DES PLAINES, Ill., July 17 /PRNewswire-FirstCall/ -- Since the first diagnostic test for the human immunodeficiency virus (HIV) came on the market in 1985, public health authorities have been concerned about HIV's ability to mutate and create new strains of subtypes that may elude detection. While many of the variant strains of HIV are not as prevalent in the United States as other countries, studies suggest that the influx of immigrants from countries where these strains are more common is increasing the number of newly diagnosed patients infected with variant HIV-1. If gone undetected, these variant strains of HIV could compromise treatment.
According to some studies, these infections, found mainly in immigrant populations from Africa and Asia, may represent up to 10 percent of HIV-1 infections in certain areas of the United States.
With the U.S. launch of Abbott's RealTime HIV-1 viral load test, a highly sensitive test designed to detect and precisely measure group M, N and O strains of HIV-1 as well as all known group M non-B subtypes, physicians now have a reliable, precise test to help ensure that their patients are receiving the most effective treatment.
The test, marketed through Abbott's alliance with Celera, has been developed for use on Abbott's automated molecular diagnostics m2000(TM) system, based on real-time polymerase chain reaction (PCR) technology. The test is intended for use as a marker of disease prognosis and as an aid in assessing viral response to antiretroviral treatment. Both the RealTime HIV-1 assay and the m2000 system are being showcased at the annual meeting of the American Association for Clinical Chemistry (AACC) in San Diego, July 15-19.
"With the increasing prevalence of HIV-1 non-B subtypes in the United States and other countries, it is critically important to have a reliable and accurate viral load test to monitor treatment efficacy and implement preventive measures for our increasingly diverse patient populations," said Linqi Zhang, Ph.D., associate professor and staff investigator, Aaron Diamond AIDS Research Center. "Abbott has developed an assay with these considerations in mind, which will undoubtedly facilitate better treatment in both the developed and developing world."
HIV-1 can be divided into groups M (major), O (outlier) and N (new). The vast majority of isolates cluster in the M group, but the high mutation rate and rapid evolution of the virus has resulted in the emergence of different group M subtypes, designated A through K, and circulating recombinant forms.
A study by Dr. Zhang and his colleagues, focusing on the genetic characterization of HIV-1 strains circulating in immigrant populations in New York City, indicates that multiple subtypes of HIV-1 are present in these populations. The results of the study were published in the Journal of Acquired Immune Deficiency Syndrome in 2006. "It is generally assumed that infections in the United States are exclusively with the B (subtype) and that this situation is going to continue into the foreseeable future," the authors wrote. "This study shows that this is unlikely to be the case and that non-B subtype strains already have a strong presence in the United States and have the potential for spreading in the future."
In another study by the Centers for Disease Control and Prevention earlier this year involving more than 3,000 HIV patients at 409 sites from 11 states, 5.1 percent of those patients were infected with HIV-1 non-B subtypes or a recombinant form (subtype C accounting for 2 percent and CRF02_AG accounting for 1.4 percent). The study demonstrated that the range of non-B subtypes and recombinant forms across the regions was 0 to 10.8 percent.
"Successful monitoring of people on HIV drug therapy mandates use of viral load assays to effectively identify and quantify all variant HIV-1 subtypes," said John Robinson, Ph.D., senior director, research and development, Abbott Molecular. "The reliability and precision of the Abbott RealTime HIV-1 test on the m2000 system for detecting HIV-1 subtypes across a broad dynamic range should help physicians be confident about assessing viral levels in their patients, enabling them to provide optimal treatment."
About the Abbott RealTime HIV-1 Test
The RealTime HIV-1 assay is among the most sensitive viral load tests available today, with a broad dynamic range capable of quantitating HIV-1 in plasma down to as few as 40 RNA copies per milliliter (mL) and up to as many as 10 million copies per mL. Also, unlike other assays, the Abbott RealTime HIV-1 test targets the highly conserved pol integrase region of HIV-1 and has demonstrated the ability to detect diverse group M subtypes as well as group N and O isolates. Quantitative measurements of HIV-1 levels in blood have greatly contributed to the understanding of the process by which the virus infection leads to disease and has been shown to be an essential parameter in prognosis and management of HIV infected individuals. Decisions regarding initiation or changes in antiretroviral therapy are guided by monitoring plasma HIV-1 levels or viral load, CD4-T cell count, and the patient's clinical condition. The goal of antiretroviral therapy is to reduce the virus in plasma to below detectable levels.
The RealTime test is intended for use in conjunction with clinical presentation and other laboratory markers as an indicator of disease prognosis and for use as an aid in assessing viral response to antiretroviral treatment as measured by changes in plasma HIV-1 RNA levels. The assay is not intended to be used as a donor-screening test for HIV-1 or as a diagnostic test to confirm the presence of HIV-1 infection.
About the Abbott m2000 Instrument System
The Abbott RealTime HIV-1 test runs on the new Abbott m2000, an automated system that uses real-time polymerase chain reaction (PCR) to amplify, detect and measure minute levels of virus in blood samples as well as extremely high levels of these infectious agents. Real-time PCR enables the production of large quantities of DNA from very small samples in a short period of time, making it possible to detect extremely low levels of a virus's genetic material. The Abbott m2000 system automates the important steps of the process, from sample preparation to data analysis, allowing laboratories to process molecular tests efficiently, accurately and confidently.
The m2000 system can help molecular laboratories increase efficiency and reduce the time it takes to deliver test results, thereby helping physicians improve medical care through earlier intervention and the ongoing monitoring of a patient's response to therapy. It also reduces the manual procedures and hands-on time required to prepare patient samples for DNA/RNA testing by as much as 75 percent.
In addition to having a best-in-class assay for HIV-1, Abbott's m2000 system is faster than competitive systems, delivering 96 test results in less than five hours for HIV-1 as compared to up to two days for other systems.
About Abbott's Molecular Diagnostics Business
Abbott Molecular, a division of Abbott based in Des Plaines, Ill., is an emerging leader in molecular diagnostics -- the analysis of DNA, RNA and proteins at the molecular level. Abbott Molecular's instruments and tests provide physicians with critical information based on the early detection of pathogens and subtle, but key changes in patients' genes and chromosomes. They help physicians diagnose disease and infections earlier, select appropriate therapies and monitor disease progression.
In addition to the RealTime HIV-1 viral load test and the Abbott m2000, Abbott Molecular's portfolio of products also includes innovative genomic tests for chromosome changes associated with congenital disorders and cancer, including the PathVysion(R) HER-2 DNA Probe Kit, a test used to help select women with breast cancer who could benefit from Herceptin(R) therapy, and UroVysion(TM), which detects genetic changes in bladder cells for aiding in the diagnosis of bladder cancer in patients with hematuria (blood in the urine) and for monitoring bladder cancer recurrence.
About Abbott
Abbott is a global, broad-based health care company devoted to the discovery, development, manufacture and marketing of pharmaceuticals and medical products, including nutritionals, devices and diagnostics. The company employs 65,000 people and markets its products in more than 130 countries.
Abbott's news releases and other information are available at the company's Web site at http://www.abbott.com.
AbbottCONTACT: Media, Don Braakman, +1-847-772-3263, or +1-224-361-7246, orFinancial, Tina Ventura, +1-847-935-9390, both of Abbott
Web site: http://www.abbott.com/
