Dolutegravir, the Second-Generation of Integrase Strand Transfer Inhibitors (INSTIs) for the Treatment of HIV

Molecular design and evaluation of aza-polycyclic carbamoyl pyridones as HIV-1 integrase strand transfer inhibitors

Integrase strand transfer inhibitors (INSTIs) are the most prescribed anchor drug in antiretroviral therapy. Today, there is an increasing need for long-acting treatment of HIV-1 infection. Improving drug pharmacokinetics and anti-HIV-1 activity are key to developing more robust inhibitors suitable for long-acting formulations, but 2nd-generation INSTIs have chiral centers, making it difficult to conduct further exploration. In this study, we designed aza-tricyclic and aza-bicyclic carbamoyl pyridone scaffolds which are devoid of the problematic hemiaminal stereocenter present in dolutegravir (DTG). This scaffold hopping made it easy to introduce several substituents, and evolving structure-activity studies using these scaffolds resulted in several leads with promising properties.

The safety of a dolutegravir (DTG)-based antiretroviral treatment (ART) regimen for pregnancy and birth outcomes in Ethiopia: evidence from multicenter cohort study

BACKGROUND

A dolutegravir (DTG)-based antiretroviral regimen has been rolled out for pregnant women in low- and middle-income countries since 2020. However, available safety data are limited to a few clinical trials and observational studies. Hence, we present real-world pregnancy and birth outcome safety data from a large sample multicenter cohort study in Ethiopia.

METHODS

A retrospective cohort study was conducted in fourteen hospitals across Ethiopia from 2017 to 2022. HIV-infected pregnant women were followed from the date of prevention of mother-to-child transmission (PMTCT) care enrolment until the infant was 6-8 weeks old. The primary safety outcome was a composite of adverse pregnancy events comprising spontaneous abortion, intrauterine fetal death (IUFD) before onset of labor, preterm birth, and maternal death. Additionally, a composite adverse birth outcome was assessed, comprising intrapartum fetal demise, low birth weight, and neonatal death. Finally, a composite of adverse pregnancy or birth outcome was also investigated. The exposure of interest was the antiretroviral treatment (ART) regimen used during pregnancy for PMTCT of HIV.

RESULTS

During the study period, 2643 women were enrolled in routine PMTCT care. However, 2490 (92.2%) participants were eligible for the study. A total of 136/1724 (7.9%, 95% CI: 6.7-9.3%) women experienced adverse pregnancy outcomes. Fewer women in the DTG-based group (5.4%, 95% CI: 3.7-7.5%) had adverse pregnancy outcomes than in the Efavirenz (EFV)-based group (8.3%, 95% CI: 6.6-10.3%), P = 0.004. After controlling for baseline differences, the DTG group had a 43% lower risk of adverse pregnancy outcomes (adjusted odd ratio (AOR), 0.57; 95% CI, 0.32-0.96%) and a 53% lower risk of preterm birth (AOR, 0.47; 95% CI, 0.22-0.98%) compared to the EFV group. A total of 103/1616 (6.4%, 95% CI: 5.2-7.7%) women had adverse birth outcomes. Although the difference was not statistically significant, fewer women in the DTG group (30/548; 5.5%, 95% CI: 3.7-7.7%) than in the EFV group (57/830; 6.9%, 95% CI: 5.2-8.8%) had adverse birth outcomes.

CONCLUSIONS

In this study, we observed that DTG-based regimens were associated with better pregnancy and birth outcome safety profiles, reaffirming the WHO recommendation. However, a prospective study is recommended to assess uncaptured maternal and perinatal adverse outcomes, such as congenital abnormalities, and infant growth and neurocognitive development.

HIV-1 pretreatment and acquired antiretroviral drug resistance before tenofovir/ /lamivudine /dolutegravir (TLD) roll-out in Mozambique

BACKGROUND

The World Health Organization (WHO) recommends that HIV treatment scale-up is accompanied by a robust assessment of drug resistance emergence and transmission. The WHO HIV Drug Resistance (HIVDR) monitoring and surveillance strategy includes HIVDR testing in adults both initiating and receiving antiretroviral therapy (ART). Due to limited information about HIVDR in Mozambique, we conducted two nationally representative surveys of adults initiating and receiving first-line ART regimes to better inform the HIV program.

METHODS

We carried out a cross-sectional study between March 2017 and December 2019. Adults (older than 15 years) living with HIV (PLHIV) initiating ART or receiving first-line ART for between 9-15 months at 25 health facilities across all eleven provinces in Mozambique were included. Genotypic HIVDR was assessed on dried blood spots (DBS) when viral loads were  ≥ 1000 copies/ml. Genotypic resistance for non-nucleoside reverse transcriptase inhibitors (NNRTIs), nucleoside reverse transcriptase inhibitors (NRTIs), and protease inhibitors (PIs) was determined using the Stanford HIV database algorithm 9.5 and calibrated population resistance tool 8.1.

RESULTS

Of 828 participants -enrolled, viral load (VL) testing was performed on 408 initiators and 409 ART experienced. Unsuppressed VL was found in 68.1% 419 initiators and 18.8% (77/409) of the ART experienced. Of the 278 initiators and 70 ART experienced who underwent sequencing, 51.7% (144/278) and 75.7% (53/70) were sequenced successfully. Among the new initiators, pretreatment drug resistance (PDR) for NNRTI and PI was found in 16.0% (23/144) and 1.4% (2/144) of the participants, respectively. Acquired drug resistance (ADR) was found in 56.5% (30/53) of the ART-experienced participants of whom 24.5% (13/53) were resistant to both NRTI and NNRTI.

CONCLUSION

High rates of PDR and ADR for NNRTI and ADR for NRTI were observed in our study. These findings support the replacement of NNRTIs with dolutegravir (DTG) but high levels of NRTI resistance in highly treatment-experienced individuals still require attention when transitioning to new regimens. Moreover, the study underlines the need for routine VL testing and HIVDR surveillance to improve treatment management strategies.

A review of dolutegravir-associated weight gain and secondary metabolic comorbidities

Dolutegravir is an integrase inhibitor and is recommended by the World Health Organization as the preferred first-line and second-line human immunodeficiency virus treatment in all populations. Excessive weight gain associated with dolutegravir-based regimens is an emerging issue; however, the long-term metabolic consequences of this effect have not been fully understood. Growing evidence shows that this leads to a higher incidence of hyperglycemia, hypertension, and metabolic syndrome, along with elevated cardiovascular risk. Dolutegravir-based regimens, also associated with greater adipocyte differentiation and greater expression of markers associated with lipid storage, continue to be a problem among patients living with human immunodeficiency virus. The mechanisms by which certain antiretroviral therapy agents differentially contribute to weight gain remain unknown. Some clinical investigators speculate that dolutegravir could interfere with central nervous system appetite regulation (melanocortin-4 receptor) and insulin signaling, or may have better penetration of adipose tissue where they could exert a direct impact on adipose tissue adipogenesis, fibrosis, and insulin resistance. This review summarizes our current understanding of weight gain and fat changes associated with dolutegravir and its possible secondary metabolic comorbidities.

Efficacy, safety, and tolerability of dolutegravir-based ART regimen in Durban, South Africa: a cohort study

BACKGROUND

Dolutegravir is an integrase strand transfer inhibitor that has been recommended for use in first-line antiretroviral regimens by the World Health Organisation and is currently being rolled out globally. There has been safety concerns with dolutegravir which has caused concern about its use in the general population. Dolutegravir first-line regimens have been used in South Africa since early 2020. Therefore, the aim of the present study was to assess the efficacy, safety, and tolerability of first-line dolutegravir-based antiretrovirals amongst adults living with HIV in Durban, South Africa.

