Virologic Failure Of Antiretroviral Therapy Research Articles

Virological failure of antiretroviral therapy and associated social and clinical factors in children and adolescents living with HIV

According to the World Health Organization, sustained virological suppression of 90 % should be achieved among children and adolescents living with HIV / AIDS, which makes it important to assess the prevalence of virological failure of antiretroviral therapy. The aim of this study was to determine the prevalence of virological failure and the clinical factors associated with it, as well as therapeutic drug monitoring in groups divided by the viral load level among children and adolescents with HIV. Materials and Methods: A retrospective analysis of the medical records of 184 children and adolescents receiving antiretroviral therapy and registered at the Irkutsk Regional Center for the Prevention and Control of AIDS and Infectious Diseases, Irkutsk, was carried out. The study included 172 children aged 1-18 years with perinatal HIV infection. Patients were divided into groups depending on the level of viral load: group 1 – 21 patients with viral load > 1000 copies/ml of plasma, group 2 – 42 patients with viral load 50– 1000 copies/ml of plasma, group 3 – 109 patients with undetectable viral load (< 50 copies/ml). All patients underwent standard tests in accordance with clinical guidelines for the treatment of HIV infection in children, as well as therapeutic drug monitoring. Results. Against the background of ongoing antiretroviral therapy, a significant number of patients 21 / 172 (12,2 %) experienced virological failure. The proportion of children and adolescents with incomplete suppression of HIV replication is 42 / 172 (24,4 %). Statistically significant differences were obtained by changing the ART regimen (p = 0,031). In the first group, the proportion of patients who changed the therapy regimen is 7 / 21 (33,3 %), which is two times less than in the group with a zero viral load of 70 / 109 (64,2 %). There are differences in the proportion of children and adolescents with zero concentrations of ritonavir and lopinavir (p = 0,020 and p = 0,012) in the three compared groups. The distribution of patients with zero concentrations was as follows: for ritonavir in the first group 3 / 17 (17,6 %), in the second – 8/37 (21,6 %), in the third group – 4/80 (5 %); for lopinavir – 4/17 (23,5 %), 6/36 (16,7 %), 3/80 (3,8 %), respectively. Conclusion. This study demonstrates that the prevalence of virological failure among children and adolescents receiving ART remains high. To achieve sustained virological suppression in children and adolescents taking a protease inhibitor regimen, adherence to therapy must be increased. As one of the methods for assessing adherence, therapeutic drug monitoring can be used.

Virological failure among people living with HIV receiving second-line antiretroviral therapy in Pune, India

BackgroundThe number of people receiving second-line antiretroviral therapy (ART) has increased as global access to ART has expanded. Data on the burden and factors associated with second-line ART virologic failure (VF) from India remain limited.MethodsWe conducted cross-sectional viral load (VL) testing among adults (≥ 18 years) who were registered at a publicly funded ART center in western India between 2014 and 2015 and had received second-line ART for at least 6 months. Sociodemographic and clinical characteristics were abstracted from routinely collected programmatic data. Logistic regression evaluated factors associated with VF (defined as VL > 1000 copies/mL).ResultsAmong 400 participants, median age was 40 years (IQR 34–44), 71% (285/400) were male, and 15% (59/400) had VF. Relative to participants without VF, those with VF had lower median CD4 counts (230 vs 406 cells/mm3, p < 0.0001), lower weight at first-line failure (49 vs 52 kg, p = 0.003), were more likely to have an opportunistic infection (17% vs 3%, p < 0.0001) and less likely to have optimal ART adherence (71% vs 87%, p = 0.005). In multivariable analysis, VF was associated with opportunistic infection (aOR, 4.84; 95% CI, 1.77–13.24), lower CD4 count (aOR 4.15; 95% CI, 1.98–8.71) and lower weight at first-line failure (aOR, 2.67; 95% CI, 1.33–5.34).ConclusionsWe found second-line VF in about a sixth of participants in our setting, which was associated with nearly fivefold increased odds in the context of opportunistic infection. Weight could be a useful clinical indicator for second-line VF.

