Introduction: In addition, there is a strong negative association of K65R with the M184V, L74V and K70E mutations, conferring resistance to 3TC/FTC, ddI and TDF, respectively.
Introduction: There was a lower incidence of the K65R and L74V in ABC regimens containing AZT than in those without.
Discussion: The facilitated development of K65R, M184V and/or L74V as a minority species leads to early treatment failure with suboptimal treatment regimens, in particular d4T, ddI, NVP and triple-NRTI drug combinations.
Design and profiling of GS-9148, a novel nucleotide analog active against nucleoside-resistant variants of human immunodeficiency virus type 1, and its orally bioavailable phosphonoamidate prodrug, GS-9131.
PMID: 18056282
2008
Antimicrobial agents and chemotherapy
Abstract: Notably, antiviral resistance analysis indicated that neither the K65R, L74V, or M184V RT mutation nor their combinations had any effect on the antiretroviral activity of GS-9148.
Association of efavirenz hypersusceptibility with virologic response in ACTG 368, a randomized trial of abacavir (ABC) in combination with efavirenz (EFV) and indinavir (IDV) in HIV-infected subjects with prior nucleoside analog experience.
Abstract: In addition, L74V, when combined with K103N+L100I, may confer a selective advantage to the virus that is independent of its effects on nucleoside resistance.
Abstract: In some patients on the nucleoside-sparing arm, the nucleoside-resistance mutation L74V was selected for in combination with the uncommonly occurring EFV-resistance mutations K103N+L100I; L74V was not detected as a minority variant, using clonal sequence analysis, when the nucleoside-sparing regimen was initiated.
Targeting only reverse transcriptase with zidovudine/lamivudine/abacavir plus tenofovir in HIV-1-infected patients with multidrug-resistant virus: a multicentre pilot study.
Abstract: K65R was associated with reduced susceptibility to tenofovir, didanosine, abacavir and lamivudine; L74V/I was associated with reduced susceptibility to abacavir and didanosine.
Abstract: HIV-1 with K65R or L74V/I alone were fully susceptible to zidovudine and stavudine.
Abstract: TAMs were rarely observed in combination with K65R, but frequently associated with L74V/I.
Abstract: The addition of M184V to either K65R or L74V/I improved susceptibility to tenofovir, zidovudine and stavudine, but reduced susceptibility to abacavir, didanosine and lamivudine.
Abstract: The replication capacity for HIV-1 with
Prevalence, genotypic associations and phenotypic characterization of K65R, L74V and other HIV-1 RT resistance mutations in a commercial database.
Abstract: Only 1 of 49 genotyped specimens had mutations associated with drug resistance (L74V and Y181C) in the reverse transcriptase gene, indicating that the prevalence of transmitted HIVDR to all drugs and drug classes evaluated was <5%.
Impact of human immunodeficiency virus type 1 reverse transcriptase inhibitor drug resistance mutation interactions on phenotypic susceptibility.
PMID: 18844463
2008
AIDS research and human retroviruses
Abstract: In virus strains with the nonnucleoside reverse transcriptase inhibitor (NNRTI) mutations K101E and G190S, the L74V mutation increased replication capacity, consistent with published observations, but replication capacity was decreased in strains without NNRTI resistance mutations.
Abstract: The L74V mutation had similar but slightly different effects, contributing to decreased susceptibility to abacavir, lamivudine, and didanosine and increased susceptibility to zidovudine and tenofovir, but in contrast to M184V, L74V contributed to decreased susceptibility to stavudine.
Silent mutations are selected in HIV-1 reverse transcriptase and affect enzymatic efficiency.
Introduction: The K65R, K70E, L74V, Q151M and M184V mutations primarily increase the selectivity of RT for the incorporation of a natural dNTP substrate over a NRTI-triphosphate.