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In the phase 3 BRIGHTE study in heavily treatment-experienced adults with multidrug-resistant HIV-1, fostemsavir plus optimized background therapy (OBT) resulted in sustained rates of virologic suppression through 96 weeks. HIV-1 RNA <40 copies/mL was achieved in 163/272 (60%) Randomized Cohort (RC) participants (with 1 or 2 remaining approved fully active antiretrovirals) and 37/99 (37%) Non-randomized Cohort (NRC) participants (with 0 fully active antiretrovirals). Here we report genotypic and phenotypic analyses of HIV-1 samples from 63/272 (23%) RC participants and 49/99 (49%) NRC participants who met protocol-defined virologic failure (PDVF) criteria through Week 96. The incidence of PDVF was as expected in this difficult-to-treat patient population and, among RC participants, was comparable regardless of the presence of predefined gp120 amino acid substitutions that potentially influence phenotypic susceptibility to temsavir (S375H/I/M/N/T, M426L, M434I, M475I) or baseline temsavir 50% inhibitory concentration fold change (IC 50 FC). The incidence of PDVF was lower among participants with higher overall susceptibility score to newly used antiretrovirals (OSS-new), indicating that OSS-new may be a preferred predictor of virologic outcome in heavily treatment-experienced individuals. Predefined gp120 substitutions, most commonly M426L or S375N, were emergent on treatment in 24/50 (48%) RC and 33/44 (75%) NRC participants with PDVF, with related increases in temsavir IC 50 FC. In BRIGHTE, PDVF was not consistently associated with treatment-emergent genotypic or phenotypic changes in susceptibility to temsavir or to antiretrovirals in the initial OBT. Further research will be needed to identify which factors are most likely to contribute to virologic failure in this heavily treatment-experienced population (ClinicalTrials.gov, NCT02362503).

Objectives: This study analyzed Protease-PR and Reverse Transcriptase-RT HIV-1 genomic information entropy metrics among patients under antiretroviral virologic failure, according to the numbers of virologic failures or resistance mutations., Methods: For this purpose, we used genomic sequences from PR and RT of HIV-1 from a cohort of chronic patients followed up at São Paulo Hospital., Results: Informational entropy proportionally increases with the number of antiretroviral virologic failures in PR and RT (p < .001). Affected regions of PR were related to catalytic and structural functions, such as Fulcrum (K20) Flap (M46) and Cantilever (A71). In RT, this occurred at Fingers (E44) and Palm (K219). Informational entropy increases according to the number of resistance mutations in PR and RT (p < .001). Higher PR entropy was proportional to the resistance mutation numbers in Fulcrum (L10), Active site (L24) Flap (M46), Cantilever (L63) and near Interface (L90). In RT, they related to regions responsible for protein stability such as Fingers (T39) and Palm (L100)., Conclusions: The antiretroviral selective pressure affects HIV genomic informational entropy at the PR and RT regions, leading to the emergence of more unstable virions. Mapping the three-dimensional structure in these HIV-1 proteins is relevant to designing new antiretroviral targeting resistant strains., Competing Interests: Declaration of Competing Interest The authors have no declarations or conflicts of interest associated with this work., (Copyright © 2019 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: We investigated immune activation, exhaustion markers and cytokine expression upon stimulation in adolescents with vertical HIV infection., Methods: Thirty adolescents receiving antiretroviral therapy (ART) for vertical HIV infection, including 12 with detectable viral load (HIV/DET), 18 with undetectable viral load (HIV/UND) and 30 control adolescents without HIV infection (CONTROL), were evaluated for immune activation and programmed cell death protein-1 expression by flow cytometry, and 21 cytokines by Luminex Multiple Analyte Profiling technology after in vitro peripheral blood phytohemagglutinin stimulation., Results: Lower CD4 T cells and higher T cell activation and exhaustion markers were noted on CD4 T and on CD8 T cells and memory subsets from HIV/DET group, who also produced lower in vitro IFN-gamma, IL-10, IL-13, IL-17A, IL-5 and IL-6 than HIV/UND group. HIV/UND were comparable with CONTROL group in respect to CD4 T cell counts and T cell activation and exhaustion markers, but with higher in vitro production of ITAC (a chemokine with leukocyte recruitment function), IL-4 and IL-23. An inverse correlation between cytokine production and programmed cell death protein-1 expression on CD4 T and CD8 T subsets was detected., Conclusions: Persistent viremia despite ART leads to T cell activation and immune exhaustion with low cytokine production, whereas viral suppression by ART leads to parameters similar to CONTROL, although a different cytokine profile is observed, indicating residual HIV impact despite absence of detectable viremia.

