Sustained CD4+ T cell response after virologic failure of protease inhibitor-based regimens in patients with human immunodeficiency virus infection

The relationship between plasma human immunode®ciency virus (HIV) RNA levels and peripheral CD4+ T cell counts was examined in 380 HIV-infected adults receiving long-term protease inhibitor therapy. Patients experiencing virologic failure (persistent HIV RNA 1500 copies RNA/mL) generally had CD4+ T cell counts that remained greater than pretherapy baseline levels, at least through 96 weeks of follow-up. The CD4+ T cell response was directly and independently related to degree of viral suppression below the pretreatment baseline. For any given HIV RNA level measured 12 weeks after virologic failure, subsequent CD4+ T cell decline was slower in patients receiving a protease inhibitor±based regimen than in a historical control group of untreated patients. These observations suggest that transient or partial de-clines in plasma HIV RNA levels can have sustained effects on CD4+ T cell levels. The goal of antiretroviral therapy for human immunode®-ciency virus (HIV) infection is to lengthen and improve the quality of the patient's life. According to current clinical guide-lines, the optimal way to achieve this goal is by use of com-bination therapy to reduce HIV RNA levels below the level o