Characterization of novel non-nucleoside reverse transcriptase (RT) inhibitor resistance mutations at residues 132 and 135 in the 51 kDa subunit of HIV-1 RT

Several rare and novel NNRTI [non-nucleoside reverse transcriptase (RT) inhibitor] resistance mutations were recently detected at codons 132 and 135 in RTs from clinical isolates using the yeast-based chimaeric TyHRT (Ty1/HIV-1 RT) phenotypic assay. Ile132 and Ile135 form part of the β7–β8 loop of HIV-1 RT (residues 132–140). To elucidate the contribution of these residues in RT structure–function and drug resistance, we constructed twelve recombinant enzymes harbouring mutations at codons 132 and 135–140. Several of the mutant enzymes exhibited reduced DNA polymerase activities. Using the yeast two-hybrid assay for HIV-1 RT dimerization we show that in some instances this decrease in enzyme activity could be attributed to the mutations, in the context of the 51 kDa subunit of HIV-1 RT, disrupting the subunit–subunit interactions of the enzyme. Drug resistance analyses using purified RT, the TyHRT assay and antiviral assays demonstrated that the I132M mutation conferred high-level resistance (>10-fold) to nevirapine and delavirdine and low-level resistance (∼2–3-fold) to efavirenz. The I135A and I135M mutations also conferred low level NNRTI resistance (∼2-fold). Subunit selective mutagenesis studies again demonstrated that resistance was conferred via the p51 subunit of HIV-1 RT. Taken together, our results highlight a specific role of residues 132 and 135 in NNRTI resistance and a general role for residues in the β7–β8 loop in the stability of HIV-1 RT.

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Characteristics of drug resistance in HIV-1 CRF55_01B from ART-experienced patients in Guangdong, China

Journal of Antimicrobial Chemotherapy ◽

10.1093/jac/dkaa116 ◽

2020 ◽

Vol 75 (7) ◽

pp. 1925-1931 ◽

Cited By ~ 1

Author(s):

Yun Lan ◽

Ruolei Xin ◽

Weiping Cai ◽

Xizi Deng ◽

Linghua Li ◽

...

Keyword(s):

Drug Resistance ◽

Drug Susceptibility ◽

Public Health Issue ◽

Resistance Mutations ◽

Acquired Drug Resistance ◽

Low Level ◽

High Level ◽

Hiv 1 ◽

Level Resistance ◽

Epidemiological Information

Abstract Background HIV-1 acquired drug resistance (ADR) has become a critical clinical and public health issue. Recently, HIV-1 CRF55_01B has been found more frequently in the MSM population. Objective To investigate the characteristics of HIV-1 drug resistance mutations (DRMs) and the extent of changes in drug susceptibility among ART-experienced CRF55_01B-infected adults of Guangdong. Methods ADR was tested for immediately in CRF55_01B-infected patients with virological failure. Demographic and epidemiological information was collected. DRMs and antiretroviral susceptibility were interpreted using the Stanford University HIV Drug Resistance Database HIVdb program. Results Overall, 162 (4.78%) CRF55_01B isolates were identified from 2013 to 2018. Among DRMs, M184V (43.83%) was the most frequent NRTI DRM, followed by K65R (23.46%), and V179E (98.77%) was the most frequent NNRTI DRM, followed by K103N (47.53%) and Y181C (14.81%). According to the HIVdb program, 79.01% of the CRF55_01B-infected patients carried mutations conferring low-level or higher drug resistance to any of the three classes of ART drugs. Among PI DRMs, only one mutation affording low-level resistance to nelfinavir was found (0.62%). Among NRTI DRMs, a high proportion of high-level resistance to lamivudine (58.64%) and emtricitabine (58.02%) was found. As regards NNRTIs, more than 75% of patients carried efavirenz and nevirapine DRMs. The percentages of high-level resistance were 70.99%, 63.58%, 22.22%, 17.90% and 4.32% for nevirapine, efavirenz, rilpivirine, doravirine and etravirine, respectively. Conclusions High frequencies of DRMs and resistance were observed among CRF55_01B-infected patients failing ART in Guangdong, and interventions may be considered to minimize ecological contributions to ART.

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Dolutegravir Monotherapy of Simian Immunodeficiency Virus-Infected Macaques Selects for Several Patterns of Resistance Mutations with Variable Virological Outcomes

Journal of Virology ◽

10.1128/jvi.01189-18 ◽

2018 ◽

Vol 93 (2) ◽

Cited By ~ 4

Author(s):

Koen K. A. Van Rompay ◽

Said Hassounah ◽

Brandon F. Keele ◽

Jeffrey D. Lifson ◽

Amir Ardeshir ◽

...

