Non-nucleoside Analogue Reverse Transcriptase Inhibitor Research Articles

Prevalence of people living with multidrug-resistant HIV and limited treatment options in Spain.

Our aim was to determine the prevalence and characteristics of people with HIV on antiretroviral therapy (ART) with multidrug resistance (MDR; confirmed resistance to three or more [or resistance to two or more plus contraindication to one or more] core ART classes) and limited treatment options (LTOs) in Spain. This was an observational, retrospective, multicentre, cross-sectional chart review study undertaken in five reference Spanish centres. Participants were people with HIV on ART with MDR and LTOs (detectable viral load [HIV-RNA >200 copies/mL], treatment-limiting drug-drug interaction [DDI], or intolerance precluding the use of one or more ART classes). Prevalence, demographic/clinical characteristics, and treatment options were assessed. Logistic regression analyses were used to identify MDR-associated variables. Of 14 955 screened people with HIV, 69 (0.46%) presented with MDR and 23 (0.15%) had LTOs. The population analysed was 73.9% male with a median age of 54.0 years; the median time since HIV diagnosis was 26.5 years, and median CD4+ cell count was 511.0 cells/μL. The only factor significantly associated with MDR (univariate analysis) was CD4+ cell count. Injection drug use was the most common transmission route. Comorbidities (mainly endocrine and cardiovascular disorders; 34.8% affecting HIV management) and concomitant treatments were frequent. No recent opportunistic infections were reported. Patients had been exposed to the following ART: nucleoside analogue reverse transcriptase inhibitors (100%), protease inhibitors (95.6%), non-nucleoside analogue reverse transcriptase inhibitors (87.0%), and integrase strand transfer inhibitors (82.6%). The available fully active drugs were dolutegravir (39.1%), bictegravir (30.4%), and raltegravir (21.7%). The prevalence of people with HIV with MDR and LTOs in Spain is very low, with approximately half of those studied not exhibiting virological suppression. Low CD4+ cell counts were associated with MDR. These findings may help address the impact and treatment needs of these patients and prevent clinical progression and transmission of MDR HIV.

A Phase-IV Non-interventional Study to Assess Virological Effectiveness, Safety, and Tolerability of DTG-based Antiretroviral Therapy in HIV-1 Infected Indian Persons Living with HIV.

Dolutegravir (DTG) is a novel yet preferential first-and-second-line treatment for persons living with HIV (PLH). Owing to its recent introduction, DTG-based regimens have not undergone a comprehensive, systematic evaluation regarding their real-world utilization and safety profile among a sizeable Indian population. This study aimed to assess the 24-week immunovirological outcomes, anthropometric and metabolic changes, tolerability, and adverse events (AEs) of DTG-based antiretroviral (ART) regimens. A single-centre phase-IV non-interventional observational study involving 322 ART-- naïve and treatment-experienced PLH initiating DTG-based-regimens until October 2022 were followed up for outcomes at 24 weeks. At 24 weeks, all PLH (n=113) in the naïve group, all PLH (n=67) in the first-line substitution group, 93.9% PLH (n=46) in the first-line failure group, and 95.7% PLH (n=89) in the second- line substitution group were virologically suppressed to plasma HIV-RNA <1000 copies/mL. Virological suppression rates to plasma HIV-RNA <200 copies/mL and <50 copies/mL were consistent among PLH who received DTG as first- or second-line ART. The mean-unadjusted weight gain observed was 3.5 kg (SE: 0.330), and it was significantly higher in PLH with poorer health at baseline (either HIV-RNA ≥ 1000 copies/ml or CD4 cell count <350 cells/μL). Overall, 27.3% PLH (n=88) gained ≥10% of their baseline body weight, corresponding to 3.7% incidence (n=10) of treatment-emergent clinical obesity [1]. DTG had an overall lipid-neutral effect, with an advantageous effect being observed in PLH switching from non-nucleoside analogue reverse-transcriptase inhibitors (NNRTI) or ritonavir-boosted protease inhibitors (b/PI), especially in dyslipidemic pre-treated PLH (median change in total cholesterol: 28.5 mg/dL and triglycerides: 51 mg/dL), possibly emanating from the withdrawal of the offending ART. The incidence of DTG-specific AEs, including CNS AEs, was low. Two PLH developed proximal myopathy and one developed transaminitis, warranting DTG discontinuation. Asymptomatic serum-CPK elevation and drug-induced transaminitis were seen in 25.2% (n=27) and 3.2% (n=10) PLH, respectively. No apparent negative effects on renal function were detected. Our results from a large Indian cohort indicate a favourable virological and metabolic response, with good tolerance of DTG-based ART at 24 weeks.