Genetic diversity of the human immunodeficiency virus (HIV-1) in the Kaliningrad region

As is currently known, the epidemic process in the Kaliningrad Region was mainly associated with the spread of the recombinant form of HIV-1 (CRF03_AB); however, regular HIV importations from other countries and continents has created favorable conditions for emergence and spread of various recombinant forms of the virus.The most complete information on the diversity of recombinant forms in the region is also necessary to understand the structure of drug resistance (DR). The aim of the study was to explore the HIV-1 genetic diversity in the Kaliningrad Region. We studied 162 blood plasma samples obtained from patients from the Kaliningrad Region, both with confirmed virological failure of antiretroviral therapy (ART) and with newly diagnosed HIV infection. For reverse transcription and amplification of HIV genome fragments, diagnostic «AmpliSense HIVResist-Seq». The various recombinants between subtypes A and B (74%) were predominant in study group: recombinant was between CRF03_AB and subtype A (33.95%) and CRF03_AB-like (13.58%) were the most common. Among the "pure" subtypes of the virus, subtype A6 (16.67%). The circulation of subtypes B (3.70%) and G (1.23%) was also noted.Ninety-six patients (59.26%) were identified with at least one mutation associated with antiretroviral (ARV) drug resistance. The observed diversity of subtypes and recombinant forms of the virus implies that the new recombinants are actively emerging in the studied region, both between existing recombinant forms and "pure" subtypes, as well as between "pure" subtypes.

Determination of HIV Tropism in Patients with Antiretroviral Therapy Failure in Arkhangelsk Region

The aim of the study was to determine the tropism of the human immunodeficiency virus in patients with virological failure of antiretroviral therapy (ART) from the Arkhangelsk Region based on the analysis of the env gene V3 loop nucleotide sequence.Materials and methods. We used blood plasma samples obtained from 76 HIV-infected persons from the Arkhangelsk Region with virological failure of antiretroviral therapy. The nucleotide sequences of the HIV env gene C2-V3-C3 region were studied by PCR followed by sequencing. The genotype of the studied strains was determined based on the analysis of their phylogenetic relations with reference sequences from the international GenBank database, as well as using specialized programs. To predict viral tropism, the Garrido rule and the online bioinformatic tool Geno2Pheno[coreceptor] were used. The Geno2Pheno[coreceptor] algorithm, determines the false positive rate (FPR) based on the analysis of the env gene V3 loop nucleotide sequence. Results and discussion. Significantly lower representation of R5X4/X4-tropic HIV variants in long-term infected persons with subsubtype A6 virus compared to subtype B virus has been shown. For all FPR cut-off algorithms, a significant correlation between subtype and HIV tropism was observed (p=0.0014 and p=0.013 for FPR 10 % and FPR 20 %, respectively). While among subtype B strains, at least 57 % were identified as R5X4/X4-tropic variants (for an FPR of 10 %), including two strains classified as X4-tropic; among HIV subsubtype A6 even at an FPR of 20 %, the frequency of R5X4/X4-tropic samples only slightly exceeded 22 %. It can be assumed that the dynamics of changes in HIV tropism depends on the virus subtype. Significant differences in the distribution of amino acid residues of the V3 region sequences in the examined group between R5-tropic and R5X4/X4-tropic strains of subsubtype A6 for positions 18 (χ2=7.616, p=0.0058), 21 (χ2=7.281, p=0.007), 24 (χ2=5.587, p=0.0181), and 34 (χ2=5.144, p=0.0233) have been demonstrated. Among the R5X4/X4-tropic strains of the A6 subsubtype, amino acid substitutions were registered at positions 6, 19, 21, 26, 29, 30, which were not found in the R5-tropic A6 strains. The high occurrence frequency of a number of mutations previously described as presumably associated with resistance to maraviroc and similar drugs may indicate a natural polymorphism characteristic of the A6 subsubtype, which does not correlate with resistance to CCR5 co-receptor antagonists.

Risk Factors of Drug Resistance and the Potential Risk of HIV-1 Transmission of Patients with ART Virological Failure: A Population-Based Study in Sichuan, China.

BackgroundSichuan Province, in the interior of Southwest China, is the most severe HIV-affected area in China. Few data are currently available for people living with HIV/AIDS (PLWH) with virological failure of antiretroviral therapy (ART). Estimating the HIV-1 drug-resistant spread influencing factors and transmission patterns of the HIV-1 epidemic of PLWH with ART virological failure are critical in Sichuan.MethodsWe evaluated the drug-resistant transmission patterns on 5790 PLWH in 2018 with identified pol sequences of the five main HIV-1 subtypes (ie, subtype B, CRF08_BC, CRF85_BC, CRF07_BC, and CRF01_AE) in Sichuan Province, China. The multivariate logistic regression model was used to explore potential influencing factors of the spread of drug resistance (DR) clustering in the genetic transmission network. Spatial analyses were applied to demonstrate drug-resistant spatial clustering patterns of spatial connections of HIV-1 intercity transmission. Genetic transmission networks were performed by comparing sequences, calculating the pairwise distance, and visualizing the network.ResultsThere were identified 452 transmission clusters containing 2159 of 5790 patients (37.29%) in the HIV-1 genetic transmission networks. Some clinical and demographic factors (eg, route of transmission, subtype) determined the DR clustering in the genetic transmission networks. The high drug-resistant clustering rates were mainly distributed in the Southern and Northeast of Sichuan Province (eg, Deyang, Neijiang), especially for CRF85_BC, which showed the highest clustering rate. Some cities had with strong intracity links (eg, Yibin, Neijiang), some cities had with strong transmission links with another city (eg, Ziyang and Guangyuan), 12 of 37 drug resistance mutation sites had a significant difference in the five subtypes (P < 0.001).ConclusionOur findings revealed the HIV-1 drug-resistant spread influencing factors and transmission patterns of PLWH with ART virological failure, which showed regions with high drug-resistant transmission of PLWH may not be a match for regions with severe epidemics in Sichuan, and it provided evidence-based to drug-resistant transmission targeting interventions.

