scholarly journals Frequency of capsid substitutions associated with GS-6207 in vitro resistance in HIV-1 from antiretroviral-naive and -experienced patients

2020 ◽  
Vol 75 (6) ◽  
pp. 1588-1590
Author(s):  
Anne-Geneviève Marcelin ◽  
Charlotte Charpentier ◽  
Aude Jary ◽  
Marine Perrier ◽  
Nicolas Margot ◽  
...  
Keyword(s):  
In Vitro Selection ◽  
Phase 1 ◽  
People Living With Hiv ◽  
Resistance Mutations ◽  
Nuclear Entry ◽  
Particle Assembly ◽  
Phenotypic Resistance ◽  
Capsid Formation ◽  
Long Acting

Abstract Background GS-6207 is a first-in-class HIV capsid inhibitor, targeting several functions of the HIV capsid in the viral cycle, including viral particle assembly, capsid formation and nuclear entry. GS-6207 has demonstrated picomolar potency in vitro, activity confirmed by high potency in a Phase 1 clinical study, with a long-acting antiretroviral profile with potential dosing every 6 months. In vitro resistance selections previously conducted with increasing doses of GS-6207 have identified capsid variants with reduced susceptibility to GS-6207. Objectives To study the prevalence of capsid mutations associated with in vitro resistance to GS-6207 in people living with HIV (PLWH). Methods Plasma samples from ART-naive or -experienced PLWH, including PI-experienced people, were sequenced and analysed for the presence of capsid variants identified during in vitro resistance selection: L56I, M66I, Q67H, K70N, N74D, N74S and T107N. Results Among the samples from the 1500 patients studied, none of the seven GS-6207 resistance mutations identified during in vitro selection experiments was detected, regardless of HIV subtype or PLWH treatment history. Conclusions Out of the seven HIV capsid substitutions previously selected in vitro and shown to confer phenotypic resistance to GS-6207, none of these seven mutations was observed in this large dataset, suggesting that neither PLWH with previous PI failure nor PLWH with emergence of PI resistance mutations are anticipated to impact GS-6207 activity in these diverse HIV-infected populations.

scholarly journals Absence of Lenacapavir (GS-6207) Phenotypic Resistance in HIV Gag Cleavage Site Mutants and in Isolates with Resistance to Existing Drug Classes

2020 ◽  
Author(s):  
Nicolas Margot ◽  
Renee Ram ◽  
Martin Rhee ◽  
Christian Callebaut
Keyword(s):  
Cleavage Site ◽  
Fold Change ◽  
People Living With Hiv ◽  
Wild Type ◽  
Resistance Mutations ◽  
Phenotypic Resistance ◽  
Control Drug ◽  
Drug Classes ◽  
Long Acting ◽  
Hiv 1

Lenacapavir (LEN, GS-6207) is a potent, first-in-class inhibitor of HIV-1 capsid with long-acting properties and the potential for subcutaneous dosing every 3 months or longer. In the clinic, a single subcutaneous LEN injection (20 mg to 750 mg) in people-living-with-HIV (PLWH) showed a strong antiviral response, with a >2.3 mean log10 decrease in HIV-1 RNA at day 10. HIV-1 Gag mutations near protease (PR) cleavage sites have emerged with the use of protease inhibitors (PIs). Here we have characterized the activity of LEN in mutants with Gag cleavage site mutations (GCSMs), and mutants resistant to other drug classes. HIV mutations were inserted into the pXXLAI clone and the resulting mutants (n = 70) were evaluated using a 5-day antiviral assay. LEN EC50 fold change versus wild-type ranged from 0.4 to 1.9 in these mutants, similar to the control drug. In contrast, reduced susceptibility to PIs and maturation inhibitors (MIs) was observed. Testing of isolates with resistance against the 4 main classes of drugs (n = 40) indicated wild-type susceptibility to LEN (fold change ranging from 0.3 to 1.1), while reduced susceptibility was observed for control drugs. HIV GCSMs did not impact the activity of LEN, while some conferred resistance to MIs and PIs. Similarly, LEN activity was not affected by naturally-occurring variations in HIV Gag, in contrast to the reduced susceptibility observed for MIs. Finally, the activity of LEN was not affected by the presence of resistance mutations to the 4 main ARV classes. These data support the evaluation of LEN in PLWH with multi-class resistance.

