIV-2. Specificity was evaluated in 300 plasma and 500 whole-blood specimens.

Results from the tests were compared with those from a third-generation enzyme immunoassay (EIA). The rapid HIV test detected seroconversion within an average of 1.13 days of third-generation EIA (24 panels), which detects seroconversion 15 days before the Western blot.

The prototype assay was 100% concordant when tested in 169 HIV-2 samples. In addition, the new test was also concordant with EIA when tested with 15 worldwide serologic panel specimens detecting all major genotypes.

The test was also 100% specific in both plasma (300/300) and whole-blood (500/500) specimens.

"We will need to establish performance in larger-scale clinical trials in order to support [US Food and Drug Administration] approval," said Ron Ticho, senior vice president of corporate communications. "A key component of the regulatory approvals will also be obtaining a ‘CLIA [certificate of laboratory improvement amendment] waiver,’ which will allow the test to be used outside of laboratory settings, such as in doctor’s offices and clinics," he told Medscape Medical News.

According to Mr. Ticho, rapid tests provide actionable test results while the clinician still has access to the patient being tested. "This will improve linkage to care and prevents loss of patient follow-up."

Oral HCV Swab Test Under Evaluation

In another presentation at the same meeting, Jennifer Fuld, with the New York City Department of Health and Mental Hygiene, presented data on an oral swab rapid HCV antibody test developed by using the same OraQuick technology.

The finger stick version of the OraQuick HCV Rapid Antibody Test was approved on June 25, 2010, and is currently the only available HCV test that uses a finger stick. The current study evaluated the oral swab form of this test and found that overall, 97.5% of rapid test results matched those of the EIA. In 6 of the7 discordant pairs, the rapid test result agreed with the polymerase chain reaction result.

"From our experience in New York City, the rapid hepatitis C antibody test is ideal for high-risk community settings, and might make the difference for some patients between learning their status and not," said lead author Ann Drobnik, MPH, program collaboration and service integration analyst with the New York City Department of Health and Mental Hygiene.

"This is particularly true for those that have poor veins from injection drug use, or who have limited access to care and have difficultly attending multiple appointments and returning for their results," she told Medscape Medical News.

According to Ms. Drobnik, it is likely that the availability of the rapid test will increase the number of people willing to get tested for hepatitis C and the number of providers offering the test.

"It remains to be seen how rapid testing will impact testing services in practice and whether it results in many more people being tested, as the rapid HIV test did. The hepatitis C community is anticipating that testing will be more widely available and that many more people will learn their status," she said.

"Rapid tests for microbial diagnoses are evolving rapidly because of the need for faster results and advances in technology," said independent commentator John Bartlett, MD, professor with the Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland.

"A big advantage of the HIV test is the CLIA wavier, which means the [US Food and Drug Administration] does not require a lab technician, and the test requires no equipment," he told Medscape Medical News. "In fact, most of us think these tests will be sold in drugstores for use by consumers in the near future, just like pregnancy tests," he added.

According to Dr. Bartlett, for the new HIV test described here, there is a modest advantage in time and sensitivity. "It will be a useful addition if it compares favorably to the multiple HIV rapid tests now available in terms of sensitivity, specificity, and price," he added. "It does not meet an important unmet need because there are many such tests available, but it could emerge as the preferred test with these modest advantages."

"The HCV test appears to be a major advance," Dr. Bartlett continued. "As with HIV in 1996, most people who have HCV don't know it, and there are now great treatment options in rapid evolution," he said. "Therefore, there is the same urgency to find those with HCV and get them evaluated, just like there was (and still is) with HIV." According to Dr. Bartlett, the ability to do this with saliva instead of fingerstick blood is an advantage, but it needs to be shown that the saliva test is as good as the fingerstick test.

2011 National HIV Prevention Conference (NHPC): Abstracts 1351 and 1180. Presented August 16, 2011.

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