HIV-1 genetic transmission networks among people living with HIV/AIDS in Sichuan, China: a genomic and spatial epidemiological analysis

SummaryBackgroundSpatialized HIV genetic transmission networks can help understand dynamic changes of HIV-1 at the regional level. This study aimed to combine genomic, epidemiological, and spatial data to investigate the patterns of the HIV-1 epidemic at both individual and regional levels among people living with HIV (PLWH) with virological failure of antiretroviral therapy (ART).MethodsWe evaluated the transmission patterns of 5,790 PLWH with identified pol sequences of the five main HIV-1 subtypes (B, CRF08_BC, CRF85_BC, CRF07_BC, and CRF01_AE) in Sichuan Province, China. A phylogenetic cluster was defined as a group of sequences with genetically similar HIV strains, with all phylogenetic clusters forming an HIV-1 genetic transmission network for each subtype. Logistic regression was used to identify the potential risk factors for phylogenetic clustering. Spatial analysis was applied to demonstrate the geographic patterns of phylogenetic clustering rates; intensity matrices and flow maps were made to demonstrate the intensity of transmission within and between cities.FindingsThere were 2,159 (37.3%) of 5,790 PLWH, distributed in 452 phylogenetic clusters. Some individual clinical and behavioral factors were associated with phylogenetic clustering, including a viral load of >50,000 copies/ml (OR=1.16, 95%CI=1.02-1.33), infection of other sexually transmitted diseases (OR=1.38, 95%CI=1.12-1.69), and ≥5 non-marital sexual partners (OR=1.25, 95%CI=1.03-1.51), while >3 years of treatment since the initial ART was associated with less likelihood of phylogenetic clustering (OR=0.82, 95%CI=0.70-0.97). The phylogenetic clustering rates varied regionally and were highest in the central region of Sichuan, especially for subtype CRF08_BC. The significant spatial clusters of high and low phylogenetic clustering rates were detected in the east (Dazhou for B; Zigong and Luzhou for CFR08_BC) and west (Yaan and Ganzi for CRF07_BC), respectively. The proportion of intercity transmission varied across cities from 0.14 (Yibin) and 1.00 (Ganzi). Stronger intercity transmission than average existed between some cities, e.g., between Deyang and Neijiang. CRF07_BC was the most widespread subtype between cities, and CRF85_BC (a novel HIV-1 subtype) showed strong intercity transmission (e.g., between Yibin and Guangan).InterpretationThe phylogenetic clustering rates and intercity connections of HIV-1 have varied geographically, possibly due to varying human mobility, traffic convenience, and economic activities. Our findings enhanced the understanding of the dynamics of HIV-1 transmission from individual to city level, and demonstrated a novel cross-disciplinary (epidemiological, genetic, and spatial) approach by which we identified high-risk populations and areas. Our approach could be adapted to other regions for precision public health interventions.FundingThe National Natural Science Foundation of China, Sichuan Science and Technology Program, Project of Sichuan Provincial Health Committee, Science and Technology Project of Sichuan Provincial Health Committee, Wuhan University 351 Talent Program, 2020, and the International Institute of Spatial Lifecourse Epidemiology (ISLE).

Polymorphisms at CYP enzymes, NR1I2 and NR1I3 in association with virologic response to antiretroviral therapy in Brazilian HIV-positive individuals.