Keyword(s):

Drug Resistance ◽

Chronic Infection ◽

Resistance Mutations ◽

Infected People ◽

Low Level ◽

Immunodeficiency Virus ◽

Drug Regimens ◽

Hiv 1 ◽

Level Resistance

ABSTRACT Drug resistance remains a major concern for human immunodeficiency virus (HIV) treatment. To date, very few resistance mutations have emerged in first-line combination therapy that includes the integrase strand transfer inhibitor (INSTI) dolutegravir (DTG). In vitro, DTG selects for several primary mutations that induce low-level DTG resistance; secondary mutations, while increasing the level of resistance, however, further impair replication fitness, which raised the idea that DTG monotherapy may be feasible. The simian immunodeficiency virus (SIV) rhesus macaque model of HIV infection can be useful to explore this concept. Nine macaques were infected with virulent SIVmac251 and started on DTG monotherapy during either acute (n = 2) or chronic infection (n = 7). Within 4 weeks of treatment, all animals demonstrated a reduction in viremia of 0.8 to 3.5 log RNA copies/ml plasma. Continued treatment led to overall sustained benefits, but the outcome after 10 to 50 weeks of treatment was highly variable and ranged from viral rebound to near pretreatment levels to sustained suppression, with viremia being 0.5 to 5 logs lower than expected based on pretreatment viremia. A variety of mutations previously described to confer low-level resistance of HIV-1 to DTG or other INSTI were detected, and these were sometimes followed by mutations believed to be compensatory. Some mutations, such as G118R, previously shown to severely impair the replication capacity in vitro, were associated with more sustained virological and immunological benefits of continued DTG therapy, while other mutations, such as E92Q and G140A/Q148K, were associated with more variable outcomes. The observed variability of the outcomes in macaques warrants avoidance of DTG monotherapy in HIV-infected people. IMPORTANCE A growing number of anti-HIV drug combinations are effective in suppressing virus replication in HIV-infected persons. However, to reduce their cost and risk for toxicity, there is considerable interest in simplifying drug regimens. A major concern with single-drug regimens is the emergence of drug-resistant viral mutants. It has been speculated that DTG monotherapy may be a feasible option, because DTG may have a higher genetic barrier for the development of drug resistance than other commonly used antiretrovirals. To explore treatment initiation with DTG monotherapy, we started SIV-infected macaques on DTG during either acute or chronic infection. Although DTG initially reduced virus replication, continued treatment led to the emergence of a variety of viral mutations previously described to confer low-level resistance of HIV-1 to DTG, and this was associated with variable clinical outcomes. This unpredictability of mutational pathways and outcomes warns against using DTG monotherapy as initial treatment for HIV-infected people.

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Reduced efficacy of HIV-1 integrase inhibitors in patients with drug resistance mutations in reverse transcriptase

10.21203/rs.3.rs-45647/v1 ◽

2020 ◽

Author(s):

Mark Siedner ◽

Michelle Moorhouse ◽

Brioni Simmons ◽

Tulio de Oliveira ◽

Richard Lessells ◽

...

Keyword(s):

Drug Resistance ◽

Reverse Transcriptase ◽

Treatment Initiation ◽

World Health ◽

Integrase Inhibitors ◽

Resistance Mutations ◽

First Line ◽

Nnrti Resistance ◽

The Impact ◽

Hiv 1

Abstract Background: Little is known about the impact of pre-treatment drug resistance (PDR) to non-nucleoside reverse transcriptase inhibitors (NNRTIs) on the efficacy of second generation integrase inhibitors, now the standard of care drug class for HIV-1 treatment globally.Methods: We conducted next-generation sequencing on stored plasma specimens from the ADVANCE trial collected prior to treatment initiation. Our primary outcome was 96-week virologic success, defined as achievement of a viral load < 1000 copies/mL from 12 weeks, < 200 copies/mL from 24 weeks, and < 50 copies/mL from 48 through 96 weeks. We estimated the impact of PDR, defined by the presence of drug resistance on the World Health Organization (WHO) mutation list, on virologic outcomes in the entire cohort, and stratified by EFV-based versus DTG-based regimens. In sensitivity analyses, we allowed virologic failure with re-suppression, assessed FDA 48 and 96-week Snapshot outcomes, and considered minority resistance mutations (5–20% frequency).Results: Of 1,053 trial participants, 873 (83%) had plasma available and successful sequencing completed. Of these, 288 (33%) were randomized to an EFV-based regimen and 585 (67%) were randomized to a DTG-based regimen. Fourteen percent (122/873) had at least one WHO-defined mutation, of which over 98% (120/122) had NNRTI mutations. NRTI mutations were rare (20/873, 2%). Rates of virologic suppression were significantly lower in those with PDR 65% (73/112) compared to those without PDR (85% [605/713], P < 0.001). This phenomenon was consistent for both EFV-based (60% [12/20] versus 86% [214/248], P = 0.002) and DTG-based ART (61/92 [66%] versus 84% [391/465] P < 0.001, P for interaction by regimen 0.49). In multivariable models adjusted for clinical characteristics and treatment adherence, PDR strongly predicted failure [adjusted OR 0.38 (0.23–0.61), P < 0.001]. Although suppression rates were greater when allowing for non-consecutive visits with failure, PDR significantly predicted greater risk of failure for both regimens in all outcome definitions. We found no effect of mutations at frequencies 5–20% on any of our outcomes.Interpretation: NNRTI resistance prior to treatment initiation is associated with failure of integrase inhibitor-containing first-line regimens. These results portend high rates of first-line treatment failure in sub Saharan Africa, where circulating NNRTI resistance is common.

