Non-nucleoside Reverse Transcriptase Research Articles

Alkaloids as Potential Anti-HIV Agents.

Alkaloids are nitrogen-containing compounds that are naturally occurring and have a variety of biological activities, including antimicrobial properties. In this study, the authors used a molecular docking approach to evaluate the anti-HIV potential of 64 alkaloids. The authors used the Molegro Virtual Docker software to dock the alkaloids into the active sites of three HIV enzymes: protease, integrase, and non-nucleoside reverse transcriptase (NNRT). The docking scores were used to assess the potential of the alkaloids to inhibit the enzymes. The results showed the alkaloids to have good potential to inhibit the enzymes. Tubocurarine and reserpine were found to be the most potent alkaloids, with docking scores of -123.776 and - 114.956, respectively. The authors concluded that tubocurarine and reserpine could be further promoted as potential lead molecules for the development of new anti-HIV drugs.

The Hepatoprotective Effects of Moringa oleifera against Antiretroviral-Induced Cytotoxicity in HepG2 Cells: A Review.

The untreated human immunodeficiency virus (HIV), a lentivirus species that attacks immune cells (CD4+ T cells), causes acquired immunodeficiency syndrome (AIDS). HIV-positive people manage HIV/AIDS by using antiretroviral therapy (ART). The ART treatment regimen contains two nucleoside reverse transcriptase inhibitors (NRTIs) and one non-nucleoside reverse transcriptase inhibitor/integrase strand transfer inhibitor. Tenofovir, an NRTI approved for managing HIV infection, is associated with hepatic steatosis and lactic acidosis, which are linked to mitochondrial toxicity and oxidative stress. Due to side-effects associated with ART, people living with HIV often use medicinal plants or a combination of medicinal plants with ART to promote adherence and diminish the side-effects and cytotoxicity. The Moringa oleifera (MO) tree from the family of Moringaceae is among the medicinal trees studied in managing HIV/AIDS in sub-Saharan Africa. The MO tree extracts have been reported to have inhibitory activity primarily against HIV due to their bioactive compounds. However, there is a scarcity of knowledge about the use of the MO tree amongst HIV/AIDS patients receiving ART in South Africa and its effect on patient compliance and outcomes. Thus, this review aims to outline the impact of MO aqueous leaf extract on oxidative stress and antioxidant responses in human HepG2 liver cells after exposure to antiretrovirals such as tenofovir. The review will contribute to a comprehensive understanding of the potential protective effect of MO aqueous leaf extract on tenofovir-induced cytotoxicity.

Real-world effectiveness of WHO recommended first-line antiretroviral therapies: a cohort study from a middle-income country

ABSTRACT We estimate the effectiveness of antiretroviral therapy (ART) among individuals receiving HIV care in Rio de Janeiro, Brazil. Adults (18y+) initiating ART between Jan/2008 and Dec/2018 (follow-up through Dec/2020) were included. First-line ART (two nucleoside reverse transcriptase inhibitors plus one antiretroviral from another class) was categorized into four categories: non-nucleoside reverse transcriptase inhibitor/NNRTI-based, protease inhibitor/PI-based, integrase strand transfer inhibitor/INSTI-based, and single-tablet regimen (STR, Tenofovir 300mg + Lamivudine 300mg + Efavirenz 600mg). Effectiveness (viral load ≤50 copies/µL) was evaluated at 6(3–9) and 12(9–15) months from ART initiation. Bayesian logistic regression models were used to quantify the association between exposure and outcomes while accounting for missing data. Overall, 1863(57%), 652(19.9%), 412(12.6%), and 342(10.5%) individuals used, respectively, NNRTI-based, PI-based, INSTI-based regimens, and STR. Compared to NNRTIs, the odds of viral suppression with INSTI-based regimens was 76% higher (adjusted OR:1.76, 95%CI:1.23–2.51) at six months but no higher at 12 months. Older age, higher education, CD4 count ≥500 cells/mm3 and viral load <100,000 copies/µL at ART initiation increased the odds of viral suppression. Viral suppression at six months was the strongest predictor of viral suppression at 12 months. These results highlight population groups that could benefit from close monitoring during the first year of ART.

