The impact of the nelfinavir resistance-conferring mutation D30N on the susceptibility of HIV-1 subtype B to other protease inhibitors (original) (raw)
Related papers
HIV-1 genotypes related to failure of nelfinavir as the first protease inhibitor treatment
Brazilian Journal of Infectious Diseases, 2005
Combined antiretroviral therapy results in sustained viral suppression and a decrease in mortality and morbidity due to HIV infection. Intrinsic strength, durability and absence of crossresistance are key factors in the selection of antiretrovirals. Failure with nelfinavir has been associated with two protease gene mutations, D30N and L90M. The D30N mutation does not result in cross-resistance with other protease inhibitors, and it decreases viral fitness. In order to check for this mutation after failure with nelfinavir, the 246 HIV-1 genotyping test was performed on virus samples from 55 patients with failure of nelfinavir as the first protease inhibitor. Most (84%) of the viral strains were of subtype B. Nucleosides associated with mutations (NAM) were observed in 80% of the tests; no INS69, complex 151, K65R and L74V mutations, which give multi-resistance to nucleoside analogue reverse transcriptase inhibitors to tenofovir and DDI, respectively, were observed. In the tests for protease gene mutations, the D30N mutation was found in 57%, L90M in 18% and the wild-type virus in 25%. These data are similar to published reports, showing that alternative therapies used after failure with nelfinavir may be more successful, as the D30N mutation does not cause cross-resistance to other protease inhibitors.
AIDS Research and Human Retroviruses, 2006
Nelfinavir was once one of the most commonly used protease inhibitors (PIs). To investigate the genetic mechanisms of multidrug resistance in protease isolates with the primary nelfinavir resistance mutation D30N, we analyzed patterns of protease mutations in 582 viruses with D30N from 460 persons undergoing HIV-1 genotypic resistance testing at Stanford University Hospital from 1997 to 2005. Three patterns of mutational associations were identified. First, D30N was positively associated with N88D but negatively associated with N88S. Second, D30N and L90M were negatively associated except in the presence of N88D, which facilitated the cooccurrence of D30N and L90M. Third, D30N + N88D + L90M formed a stable genetic backbone for the accumulation of additional protease inhibitor (PI) resistance mutations. In 16 patients having isolates with more than one combination of mutations at positions 30, 88, and 90, all exhibited one of the steps in the following progression: D30N → D30N + N88D → D30N + N88D + L90M → D30N + N88D + L90M + (L33F ± I84V or M46I/L ± I54V). Although nelfinavir is now used less frequently than other PIs, the well-delineated mutational pathway we describe is likely to influence patterns of crossresistance in viruses from persons who experience virologic failure while receiving this PI.
Journal of Virology, 2001
We examined the prevalence of cleavage site mutations, both within and outside the gag region, in 28 protease inhibitor (PI) cross-resistant patients treated with indinavir, ritonavir, and/or saquinavir compared to control patients treated with reverse transcriptase inhibitors. Three human immunodeficiency virus protease cleavage sites within gag (p2/NC, NC/p1, and NC/TFP) showed considerable in vivo evolution before and after therapy with indinavir, ritonavir, and/or saquinavir. Another gag cleavage site (p1/p6 gag ) showed a trend compared to matched controls. The other eight recognized cleavage sites showed relatively little difference between PI-resistant cases and controls. An A→V substitution at the P2 position of the NC/p1 and NC/TFP cleavage sites was the most common (29%) change selected by the PIs used in this study.