Hypermutation alludes to an excessive number of specific guanine-to-adenine (G- >A) substitutions in proviral DNA and this phenomenon is attributed to the catalytic activity of cellular APOBECs. Population studies relating hypermutation and the progression of infection by human immunodeficiency virus type 1 (HIV-1) have been performed to elucidate the effect of hypermutation on the natural course of HIV-1 infection. However, the many different approaches employed to assess hypermutation in nucleotide sequences render the comparison of results difficult. This study selected 157 treatment-naive patients and sought to correlate the hypermutation level of the proviral sequences in clinical samples with demographic variables, HIV-1 RNA viral load, and the level of CD4(+) T cells. Nested touchdown polymerase chain reaction (PCR) was performed with specific primers to detect hypermutation in the region of HIV-1 integrase, and the amplified sequences were run in agarose gels with HA-Yellow. The analysis of gel migration patterns using the k-means clustering method was validated by its agreement with the results obtained with the software Hypermut. Hypermutation was found in 31.2% of the investigated samples, and a correlation was observed between higher hypermutation levels and higher viral load levels. These findings suggest a high frequency of hypermutation detection in a Brazilian cohort, which can reflect a particular characteristic of this population, but also can result from the method approach by aiming at hypermutation-sensitive sites. Furthermore, we found that hypermutation events are pervasive during HIV-1 infection as a consequence of high viral replication, reflecting its role during disease progression.

To evaluate antiretroviral phenotypic susceptibility of wild-type HIV-1 strains circulating in Brazil, samples from antiretroviral-naive individuals infected with subtypes C (n=16), F (n=9), or B/F (n=7), where reverse transcriptase is B and protease is F, were phenotyped using the Antivirogram Assay (Virco, Mechelen, Belgium). Reduced susceptibility to protease inhibitors (PIs) was observed in one C and three F isolates. None of these samples had any known PI resistance mutations. The phenotypic fold change to one PI was above the biological cut-off in three of 96 (3.1%) clade F phenotypic determinations and in one of 96 (1.0%) clade C. Phenotypic resistance to at least one nucleoside reverse transcriptase inhibitor (NRTI) was found for two B/F, four C, and three F isolates. The phenotypic fold change in susceptibility to NRTIs was above the cut-off value in nine of 111 (8.1%) clade C determinations, as compared to three of 63 (4.8%) for clade F and two of 49 (4.1%) for clade B. The phenotypic fold change to non-NRTI (NNRTI) was above the cut-off in seven of 32 (21.9%) of C isolates determinations, whereas none of the F isolates had a decrease of susceptibility. Only two of the 16 C samples had a known NNRTI resistance mutation. The NNRTI fold change was above the cut-off value in three of 14 (21.4%) phenotypic determinations of Brazilian B/F recombinants, representing clade B reverse transcriptase. NNRTI susceptibility should be better investigated in clade C and B/F recombinants.

Treatment of HIV-1 infection with highly active antiretroviral therapy has led to sustained viral suppression in the plasma in a large number of children. However, studies have suggested that the integrated provirus in resting CD4+ T lymphocytes could be a source of reactivatable virus and maintain drug-resistant virus. We evaluated the resistance-related mutations in children receiving antiretroviral therapy with prolonged viral suppression. Thirty-two peripheral blood mononuclear cell samples from 16 children with viral loads that had been below detection limits for at least 12 months were obtained at two different time points and the DNAs sequenced. The median CD4 cell count was 1,016 cells/mm³ (347-2,588) and 938 cells/mm³ (440-3,038) at the first and second time points, respectively. The median follow-up time was 15 months (9-27). Six (37.5%) and seven (43.75%) of the 16 patients showed at least one NRTI-associated mutation in the first and second samples, respectively. Two out of 16 (12.5%) had an NNRTI-associated mutation at the first time point and three out of 16 (18.75%) at the second. In addition, 14 out of 16 (87.5%) had at least one PI-associated mutation at both time points. Despite plasma HIV-1 RNA suppression for at least 12 months, resistance-related mutations from previous antiretroviral failures could still be detected in archival virus. Furthermore, viral evolution occurred at the reverse transcriptase region in spite of viral suppression to levels below 400 copies/mL. Persistence of archival resistant virus may be relevant when considering future treatment options.