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Genetic Diversity and Drug Resistance of HIV-1 CRF55_01B in Guangdong, China

Current HIV Research ◽

10.2174/1570162x18666200415140652 ◽

2020 ◽

Vol 18 (3) ◽

pp. 210-218

Author(s):

Guolong Yu ◽

Yan Li ◽

Xuhe Huang ◽

Pingping Zhou ◽

Jin Yan ◽

...

Keyword(s):

Genetic Diversity ◽

Drug Resistance ◽

Reverse Transcriptase ◽

Phylogenetic Analyses ◽

Resistance Mutations ◽

Protease Inhibition ◽

Subtype B ◽

Primary Drug Resistance ◽

Hiv 1 ◽

Primary Drug

Background: HIV-1 CRF55_01B was first reported in 2013. At present, no report is available regarding this new clade’s polymorphisms in its functionally critical regions protease and reverse transcriptase. Objective: To identify the diversity difference in protease and reverse transcriptase between CRF55_01B and its parental clades CRF01_AE and subtype B; and to investigate CRF55_01B’s drug resistance mutations associated with the protease inhibition and reverse transcriptase inhibition. Methods: HIV-1 RNA was extracted from plasma derived from a MSM population. The reverse transcription and nested PCR amplification were performed following our in-house PCR procedure. Genotyping and drug resistant-associated mutations and polymorphisms were identified based on polygenetic analyses and the usage of the HIV Drug Resistance Database, respectively. Results: A total of 9.24 % of the identified CRF55_01B sequences bear the primary drug resistance. CRF55_01B contains polymorphisms I13I/V, G16E and E35D that differ from those in CRF01_AE. Among the 11 polymorphisms in the RT region, seven were statistically different from CRF01_AE’s. Another three polymorphisms, R211K (98.3%), F214L (98.3%), and V245A/E (98.3 %.), were identified in the RT region and they all were statistically different with that of the subtype B. The V179E/D mutation, responsible for 100% potential low-level drug resistance, was found in all CRF55_01B sequences. Lastly, the phylogenetic analyses demonstrated 18 distinct clusters that account for 35% of the samples. Conclusions: CRF55_01B’s pol has different genetic diversity comparing to its counterpart in CRF55_01B’s parental clades. CRF55_01B has a high primary drug resistance presence and the V179E/D mutation may confer more vulnerability to drug resistance.

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Diversity of HIV-1 subtypes and transmitted drug-resistance mutations among minority HIV-1 variants in a Turkish cohort

Current HIV Research ◽

10.2174/1570162x19666211119111740 ◽

2021 ◽

Vol 19 ◽

Author(s):

Rabia Can Sarinoglu ◽

Uluhan Sili ◽

Ufuk Hasdemir ◽

Burak Aksu ◽

Guner Soyletir ◽

...

Keyword(s):

