Analysis of HIV-1 mutation patterns in patients failing antiretroviral therapy

The emergence of mutations encoding drug resistance is supposed to be a sig nificant limitation to the clinical efficacy of inhibitor compounds directe d against specific HIV-1 enzymatic targets. We have used a commercial test (Visible Genetics inc., Paris, France) to study the prevalence of mutations occurred in HIV-1 protease and reverse transcriptase (RT) genes in 93 HIV- 1. infected patients treated with at least one regimen containing a proteas e inhibitor (PI) and failing to the current therapeutic regimen. Protease m utations conferring resistance to at least one PI were detected in 46/93 (4 9.4%) of strains, 25 (26.8%) of which showed resistance to all Pls. Reverse transcriptase mutations conferring resistance to at least one RT inhibitor were detected in 57/93 (61.2%) of strains, 18 (19.3%) of which showed resi stance to all RT inhibitors. The most frequent RT mutations were T215Y/F, M 41L, and M184V (41.9, 40.8, and 40.8%, respectively), while L63P, L10R/V, a nd A71V/ T (58, 41.9, and 34.4%, respectively) were the most represented pr otease substitutions. We have found no mutations encoding for multiple dide oxynucleoside resistance (Q151M or T69SS). Twelve of our patients (12.9%) h ad no mutation encoding drug resistance and were completely sensitive to al l RT and protease inhibitors. Therefore, not ail virological failures are c aused by HIV-I genomic resistance. J. Clin. Lab. Anal. 15:43-46, 2001. (C) 2001 Wiley-Liss, Inc.