METHODS

This was a mixed-methods study, which comprised a cross-sectional survey and longitudinal retrospective follow-up of medical records. The study was conducted between October 2020 and January 2022. Data were described using descriptive and summary statistics. Bivariate logistic regression was applied to socio-demographic and clinical variables and crude odds ratios with a 95% confidence interval was calculated. Pearson chi-square tests, paired sample T-tests, and cross-tabulations were performed on selected variables.

RESULTS

A total of 461 participants were enrolled in the study. There was a significant change in immunological outcomes (p < 0.001) after dolutegravir initiation. Furthermore, an assessment of laboratory parameters showed that there was a significant decrease in cholesterol (p < 0.001) and increase in creatinine (p < 0.001) levels. Increased weight was shown by 60.7% of the participants but was not associated with age, gender, CD4 counts, and previous antiretroviral usage. The study found that 43.6% of the participants experienced at least one side-effect. A total of 21.6% and 23.2% of the participants experienced neuropsychiatric and central nervous system side-effects, respectively. In the bivariate analyses, only gender was shown to be associated with side-effects, and only 1.7% of the participants discontinued the study due to side-effects.

CONCLUSION

Our results suggest that dolutegravir is effective, safe, and well tolerated in the study population.

Design, synthesis and biological evaluation of indole-2-carboxylic acid derivatives as novel HIV-1 integrase strand transfer inhibitors

Integrase plays an important role in the life cycle of HIV-1, and integrase strand transfer inhibitors (INSTIs) can effectively impair the viral replication. However, drug resistance mutations have been confirmed to decrease the efficacy of INSTI during the antiviral therapy. Herein, indole-2-carboxylic acid (1) was found to inhibit the strand transfer of integrase, and the indole nucleus of compound 1 was observed to chelate with two Mg2+ ions within the active site of integrase. Through optimization of compound 1, a series of indole-2-carboxylic acid derivatives were designed and synthesized, and compound 17a was proved to markedly inhibit the effect of integrase, with IC50 value of 3.11 μM. Binding mode analysis of 17a demonstrated that the introduced C6 halogenated benzene ring could effectively bind with the viral DNA (dC20) through π-π stacking interaction. These results indicated that indole-2-carboxylic acid is a promising scaffold for the development of integrase inhibitors.

The Discovery of Indole-2-carboxylic Acid Derivatives as Novel HIV-1 Integrase Strand Transfer Inhibitors

As an important antiviral target, HIV-1 integrase plays a key role in the viral life cycle, and five integrase strand transfer inhibitors (INSTIs) have been approved for the treatment of HIV-1 infections so far. However, similar to other clinically used antiviral drugs, resistance-causing mutations have appeared, which have impaired the efficacy of INSTIs. In the current study, to identify novel integrase inhibitors, a set of molecular docking-based virtual screenings were performed, and indole-2-carboxylic acid was developed as a potent INSTI scaffold. Indole-2-carboxylic acid derivative 3 was proved to effectively inhibit the strand transfer of HIV-1 integrase, and binding conformation analysis showed that the indole core and C2 carboxyl group obviously chelated the two Mg2+ ions within the active site of integrase. Further structural optimizations on compound 3 provided the derivative 20a, which markedly increased the integrase inhibitory effect, with an IC50 value of 0.13 μM. Binding mode analysis revealed that the introduction of a long branch on C3 of the indole core improved the interaction with the hydrophobic cavity near the active site of integrase, indicating that indole-2-carboxylic acid is a promising scaffold for the development of integrase inhibitors.

Absence of Proviral Human Immunodeficiency Virus (HIV) Type 1 Evolution in Early-Treated Individuals With HIV Switching to Dolutegravir Monotherapy During 48 Weeks

Human immunodeficiency virus type 1 (HIV-1) infection is treated with antiretroviral therapy (ART), usually consisting of 2-3 different drugs, referred to as combination ART (cART). Our recent randomized clinical trial comparing a switch to dolutegravir monotherapy with continuation of cART in early-treated individuals demonstrated sustained virological suppression over 48 weeks. Here, we characterize the longitudinal landscape of the HIV-1 reservoir in these participants, with particular attention to potential differences between treatment groups regarding evidence of evolution as a proxy for low-level replication. Near full-length HIV-1 proviral polymerase chain reaction and next-generation sequencing was applied to longitudinal peripheral blood mononuclear cell samples to assess proviral evolution and the potential emergence of drug resistance mutations (DRMs). Neither an increase in genetic distance nor diversity over time was detected in participants of both treatment groups. Single proviral analysis showed high proportions of defective proviruses and low DRM numbers. No evidence for evolution during dolutegravir monotherapy was found in these early-treated individuals.

Central nervous system disorders after use of dolutegravir: evidence from preclinical and clinical studies

The evaluation of dolutegravir based on available preclinical and clinical studies reveals a risk of central nervous system (CNS) disorders associated with long-term use of the drug. The available literature on the pharmacokinetics of the drug, including its penetration of the blood-brain barrier, was reviewed, as well as clinical trials assessing the incidence of adverse effects in the CNS and the frequency of its discontinuation. This paper also summarizes the impact of factors affecting the occurrence of CNS disorders and indicates the key role of pharmacovigilance in the process of supplementing knowledge on the safety of drugs, especially those that are newly registered.

Fluorine in anti-HIV drugs approved by FDA from 1981 to 2023

Human immunodeficiency virus (HIV) is the etiological agent of acquired immunodeficiency syndrome (AIDS). Nowadays, FDA has approved over thirty antiretroviral drugs grouped in six categories. Interestingly, one-third of these drugs contain different number of fluorine atoms. The introduction of fluorine to obtain drug-like compounds is a well-accepted strategy in medicinal chemistry. In this review, we summarized 11 fluorine-containing anti-HIV drugs, focusing on their efficacy, resistance, safety, and specific roles of fluorine in the development of each drug. These examples may be of help for the discovery of new drug candidates bearing fluorine in their structures.

Prevalence of Cardiometabolic Disease Risk Factors in People With HIV Initiating Antiretroviral Therapy at a High-Volume HIV Clinic in Kampala, Uganda

Background

Cardiometabolic diseases are a leading cause of HIV-related morbidity and mortality, yet routine screening is not undertaken in high-burden countries. We aimed to assess the prevalence and risk factors of the metabolic syndrome (MetS) and its components in adult Ugandan people with HIV (PWH) initiating dolutegravir-based antiretroviral therapy (ART).

Methods

We conducted a cross-sectional study using baseline sociodemographic and clinical data of PWH aged ≥18 years enrolled in the Glucose metabolism changes in Ugandan HIV patients on Dolutegravir (GLUMED) study from January to October 2021. MetS was defined as having ≥3 of the following: abdominal obesity, hypertension (HTN), hyperglycemia, elevated triglycerides, and low high-density lipoprotein cholesterol. Multiple logistic regression was used to assess associations between potential risk factors and MetS and its components.

Results

Three hundred nine PWH were analyzed (100% ART-naïve, 59.2% female, median age 31 years, and median CD4 count 318 cells/mm3). The prevalence of MetS was 13.9%. The most common cardiometabolic condition was dyslipidemia (93.6%), followed by abdominal obesity (34.0%), hyperglycemia (18.4%), and HTN (8.1%). In adjusted analysis, MetS was associated with age >40 years (adjusted odds ratio [aOR], 3.33; 95% CI, 1.45-7.67) and CD4 count >200 cells/mm3 (aOR, 3.79; 95% CI, 1.23-11.63). HTN was associated with age >40 years (aOR, 2.96; 95% CI, 1.32-6.64), and dyslipidemia was associated with urban residence (aOR, 4.99; 95% CI, 1.35-18.53).

Conclusions

Cardiometabolic risk factors were common in this young Ugandan cohort of PWH initiating dolutegravir-based ART, underscoring the need for programmatic implementation of surveillance and management of comorbidities in Uganda and similar settings.