Virologic failure of antiretroviral therapy (ART) may be explained by single nucleotide polymorphisms (SNPs) in drug absorption and metabolism genes. Here, we characterized the associations between polymorphisms in cytochrome P450 enzymes' genes CYP2B6 and CYP3A4/A5, nuclear receptor genes NR1I2/3, and initial ART efficacy among 203 HIV-positive individuals from Rio de Janeiro. Association between SNPs and virologic control was evaluated after 6 and 12 months of follow-up using Cox regression models. The SNP rs2307424 (NR1I3) was associated with increased virologic response after 12 months of treatment, while rs1523127 (NR1I2), rs3003596, and rs2502815 (NR1I3) were associated with decreased response. Increased virologic response after 12 months (adjHR = 1.54; p = 0.02) was also observed among carriers of the NR1I3 haplotype rs2502815G-rs3003596A-rs2307424A versus the reference haplotype G-A-G. Our results suggest that NR1I2 and NR1I3 variants are associated with virologic responses to ART among Brazilians.

Evaluation of the HIV-1 drug resistance to elsulfavirine and the effectiveness of it among Russian treatment-naïve patients

The aim of the study: to analyze the prevalence of resistance mutations to elsulfavirine and to evaluate the effectiveness of it among HIV-infected treatment-naïve patients in real clinical practice.Materials and methods. The study included 578 patients with HIV infection, which divided into 3 groups. The first group is 354 HIV-infected treatment-naïve patients for whom HIV-1 nucleotide sequences were obtained as part of routine drug resistance testing. The second study group included 111 HIV-infected treatment-naïve patients, tested for drug resistance before the antiretroviral therapy containing elsulfavirine. The third study group included 113 HIV-infected treatment-naïve patients, each of whom was assigned a treatment regimen containing elsulfavirine without prior drug resistance testing. The observation period for patients of the second and third groups who received treatment was 24 weeks. To assess the effectiveness of antiretroviral therapy in patients, viral load, CD4+ T-cell counts, and adherence to therapy were assessed. HIV-1 subtypes and drug resistance mutations were determined using the Stanford HIV Resistance Database (v. 8.9-1). To clarify the results of subtyping, phylogenetic analysis of nucleotide sequences was carried out using the MEGA program (v. 6.0).Results. The prevalence of mutations associated with decreased susceptibility to elsulfavirine among HIV-infected treatment-naïve patients was 1.7% and 4.5% for the first and second groups of patients, respectively. All of the patients have only single resistance mutations which, according to the results of preclinical studies, cannot cause drug resistance. The use of elsulfavirine in real clinical practice among treatment-naïve patients has demonstrated good virological and immunological efficacy of the drug. As a result of 24 weeks of therapy in patients of the second group, no treatment ineffectiveness, and the development of drug resistance were observed. Among the patients of the third group, 6 patients (5.3%) have the virological failure of therapy associated with the resistance to the used drugs. All patients with virological failure had a resistance mutation profile associated with a high level of drug resistance to one of the drugs in the treatment regimen, lamivudine. Additionally, 1 patient had a combination of mutations that reduce susceptibility to elsulfavirine, and 4 patients had mutations that can reduce susceptibility to elsulfavirine in combination with other mutations.Conclusion. The low prevalence of mutations associated with a decrease in susceptibility to elsulfavirine and the absence of combinations of mutations make it possible to predict the successful use of this drug for Russian treatment-naïve patients. Reported cases of virological failure of antiretroviral therapy are difficult to interpret in the context of elsulfavirine due to the lack of an exact list of mutations and their combinations, and associations with the degree of resistance to it. This study describes for the first time the mutation profiles in patients with virological failure of therapy containing elsulfavirine and demonstrates the necessity of the further study of drug resistance profile to drug in vitro and in vivo.

Urgent need to improve programmatic management of patients with HIV failing first-line antiretroviral therapy.

Delayed identification and response to virologic failure in case of first-line antiretroviral therapy (ART) in resource-limited settings is a threat to the health of HIV-infected patients. There is a need for the implementation of an effective, standardized response pathway in the public sector. We evaluated published cohorts describing virologic failure on first-line ART. We focused on gaps in the detection and management of treatment failure, and posited ways to close these gaps, keeping in mind scalability and standardization. Specific shortcomings repeatedly recorded included early loss to follow-up (>20%) after recognized first-line ART virologic failure; frequent delays in confirmatory viral load testing; and excessive time between the confirmation of first-line ART failure and initiation of second-line ART, which exceeded 1 year in some cases. Strategies emphasizing patient tracing, resistance testing, drug concentration monitoring, adherence interventions, and streamlined response pathways for those failing therapy are further discussed. Comprehensive, evidence-based, clinical operational plans must be devised based on findings from existing research and further tested through implementation science research. Until this standard of evidence is available and implemented, high rates of losses from delays in appropriate switch to second-line ART will remain unacceptably common and a threat to the success of global HIV treatment programs.

