Monitoring the efficacy of antiretroviral therapy by a simple reverse transcriptase assay in HIV-infected adults in rural Vietnam

Aim: To determine the feasibility of viral load (VL) monitoring using ExaVir (TM) Load in a cohort of 605 HIV treatment-naive adult patients initiating antiretroviral therapy in rural Vietnam. Materials & methods: VL monitoring every 6 months, survival and intention-to-treat analysis were used. Roche Cobas TaqMan (R) VL was compared with ExaVir Load using Spearman's rank correlation coefficient and Bland-Altman analysis. Results: After 20.7 months mean follow-up time, 78% remained on treatment. Virologic suppression rate (VL <200 copies/ml) after 24 months was 64% in the whole cohort and 94% among patients assessed with VL. The cumulative virologic failure rate (VL >1000 copies/ml) was 6.8%. Baseline VL >= 100,000 copies/ml was predictive for virologic failure (adjusted hazard ratio: 2.26 (1.16-4.39); p = 0.016). ExaVir Load and the Roche Cobas TaqMan showed a strong correlation (r(2) = 0.97; p < 0.001), high agreement (difference in log = 0.34; 95% CI: -0.35-1.03), high sensitivity (98%) and high specificity (100%). Conclusion: Using ExaVir Load to monitor efficacy of antiretroviral therapy programs in resource-limited settings is feasible.