Potent combination antiretroviral therapy has changed the prognosis for patients with HIV infection
This module describes the HIV life cycle, currently available antiretroviral agents, and agents in phase III clinical trials
Some agents are available separately (Table 1) or as part of coformulations (Table 2)
HIV Viral Life Cycle
There are 6 available classes of antiretroviral therapy targeting several steps of HIV lifecycle (Figure 1)
Coreceptor binding
Fusion
Reverse transcription
Integration
Assembly
Attachment; Coreceptor Binding; Fusion
Attachment of HIV surface envelope protein gp120 to CD4 receptor is the first step in viral infection of the cell
Conformational change in gp120 enables binding to 1 of 2 beta-chemokine coreceptors, CCR5 or CXCR4
When HIV is bound to both CD4 and chemokine receptor, an additional conformational change allows viral envelope and host cell membrane to come into contact
Fusion peptide gp41 penetrates cell membrane, triggering repeat sequences in gp41 (referred to as heptad repeat 1 and 2) to interact leading to fusion of viral and cell membranes
