Emergence of HIV-1 drug resistance in previously untreated patients initiating combination antiretroviral treatment: a comparison of different regimen types

Publication

Emergence of HIV-1 drug resistance in previously untreated patients initiating combination antiretroviral treatment: a comparison of different regimen types

Journal Paper/Review - Sep 10, 2007

von Wyl Viktor, Günthard Huldrych F, Ledergerber Bruno, Perrin Luc, Rickenbach Martin, Bernasconi Enos, Vernazza Pietro, Hirschel Bernard, Telenti Amalio, Furrer Hansjakob, Battegay Manuel, Klimkait Thomas, Bürgisser Philippe, Böni Jürg, Yerly Sabine, for the Swiss HIV Cohort Study

Citation

von Wyl V, Günthard H, Ledergerber B, Perrin L, Rickenbach M, Bernasconi E, Vernazza P, Hirschel B, Telenti A, Furrer H, Battegay M, Klimkait T, Bürgisser P, Böni J, Yerly S, for the Swiss HIV Cohort Study. Emergence of HIV-1 drug resistance in previously untreated patients initiating combination antiretroviral treatment: a comparison of different regimen types. Archives of internal medicine 2007; 167:1782-90.

Type

Journal Paper/Review (English)

Journal

Archives of internal medicine 2007; 167

Publication Date

Sep 10, 2007

Issn Print

0003-9926

Pages

1782-90

Brief description/objective

BACKGROUND: Standard first-line combination antiretroviral treatment (cART) against human immunodeficiency virus 1 (HIV-1) contains either a nonnucleoside reverse transcriptase inhibitor (NNRTI) or a ritonavir-boosted protease inhibitor (PI/r). Differences between these regimen types in the extent of the emergence of drug resistance on virological failure and the implications for further treatment options have rarely been assessed. METHODS: We investigated virological outcomes in patients from the Swiss HIV Cohort Study initiating cART between January 1, 1999, and December 31, 2005, with an unboosted PI, a PI/r, or an NNRTI and compared genotypic drug resistance patterns among these groups at treatment failure. RESULTS: A total of 489 patients started cART with a PI, 518 with a PI/r, and 805 with an NNRTI. A total of 177 virological failures were observed (108 [22%] PI failures, 24 [5%] PI/r failures, and 45 [6%] NNRTI failures). The failure rate was highest in the PI group (10.3 per 100 person-years; 95% confidence interval [CI], 8.5-12.4). No difference was seen between patients taking a PI/r (2.7; 95% CI, 1.8-4.0) and those taking an NNRTI (2.4; 95% CI, 1.8-3.3). Genotypic test results were available for 142 (80%) of the patients with a virological treatment failure. Resistance mutations were found in 84% (95% CI, 75%-92%) of patients taking a PI, 30% (95% CI, 12%-54%) of patients taking a PI/r, and 66% (95% CI, 49%-80%) of patients taking an NNRTI (P < .001). Multidrug resistance occurred almost exclusively as resistance against lamivudine-emtricitabine and the group-specific third drug and was observed in 17% (95% CI, 9%-26%) of patients taking a PI, 10% (95% CI, 0.1%-32%) of patients taking a PI/r, and 50% (95% CI, 33%-67%) of patients taking an NNRTI (P < .001). CONCLUSIONS: Regimens that contained a PI/r or an NNRTI exhibited similar potency as first-line regimens. However, the use of a PI/r led to less resistance in case of virological failure, preserving more drug options for the future.