Repurposing of FDA-approved drugs as dual-acting MAO-B and AChE inhibitors against Alzheimer's disease: An in silico and in vitro study

An in silico consensus molecular docking approach and in vitro evaluations were adopted in the present study to explore a dataset of FDA-approved drugs as novel multitarget MAO-B/AChE agents in the treatment of Alzheimer's disease (AD). GOLD 5.3 and Glide were employed in the virtual assessments and consensus superimpositions of the obtained poses were applied to increase the reliability of the docking protocols. Furthermore, the top ranked molecules were subjected to binding free energy calculations using MM/GBSA, Induced fit docking (IFD) simulations, and a literature review. Consequently, the top four multitarget drugs were examined for their in vitro MAO-B and AChE inhibition effects. The consensus molecular docking identified Dolutegravir, Rebamipide, Loracarbef and Diflunisal as potential multitarget drugs. The biological data demonstrated that most of the docking scores were in good correlation with the in vitro experiments, however the theoretical simulations in the active site of MAO-B identified two false-positives - Rebamipide and Diflunisal. Dolutegravir and Loracarbef were accessed as active MAO-B inhibitors, while Dolutegravir, Rebamapide and Diflunisal as potential AChE inhibitors. The antiretroviral agent Dolutegravir exhibited the most potent multitarget activity - 41% inhibition of MAO-B (1 μM) and 68% inhibition of AChE (10 μM). Visualizations of the intermolecular interactions of Dolutegravir in the active sites of MAO-B and AChE revealed the formation of several stable hydrogen bonds. Overall, Dolutegravir was identified as a potential anti-AD drug, however further in vivo evaluations should be considered.

Comparative Safety and Changes in Immunologic and Virologic Parameters of Dolutegravir versus Efavirenz-Based Antiretroviral Therapies Among HIV Patients: A Retrospective Cohort Study

Background

In combination with other two antiretroviral drugs, an efavirenz (EFV) or dolutegravir (DTG)-based regimen is the treatment of choice for human immunodeficiency virus (HIV) infection. This study aimed to determine the safety and changes in immunologic and virologic parameters of DTG compared with EFV-based ART as first-line HIV treatment among HIV patients.

Methods

A retrospective hospital-based cohort study was carried out from September 1, 2019 to August 30, 2020 at HIV clinics of three selected hospitals in North-West-East Ethiopia, Amhara Region. All HIV patients ≥3 years old, who had been on either DTG or EFV-based combination anti-retroviral therapy (cART), and had detectable viral load (VL) were included. Descriptive and multivariate Cox regression analyses were used.

Results

Overall, 990 HIV patients were included in the analysis (DTG n=694, EFV n=296). A VL of <50 copies/mL was observed in 69% of patients in the DTG group and 66% in the EFV group (crude hazard ratio [CHR] =1.28, 95% CI: 1.08-1.51; p=0.004). Out of the total, 289 (42%) of the patients in the DTG group reported adverse drug events (ADEs) compared with 147 (50%) in the EFV group (p=0.020). Younger age, opportunistic infections (OIs), bed-ridden condition, no prophylaxis for OIs, low baseline cluster of differentiation 4 (CD4) count, high baseline VL, poor adherence, and ADEs were predictors of poor survival, and younger age, OIs, low baseline CD4, DTG-based initial regimen, poor adherence with cART, naïve treatment history, and student job type were predictors of poor safety outcomes.

Conclusion

The DTG-based regimen demonstrates an improved viral suppression and CD4 cell recovery, and better safety profile compared with the EFV-based regimen for the treatment of HIV-infected patients. A baseline CD4⁺ T-cell count <200 cells/mm³, OIs, and poor adherence with therapy were factors associated with poor survival and safety outcomes. HIV patients with these risk factors should be treated and monitored regularly.

Evaluation of Circulating and Archived HIV-1 Integrase Drug-Resistance Variants among Patients on Third-Line ART in Cameroon: Implications for Dolutegravir-Containing Regimens in Resource-Limited Settings

To ensure the long-term efficacy of dolutegravir (DTG), we evaluated the genotypic profile in viral reservoirs among patients on third-line (3L) antiretroviral therapy (ART) in Cameroon, according to prior exposure to raltegravir (RAL). A facility-based study was conducted from May through December 2021 among patients on 3L ART from HIV treatment centers in Yaoundé and Douala. Viral load was measured, and genotyping was performed on plasma RNA and proviral DNA. HIV-1 drug resistance mutations were interpreted using HIVdb.v9.1 and phylogeny analysis was performed using MEGA.v7, with P < 0.05 considered significant. Of the 12,093 patients on ART, 53 fully met our inclusion criteria. The median (IQR) age was 51 years (40 to 55 years), and the male/female ratio was 4/5. The median duration on integrase strand-transfer inhibitors (INSTI)-containing regimens was 18 months (12 to 32 months), and 15.09% (8/53) were exposed to RAL. The most administered 3L ART was TDF+3TC+DTG+DRV/r (33.96%, 18/53). Only 5.66% (3/53) had unsuppressed viremia (>1000 copies/mL). Resistance testing in proviral DNA was successful for 18/22 participants and revealed 1/18 patients (5.56%, in the RAL-arm) with archived mutations at major resistance positions (G140R and G163R). Five subtypes were identified, CRF02_AG (12/18), CRF22_01AE (3/18), A1 (1/18), G (1/18), and F2 (1/18). In Cameroon, 3L-experienced patients had a good virological response with a low level of archived mutations in the integrase. This finding underscored the use of DTG-containing ART for heavily treated patients in similar programmatic settings. However, patients with prior exposure to RAL should be closely monitored following a stratified or personalized approach to mitigate risks of INSTI-resistance, alongside pharmacovigilance. IMPORTANCE We described the analysis of the genotypes of the population within third-line antiviral therapy in Cameroon, with a focus on defining the effects of prior raltegravir (RAL) treatment and resistance mutations for current dolutegravir (DTG) treatment. While supporting the current transition to DTG-containing ART in resource-limited settings toward the achievement of the UNAIDS' goal of HIV elimination by 2030, our findings suggested that RAL-exposed patients may need a specific monitoring approach either in a stratified or personalized model of third-line ART to ensure the long-term success of DTG-containing regimens.

Dolutegravir-Based Regimen Ensures High Virological Success despite Prior Exposure to Efavirenz-Based First-LINE ART in Cameroon: An Evidence of a Successful Transition Model

To ensure optimal prescribing practices in the dolutegravir-era in Cameroon, we compared first-line virological response (VR) under tenofovir + lamivudine + dolutegravir (TLD) according to prior exposure to tenofovir + lamivudine + efavirenz (TLE). A facility-based survey was conducted among patients initiating antiretroviral therapy (ART) with TLD (I-TLD) versus those transitioning from TLE to TLD (T-TLD). HIV viral load was performed and unsuppressed participants (VL > 1000 copies/mL) had genotyping performed by Sanger sequencing. Of the 12,093 patients followed, 310 (mean-age: 41 ± 11 years; 52.26% female) complied with study criteria (171 I-TLD vs. 139 T-TLD). The median ART-duration was 14 (12−17) months among I-TLDs versus 28 (24.5−31) months among T-TLDs (15 (11−19) on TLE and 14 (9−15) on TLD), and 83.15% (148/178) were at WHO clinical stages I/II. The viral suppression rate (<1000 copies/mL) was 96.45%, with 97.08% among I-TLDs versus 95.68% among T-TLDs (p = 0.55). VR was similar in I-TLD versus T-TLD at <400 copies/mL (94.15% versus 94.42%) and age, gender, residence, ART-duration, and WHO stages were not associated with VR (p > 0.05). Genotyping was successful for 72.7% (8/11), with no major mutations to integrase inhibitors found. VR is optimal under first-line TLD after 14 months, even among TLE-exposed, thus confirming the effectiveness of transitioning from TLE to TLD in similar settings, supported by strong pharmacological potency and genetic barrier of dolutegravir.

