Prevalence of major protease inhibitors (PIs) mutations for darunavir and tipranavir resistancein samples of experienced HIV patients from Buenos Aires

M.INÉS FIGUEROA; OMAR SUED; NATALIA LAUFER; FRANCO MORETTI; SANDRA PAMPURO; RICARDO TEJEIRO; MANUEL GOMEZ CARRILLO; HORACIO SALOMÓN; PEDRO CAHN

MEXICO DF. MEXICO

Conferencia; AIDS 2008. XVII INTERNATIONAL AIDS CONFERENCE; 2008

INTERNATIONAL AIDS SOCIETY

Background: Increasing use of PIs results in the emergence of resistance. New PIs have higher genetic barrier but their response could be diminished with the number of previous resistance mutations. Objectives: To describe the prevalence of mutations associated with resistance to new PIs in a single resistance database in Buenos Aires. Methods: We used data sequences from 2,959 samples of HIV experienced patients collected at the Argentinean National Reference Center for AIDS (2001-2007). Virco®Type was used for genotyping. These data were analyzed to describe major mutations to darunavir and tipranavir (according IAS 2007): 50V, 54M/L, 76V and 84V for darunavir; and 33F, 82L/T and 84V for tipranavir. darunavir and 430 (14.5%;95%CI 13.2-15.8) for tipranavir. Frequencies recorded: 50V: 1.3%; 54M/L: 3.2%; 76V: 2.6%; 84V: 6.9%; 33F: 7.7%; 82L/T: 2.1%. No sample presented the four DRV major mutations simultaneously, only one presented the three major TPV mutations. Prevalence of some mutations changed over time: 54M/L was 0.43% in 2001 and >2.75% in the following years; 76V was absent until 2004, and >2.9% thereafter; 33F increased from 3% in 2001 to 10% in 2007. Other mutations did not show significant changes over the period. Objectives: To describe the prevalence of mutations associated with resistance to new PIs in a single resistance database in Buenos Aires. Methods: We used data sequences from 2,959 samples of HIV experienced patients collected at the Argentinean National Reference Center for AIDS (2001-2007). Virco®Type was used for genotyping. These data were analyzed to describe major mutations to darunavir and tipranavir (according IAS 2007): 50V, 54M/L, 76V and 84V for darunavir; and 33F, 82L/T and 84V for tipranavir. darunavir and 430 (14.5%;95%CI 13.2-15.8) for tipranavir. Frequencies recorded: 50V: 1.3%; 54M/L: 3.2%; 76V: 2.6%; 84V: 6.9%; 33F: 7.7%; 82L/T: 2.1%. No sample presented the four DRV major mutations simultaneously, only one presented the three major TPV mutations. Prevalence of some mutations changed over time: 54M/L was 0.43% in 2001 and >2.75% in the following years; 76V was absent until 2004, and >2.9% thereafter; 33F increased from 3% in 2001 to 10% in 2007. Other mutations did not show significant changes over the period.Methods: We used data sequences from 2,959 samples of HIV experienced patients collected at the Argentinean National Reference Center for AIDS (2001-2007). Virco®Type was used for genotyping. These data were analyzed to describe major mutations to darunavir and tipranavir (according IAS 2007): 50V, 54M/L, 76V and 84V for darunavir; and 33F, 82L/T and 84V for tipranavir. darunavir and 430 (14.5%;95%CI 13.2-15.8) for tipranavir. Frequencies recorded: 50V: 1.3%; 54M/L: 3.2%; 76V: 2.6%; 84V: 6.9%; 33F: 7.7%; 82L/T: 2.1%. No sample presented the four DRV major mutations simultaneously, only one presented the three major TPV mutations. Prevalence of some mutations changed over time: 54M/L was 0.43% in 2001 and >2.75% in the following years; 76V was absent until 2004, and >2.9% thereafter; 33F increased from 3% in 2001 to 10% in 2007. Other mutations did not show significant changes over the period. Conclusions: Major mutations for new PIs are present in more than 10% of our experienced patients. Frequency of some mutations (55M/L; 76V for darunavir and 33F for tipranavir) increased while 50V, 84V and 82 L/T remained stables. These changes might be linked to cross resistance with other PIs, as darunavir and tipranavir were introduced in our country in 2006 and 2007 respectively. The correlation of these major mutations, minor mutations and clinical implications warrants further research.