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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Amino Acid Substitution, Anti-HIV Agents, Drug Resistance, Viral, Genotype, Genotyping Techniques, HIV Integrase, HIV-1, Heterocyclic Compounds, 3-Ring, Humans, Mutation, Missense, Quinolones, Raltegravir Potassium, Selection, Genetic, Virus Cultivation.
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Is the dolutegravir R263K resistance mutation in HIV-1 integrase incompatible with the emergence of resistance against raltegravir? Context: Although the integrase inhibitor dolutegravir (DTG) has demonstrated greater resilience than other antiretroviral drugs at withstanding the emergence of HIV-1 resistance mutations, such substitutions can develop, albeit rarely, in treatment-experienced integrase inhibitor-naïve individuals. The most common substitution in integrase under those circumstances is R263K whereas another substitution that was selected against DTG in tissue culture was G118R. The objective of this study was to determine the effects of these DTG-specific resistance substitutions on the ability of HIV-1 to become resistant against either of two other integrase inhibitors, raltegravir (RAL) and elvitegravir (EVG). We performed tissue culture selection experiments using DTG-resistant viruses containing integrase substitutions at positions R263K, H51Y/R263K, E138K/R263K, G118R and H51Y/G118R in the presence of increasing concentrations of either RAL or EVG. Changes in integrase sequences were monitored by genotyping. The presence of the R263K substitution delayed the emergence of resistance against RAL whereas the simultaneous presence of either the H51Y or E138K secondary substitutions in combination with R263K somewhat mitigated this inhibitory effect. In contrast, resistance against EVG appeared earlier than in wild-type virus in viruses containing the R263K and E138K/R263K DTG-associated resistance substitutions.
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The DTG-resistant R263K substitution antagonized the development of HIV-1 resistance against RAL while partially facilitating the occurrence of resistance against EVG. Final Decision: yes