Different Pathways Conferring Integrase Strand-Transfer Inhibitors Resistance

Integrase Strand Transfer Inhibitors (INSTIs) are currently used as the most effective therapy in the treatment of human immunodeficiency virus (HIV) infections. Raltegravir (RAL) and Elvitegravir (EVG), the first generation of INSTIs used successfully in clinical treatment, are susceptible to the emergence of viral resistance and have a high rate of cross-resistance. To counteract these resistant mutants, second-generation INSTI drugs have been developed: Dolutegravir (DTG), Cabotegravir (CAB), and Bictegravir (BIC). However, HIV is also able to develop resistance mechanisms against the second-generation of INSTIs. This review describes the mode of action of INSTIs and then summarizes and evaluates some typical resistance mutations, such as substitution and insertion mutations. The role of unintegrated viral DNA is also discussed as a new pathway involved in conferring resistance to INSTIs. This allows us to have a more detailed understanding of HIV resistance to these inhibitors, which may contribute to the development of new INSTIs in the future.

Primary resistance against integrase strand transfer inhibitors in integrase strand transfer inhibitor-naive patients failing first- and second-line ART in Tanzania

INTRODUCTION

Sub-Saharan African countries are introducing integrase strand transfer inhibitors (INSTIs) in their ART programmes as the preferred first-line regimen, and dolutegravir is the INSTI of choice due to its potency, tolerability and high genetic barrier to resistance. Dolutegravir was introduced into the first-line ART regimen in Tanzania in 2019. However, there is a paucity of data on the occurrence of mutations in HIV lineages circulating in Tanzania. This study aimed to determine the prevalence of INSTI primary resistance mutations in Tanzanian patients exposed to ART but not INSTIs.

METHODS

Plasma samples from 50 INSTI-naive patients failing first- or second-line ART [median (IQR) age: 40 (21.93-46.41) years; 68% women] were subjected to Sanger sequencing of the HIV integrase gene. Participants had been on ART for a median (IQR) duration of 7.32 (4.73-9.29) years, with 80% and 20% failing first- and second-line ART, respectively.

RESULTS

No major INSTI mutations were found, but 2 (4%) participants had the accessory mutation T97A. Using the REGA HIV-1 subtyping tool, HIV subtype A1 (53.1%) was found to be dominant, followed by subtypes C (30.6%) and D (16.3%).

CONCLUSIONS

This study found no current evidence for transmitted resistance against INSTIs among unexposed patients failing ART and supports the scale-up of INSTI-based regimens. However, the presence of accessory mutations calls for the surveillance of INSTI resistance mutations to ensure that the anticipated long-term desired outcomes are achieved.

Effect of Dolutegravir on Plasma Glucose Among Human Immunodeficiency Virus Patients in a Community Health Center Setting

Background Dolutegravir has become one of the initial backbones in antiretroviral therapy regimens for most patients with HIV in several recent clinical guidelines. However, dolutegravir has been associated with severe cases of hyperglycemia and the new-onset of diabetes in multiple case reports and clinical trials. A community health center noticed an increasing number of new-onset hyperglycemia incidences in patients on dolutegravir. Method Retrospective chart review of patients who started on dolutegravir or dolutegravir combination regimen (Triumreq®, Juluca®, GlaxoSmithKline (GSK), Research Triangle Park, NC) between the dates of January 1st, 2013 and January 1st, 2018 who have been treated in community healthcare centers. Baseline blood sugar and/or hemoglobin A1C before starting dolutegravir, at three to six months of treatment, and at the end of the study were compared between subjects. Four hundred twenty-two subjects were enrolled. Results Dolutegravir had little effect on plasma glucose among 72% of the subjects (n=305). However, 7% of the subjects (n=28) on dolutegravir treatment with no glucose intolerance met the criteria for prediabetes at three to six months of therapy. One of the subjects had developed diabetes three to six months after dolutegravir was initiated. In addition, at the end of the study, 13% of patients developed prediabetes (n=56) and 1.4% developed diabetes (n=6). Among the 24 subjects that had diabetes before dolutegravir was initiated, 83% required intensification of their diabetes regimen. Conclusion Dolutegravir may cause a moderate increase in plasma sugar after three to six months of therapy. Further increases in plasma sugar have been noticed in up to 13% of subjects meeting the criteria for prediabetes. Due to the existence of confounding variables, patients with diabetes should not be switched from dolutegravir.

Pre-Treatment Integrase Inhibitor Resistance and Natural Polymorphisms among HIV-1 Subtype C Infected Patients in Ethiopia

Dolutegravir-based antiretroviral therapy (ART) has been scaled up in many developing countries, including Ethiopia. However, subtype-dependent polymorphic differences might influence the occurrence of HIV-drug-resistance mutations (HIVDRMs). We analyzed the prevalence of pre-treatment integrase strand transfer inhibitor (INSTI) HIVDRMs and naturally occurring polymorphisms (NOPs) of the integrase gene, using plasma samples collected as part of the national HIVDR survey in Ethiopia in 2017. We included a total of 460 HIV-1 integrase gene sequences from INSTI-naïve (n = 373 ART-naïve and n = 87 ART-experienced) patients. No dolutegravir-associated HIVDRMs were detected, regardless of previous exposure to ART. However, we found E92G in one ART-naïve patient specimen and accessory mutations in 20/460 (4.3%) of the specimens. Moreover, among the 288 integrase amino acid positions of the subtype C, 187/288 (64.9%) were conserved (<1.0% variability). Analysis of the genetic barrier showed that the Q148H/K/R dolutegravir resistance pathway was less selected in subtype C. Docking analysis of the dolutegravir showed that protease- and reverse-transcriptase-associated HIVDRMs did not affect the native structure of the HIV-1 integrase. Our results support the implementation of a wide scale-up of dolutegravir-based regimes. However, the detection of polymorphisms contributing to INSTI warrants the continuous surveillance of INSTI resistance.

Fluorine Modifications Contribute to Potent Antiviral Activity against Highly Drug-Resistant HIV-1 and Favorable Blood-Brain Barrier Penetration Property of Novel Central Nervous System-Targeting HIV-1 Protease Inhibitors In Vitro

To date, there are no specific treatment regimens for HIV-1-related central nervous system (CNS) complications, such as HIV-1-associated neurocognitive disorders (HAND). Here, we report that two newly generated CNS-targeting HIV-1 protease (PR) inhibitors (PIs), GRL-08513 and GRL-08613, which have a P1-3,5-bis-fluorophenyl or P1-para-monofluorophenyl ring and P2-tetrahydropyrano-tetrahydrofuran (Tp-THF) with a sulfonamide isostere, are potent against wild-type HIV-1 strains and multiple clinically isolated HIV-1 strains (50% effective concentration [EC50]: 0.0001 to ∼0.0032 μM). As assessed with HIV-1 variants that had been selected in vitro to propagate at a 5 μM concentration of each HIV-1 PI (atazanavir, lopinavir, or amprenavir), GRL-08513 and GRL-08613 efficiently inhibited the replication of these highly PI-resistant variants (EC50: 0.003 to ∼0.006 μM). GRL-08513 and GRL-08613 also maintained their antiviral activities against HIV-2ROD as well as severely multidrug-resistant clinical HIV-1 variants. Additionally, when we assessed with the in vitro blood-brain barrier (BBB) reconstruction system, GRL-08513 and GRL-08613 showed the most promising properties of CNS penetration among the evaluated compounds, including the majority of FDA-approved combination antiretroviral therapy (cART) drugs. In the crystallographic analysis of compound-PR complexes, it was demonstrated that the Tp-THF rings at the P2 moiety of GRL-08513 and GRL-08613 form robust hydrogen bond interactions with the active site of HIV-1 PR. Furthermore, both the P1-3,5-bis-fluorophenyl- and P1-para-monofluorophenyl rings sustain greater contact surfaces and form stronger van der Waals interactions with PR than is the case with darunavir-PR complex. Taken together, these results strongly suggest that GRL-08513 and GRL-08613 have favorable features for patients infected with wild-type/multidrug-resistant HIV-1 strains and might serve as candidates for a preventive and/or therapeutic agent for HAND and other CNS complications.