Adverse perinatal outcomes associated with prenatal exposure to protease-inhibitor-based versus non-nucleoside reverse transcriptase inhibitor-based antiretroviral combinations in pregnant women with HIV infection: a systematic review and meta-analysis

BackgroundAbout 1.3 million pregnant women lived with HIV and were eligible to receive antiretroviral therapy (ART) worldwide in 2021. The World Health Organization recommends protease inhibitors (PI)-based regimen as second or third-line during pregnancy. With remaining pregnant women exposed to PIs, there is still an interest to assess whether this treatment affects perinatal outcomes. Adverse perinatal outcomes after prenatal exposure to PI-based ART remain conflicting: some studies report an increased risk of preterm birth (PTB) and low-birth-weight (LBW), while others do not find these results. We assessed adverse perinatal outcomes associated with prenatal exposure to PI-based compared with non-nucleoside reverse transcriptase (NNRTI)-based ART.MethodsWe performed a systematic review searching PubMed, Reprotox, Clinical Trial Registry (clinicaltrials.gov) and abstracts of HIV conferences between 01/01/2002 and 29/10/2021. We used Oxford and Newcastle-Ottawa scales to assess the methodological quality. Studied perinatal outcomes were spontaneous abortion, stillbirth, congenital abnormalities, PTB (< 37 weeks of gestation), very preterm birth (VPTB, < 32 weeks of gestation), LBW (< 2500 grs), very low-birth-weight (VLBW, < 1500 g), small for gestational age (SGA) and very small for gestational age (VSGA). The association between prenatal exposure to PI-based compared to NNRTI-based ART was measured for each adverse perinatal outcome using random-effect meta-analysis to estimate pooled relative risks (RR) and their corresponding 95% confidence intervals (CI). Pre-specified analyses were stratified according to country income and study quality assessment, and summarized when homogeneous.ResultsOut of the 49,171 citations identified, our systematic review included 32 published studies, assessing 45,427 pregnant women. There was no significant association between prenatal exposure to PIs compared to NNRTIs for VPTB, LBW, SGA, stillbirth, and congenital abnormalities. However, it was inconclusive for PTB, and PI-based ART is significantly associated with an increased risk of VSGA (sRR 1.41 [1.08-1.84]; I2 = 0%) compared to NNRTIs.ConclusionsWe did not report any significant association between prenatal exposure to PIs vs NNRTIs-based regimens for most of the adverse perinatal outcomes, except for VSGA significantly increased (+ 41%). The evaluation of antiretroviral exposure on pregnancy outcomes remains crucial to fully assess the benefice-risk balance, when prescribing ART in women of reproductive potential with HIV.PROSPERO numberCRD42022306896.

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.

117. Trends in Four-class HIV Drug Resistance in Treatment-experienced Patients in the United States

BackgroundDespite the availability of potent antiretroviral therapy, only 56% of people living with HIV in the US were virally suppressed in 2018. Drug resistance can hinder suppression, especially among treatment-experienced patients, in whom the prevalence of 4-class drug resistance (4CR) is unknown.MethodsGenotypic results of PhenoSense GT® Plus Integrase (Monogram Biosciences, South San Francisco, CA) obtained from Apr 2014 to Dec 2020 were used to assign susceptibility to nucleos(t)ide reverse transcriptase, non-nucleoside reverse transcriptase, integrase, and protease inhibitors (NRTIs, NNRTI, INIs, and PIs). Data were analyzed using summary statistics, 2 proportion Z test, one-way ANOVA and Tukey-Kramer; p < 0.05 was significant.ResultsAmong 13,651 patients with 15,372 tests, median age was 43 years; most had HIV-1 subtype B infection (95.09%), followed by AG (1.32%).Among 12,303 patients with only one test, 4CR prevalence was 1.55%. Among 1,348 patients with more than one test, 4CR was seen in 3.64% of patients, and in 4.60% if cumulative resistance reports were assembled for each patient. Patients with 4CR were significantly older than those with less resistance.The incidence of 4CR fluctuated, with a decline from 2.61% of patients tested in 2014 to 1.38% in 2017, an increase to 2.36% in 2018, and a decline to 1.56% in 2020. Among patients with more than one test, 21.01% gained resistance to a drug in a new class over an average of 19.5 months.Most new resistance each year was to NNRTIs, followed by NRTIs, INIs, and PIs. The incidence of PI resistance declined for PIs from 13.34% of patients tested in 2014 to 11.82% in 2020, but increased for INIs from 14.56% in 2014 to 16.49% in 2020. The regimen expected to be suppressive in the greatest proportion of patients was dolutegravir + darunavir/cobicistat (94.51%).ConclusionThe prevalence of 4CR has declined over time, but remains clinically relevant, particularly in older patients who may struggle with adherence due to complex regimens, comorbidities and polypharmacy. New drug classes may benefit this group. The concurrent increase in INI and decline in PI resistance may reflect changes in prescribing practices. Drug resistance may be underestimated unless cumulative resistance is determined.Disclosures Dusica Curanovic, PhD, Monogram Biosciences (Employee) Johnny Lai, BS, Monogram Biosciences (Employee, Shareholder) Christos J. Petropoulos, PhD, Monogram Biosciences (Employee, Shareholder) Charles M. Walworth, MD, Monogram Biosciences (Employee, Shareholder)

