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Updated: Jun 26, 2026
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Quantitative Structure-Activity Relationship, Activity Prediction, and Molecular Dynamics of Non-nucleotide Reverse Transcriptase Inhibitors
Published on: May 9, 2025
Dynamics of NRTI resistance mutations during therapy interruption
Maria Trignetti1, Tobias Sing, Valentina Svicher
1Experimental Medicine Department, University of Rome Tor Vergata , 00133, Rome, Italy.
AIDS Research and Human Retroviruses
|February 3, 2009
Summary
Drug resistance mutations in nucleoside analogue reverse transcriptase inhibitors (NRTIs) are lost at varying rates during treatment interruption (TI). These mutations, like K65R and M184I/V, disappear rapidly and independently, impacting viral fitness.
Area of Science:
- Virology
- Pharmacology
- Epidemiology
Background:
- Limited data exists on the evolution of drug resistance mutations during treatment interruption (TI).
- Understanding mutation dynamics during TI is crucial for managing antiviral therapy and treatment strategies.
Purpose of the Study:
- To investigate the dynamics of nucleoside analogue reverse transcriptase inhibitor (NRTI) resistance mutations during TI.
- To determine the rates and patterns of NRTI resistance mutation loss during TI.
Main Methods:
- Survival analysis approach was used.
- Analysis included 132 patients with at least two consecutive genotypes, including one at regimen failure and one during TI.
- Rates of disappearance for individual NRTI resistance mutations were assessed.
Main Results:
- NRTI resistance mutations disappear at different rates during TI and are mostly lost independently.
- K65R and M184I/V mutations were rapidly lost in most patients, associated with wild-type virus reemergence.
- The loss of NRTI resistance mutations during TI is not an ordered process and occurs without significant interaction among mutations in most cases.
Conclusions:
- The loss of NRTI resistance mutations during TI is a complex, non-ordered process.
- Rapid disappearance of K65R and M184I/V suggests a negative impact on viral fitness.
- Findings provide insights into the evolutionary dynamics of drug resistance during TI.
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