Antiviral Activity and Resistance Profile of the Novel HIV-1 Non-Catalytic Site Integrase Inhibitor, JTP-0157602

HIV-1 integrase (IN) is an essential enzyme for viral replication. Non-catalytic site integrase inhibitors (NCINIs) are allosteric HIV-1 IN inhibitors and a potential new class of antiretrovirals. In this report, we identified a novel NCINI, JTP-0157602, with an original scaffold. JTP-0157602 exhibited potent antiviral activity against HIV-1 and showed a serum-shifted EC₉₀ of 138 nM, which is comparable to the FDA-approved IN strand transfer inhibitors (INSTIs). This compound was fully potent against a wide range of recombinant viruses with IN polymorphisms, including amino acids 124/125, a hot spot of IN polymorphisms. In addition, JTP-0157602 retained potent antiviral activity against a broad panel of recombinant viruses with INSTI-related resistant mutations, including multiple substitutions that emerged in clinical studies of INSTIs. Resistance selection experiments of JTP-0157602 led to the emergence of A128T and T174I mutations, which are located at the lens epithelium-derived growth factor/p75 binding pocket of IN. JTP-0157602 inhibited HIV-1 replication mainly during the late-phase of the replication cycle, and HIV-1 virions produced by reactivation from HIV-1 latently-infected Jurkat cells in the presence of JTP-0157602 were non-infectious. These results suggest that JTP-0157602 and analog compounds can be used to treat HIV-1 infectious diseases. IMPORTANCE Non-catalytic site integrase inhibitors (NCINIs) are allosteric HIV-1 integrase (IN) inhibitors that bind to the lens epithelium-derived growth factor (LEDGF)/p75 binding pocket of IN. NCINIs are expected to be a new class of anti-HIV-1 agents. In this study, we present a novel NCINI, JTP-0157602, which has potent activity against a broad range of HIV-1 strains with IN polymorphisms. Furthermore, JTP-0157602 shows strong antiviral activity against IN strand transfer inhibitor-resistant mutations, suggesting JTP-0157602 and its analogs are potential agents to treat HIV-1 infections. Structural modeling indicated that JTP-0157602 binds to the LEDGF/p75 binding pocket of IN, and the results of in vitro resistance induction revealed the JTP-0157602-resistance mechanism of HIV-1. These data shed light on developing novel NCINIs, which exhibit potent activity against HIV-1 with broad IN polymorphisms and multi-drug resistant HIV-1 variants.

HIV-1 integrase resistance associated mutations and the use of dolutegravir in Sub-Saharan Africa: A systematic review and meta-analysis

As sub-Saharan Africa (SSA) countries are transitioning to dolutegravir (DTG)-based ART, baseline data are required for optimal monitoring of therapeutic response. In this frame, we sought to generate up-to-date evidence on the use of integrase-strand transfer inhibitors (INSTI) and associated drug resistance mutations (DRMs) within SSA. In this systematic review and meta-analysis, we included randomized and non-randomized trials, cohort-studies, cross-sectional studies, and case-reports published on INSTI or integrase DRMs in SSA. We included studies of patients exposed to DTG, raltegravir (RAL) or elvitegravir (EVG). Primary outcomes were "the rate of virological control (VC:<50copies/ml)" and "the presence of DRMs" on INSTI-based regimens among patients in SSA. We synthesised extracted data using subgroup analysis, and random effect models were used where appropriate. Additional analyses were conducted to assess study heterogeneity. We identified 1,916 articles/citations through database searches, of which 26 were included in the analysis pertaining to 5,444 patients (mean age: 37±13 years), with 67.62% (3681/5444) female. Specifically, 46.15% (12/26) studies focused on DTG, 26.92% (7/26) on RAL, 23.08% (6/26) on both DTG and RAL, and 3.85% (1/26) on EVG. We found an increasing use of DTG overtime (0% before 2018 to 100% in 2021). Median treatment duration under INSTI-based regimens was 12 [9-36] months. Overall, the rate of VC was 88.51% [95%CI: 73.83-97.80] with DTG vs. 82.49% [95%CI: 55.76-99.45] and 96.55% [95%CI: 85.7-100.00] with RAL and EVG, respectively. In univariate analysis, VC with DTG-containing vs. other INSTI-regimens was significantly higher (OR = 1.44 [95%CI: 1.15-1.79], p = 0.0014). Among reported DRMs at failure, the only DTG resistance-mutations were G118R and R263K. In SSA, DTG presents a superiority effect in VC compared to other INSTIs. Nonetheless, the early detection of INSTI-DRMs calls for sentinel surveillance for a successful transition and a sustained efficacy of DTG in SSA. PROSPERO Registration Number: CRD42019122424.

A Critical Review of the Biochemical Mechanisms and Epigenetic Modifications in HIV- and Antiretroviral-Induced Metabolic Syndrome

Metabolic syndrome (MetS) is a non-communicable disease characterised by a cluster of metabolic irregularities. Alarmingly, the prevalence of MetS in people living with Human Immunodeficiency Virus (HIV) and antiretroviral (ARV) usage is increasing rapidly. This study aimed to look at biochemical mechanisms and epigenetic modifications associated with HIV, ARVs, and MetS. More specifically, emphasis was placed on mitochondrial dysfunction, insulin resistance, inflammation, lipodystrophy, and dyslipidaemia. We found that mitochondrial dysfunction was the most common mechanism that induced metabolic complications. Our findings suggest that protease inhibitors (PIs) are more commonly implicated in MetS-related effects than other classes of ARVs. Furthermore, we highlight epigenetic studies linking HIV and ARV usage to MetS and stress the need for more studies, as the current literature remains limited despite the advancement in and popularity of epigenetics.

Baseline integrase drug resistance mutations and conserved regions across HIV-1 clades in Cameroon: implications for transition to dolutegravir in resource-limited settings

BACKGROUND

Transition to dolutegravir-based regimens in resource-limited settings (RLS) requires prior understanding of HIV-1 integrase variants and conserved regions. Therefore, we evaluated integrase drug resistance mutations (DRMs) and conserved regions amongst integrase strand transfer inhibitor (INSTI)-naive patients harbouring diverse HIV-1 clades in Cameroon.

METHODS

A cross-sectional study was conducted amongst 918 INSTI-naive patients from Cameroon (89 ART-naive and 829 ART-experienced patients). HIV-1 sequences were interpreted regarding INSTI-DRMs using the Stanford HIVdb v8.9-1 and the 2019 IAS-USA list. Amino acid positions with <1% variability were considered as highly conserved. Subtyping was performed by phylogeny.

RESULTS

Overall prevalence (95% CI) of INSTI-DRMs was 0.8% (0.4-1.7), with 0.0% (0.0-4.0) amongst ART-naive versus 0.9% (0.5-1.9) amongst ART-experienced patients; P = 0.44. Accessory mutations (95% CI) were found in 33.8% (30.9-37.0), with 38.2% (28.1-49.1) amongst ART-naive versus 33.4% (30.4-36.7) amongst ART-experienced patients; P = 0.21. Of 288 HIV-1 integrase amino acid positions, 58.3% were highly conserved across subtypes in the following major regions: V75-G82, E85-P90, H114-G118, K127-W132, E138-G149, Q168-L172, T174-V180, W235-A239 and L241-D253. Wide genetic diversity was found (37 clades), including groups M (92.3%), N (1.4%), O (6.2%) and P (0.1%). Amongst group M, CRF02_AG was predominant (47.4%), with a significantly higher frequency (95% CI) of accessory mutations compared with non-AG [41.4% (36.8-46.0) versus 27.1% (23.3-31.2) respectively; P < 0.001].

