Agents Used in Antiretroviral Therapy

  • Authors: Philip Grant, MD (More Info)
  • Editors in Chief: Daniel R. Kuritzkes, MD; Joseph J. Eron, Jr., MD
  • Last Reviewed: 7/19/21 (What's New)



  • 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)
    • Attachment
    • 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
    Uncoating and Reverse Transcription