Anti-HIV Transcriptase Herbs: A Review

To date, combination antiretroviral (ARV) medication is considered the most effective treatment for people infected with the Human Immunodeficiency Virus (HIV). The primary purpose of ARV administration is to reduce the viral load, thereby enhancing HIV patients' immunological condition and minimizing mortality from opportunistic infections. Nowadays, a combination of NRTI (nucleoside analog reverse transcriptase inhibitor) and NNRTI (non-nucleoside analog reverse transcriptase inhibitor) is accepted therapy for HIV patients. Both have a mechanism for inhibiting the reverse transcriptase (RT) enzyme during viral replication. Reverse transcriptase (RT) is an enzyme that plays a role in the reverse transcription stage of the virus reproduction process. HIV RT converts proviral RNA into DNA, and the copy infects the host or target cell. The use of RT inhibitors for HIV-infected patients is becoming more common. Many investigations were conducted on plants that have the potential to operate as anti-HIV RT. In this review, we go over some of the potential herbs that serve as RT inhibitors. In this literature review, a search was carried out with the help of several search engines that matched the criteria, namely reverse transcriptase herbal inhibitors for HIV. The author came to the conclusion that there were 18 plants with relatively high activity as anti-HIV medicines with varied traits and working mechanisms from 162 papers gathered based on keywords. Furthermore, the findings of this study will serve as the foundation for the development of anti-HIV herbs as well as a source of antiretroviral therapy ingredients in the future.

Prevalence of Drug Resistance and Genetic Transmission Networks Among Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome Patients with Antiretroviral Therapy Failure in Guangxi, China.

Prevalence of drug resistance (DR) challenges the epidemic control of human immunodeficiency virus (HIV)-1. However, little is known about DR among patients with antiretroviral therapy (ART) failure in Guangxi province, China. This cross-sectional study was aimed to investigate the prevalence of DR and the characteristics of DR sequences in the genetic transmission network among HIV-1 patients with ART failure in Guangxi. We enrolled 358 eligible patients between 2012 and 2018. Blood samples were subjected to reverse transcription polymerase chain reaction, followed by sequencing of the HIV-1 polymerase (pol) gene. An online subtyping tool and neighbor-joining phylogenetic tree were used to determine the genotype. HIV-TRACE tool was used to constructed transmission network with a pairwise genetic distance of 0.013. DR was analyzed using the Stanford University HIV Drug Resistance Database. We obtained 293 pol-sequences from participants; CRF01_AE (75.4%), CRF 08_BC (15.7%), and CRF07_BC (8.5%) were the main subtypes, and an A1 subtype was detected in Guangxi for the first time. The overall prevalence of DR was 32.4% (95/293). Among those with identified DR, 25.6% were against non-nucleoside analog reverse-transcriptase inhibitors (NNRTIs), 17.7% were against nucleoside analog reverse-transcriptase inhibitors (NRTIs), and 14.3% were against both NRTIs and NNRTIs. The common drug-resistant mutations were M184V (10.2%), K103N (10.6%) and V179D (6.1%). The patients located in the southern Guangxi [adjust odds ratio (AOR) = 10.87], or whose blood plasma were taken in 2017-2018 (AOR = 3.98) had an increased risk of DR. Of the CRF01_AE, CRF07_BC, and CRF08_BC sequences, 18.6%, 8.0%, and 13.0% fell into clusters, respectively. Nine (9.7%) sequences from patients with DR fell into three clusters. The largest cluster containing 11 individuals was the CRF01_AE subtype, 27.3% of whom were DR patients. Although the prevalence of DR among ART failure patients in Guangxi was at a low level, the continuous surveillance of DR in ART patients is necessary.