scholarly journals In Vitro Selection of Clinically Relevant Bevirimat Resistance Mutations Revealed by "Deep" Sequencing of Serially Passaged, Quasispecies-Containing Recombinant HIV-1

2010 ◽  
Vol 49 (1) ◽  
pp. 201-208 ◽  
Author(s):  
D. J. H. F. Knapp ◽  
P. R. Harrigan ◽  
A. F. Y. Poon ◽  
Z. L. Brumme ◽  
M. Brockman ◽  
...  
Keyword(s):  
Deep Sequencing ◽  
In Vitro Selection ◽  
Resistance Mutations ◽  
Hiv 1 ◽  
Selection Of

scholarly journals In vitro analysis of human immunodeficiency virus type 1 resistance to nevirapine and fitness determination of resistant variants

2002 ◽  
Vol 83 (1) ◽  
pp. 93-101 ◽  
Author(s):  
Maria Dolores Iglesias-Ussel ◽  
Concepción Casado ◽  
Eloísa Yuste ◽  
Isabel Olivares ◽  
Cecilio López-Galíndez
Keyword(s):  
Fold Increase ◽  
Resistant Mutant ◽  
Wild Type ◽  
Resistance Mutations ◽  
Phenotypic Resistance ◽  
Drug Concentrations ◽  
Immunodeficiency Virus ◽  
Vitro Analysis

Nevirapine-resistant variants were generated by serial passages in MT-2 cells in the presence of increasing drug concentrations. In passage 5, mutations V106A, Y181C and G190A were detected in the global population, associated with a 100-fold susceptibility decrease. Sequence analysis of biological clones obtained from passage 5 and subsequent passages showed that single mutants, detected in first passages, were progressively replaced in passage 15 by double mutants, correlating with a 500-fold increase in phenotypic resistance. Fitness determination of single mutants confirmed that, in the presence of nevirapine, every variant was more fit than wild-type with a fitness order Y181C>V106A>G190A>wild-type. Unexpectedly, in the absence of the drug, the Y181C resistant mutant was more fit than wild-type, with a fitness gradient Y181C>wild-type >G106A⩾V190A. Using a molecular clone in which the Y181C mutation was introduced by in vitro mutagenesis, the greater fitness of the Y181C mutant was confirmed in new competition cultures. These data exemplify the role of resistance mutations on virus phenotype but also on virus evolution leading, occasionally, to resistant variants fitter than the wild-type in the absence of the drug.

scholarly journals Viral Determinants of Resistance to Treatment in Patients with Hepatitis C

2007 ◽  
Vol 20 (1) ◽  
pp. 23-38 ◽  
Author(s):  
Anette Wohnsland ◽  
Wolf Peter Hofmann ◽  
Christoph Sarrazin
Keyword(s):  
Hepatitis C ◽  
Antiviral Therapy ◽  
Phase 1 ◽  
Treatment Success ◽  
Antiviral Agents ◽  
Antiviral Drugs ◽  
Immune Defense ◽  
Phenotypic Resistance