Genetic transmission networks of HIV-1 CRF07_BC strain among HIV-1 infections with virologic failure of ART in a minority area of China: a population-based study

BackgroundThe drug resistance and the virologic failure of antiretroviral therapy (ART) are quite severe in Liangshan. A better understanding of the virologic failure of ART and the HIV-1 transmission network dynamics is essential for the surveillance and prevention of HIV. Here, we analyzed the HIV-1 CRF07_BC strain genetic transmission networks and their associated factors among people living with HIV-1 (PLWH) who had virologic failure of ART by using close genetic links.MethodsThe drug-resistant mutations were determined using the Stanford University HIV Drug Resistance Database. HIV-1 pol genes sequences were used for phylogenetic and genotypic drug resistance analysis. The genetic transmission networks were performed by comparing sequences, constructing the phylogenetic tree, calculating the pairwise distance, and visualizing the network.ResultsA total of 1050 PLWH with CRF07_BC pol sequences were finally identified and included in the genetic transmission network analysis from 2016 to 2017. Of the 1050 CRF07_BC pol sequences, 346 (32.95%) fell into clusters at a genetic distance of 0.006, resulting in 137 clusters ranging in size from 2 to 40 individuals. Subjects who were widowed or divorced were less likely to form a genetic transmission network (adjusted OR: 0.50), while subjects who had shared a needle ≥ five times were more likely to form a network (adjusted OR: 1.88).ConclusionsThe genetic transmission networks revealed the complex transmission pattern, highlighting the urgent need for transmission monitoring of virologic failure of ART and selection of more effective therapeutic regimens to promote viral suppression.

Genotypic and pharmacoresistant HIV characteristics in patients in the Socialist Republic of Vietnam

To evaluate the molecular-epidemiological structure and pharmacoresistant HIV variants in HIV-infected individuals in Ho Chi Minh City (Socialist Republic of Vietnam), nucleotide sequences of the polymerase gene fragment (pol) HIV were analyzed in 42 patients (4 people with newly diagnosed HIV infection and 38 with virologic failure of antiretroviral therapy).Results. In the examined group, HIV circulating recombinant form CRF01_AE (92,2%) prevailed compared to genotype B (5,3%), CRF08_BC was detected in one patient (2,6%). Among people with newly diagnosed HIV infection, 75% were genotype CRF01_AE and 25% were genotype B. The drug resistance mutations to any drugs in 76,2% of patients were detected. Among isolates with identified pharmacoresistance, 43.75% had single mutations. Mutations to IR were more common (84,8%) than mutations to PI (15,2%). The most common mutations were NNRTIs — 47,8%, followed by NRTIs (37%) and PI (15,2%). Isolates with pharmacoresistance only to NRTIs amounted to 9,4% (7,1% of the general group), only to NNRTIs 28,1% (21,4% of the general group), only to PI 12,5% (9,5% from the general group), simultaneously to PI and NRTI 6,25% (4,8% of the general group), to PI and NNRTI 3,1% (2,4% of the general group), to NRTI and NNRTI 37,5% (28,6% of the general group), isolates with drugs resistance mutations to all three groups simultaneously were not detected. The drug resistance mutations occurrence and the occurring number naturally polymorphic variants in patients with two / three ARV regimens were significantly higher than those in patients with one regimen, regardless of the treatment duration. A pharmacoresistance mutation was detected in an ART-naive patient. Based on the foregoing, it seems necessary to monitor the HIV drug resistance in Vietnam to both those receiving ART and those who are ART-naive. K

HIV MOLECULAR EPIDEMIOLOGY AND PHARMACO-RESISTANCE IN PATIENTS WITH ANTIRETROVIRAL THERAPY FAILURE IN ARKHANGELSK DISTRICT

Introduction . The HIV epidemic remains the most devastating in the history of mankind, despite comprehensive preventive measures. The HIV pharmacological resistance to several groups drugs at once is particular importance since this significantly reduces the therapy possibilities. Due to the low adherence to the treatment of patients certain categories, as well as the HIV drug-resistant transmission under various conditions possibility, treatment may not give positive results in 16–27% of patients who did not receive ART and in 50–70% of previously treated patients. The aim of our work was to evaluate the molecular-epidemiological structure and pharmacoresistant HIV variants in patients with antiretroviral therapy virologic failure in Arkhangelsk. Materials and methods. To evaluate the molecular-epidemiological structure and pharmacoresistant HIV variants in 76 HIV-infected patients with virologic failure of antiretroviral therapy from the Arkhangelsk region, HIV polymerase gene ( pol ) nucleotide sequences were analyzed. Results. In the examined group, HIV subtype A6 (IDU-A) prevailed (89,5%) compared with subtype B (9,2%), in one case (1,3%) the variant CRF03_AB was detected. For 86,8% of patients, resistance to any drugs was determined. Including resistance to protease inhibitors mutations — 33,3%, to revertase inhibitors — 92,4%. Isolates with pharmacoresistance only to NRTIs amounted to 16,6%, to NNRTIs 1,5%, to PI 10,6%, simultaneously to PI and NRTIs 12,1%, to NRTIs and NNRTIs 46,96%, to all three groups of drugs at the same time — 12,1%. The most common mutations are drug resistance to lamivudine and emtricitabine (M184V), nevirapine and efavirenze (K103N, G190S), thymidine analogs (T215F/Y and/or K219Q/E and/or D67N), and non-thymidine L nucleoside analogues).