High prevalence of pre-treatment HIV drug resistance in Papua New Guinea: findings from the first nationally representative pre-treatment HIV drug resistance study

Background Determining the prevalence of pre-treatment HIV drug resistance (PDR) is important to assess the effectiveness of first-line therapies. To determine PDR prevalence in Papua New Guinea (PNG), we conducted a nationally representative survey.MethodsWe used a two-stage cluster sampling method to recruit HIV treatment initiators with and without prior exposure to antiretroviral therapies (ART) in selected clinics. Dried blood spots were collected and tested for PDR.ResultsA total of 315 sequences were available for analysis. The overall PDR prevalence rate was 18.4% (95% CI 13.8–24.3%). The prevalence of PDR to non-nucleoside analog reverse-transcriptase inhibitors (NNRTIs) was 17.8% (95% CI 13.6–23.0%) and of PDR to nucleoside reverse transcriptase inhibitors (NRTIs) was 6.3% (95% CI 1.6–17.1%). The PDR prevalence rate among people reinitiating ART was 42.4% (95% CI 29.1–56.4%).ConclusionsPNG has a high PDR prevalence rate, especially to NNRTI-based first-line therapies. Our findings suggest that removing NNRTIs as part of first-line treatment is warranted and will lead to improving viral suppression rates in PNG.

Patterns of acquired HIV-1 drug resistance mutations and predictors of virological failure in Moshi, Northern Tanzania.

Emergence of HIV drug resistance poses a serious risk of inactivity to all currently approved antiretroviral drugs. Profiles of HIV drug resistance mutations (HIVDRM) and virological failure (VF) are not extensively studied in Tanzania. This study aimed to determine HIVDRM and predictors of VF in HIV-infected individuals failing first-line HIV drugs in Moshi, Northern Tanzania. A case-control study was conducted at Kilimanjaro Christian Medical Centre, Mawenzi, Pasua and Majengo health facilities with HIV-care and treatment clinics from October, 2017 to August, 2018. Cases and controls were HIV-infected individuals with VF and viral suppression (VS) respectively. HIV-1 reverse transcriptase and protease genes were amplified and sequenced. Stanford University’s HIV drug resistance database and REGA subtyping tool 3.0 determined HIVDRM and HIV-1 subtypes respectively. Odds ratios (OR) with 95% confidence interval (95% CI) investigated predictors of VF. P-value < 5% was considered statistically significant. A total of 124 participants were recruited, of whom 63 (50.8%) had VF, 61 (49.2%) had VS and 82 (66.1%) were females. Median [IQR] age and duration on ART were 45 [35–52] years and 72 [48–104] months respectively. Twenty-five out of 26 selected samples from cases were successfully sequenced. Twenty-four samples (96%) had at least one major mutation conferring resistance to HIV drugs, with non-nucleoside analogue reverse transcriptase inhibitor (NNRTI)-resistance associated mutations as the majority (92%). Frequent NNRTI-resistance associated mutations were K103N (n = 11), V106M (n = 5) and G190A (n = 5). Prevalent nucleoside analogue reverse transcriptase inhibitors-resistance associated mutations were M184V (n = 17), K70R (n = 7) and D67N (n = 6). Dual-class resistance was observed in 16 (64%) samples. Thirteen samples (52%) had at least one thymidine analogue-resistance associated mutation (TAM). Three samples (12%) had T69D mutation with at least 1 TAM. Two samples (8%) had at least one mutation associated with protease inhibitor resistance. Age [aOR = 0.94, 95% CI (0.90–0.97), p < 0.001] and occupation [aOR = 0.35, 95% CI (0.12–1.04), p = 0.059] associated with VF. In conclusion, HIV drug resistance is common among people failing antiretroviral therapy. Resistance testing will help to guide switching of HIV drugs.

Characterization of HIV-1 genetic diversity and antiretroviral resistance in the state of Maranhão, Northeast Brazil.

The HIV-1 epidemic in Brazil has been growing in northeast and north regions, particularly an increase in AIDS cases among the younger male population has been observed. This study aims to characterize the HIV-1 genetic diversity and to evaluate its antiretroviral resistance profile among individuals presenting virological failure in the state of Maranhão—Brazil. HIV-1 pol gene sequences from 633 patients on antiretroviral therapy were obtained from the Department of Surveillance, Prevention and Control of Sexually Transmitted Infections, HIV/AIDS and Viral Hepatitis of the Brazilian Ministry of Health. Phylogenetic and recombination analyses were performed to characterize viral genetic diversity. The presence of antiretroviral resistance mutations was assessed using the HIV Drug Resistance Database online platform of Stanford University. A predominance of subtype B (84.5%) was observed, followed by recombinant BF (9.5%), where more than half of the sequences were dispersed in 3 clusters. Antiretroviral resistance was detected in 74.1% of the sequences, and it was significantly higher for nucleoside analogue reverse-transcriptase inhibitors (NRTIs) than for non-nucleoside analogue reverse-transcriptase inhibitors (NNRTIs) and protease inhibitors (PIs). Inference of putative transmissions clusters identified 11 clusters with 22 query sequences (22/633, 3.5%). Thus, we conclude that continuous monitoring of the molecular epidemiology of HIV-1 is essential for prevention strategies, epidemic control, and treatment adequacy.

