title: Combination of V106I and V179D polymorphic mutations in human immunodeficiency virus type 1 reverse transcriptase confers resistance to efavirenz and nevirapine but not etravirine.
abstract: Etravirine (ETV) is a second-generation nonnucleoside reverse transcriptase (RT) inhibitor (NNRTI) introduced recently for salvage antiretroviral treatment after the emergence of NNRTI-resistant human immunodeficiency virus type 1 (HIV-1). Following its introduction, two naturally occurring mutations in HIV-1 RT, V106I and V179D, were listed as ETV resistance-associated mutations. However, the effect of these mutations on the development of NNRTI resistance has not been analyzed yet. To select highly NNRTI-resistant HIV-1 in vitro, monoclonal HIV-1 strains harboring V106I and V179D (HIV-1(V106I) and HIV-1(V179D)) were propagated in the presence of increasing concentrations of efavirenz (EFV). Interestingly, V179D emerged in one of three selection experiments from HIV-1(V106I) and V106I emerged in two of three experiments from HIV-1(V179D). Analysis of recombinant HIV-1 clones showed that the combination of V106I and V179D conferred significant resistance to EFV and nevirapine (NVP) but not to ETV. Structural analysis indicated that ETV can overcome the repulsive interactions caused by the combination of V106I and V179D through fine-tuning of its binding module to RT facilitated by its plastic structure, whereas EFV and NVP cannot because of their rigid structures. Analysis of clinical isolates showed comparable drug susceptibilities, and the same combination of mutations was found in some database patients who experienced virologic NNRTI-based treatment failure. The combination of V106I and V179D is a newly identified NNRTI resistance pattern of mutations. The combination of polymorphic and minor resistance-associated mutations should be interpreted carefully.
authors.affiliation: AIDS Clinical Center, International Medical Center of Japan, 1-21-1 Toyama, Shinjuku-ku, Tokyo 162-8655, Japan. higatana@imcj.acc.go.jp
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Gatanaga
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Ode
authors.forename: Atsuko
authors.initials: A
authors.lastname: Hachiya
authors.forename: Tsunefusa
authors.initials: T
authors.lastname: Hayashida
authors.forename: Hironori
authors.initials: H
authors.lastname: Sato
authors.forename: Shinichi
authors.initials: S
authors.lastname: Oka
mesh_terms: D000480:Alkynes; D019943:Amino Acid Substitution; D019380:Anti-HIV Agents / Q000737:chemistry / Q000494:pharmacology*; D048588:Benzoxazines / Q000737:chemistry / Q000494:pharmacology*; D003521:Cyclopropanes; D024882:Drug Resistance, Viral / Q000235:genetics; D005814:Genes, Viral; D015658:HIV Infections / Q000188:drug therapy / Q000821:virology; D054303:HIV Reverse Transcriptase / Q000737:chemistry / Q000235:genetics*; D015497:HIV-1 / Q000187:drug effects* / Q000235:genetics* / Q000302:isolation & purification / Q000502:physiology; D006801:Humans; D066298:In Vitro Techniques; D008958:Models, Molecular; D020125:Mutation, Missense; D019829:Nevirapine / Q000737:chemistry / Q000494:pharmacology*; D009570:Nitriles; D011724:Pyridazines / Q000737:chemistry / Q000494:pharmacology; D011743:Pyrimidines; D011995:Recombination, Genetic; D014779:Virus Replication / Q000187:drug effects / Q000235:genetics
chemical_list: D000480:Alkynes; D019380:Anti-HIV Agents; D048588:Benzoxazines; D003521:Cyclopropanes; D009570:Nitriles; D011724:Pyridazines; D011743:Pyrimidines; C451734:etravirine; D019829:Nevirapine; C514824:reverse transcriptase, Human immunodeficiency virus 1; D054303:HIV Reverse Transcriptase; C098320:efavirenz