Drug Resistance ◽

Reverse Transcriptase ◽

Transcriptase Inhibitor ◽

Transmitted Drug Resistance ◽

Resistance Mutations ◽

Drug Resistance Mutations ◽

Subtype B ◽

Treatment Naïve ◽

Reverse Transcriptase Inhibitor ◽

Hiv 1

Background: The World Health Organization (WHO) recommends the surveillance of transmitted drug resistance mutations (TDRMs) to ensure the effectiveness and sustainability of HIV treatment programs. Objective: Our aim was to determine the TDRMs and evaluate the distribution of HIV-1 subtypes using and compared next-generation sequencing (NGS) and Sanger-based sequencing (SBS) in a cohort of 44 antiretroviral treatment-naïve patients. Methods: All samples that were referred to the microbiology laboratory for HIV drug resistance analysis between December 2016 and February 2018 were included in the study. After exclusions, 44 treatment-naive adult patients with a viral load of >1000 copies/mL were analyzed. DNA sequencing for reverse transcriptase and protease regions was performed using both DeepChek ABL single round kit and Sanger-based ViroSeq HIV-1 Genotyping System. The mutations and HIV-1 subtypes were analyzed using the Stanford HIVdb version 8.6.1 Genotypic Resistance software, and TDRMs were assessed using the WHO surveillance drug-resistance mutation database. HIV-1 subtypes were confirmed by constructing a maximum-likelihood phylogenetic tree using Los Alamos IQ-Tree software. Results: NGS identified nucleos(t)ide reverse transcriptase inhibitor (NRTI)-TDRMs in 9.1% of the patients, non-nucleos(t)ide reverse transcriptase inhibitor (NNRTI)-TDRMs in 6.8% of the patients, and protease inhibitor (PI)-TDRMs in 18.2% of the patients at a detection threshold of ≥1%. Using SBS, 2.3% and 6.8% of the patients were found to have NRTI- and NNRTI-TDRMs, respectively, but no major PI mutations were detected. M41L, L74I, K65R, M184V, and M184I related to NRTI, K103N to NNRTI, and N83D, M46I, I84V, V82A, L24I, L90M, I54V to the PI sites were identified using NGS. Most mutations were found in low-abundance (frequency range: 1.0% - 4.7%) HIV-1 variants, except M41L and K103N. The subtypes of the isolates were found as follows; 61.4% subtype B, 18.2% subtype B/CRF02_AG recombinant, 13.6% subtype A, 4.5% CRF43_02G, and 2.3% CRF02_AG. All TDRMs, except K65R, were detected in HIV-1 subtype B isolates.. Conclusion: The high diversity of protease site TDRMs in the minority HIV-1 variants and prevalence of CRFs were remarkable in this study. All minority HIV-1 variants were missed by conventional sequencing. TDRM prevalence among minority variants appears to be decreasing over time at our center.

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L74V increases the reverse transcriptase content of HIV-1 virions with non-nucleoside reverse transcriptase drug-resistant mutations L100I+K103N and K101E+G190S, which results in increased fitness

Journal of General Virology ◽

10.1099/vir.0.050914-0 ◽

2013 ◽

Vol 94 (7) ◽

pp. 1597-1607 ◽

Cited By ~ 3

Author(s):

Jiong Wang ◽

Dongge Li ◽

Robert A. Bambara ◽

Hongmei Yang ◽

Carrie Dykes

Keyword(s):

Reverse Transcriptase ◽

Resistance Mutation ◽

Transcriptase Inhibitor ◽

Rnase H ◽

Drug Resistant ◽

Resistance Mutations ◽

Nnrti Resistance ◽

Reverse Transcriptase Inhibitor ◽

Subsequent Addition ◽

Hiv 1

The fitness of non-nucleoside reverse transcriptase inhibitor (NNRTI) drug-resistant reverse transcriptase (RT) mutants of HIV-1 correlates with the amount of RT in the virions and the RNase H activity of the RT. We wanted to understand the mechanism by which secondary NNRTI-resistance mutations, L100I and K101E, and the nucleoside resistance mutation, L74V, alter the fitness of K103N and G190S viruses. We measured the amount of RT in virions and the polymerization and RNase H activities of mutant RTs compared to wild-type, K103N and G190S. We found that L100I, K101E and L74V did not change the polymerization or RNase H activities of K103N or G190S RTs. However, L100I and K101E reduced the amount of RT in the virions and subsequent addition of L74V restored RT levels back to those of G190S or K103N alone. We conclude that fitness changes caused by L100I, K101E and L74V derive from their effects on RT content.

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Silent mutations at codons 65 and 66 in reverse transcriptase alleviate indel formation and restore fitness in subtype B HIV-1 containing D67N and K70R drug resistance mutations

Nucleic Acids Research ◽

10.1093/nar/gkv128 ◽

2015 ◽

Vol 43 (6) ◽

pp. 3256-3271 ◽

Cited By ~ 6

Author(s):

Sushama Telwatte ◽

Anna C. Hearps ◽

Adam Johnson ◽

Catherine F. Latham ◽

Katie Moore ◽

...