An Overview of Antiretroviral Agents for Treating HIV Infection in Paediatric Population.

Paediatric Acquired ImmunoDeficiency Syndrome (AIDS) is a life-threatening and infectious disease in which the Human Immunodeficiency Virus (HIV) is mainly transmitted through Mother-To- Child Transmission (MTCT) during pregnancy, labour and delivery, or breastfeeding. This review provides an overview of the distinct therapeutic alternatives to abolish the systemic viral replication in paediatric HIV-1 infection. Numerous classes of antiretroviral agents have emerged as therapeutic tools for downregulation of different steps in the HIV replication process. These classes encompass Non- Nucleoside Analogue Reverse Transcriptase Inhibitors (NNRTIs), Nucleoside/Nucleotide Analogue Reverse Transcriptase Inhibitors (NRTIs/NtRTIs), INtegrase Inhibitors (INIs), Protease Inhibitors (PIs), and Entry Inhibitors (EIs). Co-administration of certain antiretroviral drugs with Pharmacokinetic Enhancers (PEs) may boost the effectiveness of the primary therapeutic agent. The combination of multiple antiretroviral drug regimens (Highly Active AntiRetroviral Therapy - HAART) is currently the standard therapeutic approach for HIV infection. So far, the use of HAART offers the best opportunity for prolonged and maximal viral suppression, and preservation of the immune system upon HIV infection. Still, the frequent administration of high doses of multiple drugs, their inefficient ability to reach the viral reservoirs in adequate doses, the development of drug resistance, and the lack of patient compliance compromise the complete HIV elimination. The development of nanotechnology-based drug delivery systems may enable targeted delivery of antiretroviral agents to inaccessible viral reservoir sites at therapeutic concentrations. In addition, the application of Computer-Aided Drug Design (CADD) approaches has provided valuable tools for the development of anti-HIV drug candidates with favourable pharmacodynamics and pharmacokinetic properties.

Mitophagy in human astrocytes treated with the antiretroviral drug Efavirenz: Lack of evidence or evidence of the lack

Efavirenz (EFV), a first generation non-nucleoside analogue reverse transcriptase inhibitor widely employed in combination antiretroviral therapy regimens over the last 20 years, has been associated with a wide range of neuropsychiatric effects and has also been linked with HIV-associated neurocognitive disorder (HAND). EFV has been reported to alter mitochondrial dysfunction and bioenergetics in different cell types, including astrocytes. Here, we analyzed whether this mitochondrial effect is associated with alterations in autophagy and, more specifically, mitophagy. U251-MG cells were exposed to EFV (10 and 25 μM; 24 h) and the effect was compared with that of CCCP - an uncoupler of the mitochondrial membrane potential and widely-employed in vitro inducer of mitophagy – and those of the known pharmacological stressors rotenone and thapsigargin, selected due to reported similarities with EFV. EFV induces autophagy with functional autophagic flux despite the accumulated p62/SQSTM1. However, it fails to activate canonical mitophagy (according to mitochondrial mass and expression of mitophagy-related proteins). The fact that EFV-exposed cells display decreased levels of TOM20, an outer mitochondrial membrane protein, together with the association of TOM20 with autophagosomes (LC3), points to an alternative form of mitochondrial degradation. Moreover, the perinuclear mitochondrial cluster in EFV-treated cells differs from that displayed with CCCP. Also, in EFV-treated cells, p62 was associated with mitochondria, which may be related to the mito-protective function of this autophagic protein. In conclusion, these findings add to the existing knowledge of the EFV-triggered mitochondrial interference, a mechanism that may be implicated in the adverse CNS events observed in the clinics.

Human Immunodeficiency Virus Drug Resistance: 2018 Recommendations of the International Antiviral Society-USA Panel.

