Performance Characteristics of the QUANTIPLEX HIV-1 RNA 3.0 Assay for Detection and Quantitation of Human Immunodeficiency virus Type 1 RNA in Plasma [Erice A, et al. JCM 2000; 38: 2837]: This is a six-laboratory study that compared the AMPLICOR HIV-1 Monitor Ultrasensitive PCR assay (Roche) and the QUANTIPLEX HIV-1bDNA RNA version 3.0 assay (Bayer, formerly Chiron) using specimens that had been spiked and clinical samples. Over 1,300 assays were performed. The limit of detection for the bDNA assay was 100 copies/mL and for RT-PCR was 50 copies/mL. The frequency of false-positive tests (tests indicating over 50 copies/mL in HIV-negative specimens) was 6.2 % with the bDNA 3.0 assay. There was a linear range for the bDNA assay from 100 to 500,000 copies/mL, and this represents a 10-fold increase compared to the linear range of the RT-PCR assay (50 - 75,000 copies/mL). Variations in the assay were smaller for the bDNA assay. Comparison of the two assays showed that the values obtained by the RT-PCR assay averaged 2-fold higher than the bDNA 3.0 assay on the same sample. The authors concluded that the QUANTIPLEX HIV-1 RNA 3.0 assay shows excellent results with good reproducibility, a broad linear range from 100 to 500,000 copies/mL, and good sensitivity.
Comment: This is an important study to document the value of the QUANTIPLEX HIV-1 RNA 3.0 assay, which has the potential advantage over the RT-PCR of a broad range that is 100 - 500,000 copies/mL compared to 50 - 75,000 copies/mL. The threshold for detection was somewhat higher at 100 copies/mL compared to 50 copies/mL for the RT-PCR test, but as the authors point out, it is not clear that this is a difference that is clinically relevant. Overall, the performance of the 3.0 assay version seemed excellent. posted 8/29/2000