Group counselling for adherence support among young people failing first-line antiretroviral therapy in Zimbabwe.

BackgroundSub-optimal adherence to antiretroviral therapy (ART) is reportedly worse amongst young people living with HIV (YPLHIV). Group adherence counselling can be useful to improve adherence.ObjectivesWe evaluated an enhanced adherence counselling group intervention (EACGI) amongst YPLHIV failing a non-nucleoside reverse transcriptase (NNRTI)-based first-line ART regimen.MethodThis was a retrospective cohort study using routinely collected data of YPLHIV failing NNRTI-based first-line ART. Patients with confirmed virological failure were referred for EACGI, a 12-week curriculum of weekly, 1.5-h sessions accommodating 8–15 people per group. It aimed to facilitate readiness to switch to second-line ART and improve adherence through a mental health intervention. Viral loads of HIV were measured pre-EACGI; at baseline; 3, 6 and 12 months post switch.ResultsFifty-seven patients aged 13–25 years were invited to EACGI and followed for up to 48 weeks. Thirty-three (58%) patients attended at least four sessions, whilst 24 (42%) attended none. Amongst those who attended none, two (8%) were transferred out, three (13%) were lost to follow-up and two (8%) had died by week 48 of follow-up, whilst all who attended were still in care. By week 48, amongst patients still in care, 29%, 44% and 67% of those who attended no sessions, 4–9 and 10–12 sessions, respectively, had viral loads of < 50 copies/mL.ConclusionAn EACGI is a promising intervention for YPLHIV failing ART prior to treatment switch, leading to improved adherence. This study’s findings support the need for further enquiry into rigorous, evidence-based multilevel adherence interventions that are acceptable and effective for YPLHIV.

Coverage of maternal viral load monitoring during pregnancy in South Africa: Results from the 2019 national Antenatal HIV Sentinel Survey.

Objectives:South Africa has made remarkable progress in increasing the coverage of antiretroviral therapy (ART) among pregnant women; however, viral suppression among pregnant women receiving ART is reported to be low. Access to routine viral load testing is crucial to identify women with unsuppressed viral load early in pregnancy and to provide timely intervention to improve viral suppression. This study aimed to determine the coverage of maternal viral load monitoring nationally, focusing on viral load testing, documentation of viral load test results, and viral suppression (viral load < 50 copies/mL). At the time of this study, the first-line regimen for women initiating ART during pregnancy was non-nucleoside reverse transcriptase (NNRTI)-based regimen.Methods:Between 1 October and 15 November 2019, a cross-sectional survey was conducted among 15- to 49-year-old pregnant women attending antenatal care in 1589 nationally representative public health facilities. Data on ART status, viral load testing and viral load test results were extracted from medical records. Logistic regression was used to examine factors associated with coverage of viral load testing.Results:Of 8112 participants eligible for viral load testing, 81.7% received viral load testing, and 94.1% of the viral load test results were documented in the medical records. Of those who had viral load test results documented, 74.1% were virally suppressed. Women initiated on ART during pregnancy and who received ART for three months had lower coverage of viral load testing (73%) and viral suppression (56.8%) compared with women initiated on ART before pregnancy (82.8% and 76.1%, respectively). Initiating ART during pregnancy rather than before pregnancy was associated with a lower likelihood of receiving a viral load test during pregnancy (adjusted odds ratio = 1.6, 95% confidence interval: 1.4–1.8).Conclusions:Viral load result documentation was high; viral load testing could be improved especially among women initiating ART during pregnancy. The low viral suppression among women who initiated ART during pregnancy despite receiving ART for three months highlights the importance of enhanced adherence counselling during pregnancy. Our finding supports the WHO recommendation that a Dolutegravir-containing regimen be the preferred regimen for women who are newly initiating ART during pregnancy for more rapid viral suppression.