Contemporary antiretroviral therapies (ART) and management strategies have diminished both human immunodeficiency virus (HIV) treatment failure and the acquired resistance to drugs in resource-rich regions, but transmission of drug-resistant viruses has not similarly decreased. In low- and middle-income regions, ART roll-out has improved outcomes, but has resulted in increasing acquired and transmitted resistances. Our objective was to review resistance to ART drugs and methods to detect it, and to provide updated recommendations for testing and monitoring for drug resistance in HIV-infected individuals. A volunteer panel of experts appointed by the International Antiviral (formerly AIDS) Society-USA reviewed relevant peer-reviewed data that were published or presented at scientific conferences. Recommendations were rated according to the strength of the recommendation and quality of the evidence, and reached by full panel consensus. Resistance testing remains a cornerstone of ART. It is recommended in newly-diagnosed individuals and in patients in whom ART has failed. Testing for transmitted integrase strand-transfer inhibitor resistance is currently not recommended, but this may change as more resistance emerges with widespread use. Sanger-based and next-generation sequencing approaches are each suited for genotypic testing. Testing for minority variants harboring drug resistance may only be considered if treatments depend on a first-generation nonnucleoside analogue reverse transcriptase inhibitor. Different HIV-1 subtypes do not need special considerations regarding resistance testing. Testing for HIV drug resistance in drug-naive individuals and in patients in whom antiretroviral drugs are failing, and the appreciation of the role of testing, are crucial to the prevention and management of failure of ART.

High prevalence of HIV-1 transmitted drug-resistance mutations from proviral DNA massively parallel sequencing data of therapy-naïve chronically infected Brazilian blood donors.

BackgroundAn improved understanding of the prevalence of low-abundance transmitted drug-resistance mutations (TDRM) in therapy-naïve HIV-1–infected patients may help determine which patients are the best candidates for therapy. In this study, we aimed to obtain a comprehensive picture of the evolving HIV-1 TDRM across the massive parallel sequences (MPS) of the viral entire proviral genome in a well-characterized Brazilian blood donor naïve to antiretroviral drugs.Materials and methodsThe MPS data from 128 samples used in the analysis were sourced from Brazilian blood donors and were previously classified by less-sensitive (LS) or “detuned” enzyme immunoassay as non-recent or longstanding HIV-1 infections. The Stanford HIV Resistance Database (HIVDBv 6.2) and IAS-USA mutation lists were used to interpret the pattern of drug resistance. The minority variants with TDRM were identified using a threshold of ≥ 1.0% and ≤ 20% of the reads sequenced. The rate of TDRM in the MPS data of the proviral genome were compared with the corresponding published consensus sequences of their plasma viruses.ResultsNo TDRM were detected in the integrase or envelope regions. The overall prevalence of TDRM in the protease (PR) and reverse transcriptase (RT) regions of the HIV-1 pol gene was 44.5% (57/128), including any mutations to the nucleoside analogue reverse transcriptase inhibitors (NRTI) and non-nucleoside analogue reverse transcriptase inhibitors (NNRTI). Of the 57 subjects, 43 (75.4%) harbored a minority variant containing at least one clinically relevant TDRM. Among the 43 subjects, 33 (76.7%) had detectable minority resistant variants to NRTIs, 6 (13.9%) to NNRTIs, and 16 (37.2%) to PR inhibitors. The comparison of viral sequences in both sources, plasma and cells, would have detected 48 DNA provirus disclosed TDRM by MPS previously missed by plasma bulk analysis.ConclusionOur findings revealed a high prevalence of TDRM found in this group, as the use of MPS drastically increased the detection of these mutations. Sequencing proviral DNA provided additional information about TDRM, which may impact treatment decisions. The overall results emphasize the importance of continuous monitoring.

HIV-1 drug resistance transmission threshold survey in Dehong prefecture of Yunnan province, 2015

Objective: To study the HIV-1 drug resistance transmission level in HIV infected persons receiving no antiviral therapy in Dehong prefecture of Yunnan province in 2015. Methods: A total of 72 plasma samples were collected from recently reported HIV-infected persons aged 16-25 years in Dehong from January to July 2015 for drug resistance gene detection. Results: Forty eight samples were successfully sequenced and analyzed. Among them, 31.2% (15/48) were from Chinese, and 68.8% (33/48) were from Burmese. Based on pol sequences, HIV genotypes included URF (52.08%, 25/48), CRF01_AE (16.67%, 8/48), RF07_BC (10.42%, 5/48), subtype B (6.25%, 3/48), subtype C (6.25%, 3/48), CRF57_BC (6.25%, 3/48) and CRF08_BC (2.08%, 1/48). One drug resistant mutation site to non-nucleoside analog reverse transcriptase inhibitor (NNRTI) and two drug resistant mutation site to nucleoside analog reverse transcriptase inhibitor (NRTI) were detected in four sequences. Based on the statistical method of HIV drug resistance threshold survey, the prevalence of HIV-1 drug resistant strain was 5%-15%. Conclusions: The proportion of Burmese among newly reported HIV-infected individuals aged 16-25 years in Dehong in 2015 was higher. HIV-1 genetic diversity was found in Dehong. The prevalence of HIV-1 drug resistant strain had reached a moderate level in Dehong.

