RT mutations patterns associated with cross resistance to NRTI or NNRTI in samples of experienced HIV patients from Buenos Aires

MARÍA I. FIGUEROA; OMAR SUED; NATALIA LAUFER; FRANCO MORETTI; SANDRA PAMPURO; MANUEL GOMEZ CARRILLO; HORACIO SALOMÓN; PEDRO CAHN

México DF, México

Conferencia; AIDS 2008 - XVII International AIDS Conference; 2008

International AIDS Society

Background: Resistance mutations increase with ARV use. Surveillance studies are needed to evaluate potential usefulness of new drugs in experienced patients.Resistance mutations increase with ARV use. Surveillance studies are needed to evaluate potential usefulness of new drugs in experienced patients. Objective: To describe the prevalence of RT mutations associated with cross resistance to NRTI or NNRTI ARVs in one Resistance  Database in Buenos Aires.To describe the prevalence of RT mutations associated with cross resistance to NRTI or NNRTI ARVs in one Resistance  Database in Buenos Aires. Methods: We used data sequences from 2959 samples of HIV experienced patients collected at the Argentinean National Reference Center for AIDS (2001-2007). Virco®Type was used for genotyping. We analyzed RT mutations patterns associated with cross-resistance to NRTI/NNRTI. MultiNRTI resistance mutations were defined as any of 65R, 69ins, 151M or simultaneous presence of 6 TAMs (41L, 67N, 70R, 210W, 215Y/F, 219Q/E)(IAS 2007). MultiNNRTI resistance was considered when 103N was present.We used data sequences from 2959 samples of HIV experienced patients collected at the Argentinean National Reference Center for AIDS (2001-2007). Virco®Type was used for genotyping. We analyzed RT mutations patterns associated with cross-resistance to NRTI/NNRTI. MultiNRTI resistance mutations were defined as any of 65R, 69ins, 151M or simultaneous presence of 6 TAMs (41L, 67N, 70R, 210W, 215Y/F, 219Q/E)(IAS 2007). MultiNNRTI resistance was considered when 103N was present. Results: 238 samples (8%;95%CI:7-9.1) were resistant to NRTI. Mutations 65R, T69ins, Q151M and 6TAMs were present in 2.5%, 1.32%, 3.3% and 1.4%., respectively. Significant changes were seen for 65R and 151M, with an increase during 2003-2004 and a tendency to diminish thereafter. For NNRTI 572 (33.2%; 95%CI 31.5-34.9) of the patients presented the mutation 103N, without significant changes over the period.238 samples (8%;95%CI:7-9.1) were resistant to NRTI. Mutations 65R, T69ins, Q151M and 6TAMs were present in 2.5%, 1.32%, 3.3% and 1.4%., respectively. Significant changes were seen for 65R and 151M, with an increase during 2003-2004 and a tendency to diminish thereafter. For NNRTI 572 (33.2%; 95%CI 31.5-34.9) of the patients presented the mutation 103N, without significant changes over the period. Conclusions: MultiNRTI resistance is prevalent in our database. An 8% of our experienced patients have no NRTI options and one third are resistant to first-generation NNRTIs. Introduction of tenofovir (in 2003) could have prompted the emergency of 65R mutation. Partially supported by the Fogarty International Center/NIH AITRP Grant # 5D43 TW0010137.MultiNRTI resistance is prevalent in our database. An 8% of our experienced patients have no NRTI options and one third are resistant to first-generation NNRTIs. Introduction of tenofovir (in 2003) could have prompted the emergency of 65R mutation. Partially supported by the Fogarty International Center/NIH AITRP Grant # 5D43 TW0010137.