Identification and molecular-genetic characteristics of the hepatitis B virus among HIV-infected patients in Arkhangelsk.

To estimate the prevalence and characterize the hepatitis B virus among HIV-infected patients with virological failure of antiretroviral therapy in Arkhangelsk. HBV markers determinations (HBsAg, anti-HBs IgG, antiHBcor IgG, DNA HBV) were performed in isolates from blood plasma samples 64 HIV-infected patients with virological failure of antiretroviral therapy (viral load >50 IU / ml after 6 months of antiretroviral therapy or an increase in viral load after primary suppression of viral replication). For the detection of the hepatitis B virus, nucleic acids were isolated using the commercial kit «AmplePrime Ribo-prep». The virus presence analysis was performing by the polymerase chain reaction (PCR) method with hybridization-fluorescence detection in "real time" using the commercial set of «AmpliSens® HBV-FL». In the future, we used the method developed by the Saint-Petersburg Pasteur Institute, which allows detecting HBV in biological material with a low viral load. HBsAg-negative (occult) HBV was detect in 28 (43.8%) HIVinfected patients. Only HBV genotype D was detected, and the HBV subgenotype D1 prevailed (39.3%) compared with the HBV subgenotype D2 (32.1%) and D3 (28.6%). Serological markers in 42.8% of patients with HBV DNA were founding. Two HBV isolates with drug resistance mutations in the polymerase gene, leaded to amino acid substitutions (L180M, M204V) associated with the resistance development to lamivudine, entecavir, telbivudine and tenofovir were identifying. The occult (HBsAg-negative) HBV high prevalence among HIV-infected patients suggests the need to use molecular-biological diagnostic methods to identify HBV, as well as to analyze the HBV drug resistance mutation before starting antiretroviral therapy for HIV.

Tuberculosis incidence among people living with HIV/AIDS with virological failure of antiretroviral therapy in Salvador, Bahia, Brazil

Antiretroviral therapy for HIV has led to increased survival of HIV-infected patients. However, tuberculosis remains the leading opportunistic infection and cause of death among people living with HIV/AIDS. Tuberculosis has been shown to be a good predictor of virological failure in this group. This study aimed to evaluate the incidence of tuberculosis and its consequences among individuals diagnosed with virological failure of HIV. This was a retrospective cohort study involving people living with HIV/AIDS being followed-up in an AIDS reference center in Salvador, Bahia, Brazil. Individuals older than 18 years with HIV infection on antiretroviral therapy for at least six months, diagnosed with virological failure (HIV-RNA greater than or equal to 1000copies/mL), from January to December 2013 were included. Tuberculosis was diagnosed according to the criteria of the Brazilian Society of Pneumology. Fourteen out of 165 (8.5%) patients developed tuberculosis within two years of follow-up (incidence density=4.1 patient-years). Death was directly related to tuberculosis in 6/14 (42.9%). A high incidence and tuberculosis-related mortality was observed among patients with virological failure. Diagnosis of and prophylaxis for tuberculosis in high-incidence countries such as Brazil is critical to decrease morbidity and mortality in people living with HIV/AIDS.

The association between detected drug resistance mutations and CD4+ T-cell decline in HIV-positive individuals maintained on a failing treatment regimen.