Antimicrobial Agents and Chemotherapy, 2004
Differences in baseline polymorphisms between subtypes may result in development of diverse mutational pathways during antiretroviral treatment. We compared drug resistance in patients with human immunodeficiency virus subtype C (referred to herein as "subtype-C-infected patients") versus subtype-B-infected patients following protease inhibitor (PI) therapy. Genotype, phenotype, and replication capacity (Phenosense; Virologic) were determined. We evaluated 159 subtype-C-and 65 subtype-B-infected patients failing first PI treatment. Following nelfinavir treatment, the unique nelfinavir mutation D30N was substantially less frequent in C (7%) than in B (23%; P ؍ 0.03) while L90M was similar (P < 0.5). Significant differences were found in the rates of M36I (98 and 36%), L63P (35 and 59%), A71V (3 and 32%), V77I (0 and 36%), and I93L (91 and 32%) (0.0001 < P < 0.05) in C and B, respectively. Other mutations were L10I/V, K20R, M46I, V82A/I, I84V, N88D, and N88S. Subtype C samples with mutation D30N showed a 50% inhibitory concentration (IC 50 ) change in susceptibility to nelfinavir only. Other mutations increased IC 50 correlates to all PIs. Following accumulation of mutations, replication capacity of the C virus was reduced from 43% ؎ 22% to 22% ؎ 15% (P ؍ 0.04). We confirmed the selective nature of the D30N mutation in C, and the broader cross-resistance of other common protease inhibitor mutations. The rates at which these mutational pathways develop differ in C and subtype-B-infected patients failing therapy, possibly due to the differential impact of baseline polymorphisms. Because mutation D30N is not preferentially selected in nelfinavir-treated subtype-C-infected patients, as it is in those infected with subtype B, the consideration of using this drug initially to preserve future protease inhibitor options is less relevant for subtype-C-infected patients.
Antimicrobial Agents and Chemotherapy, 2010
The amino acid at position 36 of the HIV-1 protease differs among various viral subtypes, in that methionine is usually found in subtype B viruses but isoleucine is common in other subtypes. This polymorphism is associated with higher rates of treatment failure involving protease inhibitors (PIs) in non-subtype B-infected patients. To investigate this, we generated genetically homogeneous wild-type viruses from subtype B, subtype C, and CRF02_AG full-length molecular clones and showed that subtype C and CRF02_AG I36 viruses exhibited higher levels of resistance to various PIs than their respective M36 counterparts, while the opposite was observed for subtype B viruses. Selections for resistance with each variant were performed with nelfinavir (NFV), lopinavir (LPV), and atazanavir (ATV). Sequence analysis of the protease gene at week 35 revealed that the major NFV resistance mutation D30N emerged in NFV-selected subtype B viruses and in I36 subtype C viruses, despite polymorphic variation. A unique mutational pattern developed in subtype C M36 viruses selected with NFV or ATV. The presence of I47A in LPV-selected I36 CRF02_AG virus conferred higher-level resistance than L76V in LPV-selected M36 CRF02_AG virus. Phenotypic analysis revealed a >1,000-fold increase in NFV resistance in I36 subtype C NFV-selected virus with no apparent impact on viral replication capacity. Thus, the position 36 polymorphism in the HIV-1 protease appears to have a differential effect on both drug susceptibility and the viral replication capacity, depending on both the viral subtype and the drug being evaluated.
HIV-1 Protease Mutations and Protease Inhibitor Cross-Resistance
Antimicrobial Agents and Chemotherapy, 2010
The effects of many protease inhibitor (PI)-selected mutations on the susceptibility to individual PIs are unknown. We analyzed in vitro susceptibility test results on 2,725 HIV-1 protease isolates. More than 2,400 isolates had been tested for susceptibility to fosamprenavir, indinavir, nelfinavir, and saquinavir; 2,130 isolates had been tested for susceptibility to lopinavir; 1,644 isolates had been tested for susceptibility to atazanavir; 1,265 isolates had been tested for susceptibility to tipranavir; and 642 isolates had been tested for susceptibility to darunavir. We applied least-angle regression (LARS) to the 200 most common mutations in the data set and identified a set of 46 mutations associated with decreased PI susceptibility of which 40 were not polymorphic in the eight most common HIV-1 group M subtypes. We then used least-squares regression to ascertain the relative contribution of each of these 46 mutations. The median number of mutations associated with decreased susceptibility to each PI was 28 (range, 19 to 32), and the median number of mutations associated with increased susceptibility to each PI was 2.5 (range, 1 to 8). Of the mutations with the greatest effect on PI susceptibility, I84AV was associated with decreased susceptibility to eight PIs; V32I, G48V, I54ALMSTV, V82F, and L90M were associated with decreased susceptibility to six to seven PIs; I47A, G48M, I50V, L76V, V82ST, and N88S were associated with decreased susceptibility to four to five PIs; and D30N, I50L, and V82AL were associated with decreased susceptibility to fewer than four PIs. This study underscores the greater impact of nonpolymorphic mutations compared with polymorphic mutations on decreased PI susceptibility and provides a comprehensive quantitative assessment of the effects of individual mutations on susceptibility to the eight clinically available PIs.