CONCLUSIONS

The low baseline of INSTI-DRMs (<1%) in Cameroon suggests effectiveness of dolutegravir-based regimens. In spite of high conservation across clades, the variability of accessory mutations between major circulating strains underscores the need for monitoring the selection of INSTI-DRMs while scaling up dolutegravir-based regimens in RLS.

Metabolic Changes Associated With the Use of Integrase Strand Transfer Inhibitors Among Virally Controlled Women

BACKGROUND

Integrase strand transfer inhibitors (INSTIs) have been associated with weight gain among women living with HIV. We aimed to investigate the association between INSTIs and change in cardiometabolic risk indicators.

SETTING

Retrospective cohort.

METHODS

Data from 2006 to 2017 were analyzed from women living with HIV enrolled in the longitudinal Women's Interagency HIV Study who were virally controlled on antiretroviral therapy (ART) for ≥5 consecutive semiannual visits. Women who switched/added an INSTI to ART (INSTI group) were compared with women who remained on non-INSTI ART (non-INSTI group). Outcomes included changes in fasting lipids and glucose, hemoglobin A1c (HbA1c), blood pressure (BP), and incident diabetes, hypertension, and insulin resistance. Outcomes were measured 6-12 months before and 6-18 months after INSTI switch/add in the INSTI group with comparable visits in the non-INSTI group. Longitudinal linear regression models compared change over time in each outcome by the study group.

RESULTS

One thousand one hundred eighteen participants (234 INSTI, 884 non-INSTI) were followed for a median 2.0 (Q1 1.9, Q3 2.0) years. Participants were median age 49 years, 61% Black, and 73% overweight or obese (body mass index ≥25 kg/m). Compared with non-INSTI, the INSTI group experienced greater increases in HbA1c (+0.05 vs. -0.06 mg/dL, P = 0.0318), systolic BP (+3.84 vs. +0.84 mm Hg, P = 0.0191), and diastolic BP (+1.62 vs. -0.14 mm Hg, P = 0.0121), with greatest change in HbA1c among women on INSTIs with ≥5% weight gain.

CONCLUSIONS

INSTI use was associated with unfavorable changes in HbA1c and systolic and diastolic BP during short-term follow-up. Further research is needed to understand long-term cardiometabolic effects of INSTI use.

Near point-of-care, point-mutation test to detect drug resistance in HIV-1: a validation study in a Mexican cohort

OBJECTIVE

Pretreatment HIV-drug resistance (PDR, HIVDR) to non-nucleoside reverse transcriptase inhibitors (NNRTIs) is increasing globally. NNRTIs continue to be used as first-line antiretroviral therapy (ART) in some communities due to the cost of dolutegravir-based ART or dolutegravir-associated adverse events. A simplified version of the oligonucleotide ligation assay (OLA) - 'OLA-Simple' - is a low-cost, near point-of-care assay that provides ready-to-use lyophilized reagents and reports HIVDR mutations as colored lines on lateral flow strips. Our objective was to design and validate OLA-Simple for a Mexican cohort.

DESIGN

OLA-Simple probes to detect K65R, K103N/S, Y181C, M184V, and G190A were optimized for HIV Mexican sequences. Sixty clinical plasma specimens were analyzed by OLA-Simple by technicians blinded to Illumina-MiSeq sequences, and HIVDR results were compared.

METHODS

Plasma RNA was tested using OLA-Simple kits. OLA-Simple lateral flow strips were read by in-house software, and were classified as mutant or wild-type at each codon. The comparison of results by OLA-Simple and Miseq was used to generate receiver-operating characteristic curves.

RESULTS

OLA-Simple PCR amplified 59 of 60 specimens and successfully genotyped 287 of 295 codons, with eight of 295 (2.7%) indeterminate results. Compared to MiSeq, OLA-Simple gave five of 295 (1.7%) false-positive and four of 295 (1.4%) false-negative results. Excluding indeterminate results, OLA-Simple classified mutant with an accuracy of 97.4 and 98.8% when using thresholds at 10 and 25% mutant within an individual's HIV quasispecies, respectively.

CONCLUSIONS

Compared to MiSeq, OLA-Simple detected HIVDR with high sensitivity and accuracy. OLA-Simple could expand access to affordable and rapid HIVDR testing to guide appropriate ART choices in populations using NNRTI-based ART.

Pretreatment resistance mutations and treatment outcomes in adults living with HIV-1: a cohort study in urban Malawi

Background

Pre-treatment drug resistance (PDR) among antiretroviral drug-naïve people living with HIV (PLHIV) represents an important indicator for the risk of treatment failure and the spread of drug resistant HIV variants. We assessed the prevalence of PDR and treatment outcomes among adults living with HIV-1 in Lilongwe, Malawi.

Methods

We selected 200 participants at random from the Lighthouse Tenofovir Cohort Study (LighTen). Serum samples were drawn prior to treatment initiation in 2014 and 2015, frozen, and later analyzed for the presence of HIV-1 drug resistance mutations. Amplicons were sequenced and interpreted by Stanford HIVdb interpretation algorithm 8.4. We assessed treatment outcomes by evaluating clinical outcome and viral suppression at the end of the follow-up period in October 2019.

Results

PDR testing was successful in 197 of 200 samples. The overall NNRTI- PDR prevalence was 13.7% (27/197). The prevalence of intermediate or high level NNRTI- PDR was 11.2% (22/197). The most common mutation was K103N (5.6%, 11/197), followed by Y181C (3.6%, 7/197). In one case, we detected an NRTI resistance mutation (M184V), in combination with multiple NNRTI resistance mutations. All HIV-1 isolates analyzed were of subtype C. Of the 27 patients with NNRTI- PDR, 9 were still alive, on ART, and virally suppressed at the end of follow-up.

Conclusion

The prevalence of NNRTI- PDR was above the critical level of 10% suggested by the Global Action Plan on HIV Drug Resistance. The distribution of drug resistance mutations was similar to that seen in previous studies from the region, and further supports the introduction of integrase inhibitors in first-line treatment in Malawi. Furthermore, our findings underline the need for continued PDR surveillance and pharmacovigilance in Sub-Saharan Africa.

HIV-1 integrase resistance associated mutations and the use of dolutegravir in Sub-Saharan Africa: a systematic review and meta-analysis protocol

BACKGROUND

Sub-Saharan Africa carries the greatest burden of HIV-infection with increasing drug resistance burden, which requires improved patient management and monitoring. Current WHO recommendations suggest transitioning to dolutegravir-based (adults) or raltegravir-based-regimens (neonates) for initial antiretroviral therapy (ART) and as a suitable alternative in cases of multi-resistance in resource-limited settings. This review aims at synthesizing the current knowledge on dolutegravir use and integrase resistance-associated mutations found before the wide use of dolutegravir-based regimens.