Do integrase inhibitors affect immune restoration?

In The Lancet HIV, Sergio Serrano-Villar and colleagues 1 Serrano-Villar S Martínez-Sanz J Ron R et al. Effects of first-line antiretroviral therapy on the CD4/CD8 ratio and CD8 cell counts in CoRIS: a prospective multicentre cohort study. Lancet HIV. 2020; 7: e565-e573 Summary Full Text Full Text PDF PubMed Scopus (4) Google Scholar report that initiation of a integrase strand-transfer inhibitor (INSTI)-based regimen in patients lead to greater CD4/CD8 ratio recovery compared with a non-nucleoside reverse transcriptase or protease inhibitor-based strategy. To date, this is the largest study to provide such results. Effects of first-line antiretroviral therapy on the CD4/CD8 ratio and CD8 cell counts in CoRIS: a prospective multicentre cohort studyThis study provides new evidence that reinforces the positioning of INSTI-based therapies as a first choice and underlines the importance of analysing the effects of therapeutic interventions on biomarkers linked with morbidity and mortality beyond the plasma HIV RNA and the CD4 cell counts. Full-Text PDF

Uracil-Containing Heterodimers of a New Type: Synthesis and Study of Their Anti-Viral Properties.

Widespread latent herpes viral infections within a population can lead to the development of co-infections in HIV-infected patients. These infections are not particularly dangerous for healthy individuals and often occur with minimal symptoms, but for those who are immunocompromised, these infections can accelerate the acute phase of HIV infection and AIDS. Thus, the idea of designing compounds that could combine activity against HIV and co-infections would seem promising. In that regard, eleven compounds were synthesized that represent conjugates of non-nucleoside HIV reverse transcriptase inhibitors and nucleoside inhibitors of the herpes family viruses with the hope that these novel heterodimers will result in dual activity against HIV and concomitant herpes virus infections.

Efficacy and safety of a single-tablet regimen containing tenofovir disoproxil fumarate 300 mg, lamivudine 300 mg and efavirenz 400 mg as a switch strategy in virologically suppressed HIV-1-infected subjects on nonnucleoside reverse transcriptase inhibitor-containing first-line antiretroviral therapy in Pune, India.

ObjectivesAs per National AIDS Control Organization (NACO) estimates, there are 2.1 million people living with HIV (PWH) in India, of whom 1.2 million are on first‐line antiretroviral therapy (ART). This study explored the use of a single‐tablet regimen containing tenofovir disoproxil fumarate 300 mg + lamivudine 300 mg + efavirenz 400 mg (TLE400 STR) as a first‐line switch strategy in PWH in Pune, India.MethodsThis retrospective cohort study was conducted in private sector ART clinics in three tertiary‐level hospitals in Pune, India. PWH > 12 years of age (n = 502) who initiated first‐line ART (predominantly TLE600 STR), completed ≥ 6 months of follow‐up and achieved virological suppression [plasma viral load (VL) < 1000 HIV‐1 RNA copies/mL] were identified and switched to TLE400 STR. The virological and immunological efficacy of TLE400 STR at 6 and 12 months of follow‐up were noted. Grade 3/4 adverse events (especially efavirenz‐related neuropsychiatric adverse events) leading to regimen discontinuation were also noted.ResultsOf 502 PWH who switched to TLE400 STR, complete virological suppression (VL < 20 copies/mL) was maintained in more than 97% of patients at follow‐up. TLE400 STR was successful in maintaining CD4 counts within the range observed at the start of the regimen. Grade 3/4 adverse events leading to TLE400 STR discontinuation were seen in 11 (2.2%) patients. Virological failure (VL > 1000 copies/mL) and treatment regimen failure were seen in six (1.2%) and 49 (9.8%) subjects, respectively.ConclusionsTLE400 STR exhibits excellent efficacy and safety as a switch strategy and should be introduced in the Indian National ART Program, especially for PWH who are virologically suppressed on TLE600 STR.

Efavirenz as a potential drug for the treatment of triple-negative breast cancers.

