Evaluation of the performance of a qPCR-based assay for HIV-1 viral load determination

by Bin Lin, Chao Han, Jin-Hai Li, Rui Wang

Objective

According to the YY/T 1182–2010 standard of the People’s Republic of China on nucleic acid amplification test reagents (kits) for medical industry, the accuracy, precision, linear range, and analytic sensitivity of HIV-1 standardized quality control products should be assessed. The Geneway HIV-1 Nucleic Acid Detection Kit from China has been successfully registered with the National Medical Products Administration. Here, we aimed to assess for the first time its detection performance.

Methods

The accuracy, precision, analytic sensitivity, and linearity of the Geneway HIV-1 nucleic acid quantification test kit were analyzed using a series of diluted standard control samples of HIV-1 negative plasma. Clinical plasma samples were collected from 163 HIV-infected patients and 38 HIV-negative patients. The detection performance of the Geneway assay was compared with that of the US FDA-approved COBAS AmpliPrep/COBAS® Taqman® HIV-1 test (Roche), version 2.0, for viral load (VL) monitoring.

Results

The absolute deviation of the assay between the logarithm of the measured concentration and the logarithm of the expected concentration did not exceed ±0.5 logarithmic units. All coefficients of variation (CV%) for the assays were within 5%, indicating good precision in the detection. The linearity of quantitation was excellent (r = 0.999). Overall agreement was observed in 198 of the 201 specimens (98.51%), with a kappa value of 0.953. Bland-Altman analysis revealed an average difference of 0.030 between the two assays, with 95.95% (142/148) of the differences falling within the 95% confidence limits of agreement (−0.50, 0.56). Linear regression results demonstrated a strong linear correlation between the two assays, with a high Pearson correlation coefficient (r = 0.980) and coefficient of determination (R² = 0.960, p < 0.001).

Conclusions

The Geneway HIV-1 VL assay demonstrated excellent accuracy, precision, analytic sensitivity, and linearity. Compared to the Roche assay, the Geneway assay showed good performance for HIV-1 VL detection, supporting its use in clinical practice.