HIV-1 genotypic drug resistance interpretation rules - 2009 Spanish guidelines

AIDS Rev. Jan-Mar 2009;11(1):39-51.


Interpreting the results of drug resistance tests for HIV-1 is one of the most difficult tasks for both clinicians and virologists. There are many amino acid changes in viral proteins influencing the susceptibility to specific drugs, causing loss of activity or conversely hypersusceptibility. Moreover, the results of interactions derived from complex mutational patterns are difficult to predict. Different interpretation algorithms have been developed to facilitate the translation of information obtained in the genotypes to clinicians. Controversy exists, however, regarding the impact of genotypic changes over the activity of many antiretroviral drugs. Based on virologic outcomes, scientific literature, and expert opinion, the Drug Resistance Platform of the Spanish AIDS Research Network (RIS, Red de Investigación en SIDA) has developed over the last years its own interpretation system. Herein, we present the 2009 guidelines, in which special efforts have been made to standardize the criteria for interpreting resistance mutations for compounds within the same drug family and to facilitate the clinical interpretation of HIV-1 resistance genotypes.

Publication types

  • Practice Guideline
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Algorithms
  • Amino Acid Sequence
  • CCR5 Receptor Antagonists
  • Drug Resistance, Viral / genetics*
  • Genotype
  • HIV Fusion Inhibitors / pharmacology
  • HIV Infections / drug therapy*
  • HIV Infections / genetics
  • HIV Infections / virology*
  • HIV-1 / genetics*
  • Humans
  • Integrase Inhibitors / pharmacology
  • Molecular Sequence Data
  • Mutation / drug effects
  • Protease Inhibitors / pharmacology
  • Reverse Transcriptase Inhibitors / pharmacology
  • Spain


  • CCR5 Receptor Antagonists
  • HIV Fusion Inhibitors
  • Integrase Inhibitors
  • Protease Inhibitors
  • Reverse Transcriptase Inhibitors