Entry inhibition of HIV-1 subtype C isolates

  • Lynn Morris
  • Mia Coetzer
  • Elin S. Gray
  • Tonie Cilliers
  • Kabamba B. Alexandre
  • Penny L. Moore
  • James M. Binley
Part of the Milestones in Drug Therapy book series (MDT)


The HIV shows an extraordinary degree of genetic diversity that in rare cases impacts on the efficacy of currently available anti-retroviral therapies [1]. There is less information on how genetic variability might affect the efficacy of a newer class of anti-retrovirals, the entry or fusion inhibitors. This group comprises a diverse collection of compounds that target both viral and host cell components blocking virus attachment and/or fusion and preventing infection and viral integration. Available data suggests that almost all genetic subtypes of HIV-1 engage the CD4 and coreceptor molecules. Thus entry inhibitors that target cellular proteins are likely to be equally efficacious across genetic subtypes. However, the efficacy of those that target the viral envelope glycoprotein is likely to be more impacted, given that as the envelope gene is the most variable of all HIV genes, showing up to 30% difference within HIV-1 and up to 55% between HIV-1 and HIV-2 ( Most entry inhibitors have been designed and tested based on HIV-1 subtype B viruses, and would therefore be expected to be most effective against viruses of this genetic subtype. There are few studies that have specifically explored the phenotypic sensitivity of different HIV subtypes to entry inhibitors. Since HIV-1 subtype C is now the most prevalent subtype globally, causing explosive epidemics in southern Africa, Ethiopia, India and China, we focus our review primarily on viruses of this subtype.


Entry Inhibitor Coreceptor Usage CCR5 Inhibitor Human Immunodeficiency Virus Entry Human Immunodeficiency Virus Subtype 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Birkhäuser Verlag/Switzerland 2007

Authors and Affiliations

  • Lynn Morris
    • 1
  • Mia Coetzer
    • 1
  • Elin S. Gray
    • 1
  • Tonie Cilliers
    • 1
  • Kabamba B. Alexandre
    • 1
  • Penny L. Moore
    • 1
  • James M. Binley
    • 2
  1. 1.AIDS Virus Research UnitNational Institute for Communicable DiseasesJohannesburgSouth Africa
  2. 2.Torrey Pines Institute for Molecular StudiesSan DiegoUSA

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