In contrast to hormone receptor driven breast cancer, patients presenting with triple-negative breast cancer (TNBC) often have limited drug treatment options. Efavirenz, a non-nucleoside reverse transcriptase (RT) inhibitor targets abnormally overexpressed long interspersed nuclear element 1 (LINE-1) RT and has been shown to be a promising anticancer agent for treating prostate and pancreatic cancers. However, its effectiveness in treating patients with TNBC has not been comprehensively examined. In this study, the effect of Efavirenz on several TNBC cell lines was investigated by examining several cellular characteristics including viability, cell division and death, changes in cell morphology as well as the expression of LINE-1. The results show that in a range of TNBC cell lines, Efavirenz causes cell death, retards cell proliferation and changes cell morphology to an epithelial-like phenotype. In addition, it is the first time that a whole-genome RNA sequence analysis has identified the fatty acid metabolism pathway as a key regulator in this Efavirenz-induced anticancer process. In summary, we propose Efavirenz is a potential anti-TNBC drug and that its mode of action can be linked to the fatty acid metabolism pathway.

HIV-1 molecular epidemiology and drug resistance-associated mutations among treatment-na\xefve blood donors in China

Surveillance of human immunodeficiency virus (HIV) molecular diversity and drug resistance-associated mutations (DRMs) among treatment-naïve blood donors is critical for monitoring viral evolution and blood safety. From 2016-2017, 199 plasma samples were collected from 24 blood centers and confirmed as HIV viral load positive or serologically reactive in National Centers for Clinical Laboratories (NCCL), of which 179 were sequenced and subtyped in the gag, protease (PR)-reverse transcriptase (RT), integrase (IN) and/or envelope (env) regions. DRMs in PR-RT and IN regions were analyzed in Stanford HIVdb Program. The majority of subtypes were circulating recombinant form (CRF) 07_BC (34.6%) and CRF01_AE (32.4%); many unique recombinant forms (URFs) (39, 21.8%) and other rare CRFs were observed in the study. Notably, CRF02_AG and CRF06_cpx strains typically found in Africa were firstly identified amongst Chinese blood donors. DRMs were common, with 28 of 179 (15.6%) specimens carrying DRMs, including the PR N88S and RT K103N mutations, which have been implicated in elevated resistance to antiretroviral drugs. Furthermore, 4 HIV-1 isolates (2.4%, 4/168) had surveillance drug-resistance mutation (SDRM), including 3 nonnucleosidereverse transcriptase inhibitors (NNRTI) SDRMs (1 K101E, 2 K103N) and 1 protease inhibitor (PI) SDRM (M46I). The HIV viral diversity among blood donors observed in this study suggest that ongoing HIV-1 recombination is becoming progressively complex in China, and lots of DRMs found in the study exacerbate the primary drug resistance landscape, which highlight the necessity of timely genotypic drug resistance monitoring and molecular surveillance of HIV-1 among blood donors.

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.

The association of nadir CD4-T cell count and endothelial dysfunction in a healthy HIV cohort without major cardiovascular risk factors.

Objectives:HIV-infected population may have increased risk of cardiovascular disease. The prevalence of traditional cardiovascular disease risk factors such as hypertension, diabetes and dyslipidemia in HIV-infected individuals has made it difficult to assess the direct effects of HIV and immune factors on endothelial dysfunction and associated increased risk of atherosclerosis. The purpose of this study was to investigate indicators of endothelial dysfunction in an HIV cohort without hypertension and diabetes.Methods:We studied 19 HIV-infected patients between the ages of 25–76 years old with effectively suppressed viral load and without diagnosis of hypertension or diabetes. Endothelial function was measured by digital thermal monitoring of vascular reactivity using the VENDYS technique. Endothelial function was reported as vascular reactivity index. Systolic blood pressure and diastolic blood pressure at the time of VENDYS test were measured and latest lipid panels were recorded. The association between vascular reactivity index and CD4-T cells count, different antiretroviral therapy types (non-nucleoside reverse transcriptase, nucleoside reverse transcriptase, protease inhibitors, integrase inhibitors), vitamins use, systolic blood pressure, diastolic blood pressure, high-density lipoprotein cholesterol and low-density lipoprotein cholesterol was investigated.Results:Mean vascular reactivity index was 1.87 ± 0.53. Vascular reactivity index, marker of endothelial dysfunction, showed a significant correlation with lower nadir CD4 count (p = 0.003) as well as low-density lipoprotein cholesterol (p = 0.02). No additional significant correlation between vascular reactivity index and the rest of the investigated variables was found.Conclusion:Vascular reactivity index, a clinical predictor of endothelial dysfunction, is associated with lower nadir CD4-T cell and low-density lipoprotein cholesterol in HIV-infected men with no history of hypertension or diabetes and before clinical evidence of cardiovascular disease.