Objective: To investigates how the use of HIV-1 resistance tests influences physician decision-making., Methods: Ten experienced reference physicians from the Brazilian Network for Drug Resistance each received ten patients' case histories. The selected patients had experienced at least two virological failures. First, reference physicians were asked to empirically select a new regimen for each patient. Second, after genotype report (ViroSeq 2.6) was provided, and physicians were again asked to select a new regimen considering this additional information. Finally, they were asked to select a regimen after receiving a virtual phenotype result (vircoTYPE 3.9.00)., Results: In 79% of the cases, physicians changed their empirical choice of regimen after receiving the genotype report, resulting in an increase in the mean number of active drugs from 1.8 to 2.2 (p = 0.0003), while the average number of drugs/regimen remained at 4.0. After receipt of the virtual phenotype report, additional changes were made in 75% of the patient cases, resulting in an increase in the number of active drugs to 2.8 (p < 0.0001), while the average number of drugs/regimen remained at 4.0. After receipt of the genotype report, 48% of the changes were in NRTIs, 29% were in NNRTIs and 60% were in PIs; after consideration of the virtual phenotype, 61%, 10% and 49% of the changes, respectively, were in these categories of drugs. Fourteen percent of the physicians rated the genotype report as "extremely useful", whereas 34% rated the subsequent virtual phenotype report as "extremely useful" (p = 0.0003)., Conclusions: Resistance testing has a significant impact on physicians' choices of antiretroviral salvage therapies, and it promotes the selection of more active drugs.

Background: Agents that block the CCR5 coreceptor for human immunodeficiency virus (HIV) have demonstrated potent antiretroviral activity. In early clinical studies, the CCR5 antagonist vicriviroc proved to be a safe and effective component of combination antiretroviral therapy., Methods: This double-blind, dose-ranging, phase 2 trial randomized subjects to receive 30 mg or 20 mg of vicriviroc or placebo once daily plus re-optimized background therapy containing a protease inhibitor with ritonavir. Subjects were adults infected with CCR5-tropic HIV who were experiencing failure of triple antiretroviral regimens. The primary end point was mean change in baseline log(10) HIV RNA level at 48 weeks, based on an intent-to-treat analysis., Results: One hundred fourteen persons received vicriviroc at 30 mg (n = 39), vicriviroc at 20 mg (n =40), or placebo (n = 35). The mean change in baseline HIV RNA level at week 48 was -1.77 log(10) copies/mL for 30 mg of vicriviroc and -1.75 log(10) copies/mL for 20 mg of vicriviroc, compared with -0.79 log(10) copies/mL for placebo (P =.002 and P=.003, respectively, compared with placebo). Mean CD4 counts increased by 102, 136, and 63 cells/mm(3) for 30 mg vicriviroc, 20 mg vicriviroc, and placebo, respectively (P = .260 and P = .039, respectively, compared with placebo). Rates of adverse events (mostly mild-to-moderate) were 111.4, 112.5, and 147.4 events per 100 subject-years, respectively., Conclusions: Vicriviroc administered with a protease inhibitor plus ritonavir-containing regimen shows potent antiretroviral and immunologic activity sustained over 48 weeks in treatment-experienced patients., Clinical Trials Registration: NCT00243230 .

