[show abstract][hide abstract] ABSTRACT: Commercial HIV-1 genotypic resistance assays are very expensive, particularly for use in resource-constrained settings like India. Hence a cost effective in-house assay for drug resistance was validated against the standard ViroSeq HIV-1 Genotyping System 2.0 (Celera Diagnostics, CA, USA). A total of 50 samples were used for this evaluation (21 proficiency panels and 29 clinical isolates). Known resistance positions within HIV-1 protease (PR) region (1-99 codons) and HIV-1 reverse-transcriptase (RT) region (1-240 codons) were included. The results were analysed for each codon as follows: (i) concordant; (ii) partially concordant; (iii) indeterminate and (iv) discordant. A total of 2750 codons (55 codons per patient samplex50 samples) associated with drug resistance (1050 PR and 1700 RT) were analysed. For PR, 99% of the codon results were concordant and 1% were partially concordant. For RT, 99% of the codon results were concordant, 0.9% were partially concordant and 0.1% were discordant. No indeterminate results were observed and the results were reproducible. Overall, the in-house assay provided comparable results to those of US FDA approved ViroSeq, which costs about a half of the commercial assay ($ 100 vs. $ 230), making it suitable for resource-limited settings.
Journal of virological methods 09/2009; 159(2):211-6. · 2.13 Impact Factor
[show abstract][hide abstract] ABSTRACT: Continuation of failed highly active antiretroviral therapy regimens can lead to the accumulation of mutations that may limit options for second-line treatment. We studied the pattern of drug resistance mutations among 138 Indian patients who experienced failure of nonnucleotide reverse-transcriptase-containing first-line highly active antiretroviral therapy. This study demonstrates a high frequency of drug resistance mutations in human immunodeficiency virus-infected Indians who experience immunologic treatment failure and suggests the need for viral load monitoring.