Is immune recovery different depending on the use of integrase strand transfer inhibitor-, non-nucleoside reverse transcriptase- or boosted protease inhibitor-based regimens in antiretroviral-naive HIV-infected patients?

To analyse whether integrase inhibitor (InSTI)-based regimens achieve better immunological recovery than NNRTI- or boosted PI (bPI)-based regimens as initial ART. In a retrospective analysis, we selected patients who initiated ART with two NRTIs plus an InSTI, an NNRTI or a bPI and maintained both the same 'third drug' and an HIV-RNA <50 copies/mL in ≥95% of determinations once undetectable viral load had been achieved. We compared CD4+ count, %CD4+ and CD4+/CD8+ ratio recovery over 2 years. Data were analysed using mixed-effects regression models for repeated measures. Of the 836 patients included, 208, 481 and 147 initiated with InSTI, NNRTI and bPI, respectively. For CD4+, %CD4+ and CD4+/CD8+ two main slopes were identified: from month 0 to month 6, with the highest increments; and from month 6 to month 24, with smaller increases every semester. Although the patients on InSTI achieved undetectable viral load faster, for CD4+ and %CD4+ there were no differences in the slopes of change according to the third drug either for the first phase (P=0.137 and P=0.393, respectively) or from month 6 onwards (P=0.834 and P=0.159, respectively). The increase in CD4+/CD8+ was slightly higher for bPI compared with InSTI (difference of 0.0119, 95% CI 0.0020-0.0205; P=0.018), but clinically negligible. From month 6 onwards, no differences were found between treatment groups (P=0.176). Immune restoration measured as CD4+ count, %CD4+ and CD4+/CD8+ increases was independent of the third antiretroviral drug class used when given with two NRTIs.

Hit identification and drug repositioning of potential non-nucleoside reverse transcriptase inhibitors by structure-based approach using computational tools (part II)

AIDS is a global infection involving several complications and its increasing prevalence every year has prioritized our study. Therapy associated with HIV has led to emergence of multidrug resistance and toxicity. Thus, the development of a potent, affordable and safe anti-HIV drug is a global concern. Among the different targets developed, inhibition of non-nucleoside reverse transcriptase (NNRT) is found to be effective and promising. Etravirine, efavirenz, nevirapine, rilpivirine and delavirdine are the marketed NNRTIs available. This study is focused on computational prediction of hit molecules as well as repurposing of various FDA-approved drugs as potential NNRTIs. A synthetic database from ZINCpharmer, publicly available natural databases of coumarins, chromones and chalcones, and two databases of FDA-approved drugs for repurposing were screened to check for the possibility of these compounds to possess anti-HIV activity. Study utilizes a structure-based approach with the generated pharmacophore of target protein (PDB ID: 3MEC), screening of selected datasets is carried out using the Phase tool of Schrodinger. The top filtered compounds with good fitness score were proceeded to molecular docking studies to study their binding affinity to the target. Energy-based calculations using Prime MM-GBSA of Schrodinger was performed to determine free binding energy of the complexes. Prediction of pharmacokinetic parameters of top compounds is further carried out and reported. All the results obtained from different databases are compiled, interpreted and five molecules were subjected to molecular dynamic studies to further confirm the prediction and identified hit molecules for in vitro screening as potential NNRTIs.Communicated by Ramaswamy H. Sarma

A viral genome wide association study and genotypic resistance testing in patients failing first line antiretroviral therapy in the first large countrywide Ethiopian HIV cohort