SUMMARY Chronic hepatitis C virus (HCV) infection affects more than 170 million persons worldwide and is responsible for the development of liver cirrhosis in many cases. Standard treatment with pegylated alpha interferon (IFN-α) in combination with the nucleoside analogue ribavirin leads to a sustained virologic response in approximately half of the patients. IFN-α is classified as an indirect treatment, as it interacts with the host's immune response. The mechanism of action of ribavirin is still unknown. The benefit of triple therapy by adding other antiviral agents, e.g., amantadine, is controversial. Currently, new direct antiviral drugs (HCV protease/polymerase inhibitors) are being evaluated in phase 1/phase 2 trials. Phenotypic resistance to antiviral therapy has been attributed to amino acid variations within distinct regions of the HCV polyprotein. While sensitivity to IFN-α-based antiviral therapy in vivo is clearly correlated with the number of mutations within the HCV NS5A protein, the underlying functional mechanisms for this association are unknown. In turn, in vitro, several mechanisms to circumvent the host immune defense or to block treatment-induced antiviral activities have been described for different HCV proteins. By the introduction of direct antiviral drugs, hepatitis C therapy now is entering a new era in which the development of resistance may become the most important parameter for treatment success or failure.

scholarly journals Convergent In Vivo and In Vitro Selection of Ceftazidime Resistance Mutations at Position 167 of CTX-M-3 β-Lactamase in Hypermutable Escherichia coli Strains

2008 ◽  
Vol 52 (4) ◽  
pp. 1297-1301 ◽  
Author(s):  
Marina N. Stepanova ◽  
Maxim Pimkin ◽  
Anatoly A. Nikulin ◽  
Varvara K. Kozyreva ◽  
Elena D. Agapova ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Molecular Typing ◽  
In Vitro Selection ◽  
Resistance Mutations ◽  
Natural Evolution ◽  
E Coli ◽  
Low Activity ◽  
Selection Of

ABSTRACT We report on a novel CTX-M extended-spectrum β-lactamase (ESBL), designated CTX-M-42, with enhanced activity toward ceftazidime. CTX-M-42 was identified in a hypermutable Escherichia coli nosocomial isolate (isolate Irk2320) and is a Pro167Thr amino acid substitution variant of CTX-M-3. By molecular typing of ESBL-producing E. coli strains previously isolated in the same hospital ward, we were able to identify a putative progenitor (strain Irk1224) of Irk2320, which had a mutator phenotype and harbored the CTX-M-3 β-lactamase. To reproduce the natural evolution of CTX-M-3, we selected for ceftazidime resistance mutations in bla CTX-M-3 gene in vitro both in clinical isolate Irk1224 and in laboratory-derived hypermutable (mutD5) strain GM2995. These experiments yielded CTX-M-3Pro167Ser and CTX-M-3Asn136Lys mutants which conferred higher levels of resistance to ceftazidime than to cefotaxime. CTX-M-3Asn136Lys had a level of low activity toward ampicillin, which may explain its absence from clinical isolates. We conclude that the selection of CTX-M-42 could have occurred in vivo following treatment with ceftazidime and was likely facilitated by the hypermutable background.

scholarly journals A combined computational and experimental strategy identifies mutations conferring resistance to drugs targeting the BCR-ABL fusion protein

2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Jinxin Liu ◽  
Jianfeng Pei ◽  
Luhua Lai
Keyword(s):  
Drug Resistance ◽  
In Vitro Selection ◽  
Binding Constants ◽  
Computational Prediction ◽  
Resistance Mutations ◽  
Experimental Strategy ◽  
Drug Resistance Mutations ◽  
Suggested Strategy

AbstractDrug resistance is of increasing concern, especially during the treatments of infectious diseases and cancer. To accelerate the drug discovery process in combating issues of drug resistance, here we developed a computational and experimental strategy to predict drug resistance mutations. Using BCR-ABL as a case study, we successfully recaptured the clinically observed mutations that confer resistance imatinib, nilotinib, dasatinib, bosutinib, and ponatinib. We then experimentally tested the predicted mutants in vitro. We found that although all mutants showed weakened binding strength as expected, the binding constants alone were not a good indicator of drug resistance. Instead, the half-maximal inhibitory concentration (IC50) was shown to be a good indicator of the incidence of the predicted mutations, together with change in catalytic efficacy. Our suggested strategy for predicting drug-resistance mutations includes the computational prediction and in vitro selection of mutants with increased IC50 values beyond the drug safety window.

scholarly journals Correlation of molecular resistance mechanisms and phenotypic resistance levels in streptomycin-resistant Mycobacterium tuberculosis.

