Performance of the TRUGENE HIV-1 genotyping assay in global clinical trials.
Int Conf AIDS 2002 Jul 7-12; 14:(abstract no. B10181)
Tau KR, Romack JC, Crose GA, Gilonske KD, Kapke GF Covance CLS, Indianapolis, United States
With increasing emerging resistance to antiretroviral therapies, HIV-1 genotyping is a powerful new technology for use in drug development and clinical trials. The performance of the TRUGENE HIV-1 genotyping assay in a central laboratory was determined. The bi-directional sequence of the protease and reverse transcriptase gene (to codon > 244) was generated using the TRUGENE HIV-1 genotyping kit. The accuracy of the assay was examined by split sample testing with an outside laboratory. Agreement between the sites was 100% for known drug mutations and 96.4% for polymorphisms. The inter-assay and intra-assay precision was 100%. The sensitivity of the assay using the standard specimen preparation was 1000 copies/mL and was 100 copies/mL when a concentration step was added. However, when the assay was used in large trials, samples with less than 1000 copies/mL did not generate sequence 100% of the time, even with the concentration step. A percentage of the samples did not generate a genotype, even with viral loads greater than 1000 copies/mL. In global trials approximately 6.2% of the samples tested did not generate a genotype. The highest percentage was observed in samples collected from Australia, with the lowest percentage observed in samples from North American sites. The basis for this phenomenon is still unclear, but potentially could be related to the higher proportion of non-B subtypes in different geographic areas. This trend is under further investigation. The GeneLibrarian software has been updated on a regular schedule to include newly recognized resistance mutations. The continual evolution of the software and the performance of the assay make it a viable technology for use in clinical trials.
Keywords: AEGIS, HIV-1, HIV-1 Reverse Transcriptase, Genotype, Clinical Trials, RNA-Directed DNA Polymerase, Mutation, Australia, genetics