BackgroundAntiretroviral therapy (ART) was rolled-out in Ethiopia in 2005, but there are no reports on outcome of ART and human immunodeficiency virus drug resistance (HIVDR) at national level. We described acquired drug resistance mutations in pol gene and performed a viral genome wide association study in virologic treatment failure patients who started first line ART during 2009–2011 in the first large countrywide HIV cohort in Ethiopia.MethodsThe outcome of tenofovir (TDF)- and zidovudine (ZDV)-based ART was defined in 874 ART naïve patients using the on-treatment (OT) and intention-to-treat (ITT) analyses. Genotypic resistance testing was done in patients failing ART (> 1000 copies/ml) at month 6 and 12. Near full-length genome sequencing (NFLG) was used to assess amino acid changes in HIV-1 gag, pol, vif, vpr, tat, vpu, and nef genes between paired baseline and month 6 samples.ResultsHigh failure rates were found in ITT analysis at month 6 and 12 (23.3%; 33.9% respectively). Major nucleoside and non-nucleoside reverse transcriptase (NRTI/NNRTI) drug resistance mutations were detected in most failure patients at month 6 (36/47; 77%) and month 12 (20/30; 67%). A high rate of K65R was identified only in TDF treated patients (35.7%; 50.0%, respectively). No significant difference was found in failure rate or extent of HIVDR between TDF- and ZDV- treated patients. All target regions of interest for HIVDR were described by NFLG in 16 patients tested before initiation of ART and at month 6.ConclusionIn this first Ethiopian national cohort, a high degree of HIVDR was seen among ART failure patients, independent on whether TDF- or ZDV was given. However, the major reason to ART failure was lost-to-follow-up rather than virologic failure. Our NFLG assay covered all relevant target genes for antiretrovirals and is an attractive alternative for HIVDR surveillance.

NNRTI-induced HIV-1 protease-mediated cytotoxicity induces rapid death of CD4 T cells during productive infection and latency reversal

BackgroundCurrent efforts towards HIV-1 eradication focus on the reactivation and elimination of the latent viral reservoir, so-called shock and kill therapy. However, work from several groups indicates that infected cell death following virus reactivation is not guaranteed. Thus, it is imperative to develop strategies to foster specific elimination of cells carrying integrated proviruses. It has been shown that some non-nucleoside reverse transcriptase inhibitors (NNRTIs) including efavirenz can induce premature HIV-1 GagPol dimerization in productively infected cells, resulting in intracellular HIV-1 Protease (PR) activation and a reduction in HIV-1 expressing cells.ResultsHere, we document that NNRTI-induced PR activation triggers apoptotic death of productively infected resting or activated T cells in as little as 2 h via caspase-dependent and independent pathways. Rilpivirine, efavirenz and etravirine were the most potent NNRTIs, whereas nevirapine had almost no effect. NNRTI-induced cell killing was prevented by inhibitors of HIV-1 Protease (PR) activity including indinavir and nelfinavir. HIV-1 transmitter founder viruses induced cell killing similarly to lab-adapted HIV-1 except when NNRTI resistance conferring mutations were present in reverse transcriptase. Mutations in PR that confer PR inhibitor (PI) resistance restore NNRTI-induced killing in the presence of PI. Finally, we show that NNRTIs can rapidly eliminate cells in which latent viruses are stimulated to active expression.ConclusionsThis work supports the notion that select NNRTIs might help promote the elimination of HIV-1 producing cells as an adjuvant during shock and kill therapy.

Design of metronidazole derivatives and flavonoids as potential non-nucleoside reverse transcriptase inhibitors using combined ligand- and structure-based approaches

Acquired Immuno Defficiency Syndrome (AIDS) is one of the major global life threatening condition caused by Human Immunodeficiency Virus (HIV) and its prevalence has been increasing every year. Hence, this study has put its emphasis on HIV. Inhibition of Non-Nucleoside Reverse Transcriptase (NNRT) is considered as a well-developed target for HIV. Structure-based pharmacophore model was generated using the Phase tool of Schrodinger and screened database of metronidazole derivatives, flavonoids and metronidazole-flavonoid hybrid molecules. Compounds having good fitness score with similar pharmacophoric features as that of the Non-Nucleoside Reverse Transcriptase Inhibitors (NNRTIs) in market or clinical trials and metronidazole derivatives with reported anti-HIV activity are taken for molecular docking and rescoring by Glide and Prime tools. Hybrid molecules demonstrated good docking score and similar binding interactions as that of reference drugs. From Prime MM-GBSA rescoring, free binding energy was found less and protein–ligand complexes were stabilized with van der Waals free energy and nonpolar solvation terms. Further, atom-based QSAR model of reported metronidazole derivatives as NNRTIs was developed with good statistical values to further refine the database. Pharmacokinetic and toxicity prediction of the top compounds using some free wares like pkCSM and SwissADME reported that identified top compounds have good ADMET profile for oral administration, safe excretion and less toxicity. Study suggests that metronidazole-flavonoid hybrid molecules can be taken as lead molecule for further biological screening and has scope in future drug discovery as safe and potential NNRTIs.Communicated by Ramaswamy H. Sarma