Drug Resistance Pathways and Impact of Protease Mutation L10I/V in HIV-1 Non-B Subtypes
Journal of Antivirals & Antiretrovirals, 2012
Background: Molecular pathways to drug resistance have yet to be fully characterized in HIV-1 non-B subtypes. Furthermore, polymorphisms such as protease L10I/V are ubiquitous in non-B subtypes, but their biological implications are still unknown. We evaluated resistance pathways emerging at treatment failure in a cohort of HIVinfected individuals in Mali, and characterized in vitro the role of L10I/V. Methods: Genotypic resistance testing was performed on plasma obtained from 132 HIV-infected individuals from Mali before and after 9 months of treatment using population sequencing. CRF02_AG chimeric viruses containing 10I/V mutants CRF02_AG were constructed using site directed mutagenesis and susceptibility to protease inhibitors (PI) as well as replicative capacity were determined in a PBMC culture assay. Results: At treatment initiation, 11/132 (8.3%; 95% CI 3.6-13.0%) patients harboured resistance mutations to NRTI (D67N, T69N, L210W, K219E and T215A) or NNRTI (K103N, V108I and V179E). Among these 11 patients, 5 with NNRTI mutations were in virological failure after 9 months of treatment. Six others with one Thymidine Analog Mutations (TAM) did not show complete resistance. Overall, 18/132 (14.0%; 95% CI 8.1-19.9%) patients failed at 9 months and resistance mutations to NRTI or NNRTI could be identified in 8 (6.10%; 95% CI 2.0-10.2%). NRTI mutation M184V was the most commonly observed, followed by NNRTI mutations Y181C and K103N. Polymorphisms in protease such as L10I/V were observed frequently. Their role was evaluated in vitro. CRF02_AG wt_10L showed a slight increase in IC50 for darunavir, lopinavir and nelfinavir compared to subtype B HXB2_10L with 1.2, 1.3 and 1.5 Fold-Changes (FC) respectively. Mutant's viruses CRF02_AG L10I and CRF02_AG L10V showed a slight increase in IC50 for indinavir with 1.30 and 1.20 FC and a slight decrease in IC50 for lopinavir with 0.78 FC and 0.75 FC respectively compared to CRF02_AG wt_10L. We did not observe any difference in replicative capacity between CRF02_AG wt_10L and HXB2. However, compared to CRF02_AG wt_10L , mutants, viruses CRF02_AG L10I, and CRF02_AG L10V showed a significant reduction in replication capacity by 10% (p<0.03) and 12% (p<0.02) respectively. Conclusion: Primary resistance to NRTI and NNRTI impacts response to treatment. The presence of a single TAM mutation may have limited impact on first line treatment in CRF02_AG. A common polymorphism in non-B subtypes, L10V, may affect susceptibility of certain PIs. In the context of large-scale use of antiretroviral, monitoring the emergence of resistance in non-B subtypes is important to preserve treatment options.
Journal of Virology, 1996
Indinavir (IDV) (also called CRIXIVAN, MK-639, or L-735,524) is a potent and selective inhibitor of the human immunodeficiency virus type 1 (HIV-1) protease. During early clinical trials, in which patients initiated therapy with suboptimal dosages of IDV, we monitored the emergence of viral resistance to the inhibitor by genotypic and phenotypic characterization of primary HIV-1 isolates. Development of resistance coincided with variable patterns of multiple substitutions among at least 11 protease amino acid residues. No single substitution was present in all resistant isolates, indicating that resistance evolves through multiple genetic pathways. Despite this complexity, all of 29 resistant isolates tested exhibited alteration of residues M-46 (to I or L) and/or V-82 (to A, F, or T), suggesting that screening of these residues may be useful in predicting the emergence of resistance. We also extended our previous finding that IDV-resistant viral variants exhibit various patterns of...
AIDS, 2005
Intensification therapy adding a boosted protease inhibitor (PI) to a failing regimen has the potential to worsen the resistance profile. Sixty-six patients included in four different boosted PI intensification studies were assessed and resistance mutations in the reverse transcriptase and protease genes were evaluated at baseline and 4 weeks after the initiation of the intensification strategy. Only one of the 66 patients developed changes in their pattern of mutations able to generate or increase resistance to new drugs.