Chemical structure and correlation analysis of HIV-1 NNRT and NRT inhibitors and database-curated, published inhibition constants with chemical structure in diverse datasets

Human immunodeficiency virus (HIV-1) reverse transcriptase is a major target for designing anti-HIV drugs. Developed inhibitors are divided into non-nucleoside analog reverse-transcriptase inhibitors (NNRTIs) and nucleoside analog reverse-transcriptase inhibitors (NRTIs) depending on their mechanism. Given that many inhibitors have been studied and for many of them binding affinity constants have been calculated, it is beneficial to analyze the chemical landscape of these families of inhibitors and correlate these inhibition constants with molecular structure descriptors. For this, the HIV-1 RT data was retrieved from the ChEMBL database, carefully curated, and original literature verified, grouped into NRTIs and NNRTIs, analyzed using a hierarchical scaffold classification method and modelled with best multi-linear regression approach. Analysis of the HIV-1 NNRTIs subset results in ten different common structural parent types of oxazepanone, piperazinone, pyrazine, oxazinanone, diazinanone, pyridine, pyrrole, diazepanone, thiazole, and triazine. The same analysis for HIV-1 NRTIs groups structures into four different parent types of uracil, pyrimide, pyrimidione, and imidazole. Each scaffold tree corresponding to the parent types has been carefully analyzed and examined, and changes in chemical structure favorable to potency and stability are highlighted. For both subsets, descriptive and predictive QSAR models are derived, discussed and externally validated, revealing general trends in relationships between molecular structure and binding affinity constants in structurally diverse datasets. Data and QSAR models are available at the QsarDB repository (http://dx.doi.org/10.15152/QDB.202).

New Treatment Options

None of the studies conducted on people who have reduced the number of antivirals taken in their regimen have shown good results. Research has consistently shown that these people have an increased viral load count when one or more drugs are discontinued. Results from a French study show some promise in switching from a protease inhibitor to a nonnucleoside analogue reverse transcriptase inhibitor (NNRTI) such as Viramune (Nevirapine) or Sustiva (efavirenz). Fifteen out of sixteen participants maintained viral load levels below 200 copies when they changed to an NNRTI regimen. The one person whose viral load increased had taken an NNRTI drug before, although its use was prohibited in eligibility requirements. The strategy may work for people at varying stages of the disease, but larger studies are needed to confirm the results. Also, a fifth protease inhibitor, Amprenavir (Agenerase) has received FDA approval. Trial results are summarized, and side effects and drug interactions with Amprenavir are described.

High prevalence of transmitted drug resistance in acute HIV-infected Thai men who have sex with men.

: As use of antiretroviral therapy in Thailand increases, so does the potential for transmission of drug-resistant HIV. We describe the prevalence of WHO surveillance drug resistance mutations among 120 subjects who underwent genotypic testing during acute HIV infection in Bangkok, Thailand. In this cohort of predominantly men who have sex with men, we observed an overall transmitted drug resistance prevalence of 9.2%, including nucleoside/nucleotide analog reverse transcriptase inhibitor 5.0%, nonnucleoside analog reverse transcriptase inhibitor 3.4%, and protease inhibitor 3.4%. These prevalence estimates are higher than previous reports of transmitted drug resistance in Thailand. Baseline drug resistance testing may be warranted, particularly among men who have sex with men.

Mitochondrial (dys)function - a factor underlying the variability of efavirenz-induced hepatotoxicity?