METHODS

This systematic review will include randomized and non-randomized trials, cohort, and cross-sectional studies published on dolutegravir use or integrase resistance-associated mutations in Sub-Saharan Africa. Searches will be conducted (from 2007 onwards) in PubMed, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), Latin American and Caribbean Health Sciences Literature (LILAC), Web of Science, African Journals Online, and Cumulative Index to Nursing and Allied Health Literature (CINAHL) databases. Hand searching of the reference lists of relevant reviews and trials will be conducted and we will also look for conference abstracts. We will include studies of adults and/or children exposed to integrase inhibitors-based therapies; especially dolutegravir or raltegravir (which is our intervention of interest as compared to other antiretroviral regimens). We will exclude studies of patients with specific co-morbidities such as tuberculosis or opportunistic infections. Primary outcomes will be "the rate of viral suppression" and "the level of drug resistance" on integrase inhibitor-based regimens among patients in Sub-Saharan Africa. Secondary outcomes will be "the effect of baseline viremia on viral suppression," "the effect of treatment duration on viral suppression," "the proportion of patients with immune recovery," "the rate of non-adherence," "rate of adverse events;" "drug resistance according to different integrase inhibitor-based regimens," and "drug resistance according to viral subtypes/recombinants." Two reviewers will independently screen titles and abstracts, assess the full texts for eligibility, and extract data. If data permits, random effects models will be used where appropriate. Subgroup and additional analyses will be conducted to explore the potential sources of heterogeneity (e.g., age, sex, baseline viremia, CD4 following treatment, treatment duration, and adherence level).

DISCUSSION

This review will help to strengthen evidence on the effectiveness of integrase strand transfer inhibitors by contributing to current knowledge on the use of dolutegravir and/or raltegravir (especially for neonates) in Sub-Saharan Africa. Results will therefore help in setting-up baseline data for an optimal management of people living with HIV as Sub-Saharan African countries are transitioning to dolutegravir-based regimens. Evidence will also support HIV/AIDS programs in identifying gaps and actions to be undertaken for improved long-term care and treatment of people living with HIV in Sub-Saharan Africa.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42019122424.

Dolutegravir Population Pharmacokinetics in a Real-Life Cohort of People Living With HIV Infection: A Covariate Analysis

BACKGROUND

There are growing concerns about dolutegravir (DTG)-related neuropsychiatric adverse events and about differences in the characteristics of people living with HIV infection (PLWH) potentially associated with higher risks of said side effects. Several studies have shown that DTG was stopped more frequently among women, older PLWH, and PLWH who initiated abacavir (ABC) at the same time. This study aimed to clarify the factors affecting the pharmacokinetics (PKs) of DTG in a real-life cohort of PLWH using a population PK approach.

METHODS

The model-building strategy was based on a previously published model developed from premarketing trials (1-compartment model with first-order absorption and a lag time). Sparse therapeutic drug monitoring data were obtained from a real-life cohort of 279 PLWH, and population PK analysis was performed using Monolix software. A stepwise covariate model-building strategy was used to evaluate any relevant effects of age, body weight, gender, total bilirubin, smoking status, formulations of DTG, morning versus evening dosing, backbone therapy, and other comedications including CYP/UGT inducers/inhibitors.

RESULTS

For a typical 70-kg PLWH, the apparent clearance (CL/F) and apparent volume of distribution (V/F) were 0.748 L/h and 14.6 L, respectively. Of the demographic factors evaluated, body weight was a significant covariate for CL/F and for V/F. Smokers had a 17% higher CL/F relative to nonsmokers. Both strong enzyme inhibitors (eg, atazanavir) and inducers (eg, rifampicin) had marked effects on DTG exposure, with potential clinical implications. Ritonavir-boosted darunavir was found to moderately increase clearance of DTG by 23%. No significant effect of ABC-based backbone therapy was observed on the PK parameters of DTG.

CONCLUSIONS

Our results did not support the hypothesis that ABC, by competing with the DTG metabolic pathway, may significantly increase DTG exposure leading to potential drug toxicity.

Discovery and Development of Anti-HIV Therapeutic Agents: Progress Towards Improved HIV Medication

The history of the human immunodeficiency virus (HIV)/AIDS therapy, which spans over 30 years, is one of the most dramatic stories of science and medicine leading to the treatment of a disease. Since the advent of the first AIDS drug, AZT or zidovudine, a number of agents acting on different drug targets, such as HIV enzymes (e.g. reverse transcriptase, protease, and integrase) and host cell factors critical for HIV infection (e.g. CD4 and CCR5), have been added to our armamentarium to combat HIV/AIDS. In this review article, we first discuss the history of the development of anti-HIV drugs, during which several problems such as drug-induced side effects and the emergence of drug-resistant viruses became apparent and had to be overcome. Nowadays, the success of Combination Antiretroviral Therapy (cART), combined with recently-developed powerful but nonetheless less toxic drugs has transformed HIV/AIDS from an inevitably fatal disease into a manageable chronic infection. However, even with such potent cART, it is impossible to eradicate HIV because none of the currently available HIV drugs are effective in eliminating occult “dormant” HIV cell reservoirs. A number of novel unique treatment approaches that should drastically improve the quality of life (QOL) of patients or might actually be able to eliminate HIV altogether have also been discussed later in the review.

Selection of 2'-Deoxy-2'-Fluoroarabino Nucleic Acid (FANA) Aptamers That Bind HIV-1 Integrase with Picomolar Affinity

Systematic Evolution of Ligands by Exponential Enrichment (SELEX) is the iterative process by which nucleic acids that can bind with high affinity and specificity (termed aptamers) to specific protein targets are selected. Using a SELEX protocol adapted for Xeno-Nucleic Acid (XNA) as a suitable substrate for aptamer generation, 2′-fluoroarabinonucleic acid (FANA) was used to select several related aptamers to HIV-1 integrase (IN). IN bound FANA aptamers with equilibrium dissociation constants (K_D,app) of ∼50–100 pM in a buffer with 200 mM NaCl and 6 mM MgCl₂. Comparisons to published HIV-1 IN RNA and DNA aptamers as well as IN genomic binding partners indicated that FANA aptamers bound more than 2 orders of magnitude more tightly to IN. Using a combination of RNA folding algorithms and covariation analysis, all strong binding aptamers demonstrated a common four-way junction structure, despite significant sequence variation. IN aptamers were selected from the same starting library as FA1, a FANA aptamer that binds with pM affinity to HIV-1 Reverse Transcriptase (RT). It contains a 20-nucleotide 5′ DNA sequence followed by 59 FANA nucleotides. IN-1.1 (one of the selected aptamers) potently inhibited IN activity and intasome formation in vitro. Replacing the FANA nucleotides of IN-1.1 with 2′-fluororibonucleic acid (F-RNA), which has the same chemical formula but with a ribose rather than arabinose sugar conformation, dramatically reduced binding, suggesting that FANA adopts unique structural conformations that promote binding to HIV-1 IN.

Caffeic acid phenethyl ester (CAPE): pharmacodynamics and potential for therapeutic application

Caffeic acid phenethyl ester (CAPE) is the major pharmacologically-active component of some propolis types, rich in polyphenols, such as poplar propolis types. CAPE has the potential to be applied as a pharmaceutical as it possesses most of the pharmacological activities of propolis, such as anti-proliferative, antioxidant, immunomodulatory, antidiabetic, anti-inflammatory and antimicrobial. Its advantage is that it lacks some of the downsides of total propolis extracts, such as inability for unified standardization, which is cornerstone for implementing its therapeutic potential as a drug. The current paper provides an overview on the pharmacodynamic principles of CAPE. We present literature search outcomes form ClinicalTrials.gov database and from scientific publications, available on Scopus and Crossref databases. We take a round view of CAPE’s potential therapeutic implications in light of approved drugs with related modes of action.

A case report of untreatable HIV infection in Harare, Zimbabwe

Introduction

Zimbabwe, like other resource limited countries, manages HIV infection using the public health approach with standard antiretroviral therapy (ART) regimens for first, second and third-line treatment. Third-line ART is the last available treatment option and is based on dolutegravir and darunavir use after HIV drug resistance testing.