To analyse the effect of drug resistance mutations (DRM) on CD4+ T-cell (CD4) trends in HIV-positive people maintained on virologically failing antiretroviral therapy (ART). Individuals from two large cohorts experiencing virological failure (VF) while maintained on ART with ≥1 CD4 count and ≥1 resistance test were included. CD4 slopes were estimated using linear mixed models. Principal component analysis (PCA) was used to assess the effect of clusters of mutations, defined using extracted component based scores from the PCA, on CD4 decline. 5,357 individuals contributing 7,661 VF episodes were included: any DRM were detected in 88.8% of episodes. After adjustment, CD4 counts declined less steeply during episodes where DRM were detected compared to episodes with no DRM (difference =28 cells/mm3/year, 95% CI =18, 39; P<0.001). Among individuals with at least one DRM, we found evidence that any nucleoside/nucleotide reverse transcriptase inhibitor (NRTI) resistance, the reverse transcriptase (RT) mutations M184V, D67N and T215Y as well as the protease mutations V82A and I54V were associated with reduced CD4 declines. The detection of any non-nucleoside reverse transcriptase inhibitor resistance, the RT mutations V179D and L74V were associated with steeper CD4 declines. The presence of some mutation patterns similar to the clusters identified by the PCA also affected the CD4 decline. Detection of resistance and of certain DRM during VF of ART has a small but significant favourable effect on CD4 decline.

Pooled Nucleic Acid Testing to Detect Antiretroviral Treatment Failure in HIV-Infected Patients in Mozambique.

In resource-limited settings, viral load monitoring of HIV-infected patients receiving antiretroviral therapy (ART) is not readily available because of high costs. Here, we compared the accuracy and costs of quantitative and qualitative pooled methods with standard viral load testing. Blood was collected prospectively from 461 patients receiving first-line ART in Mozambique who had not been evaluated previously with viral load testing. Screening for virologic failure of ART was performed quantitatively (ie, standard viral loads) and qualitatively [one and 2 rounds of polymerase chain reaction (PCR)]. Individual samples and minipools of 5 samples were then analyzed using both methods. The relative efficiency, accuracy, and costs of each method were calculated based on viral load thresholds for ART failure. Standard viral load testing of individual samples revealed a high rate of ART failure (19%-23%) across all virologic failure thresholds, and the majority of the patients (93%) with viral loads >1500 copies per milliliter had genotypic resistance to drugs in their ART regimen. Pooled quantitative screening and deconvolution testing had positive and negative predictive values exceeding 95% with cost savings of $11,250 compared with quantitative testing of each sample individually. Pooled qualitative screening and deconvolution testing had a higher cost savings of $30,147 for 1 PCR round and $25,535 for 2 PCR rounds compared with quantitative testing each sample individually. Both pooled qualitative PCR methods had positive and negative predictive values ≥90%, but the pooled 1-round PCR method had a sensitivity of 64%. Given the high rate of undiagnosed ART failure and drug resistance in this cohort, it is clear that virologic monitoring is urgently needed in this population. Here, we compared alternative methods of virologic monitoring with standard viral load testing of individual samples and found these methods to be cost saving and accurate. The test characteristics of each method will likely need to be considered for each local population before it is adopted.

Evaluation of Clinical and Immunological Markers for Predicting Virological Failure in a HIV/AIDS Treatment Cohort in Busia, Kenya

BackgroundIn resource-limited settings where viral load (VL) monitoring is scarce or unavailable, clinicians must use immunological and clinical criteria to define HIV virological treatment failure. This study examined the performance of World Health Organization (WHO) clinical and immunological failure criteria in predicting virological failure in HIV patients receiving antiretroviral therapy (ART).MethodsIn a HIV/AIDS program in Busia District Hospital, Kenya, a retrospective, cross-sectional cohort analysis was performed in April 2008 for all adult patients (>18 years old) on ART for ≥12 months, treatment-naive at ART start, attending the clinic at least once in last 6 months, and who had given informed consent. Treatment failure was assessed per WHO clinical (disease stage 3 or 4) and immunological (CD4 cell count) criteria, and compared with virological failure (VL >5,000 copies/mL).ResultsOf 926 patients, 123 (13.3%) had clinically defined treatment failure, 53 (5.7%) immunologically defined failure, and 55 (6.0%) virological failure. Sensitivity, specificity, positive predictive value, and negative predictive value of both clinical and immunological criteria (combined) in predicting virological failure were 36.4%, 83.5%, 12.3%, and 95.4%, respectively.ConclusionsIn this analysis, clinical and immunological criteria were found to perform relatively poorly in predicting virological failure of ART. VL monitoring and new algorithms for assessing clinical or immunological treatment failure, as well as improved adherence strategies, are required in ART programs in resource-limited settings.