The non-nucleoside analogue reverse transcriptase inhibitor efavirenz is associated with hepatic toxicity and metabolic disturbances. Although the mechanisms involved are not clear, recent evidence has pinpointed a specific mitochondrial action of efavirenz accompanied by the induction of an endoplasmic reticulum (ER) stress/unfolded protein response in human hepatic cells. The aim of this study was to further investigate the involvement of this organelle by evaluating efavirenz's effects in cells lacking functional mitochondria (rho°) and comparing them with those of the typical mitotoxic agent rotenone, a standard complex I inhibitor, and the ER stress inducer thapsigargin. Hep3B rho(+) and rho° cells were treated with clinically relevant concentrations of efavirenz, then mitochondrial function and cytotoxicity were studied using standard cell biology techniques. Efavirenz-treated rho° cells exhibited a substantial reduction in parameters indicative of mitochondrial interference, such as increased superoxide production, mitochondrial mass/morphology alterations and enhanced expression of LONP, a highly conserved mitochondrial protease. In line with these results, the cytotoxic effect (cell number, chromatin condensation, cell cycle alterations and induction of apoptosis) of efavirenz was less pronounced in Hep3B respiration-depleted cells than in wild-type cells. The effect of efavirenz was both similar and different from those of two distinct mitochondrial stressors, thapsigargin and rotenone. Cells lacking normal mitochondria (rho°) are less vulnerable to efavirenz. Our results provide further evidence that the hepatic damage induced by efavirenz involves acute interference with mitochondria and extend our knowledge of the response of mitochondria/ER to a stress stimulus.

Longer Use of Combination Antiretroviral Therapy Associated with Reduced Risk Of Cervical HPV

Women infected with HIV may have a lower risk of testing positive for cervical human papillomavirus (HPV) if they have been taking combination antiretroviral therapy (cART) for a longer period of time, according to a prospective cohort study conducted in South Africa. (1) Relative to peers who were not receiving this therapy, study participants who were receiving cART had a reduction of two-thirds in the unadjusted odds of HPV types associated with a high risk of cervical cancer and a reduction of one-half in the unadjusted odds of HPV 16, one of the main cancer-causing types. Although these associations were no longer statistically significant after adjustment for covariates, duration of therapy remained an important indicator of risk: With each additional month that a woman used cART, the adjusted likelihood of testing positive fell by 5% and 6%, respectively, for high-risk types and for HPV 16. Between November 2009 and October 2011, investigators enrolled in the study non-pregnant, cancer-free South African women who were infected with HIV and had never taken cART. During twice-yearly follow-up visits, the women provided clinical, obstetric and sexual behavior data; underwent a Pap test; and gave blood samples for assessment of CD4 cell count and HIV viral load, and cervical samples for HIV and HPV DNA testing. The investigators used bivariate analyses to compare baseline characteristics between women who did and did not initiate cART, and modeled the probability of detection of HPV using multivariate logistic regression analysis as a function of whether women were on cART at a given visit and of the length of time they had been on this therapy. The 300 women studied were 35 years old, on average. Overall, 68% initiated cART after meeting the criteria in government guidelines; all were started on a regimen containing a non-nucleoside analogue reverse transcriptase inhibitor, standard practice at the time. About 46% of women who initiated cART and 65% of those who did not were black, and the majority (69% and 80%, respectively) had a partner. Mean duration of follow-up was 19 months among those who initiated cART and 12 months among those who did not. On average, the women who started cART stayed on this therapy for 16 months. Results showed that 94% of women tested positive for at least one high-risk type of HPV (type 16, 18, 31, 33, 35, 39, 45, 52 or 58) at some time during follow-up, and 42% specifically tested positive for HPV 16. In unadjusted analyses, relative to peers who were not using cART, women who were had a roughly 80% reduction in the odds of testing positive for any type of HPV (odds ratio, 0. …

Lopinavir/ritonavir en nuevas estrategias de tratamiento antirretroviral de inicio

According to evidence from randomized controlled trials and epidemiological data, the antiretroviral treatment (ART) of choice has consisted of the combination of 2 nucleoside analog reverse-transcriptase inhibitors (NRTI) plus 1 non-nucleoside analog reverse-transcriptase inhibitor (NNRTI) or a protease inhibitor (PI) for more than 17 years. There are several unresolved issues, notably the toxocity associated with NRTI, especially thymidine analogs, and the possibility of cross resistance, which may affect subsequent treatment. The development of new antiretroviral drugs with simpler dosing regimens and lower toxicity has led to evaluation of innovative strategies such as dual therapy for initial ART in treatment-naive, with the aim of preventing long-term toxicity and increasing treatment adherence. Despite encouraging results, some combinations have proven unsatisfactory. The strategies with favorable results to date consist of twice-daily lopinavir/ritonavir (LPV/r)-based regimens, those in the PROGRESS (LPV/r + raltegravir) and GARDEL (LPV/r + lamivudine) trials, and the combination of darunavir and raltegravir (NEAT 001 trial), although the latter observed a higher tendency (statistically nonsignificant) to virological failure in the dual combination arm. These trials were based on the use of NRTI-sparing regimens consisting of 2–3 fully- active agents for highly-active ART in treatment-naïve HIV-positive patients. Recent studies provide evidence supporting the use of NRTI-sparing regimens in HIV-infected patients with failure to an initial NNRTI-based ART regimen. The present review will discuss only LPV/r-based innovative strategies in initial ART regimens.