We characterized the virologic failure after an initially successful 48-week course of antiretroviral therapy among HIV/AIDS patients in a retrospective cohort study involving patients from Santos, Brazil. Patients with plasma HIV RNA below 500 copies/mL for 48 weeks were included. Variables analyzed included gender, age, level of education, marital status, mode of HIV acquisition, viral load, and CD4 cell count upon admission. There were 4,909 patients registered with the clinic, of which 669 patients met all the inclusion criteria (41.6% female and 58.4% male). Only 27.5% of the patients maintained undetectable viral loads during up to one year of follow-up. After 48 weeks, virologic failure occurred earlier in females and in patients first treated with an antiretroviral regimen other than highly active antiretroviral therapy. Patients who were married or had a steady partner experienced virologic failure later than did those who were separated or widowed. The percentage of public health clinic patients who maintain undetectable viral loads for a period of over a year is much lower than that observed among patients enrolled in clinical trials. Females, individuals in unstable relationships, single individuals and widowed individuals should be given special attention in order to improve durability of viral suppression.

Viral suppression after antiretroviral therapy is monitored by determining plasma HIV-1 through viral load assays. However, such assays only provide HIV-1 replication rates at the moment samples are drawn and do not reflect any trend in viremia fluctuation preceding sample collection. The objective of this study was to correlate the optical density (OD) of the less sensitive HIV-1 enzyme immunoassay (EIA), used in the serologic testing algorithm for recent HIV seroconversion, with viral loads in a group of HIV-infected patients on antiretroviral therapy. We studied samples from 20 previously antiretroviral-naive subjects treated with the zidovudine-lamivudine combination plus indinavir for a 20-week period. Viral loads were assessed using the less sensitive HIV-1 EIA at baseline and at 4-week intervals. There was a strong correlation between lower OD and viral load after introduction of antiretroviral drugs (p < 0.01). The ODs tended to decrease in parallel with drops in viral loads and remain steady when viral loads did not change significantly. These results suggest that the less sensitive HIV-1 EIA may be used as a complementary method for monitoring the efficacy of antiretroviral therapy, with special appeal in resource-poor areas where health professionals have limited laboratory expertise.

This study characterized HIV-1 among antiretroviral-naïve populations presenting recent infection (RI) or long-standing infection (LSI). Sera collected from January 1999 to December 2001 at an anonymous HIV testing site in Santos, Brazil, were submitted to serologic testing algorithm for recent HIV seroconversion (STARHS). The STARHS methodology uses a combination of a sensitive and a less sensitive version of an anti-HIV enzyme immunoassay (EIA), and specimens found to be positive on the sensitive EIA and negative on the less sensitive EIA are considered to represent RI. HIV-1 V3 and pol regions of those with RI and LSI were compared. Antiretroviral resistance was defined solely by genotypic analysis. Ninety samples were evaluated representing those taken from an original cohort of 345 individuals, for whom adequate samples were available. Of 90 HIV-positive individuals, 25 presented RI. Cumulatively, 36.8% of those with RI and 25% of those with LSI presented resistance to at least one antiretroviral class. In the pol and V3 regions, 47% and 53% of those with RI presented clade B viruses and B/F recombinant viruses, respectively, whereas 56.2%, 41.7%, and 2.1% of those with LSI harbored clades B, B/F, and clade C viruses, respectively. Primary resistance and the prevalence of B/F recombinants was high in this population. Monitoring HIV-1 genetic diversity is important for developing vaccines and treatment strategies.

We analyzed gp120V3 HIV-1 env region genetic diversity of 27 patients failing antiretrovirals and subjected to 12-week structured treatment interruption (STI). Based on heteroduplex mobility assays, eight patients presented low pre- and post-STI genetic diversity (G1); five presented high pre-STI but low post-STI diversity (G2); five presented low pre-STI and high post-STI diversity (G3); and nine, high pre- and post-STI diversity (G4). One patient from G1, two from G2 and two from G3 were subjected to proviral DNA end-point PCR and sequencing. In three patients, the dramatic disturbance caused by STI resulted in ancestral viral progeny activation, which repopulated the cell reservoir. In two patients presenting highly homogeneous sequences and low immune selective pressure (dN/dS ratio <1), this phenomenon was not observed. The mechanisms involved in viral evolution, in which antiretroviral therapy also applies selective pressure, sometimes affects coreceptor usage of circulating viruses, leading to the suppression of x4 strains.