1996 ◽  
Vol 40 (11) ◽  
pp. 2452-2454 ◽  
Author(s):  
A Meier ◽  
P Sander ◽  
K J Schaper ◽  
M Scholz ◽  
E C Böttger
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Resistance Mechanism ◽  
Active Agent ◽  
Cross Resistance ◽  
Permeability Barrier ◽  
Wild Type ◽  
Resistance Mutations ◽  
Phenotypic Resistance ◽  
Level Resistance

Quantitative susceptibility testing of clinical isolates of streptomycin-resistant Mycobacterium tuberculosis demonstrated that there is a close correlation between the molecular resistance mechanism and the in vitro activity of streptomycin: mutations in rpsL were mainly associated with high-level resistance, mutations in rrs were associated with an intermediate level of resistance, and streptomycin-resistant isolates with wild-type rpsL and rrs exhibited a low-level resistance phenotype. Investigations of streptomycin-resistant isolates with wild-type rpsL and rrs revealed that (i) there is no cross-resistance to other drugs and (ii) a permeability barrier may contribute to resistance, because resistance was significantly lowered in the presence of a membrane-active agent.

scholarly journals Variations in Reverse Transcriptase and RNase H Domain Mutations in Human Immunodeficiency Virus Type 1 Clinical Isolates Are Associated with Divergent Phenotypic Resistance to Zidovudine

2007 ◽  
Vol 51 (11) ◽  
pp. 3861-3869 ◽  
Author(s):  
Michel Ntemgwa ◽  
Mark A. Wainberg ◽  
Maureen Oliveira ◽  
Daniela Moisi ◽  
Richard Lalonde ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Reverse Transcriptase ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Rnase H ◽  
Resistance Mutations ◽  
Phenotypic Resistance ◽  
Immunodeficiency Virus

ABSTRACT Mutations in the RNase H domain of human immunodeficiency virus type 1 RT have been reported to cause resistance to zidovudine (ZDV) in vitro. However, very limited data on the in vivo relevance of these mutations in patients exist to date. This study was designed to determine the relationship between mutations in the RNase H domain and viral susceptibility to nucleoside analogues. Viruses harboring complex thymidine analogue mutation (TAM) and nucleoside analogue mutation (NAM) profiles were evaluated for their phenotypic susceptibilities to ZDV, tenofovir (TNF), and the nonapproved nucleoside reverse transcriptase inhibitors (NRTIs) β-2′,3′-didehydro-2′,3′-dideoxy-5-fluorocytidine (Reverset), β-d-5-fluorodioxolane-cytosine, and apricitabine. As controls, viruses from NRTI-naïve patients were also studied. The pol RT region (codons 21 to 250) of the viruses were sequenced and evaluated for mutations in the RNase H domain (codons 441 to 560) and the connection domain (codons 289 to 400). The results showed that viruses from patients failing multiple NRTI-containing regimens had distinct TAM and NAM profiles that conferred various degrees of resistance to ZDV (0.9- to >300-fold). Sequencing of the RNase H domain identified five positions (positions 460,468, 483, 512, and 519) at which extensive amino acid polymorphisms common in both wild-type viruses and viruses from treated patients were identified. No mutations were observed at positions 539 and 549, which have previously been associated with ZDV resistance. Mutations in the RNase H domain did not appear to correlate with the levels of phenotypic resistance to ZDV. Although some mutations were also observed in the connection domain, the simultaneous presence of the L74V and M184V mutations was the most significant determinant of phenotypic resistance to ZDV in patients infected with viruses with TAMs.

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