Comparison of Roche Cobas AmpliPrep/Cobas TaqMan HIV-1 test version 2.0 (CAP/CTM v2.0) with other real-time PCR assays in HIV-1 monitoring and follow-up of low-level viral loads.

Viral load monitoring of HIV-1 has become standard of care in HIV-1 positive patients. In this study, we evaluated the performance characteristics of the Roche Cobas AmpliPrep/Cobas TaqMan HIV-1 test version 2.0 (CAP/CTM v2.0) in comparison with Roche Cobas AmpliPrep/Cobas TaqMan HIV-1 test version 1.0 (CAP/CTM v1.0) and Abbott RealTime HIV-1 assay (m2000), with special emphasis on the quantitation of clinically controversial low-level viral loads. The performance characteristics of CAP/CTM v2.0 were confirmed by the validation study. All three assays performed comparably, with Abbott m2000 showing slightly decreased sensitivity for detection of viral loads close to the lower limit of quantitation. Follow-up of patients with low-level viral loads revealed that some of those represent single viral blips; however, a significant portion of these patients have intermittent or persistent low-positive viremia. We conclude that CAP/CTM v2.0 is an accurate and reliable assay for HIV-1 viral load monitoring.