Keyword(s):

Drug Resistance ◽

Reverse Transcriptase ◽

Resistance Mutations ◽

Drug Resistance Mutations ◽

Subtype B ◽

Hiv 1

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Two Coselected Distal Mutations in HIV-1 Reverse Transcriptase (RT) Alter Susceptibility to Nonnucleoside RT Inhibitors and Nucleoside Analogs

Journal of Virology ◽

10.1128/jvi.00224-19 ◽

2019 ◽

Vol 93 (11) ◽

Author(s):

Paul L. Boyer ◽

Kevin Melody ◽

Steven J. Smith ◽

Linda L. Dunn ◽

Chris Kline ◽

...

Keyword(s):

Nucleic Acid ◽

Reverse Transcriptase ◽

Active Site ◽

Nucleoside Analogs ◽

Transcriptase Inhibitor ◽

Drug Resistant ◽

Resistance Mutations ◽

Hydrophobic Region ◽

Nnrti Resistance ◽

Hiv 1

ABSTRACTTwo mutations, G112D and M230I, were selected in the reverse transcriptase (RT) of human immunodeficiency virus type 1 (HIV-1) by a novel nonnucleoside reverse transcriptase inhibitor (NNRTI). G112D is located near the HIV-1 polymerase active site; M230I is located near the hydrophobic region where NNRTIs bind. Thus, M230I could directly interfere with NNRTI binding but G112D could not. Biochemical and virological assays were performed to analyze the effects of these mutations individually and in combination. M230I alone caused a reduction in susceptibility to NNRTIs, while G112D alone did not. The G112D/M230I double mutant was less susceptible to NNRTIs than was M230I alone. In contrast, both mutations affected the ability of RT to incorporate nucleoside analogs. We suggest that the mutations interact with each other via the bound nucleic acid substrate; the nucleic acid forms part of the polymerase active site, which is near G112D. The positioning of the nucleic acid is influenced by its interactions with the “primer grip” region and could be influenced by the M230I mutation.IMPORTANCEAlthough antiretroviral therapy (ART) is highly successful, drug-resistant variants can arise that blunt the efficacy of ART. New inhibitors that are broadly effective against known drug-resistant variants are needed, although such compounds might select for novel resistance mutations that affect the sensitivity of the virus to other compounds. Compound 13 selects for resistance mutations that differ from traditional NNRTI resistance mutations. These mutations cause increased sensitivity to NRTIs, such as AZT.

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Prevalence of integrase strand transfer inhibitor resistance mutations in antiretroviral-naive HIV-1-infected individuals in Cameroon

Journal of Antimicrobial Chemotherapy ◽

10.1093/jac/dkaa383 ◽

2020 ◽

Vol 76 (1) ◽

pp. 124-129

Author(s):

Benjamin M Wenk ◽

Herbert A Mbunkah ◽

Ndi N Nsanwe ◽

Eyongetah T Mbu ◽

Lydia M Besong ◽

...

Keyword(s):

Drug Resistance ◽

Universal Primers ◽

Polymorphism Analysis ◽

Strand Transfer ◽

Resistance Mutations ◽

Transfer Inhibitor ◽

Study Sites ◽

Inhibitor Resistance ◽

The Impact ◽

Hiv 1

Abstract Objectives In Cameroon, the integrase (IN) strand transfer inhibitor (INSTI) dolutegravir was recently introduced for the treatment of HIV-1 infection. Since pretreatment HIV-1 drug resistance can jeopardize the success of ART, and considering the high heterogeneity of circulating HIV-1 subtypes in Cameroon, we investigated the prevalence of pretreatment HIV-1 resistance to INSTIs. Methods Fingerprick dried blood spot samples were collected from 339 newly diagnosed HIV-1-infected individuals between 2015 and 2016 in four hospitals in Cameroon. Universal primers were designed to amplify the HIV-1 IN region from amino acid 1 to 276. Amplicons were sequenced with Illumina next-generation sequencing and analysed with the Polymorphism Analysis Sequencing (PASeq) platform, using the Stanford HIV Drug Resistance Database to interpret HIV-1 drug resistance mutations (DRMs). Results The amplification/sequencing success rate was 75.2% with 255/339 sequences obtained. Applying a cut-off of 1%, major DRMs to INSTIs were detected in 13 (5.1%) individuals, but only 1 individual harboured an INSTI DRM (E92G) at a nucleotide frequency ≥15%. However, 140/255 (54.9%) individuals harboured polymorphic accessory INSTI DRMs, mainly at high frequencies. In line with that observation, HIV-1 subtype diversity among individuals was high. Conclusions Pretreatment HIV-1 resistance to INSTIs was low in the study sites, which supports the use of INSTIs in Cameroon. Nevertheless, further studies are necessary to assess the impact of polymorphic accessory INSTI DRMs on INSTI-based ART regimens.

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