Virological suppression reduces clinical progression in patients with multiclass-resistant HIV type 1.

The virological and immunological outcomes in patients carrying multiclass-resistant HIV-1, their predictors, and their impact on disease progression were investigated. Antiretroviral-experienced patients carrying at least one primary resistance mutation (IAS-USA 2006) to two to three classes of antiretroviral drugs were analyzed for achieving an HIV-1 RNA <50 copies/ml, a CD4 count increase of >200 cells/microl from baseline, and progression to an AIDS-defining event or death. Survival analysis was performed using the Kaplan-Meier estimates and predictors of different outcomes were analyzed using Cox's regression models. A total of 236 patients were identified. Of these 73% reached HIV-1 RNA <50 copies/ml. Higher genotypic sensitivity score of the salvage regimen, lower viral load, and more recent calendar year at genotyping were independently associated with virological response. Immunological response (58%) was predicted by a more recent calendar year, the achievement of an undetectable viral load, and higher CD4 counts at genotyping. Thirty-three patients showed clinical progression: achieving HIV-1 RNA <50 copies/ml predicted AIDS-free survival, independently from other significant cofactors. In individuals with multiclass-resistant HIV-1, virological suppression and immunological recovery are becoming more easily accessible with more recent therapies. The achievement of virological suppression is a strong predictor of reduced clinical progression.