The Viral Archive—A Second Source of Resistance Information
Differences can exist between the viral population circulating in the plasma and the proviral DNA archived in infected cells.
- Viral loads and standard resistance assays analyze viral RNA in plasma. However, in suppressed patients or patients with low-level viremia, there is an insufficient quantity of virus in the plasma to analyze.
- Monogram has developed technology to exploit the DNA left behind in cells during viral replication. GenoSure ArchiveSM and Trofile® DNA analyze this archived HIV-1 proviral DNA embedded in host cells.
- GenoSure Archive and Trofile DNA are performed by amplifying cell-associated HIV-1 DNA from infected cells in whole blood samples and then analyzing that DNA accordingly.
GenoSure Archive is the newest suppression management offering by Monogram Biosciences. GenoSure Archive is designed to provide HIV-1 antiretroviral (ARV) drug resistance data when standard resistance testing cannot be performed due to inadequate plasma viral load. The assay exploits peripheral blood mononuclear cells (PBMCs) in whole blood to interrogate the viral archive and uses next-generation sequencing (NGS) methods to provide a list of the archived mutations; then it assigns susceptibility calls of "sensitive," "resistant," or "resistance possible" based on those mutations. GenoSure Archive provides valuable information for nucleoside reverse transcriptase inhibitors (NRTIs), nonnucleoside reverse transcriptase inhibitors (NNRTIs), integrase inhibitors (INIs), and protease inhibitors (PIs) when regimen switches are being considered.
Download a sample report.
The Trofile DNA Co-Receptor Tropism Assay applies the proven performance of Trofile to cell-associated viral DNA. For patients with undetectable viral loads, Trofile DNA can be considered when a patient’s viral tropism is unknown and substitution with a CCR5 antagonist is desired. Unlike the standard Trofile assay, which uses viral RNA found in the plasma of patients with viral loads ≥ 1000 copies/mL, Trofile DNA uses viral DNA extracted from cells in a whole blood draw. Click here to view a sample report.