A Combined Screening Platform for HIV Treatment Failure and Resistance

BackgroundTo develop a low cost method to screen for virologic failure of antiretroviral therapy (ART) and HIV-1 drug resistance, we performed a retrospective evaluation of a screening assay using serial dilutions of HIV-1 RNA-spiked blood plasma and samples from patients receiving >6 months of first-line ART.MethodsSerial dilution testing was used to assess sensitivity of a simple PCR-based assay (targeted at ≥1,000 HIV RNA copies/mL). We created blood plasma minipools of five samples, extracted HIV RNA from the pools, PCR amplified the reverse transcriptase (RT) coding region of the HIV-1 pol gene from extracted RNA, sequenced PCR product of positive pools, and used sequences to determine drug resistance. Sensitivity, specificity, and predictive values were determined for different levels of virologic failure based on maximum viral loads of individual samples within a pool.ResultsOf 295 samples analyzed, 43 (15%) had virologic failure at ≥50 copies/mL (range 50–10,500 copies/mL, four at ≥1,000 copies/mL). The assay demonstrated 100% sensitivity to detect virus from these four samples, requiring only one round of PCR, and 56% and 89% sensitivity to detect samples with ≥50 and ≥500 copies/mL using two rounds. Amplified PCR products of all positive pools were successfully sequenced and 30% harbored ≥1 major resistance mutation. This method would have cost 10% of the combined costs of individual viral load and resistance testing.ConclusionsWe present a novel method that can screen for both virologic failure of first-line ART and drug resistance. The method is much less expensive than current methods, which may offer sustainability in resource-limited settings.

Accuracy of WHO CD4 cell count criteria for virological failure of antiretroviral therapy

To examine the accuracy of the World Health Organization immunological criteria for virological failure of antiretroviral treatment. Analysis of 10 treatment programmes in Africa and South America that monitor both CD4 cell counts and HIV-1 viral load. Adult patients with at least two CD4 counts and viral load measurements between month 6 and 18 after starting a non-nucleoside reverse transcriptase inhibitor-based regimen were included. WHO immunological criteria include CD4 counts persistently <100 cells/microl, a fall below the baseline CD4 count, or a fall of >50% from the peak value. Virological failure was defined as two measurements > or =10 0000 copies/ml (higher threshold) or > or =500 copies/ml (lower threshold). Measures of accuracy with exact binomial 95% confidence intervals (CI) were calculated. A total of 2009 patients were included. During 1856 person-years of follow up 63 patients met the immunological criteria and 35 patients (higher threshold) and 95 patients (lower threshold) met the virological criteria. Sensitivity [95% confidence interval (CI)] was 17.1% (6.6-33.6%) for the higher and 12.6% (6.7-21.0%) for the lower threshold. Corresponding results for specificity were 97.1% (96.3-97.8%) and 97.3% (96.5-98.0%), for positive predictive value 9.5% (3.6-19.6%) and 19.0% (10.2-30.9%) and for negative predictive value 98.5% (97.9-99.0%) and 95.7% (94.7-96.6%). The positive predictive value of the WHO immunological criteria for virological failure of antiretroviral treatment in resource-limited settings is poor, but the negative predictive value is high. Immunological criteria are more appropriate for ruling out than for ruling in virological failure in resource-limited settings.

Minority Quasispecies of Drug‐Resistant HIV‐1 That Lead to Early Therapy Failure in Treatment‐Naive and ‐Adherent Patients

Early virological failure of antiretroviral therapy associated with the selection of drug-resistant human immunodeficiency virus type 1 in treatment-naive patients is very critical, because virological failure significantly increases the risk of subsequent failures. Therefore, we evaluated the possible role of minority quasispecies of drug-resistant human immunodeficiency virus type 1, which are undetectable at baseline by population sequencing, with regard to early virological failure. We studied 4 patients who experienced early virological failure of a first-line regimen of lamivudine, tenofovir, and either efavirenz or nevirapine and 18 control patients undergoing similar treatment without virological failure. The key mutations K65R, K103N, Y181C, M184V, and M184I in the reverse transcriptase were quantified by allele-specific real-time polymerase chain reaction performed on plasma samples before and during early virological treatment failure. Before treatment, none of the viruses showed any evidence of drug resistance in the standard genotype analysis. Minority quasispecies with either the M184V mutation or the M184I mutation were detected in 3 of 18 control patients. In contrast, all 4 patients whose treatment was failing had harbored drug-resistant viruses at low frequencies before treatment, with a frequency range of 0.07%-2.0%. A range of 1-4 mutations was detected in viruses from each patient. Most of the minority quasispecies were rapidly selected and represented the major virus population within weeks after the patients started antiretroviral therapy. All 4 patients showed good adherence to treatment. Nonnucleoside reverse-transcriptase inhibitor plasma concentrations were in normal ranges for all 4 patients at 2 separate assessment times. Minority quasispecies of drug-resistant viruses, detected at baseline, can rapidly outgrow and become the major virus population and subsequently lead to early therapy failure in treatment-naive patients who receive antiretroviral therapy regimens with a low genetic resistance barrier.