New 4th generation HIV assays now available to improve screening for HIV infection

Laboratory Corporation of America^® Holdings (LabCorp^®) (NYSE: LH) announced today the availability of a 4^th generation HIV antigen/antibody combination assay and a new diagnostic algorithm that improves screening for HIV infection.

Earlier detection of HIV can improve individual treatment and help reduce the spread of HIV in the population. New 4^th generation HIV assays have the ability to detect both the HIV antibodies (IgG and IgM) and the HIV p24 antigen simultaneously prior to seroconversion. On average, the 4^th generation assay allows for detection of HIV seven days earlier in acutely infected individuals than would be possible with 3^rd generation assays. These assays are an important enhancement to LabCorp's test menu, which encompasses the most comprehensive, cost-effective diagnostic products available to provide physicians and their patients critical information for the screening, diagnosis and treatment of multiple disease states.

In addition to offering this advanced HIV diagnostic tool, LabCorp introduced a new diagnostic algorithm that significantly improves the screening and diagnosis of HIV infection. The algorithm uses the 4^th generation test as a first step, with subsequent confirmation of the initial HIV-positive result with a highly sensitive and specific immunoassay that is FDA approved to differentiate between HIV-1 and HIV-2 infections. Inconsistent findings are further resolved by nucleic acid testing to identify potential early acute infection. The Clinical Laboratory Standards Institute (CLSI) and the New York State Department of Health have recommended the use of this enhanced algorithm for HIV screening and the Centers for Disease Control and Prevention (CDC) has recently issued two positive evaluations of the new HIV diagnostic testing algorithm on its online Morbidity and Mortality Weekly Report. The algorithm is configured to be cost-effective for patients and payers while providing high quality results.

"Fourth-generation HIV screening and associated supplemental testing is a valuable addition to the tools available to achieve early diagnosis of HIV," said Dr. Mark Brecher, LabCorp's Chief Medical Officer. "Detection of acute infections using the fourth-generation assay provides an improved opportunity for early intervention and the potential to affect transmission rates."