Vitamin E concentrations in adults with HIV/AIDS on highly active antiretroviral therapy.

HIV/AIDS patients are probably more predisposed to vitamin E deficiency, considering that they are more exposed to oxidative stress. Additionally, there are an extensive number of drugs in the highly active antiretroviral therapy (HAART) regimens that may interfere with vitamin E concentrations. The objective of this study was to compare serum concentrations of alpha-tocopherol in 182 HIV/AIDS patients receiving different HAART regimens. The patients were divided into three groups according to regimen: nucleoside analog reverse-transcriptase inhibitors (NRTIs) + non-nucleoside analog reverse-transcriptase inhibitors (NNRTIs); NRTIs + protease inhibitors + ritonavir; NRTIs + other classes. Alpha-tocopherol was assessed by high-performance liquid chromatography. Multiple linear regression analysis was used to evaluate the effects of HAART regimen, time of use, and compliance with the regimen on alpha-tocopherol concentrations. Alpha-tocopherol concentrations were on average 4.12 μmol/L lower for the NRTIs + other classes regimen when compared to the NRTIs + NNRTIs regimen (p = 0.037). A positive association (p < 0.001) was observed between alpha-tocopherol and cholesterol concentrations, a finding due, in part, to the relationship between liposoluble vitamins and lipid profile. This study demonstrated differences in alpha-tocopherol concentrations between patients using different HAART regimens, especially regimens involving the use of new drugs. Long-term prospective cohort studies are needed to monitor vitamin E status in HIV/AIDS patients since the beginning of treatment.

Factors associated with mortality among persistently viraemic triple-antiretroviral-class-experienced patients receiving antiretroviral therapy in the HIV Outpatient Study (HOPS).

Identifying factors associated with mortality for HIV-infected patients with persistent viraemia despite antiretroviral (ARV) therapy may inform diagnostic and treatment strategies. We analysed data from viraemic triple-ARV-class-experienced HIV Outpatient Study patients seen during 1 January 1999 to 31 December 2012 who, despite treatment that included ARVs from three major drug classes [nucleoside analogue reverse transcriptase inhibitors, non-nucleoside analogue reverse transcriptase inhibitors and protease inhibitors (PIs)], had plasma HIV RNA levels [viral load (VL)] >1000 copies/mL ['triple ARV class failure' (TCF)]. The baseline was defined as the date of meeting the TCF criteria during 1999-2008. We identified factors associated with mortality using Cox regression. Of 597 patients who met the TCF criteria (median follow-up after baseline 4.9 years), 115 (19.3%) died. Baseline factors associated with mortality were age per 10 years [hazard ratio (HR) 1.61, 95% CI 1.28-2.02], risk of HIV from use of injection drugs (HR 1.81, 95% CI 1.10-2.98), CD4+ T cell count <200 cells/mm(3) (HR 3.68, 95% CI 2.41-5.62), VL ≥5.0 log10 copies/mL (HR 2.91, 95% CI 1.88-4.49) and receiving a first combination ARV therapy regimen that was PI-based (HR 2.44, 95% CI 1.47-4.06); receiving a novel ARV agent during follow-up (HR 0.45, 95% CI 0.22-0.93) was protective. Genotypic resistance testing results were available for 274 (45.9%) of the TCF patients, of whom 47 (17.2%) died. In this group, factors associated with death were increasing age (HR 1.94, 95% CI 1.36-2.78, per 10 year increment), risk of HIV from use of injection drugs (HR 2.71, 95% CI 1.37-5.39), baseline VL ≥5.0 log10 copies/mL (HR 5.35, 95% CI 2.82-10.1) and receiving PI-based first combination ARV therapy regimen (HR 3.20, 95% CI 1.25-8.17). No HIV mutations or combinations of mutations were significantly associated with survival. Factors significantly associated with mortality risk among TCF patients who received ongoing ARV therapy included traditional clinical predictors but not the presence, type or number of HIV genetic mutations. The use of novel ARV drugs by these ARV therapy-experienced patients was associated with an improved survival.