Montaner JS, Burnside A, Jayaweera D, Barylski C, de Caprariis PJ; International Conference on AIDS.

Int Conf AIDS. 2002 Jul 7-12; 14: abstract no. B10424.

St. Paul's Hospital, University of British Columbia, Vancouver, B.C., Canada

OBJECTIVE: A prospective, open-label study of 154 antiretroviral naive HIV patients randomized to saquinavir/ritonavir (SQV/r; 1600mg/100mg) once daily or efavirenz (EFV; 600mg) once daily, each in combination with 2 nucleoside analogs. An objective of this study is to evaluate the virologic resistance patterns associated with once daily SQV/r versus EFV. METHODS: HIV RNA response through week 24 was reviewed in both the SQV/r group and the EFV group. Genotyping and virtual phenotyping (VP) was performed on all patients at baseline and those with HIV RNA levels >1000 copies/mL at weeks 12-24. RESULTS: Virologic samples from 10 patients in the SQV/r arm and 5 patients in the EFV arm were tested. SQV/r baseline samples did not exhibit any VP resistance to the NRTIs, NNRTIs, or PIs . Post baseline SQV/r results include: Five patients did not develop genotypic mutations or VP resistance patterns. Three patients developed VP resistance (>10 fold) to lamivudine by week 16. One patient developed resistance (>10 fold) to nevirapine, delavirdine, and efavirenz at week 12. Intermediate VP resistance (4-10 fold) was identified to nelfinavir in 1 patient at week 12 (mutations at 77I and 88D). EFV results include: One patient showed VP resistance to efavirenz (>10 fold ) at baseline and subsequently developed resistance to lamivudine at week 16. Four of 5 patients developed efavirenz resistance post baseline; of these patients, 1 also had resistance to lamivudine at baseline. All 5 patients in the EFV arm exhibited VP resistance (>10 fold) to efavirenz. CONCLUSION: HIV RNA levels >1000 copies/mL at weeks 12-24 were associated with varying resistance profiles in patients receiving once daily SQV/r or EFV. While all EFV treated patients typically showed NNRTI resistance, SQV/r patients did not demonstrate any significant level of resistance to PIs.

Publication Types:

• Meeting Abstracts

Keywords:

• AIDS Vaccines
• Acquired Immunodeficiency Syndrome
• Genotype
• HIV Infections
• HIV Seropositivity
• Humans
• Lamivudine
• Nevirapine
• Oxazines
• Phenotype
• Prospective Studies
• Ritonavir
• Saquinavir
• efavirenz
• genetics

Other ID:

• GWAIDS0020812

UI: 102259890

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