Evaluation of NucliSens EasyQ (TM) HIV-1 assay for quantification of HIV-1 subtypes prevalent in south-east Asia

Background: Monitoring anti-retroviral therapy requires that viral load assays for human immunodeficiency virus type I (HIV-1) be applicable to diverse HIV-1 subtypes. Objectives: To evaluate NucliSens EaSyQ (TM) HIV-1 assay for quantitation of common HIV-1 subtypes prevalent in South-east Asia. Study design: One hundred and nineteen plasma samples collected in Hong Kong and Cambodia were used to compare the performance of NucliSens EaSyQ (TM) HIV-1 and COBAS Amplicor (TM) HIV-1 Monitor version 1.5 assays. Viral RNA extracted from the NucliSens MiniMAG (TM) was also used for HIV-1 subtyping. Results: Performance of NucliSens EasyQ (TM) correlated well with COBAS Amplicor (TM) (r = 0.777, p < 0.001) and the small mean difference (0.0462 log(10) IU/mL) obtained in the Bland and Altman model indicated good agreement between two assays. The NucliSens EasyQ (TM) assay demonstrated a 95% sensitivity at 5001U/mL and 100% specificity. Reproducibility of this assay was within log(10) 2-4IU/mL and had a coefficient of variation between 2.3% and 10.4%. Among the 109 specimens included in the analysis, HIV-1 subtyping identified 64 CRF01_AE, 38 subtype B, 3 subtype C, 3 CRF07_BC and I subtype G viruses. Conclusions: Performance of NucliSens EasyQ (TM) was comparable to COBAS Amplicor (TM) for HIV-1 viral load monitoring. RNA extracts from NucliSens MiniMAG (TM) could be used for HIV-1 viral load monitoring, subtyping and drug resistance mutations detection. Our findings highlight the versatility of both NucliSens EaSyQ (TM) and COBAS Amplicor (TM) in monitoring prevalent subtypes and rare circulating recombinant forms (CRFs) in the South-east Asia region. (c) 2006 Elsevier B.V. All rights reserved.