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Updated: Jul 5, 2026
05:46
Rapid Screening of HIV Reverse Transcriptase and Integrase Inhibitors
Published on: April 9, 2014
Changing patterns in HIV reverse transcriptase resistance mutations after availability of tenofovir
Carmen de Mendoza1, Inmaculada Jiménez-Nacher, Carolina Garrido
1Department of Infectious Diseases, Hospital Carlos III, Madrid, Spain. cmendoza@teleline.es
Summary
The incidence of the K65R mutation in human immunodeficiency virus (HIV) isolates decreased significantly, despite stable tenofovir use. This reduction was primarily linked to decreased coadministration of didanosine.
Area of Science:
- Virology
- Infectious Diseases
- Pharmacology
Background:
- The K65R mutation is a key mechanism of antiviral resistance in human immunodeficiency virus (HIV).
- Tenofovir is a cornerstone of modern antiretroviral therapy (ART).
- Understanding resistance patterns is crucial for optimizing HIV treatment strategies.
Purpose of the Study:
- To investigate trends in the K65R mutation incidence in HIV-1 infected patients.
- To determine the factors associated with observed changes in K65R mutation rates.
- To assess the impact of tenofovir and didanosine use on HIV resistance.
Main Methods:
- Retrospective analysis of 1177 HIV resistance genotypes from an HIV/AIDS clinic.
- Comparison of K65R mutation incidence between 2002-2004 and 2005-2006.
- Assessment of tenofovir and didanosine coadministration rates during the study periods.
Main Results:
- A significant decrease in K65R mutation incidence was observed, from 15.2% (2002-2004) to 2.7% (2005-2006) (P < .001).
- Tenofovir use remained elevated and stable throughout the study periods.
- A substantial reduction in didanosine coadministration (41.6% in 2004 to 0.8% in 2006; P < .001) correlated with the decrease in K65R mutations.
Conclusions:
- The decline in K65R mutation incidence is largely attributable to the reduced use of didanosine in combination ART regimens.
- This finding highlights the importance of drug-drug interactions and specific antiretroviral combinations in shaping HIV resistance profiles.
- Optimizing ART regimens by avoiding specific drug combinations, like tenofovir with didanosine, can mitigate the emergence of key resistance mutations.
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