Patient Presentation

We report here a 17-year-old patient on dolutegravir (DTG) and Darunavir based third-line antiretroviral therapy (ART) previously exposed to raltegravir who develops multidrug resistance HIV to the four ART classes available in Zimbabwe.

Management and Outcome

A trophism assay revealed that patient has CXCR4 trophic virus and hence will not benefit from Maraviroc. Patient is currently stable and receiving a holding regimen of abacavir, lamivudine and lamivudine.

Conclusion

This is the first documented case of multiclass resistance to the four available ART classes in Zimbabwe. The development and transmission of multiclass HIV drug resistance in resource limited settings has potential to undo the gains of national ART programs. There is need to ensure optimum adherence to ART even in the era of DTG.

Novel Central Nervous System (CNS)-Targeting Protease Inhibitors for Drug-Resistant HIV Infection and HIV-Associated CNS Complications

There is currently no specific therapeutics for the HIV-1-related central nervous system (CNS) complications. Here we report that three newly designed CNS-targeting HIV-1 protease inhibitors (PIs), GRL-083-13, GRL-084-13, and GRL-087-13, which contain a P1-3,5-bis-fluorophenyl or P1-para-monofluorophenyl ring, and P2-bis-tetrahydrofuran (bis-THF) or P2-tetrahydropyrano-tetrahydrofuran (Tp-THF), with a sulfonamide isostere, are highly active against wild-type HIV-1 strains and primary clinical isolates (50% effective concentration [EC₅₀], 0.0002 to ∼0.003 μM), with minimal cytotoxicity. These CNS-targeting PIs efficiently suppressed the replication of HIV-1 variants (EC₅₀, 0.002 to ∼0.047 μM) that had been selected to propagate at high concentrations of conventional HIV-1 PIs. Such CNS-targeting PIs maintained their antiviral activity against HIV-2_ROD as well as multidrug-resistant clinical HIV-1 variants isolated from AIDS patients who no longer responded to existing antiviral regimens after long-term therapy. Long-term drug selection experiments revealed that the emergence of resistant-HIV-1 against these CNS-targeting PIs was substantially delayed. In addition, the CNS-targeting PIs showed the most favorable CNS penetration properties among the tested compounds, including various FDA-approved anti-HIV-1 drugs, as assessed with the in vitro blood-brain barrier reconstruction system. Crystallographic analysis demonstrated that the bicyclic rings at the P2 moiety of the CNS-targeting PIs form strong hydrogen-bond interactions with HIV-1 protease (PR) active site. Moreover, both the P1-3,5-bis-fluorophenyl and P1-para-monofluorophenyl rings sustain greater van der Waals contacts with PR than in the case of darunavir (DRV). The data suggest that the present CNS-targeting PIs have desirable features for treating patients infected with wild-type and/or multidrug-resistant HIV-1 strains and might serve as promising preventive and/or therapeutic candidates for HIV-1-associated neurocognitive disorders (HAND) and other CNS complications.

Effectiveness of Once/Day Dolutegravir Plus Boosted Darunavir as a Switch Strategy in Heavily Treated Patients with Human Immunodeficiency Virus

STUDY OBJECTIVE

Dual therapy with once/day dolutegravir (DTG) plus boosted darunavir (DRV/b) may be a suitable and effective strategy with a high genetic barrier to resistance in patients infected with human immunodeficiency virus (HIV). Our aim was to evaluate the effectiveness of DTG plus DRV/b (DTG+DRV/b) as a switch strategy in HIV-infected patients, irrespective of their history of virologic failure (VF).

DESIGN

Multicenter retrospective cohort study.

SETTING

Human immunodeficiency outpatient treatment clinics at three university hospitals in Spain.

PATIENTS

Fifty HIV-infected adults who had a stable antiretroviral treatment (ART) regimen and an undetectable viral load for at least 6 months, and whose ART was switched to once/day DTG+DRV/b between January 2015 and January 2018 were included in the analysis. Historical genotype at the time of VF was available in 44 patients.

MEASUREMENTS AND MAIN RESULTS

Patients were followed until VF or treatment discontinuation for any reason. The primary outcome was the percentage of patients with a viral load of 50 copies/mL or lower at the last follow-up visit. Secondary outcomes included changes in CD4⁺ cell count, lipid profile, and renal function. Of the 50 patients included, median time of viral suppression was 52 months (interquartile range [IQR] 18-103 mo) and nadir CD4⁺ 89 cells/mm³ (IQR 37-241 cells/mm³ ). Patients had a history of a median of 8 ART combinations (IQR 4-11 combinations) and 3 VFs (IQR 2-8 VFs). The historical genotypes from 44 patients showed 41 patients (93.2%) with nucleoside/nucleotide reverse transcriptase inhibitor (NRTI) resistance-associated mutations (RAMs), 32 (72.7%) with nonnucleoside reverse transcriptase inhibitor (NNRTI) RAMs, and 12 (27.3%) with primary protease inhibitor (PI) RAMs; 7 (15.9%) had darunavir RAMs, and no patients had baseline integrase strand transfer inhibitor RAMs. Thirty-seven patients (84.1%) had resistance to at least two antiretroviral classes. After a median of 25 months (IQR 17-28 mo) of follow-up, 49 patients (98%) maintained a viral load of 50 copies/mL or lower, and 1 patient (2%) had VF. No new RAMs emerged at VF. At week 4, serum creatinine concentration increased a median of 0.12 mg/dl (0.03-0.23 mg/dl). At last visit, total cholesterol and low-density lipoprotein cholesterol levels increased by a median of 9 mg/dl (IQR -18 to 40 mg/dl) and 16 mg/dl (IQR -9 to 40 mg/dl), respectively, whereas CD4⁺ cell count remained stable (median +13 cell/mm³ ).

CONCLUSION

In this cohort of heavily treated HIV-infected patients with virologic suppression, switching to the combination of DTG+DRV/b was a convenient regimen that was highly effective and had good tolerability.

Pharmacokinetics and Safety of the Integrase Inhibitors Elvitegravir and Dolutegravir in Pregnant Women With HIV

Objective: To synthesize data on the pharmacokinetics and safety of dolutegravir and elvitegravir in pregnant women living with HIV. Data Sources: A PubMed, EMBASE, Web of Science, and Google Scholar literature search (January 2010 to December 2018) was performed using the search terms dolutegravir, elvitegravir, women, pregnant*, and HIV. Additional reports were identified from conference abstracts and review of reference lists. Study Selection and Data Extraction: English-language studies reporting pharmacokinetic and/or safety data in pregnant women receiving dolutegravir or elvitegravir/cobicistat were included. Data Synthesis: A total of 17 studies were selected. Studies demonstrated a modest decrease in dolutegravir concentrations in pregnancy. Preliminary data suggest an increased risk of neural tube defects when dolutegravir is used at the time of conception. Available pharmacokinetic data in pregnant women showed significantly reduced plasma concentrations of elvitegravir/cobicistat which may increase the risk of virological failure. Current guidelines recommend that dolutegravir should not be initiated in women who have the potential to become pregnant or women in their first trimester of pregnancy and elvitegravir/cobicistat should be avoided during pregnancy. Relevance to Patient Care and Clinical Practice: This review highlights pharmacokinetic and safety data for dolutegravir and elvitegravir/cobicistat in pregnant women. Clinicians need to be aware of these data to convey the risks and benefits of using these agents in women of child-bearing potential. Conclusions: Changes in guideline recommendations reflect emerging data regarding the use of dolutegravir and elvitegravir/cobicistat in pregnancy. Until further information is available, raltegravir or other first-line agents are recommended for women with HIV planning to become pregnant.

Recent advances in the discovery of small-molecule inhibitors of HIV-1 integrase

AIDS caused by the infection of HIV is a prevalent problem today. Rapid development of drug resistance to existing drug classes has called for the discovery of new targets. Within the three major enzymes (i.e., HIV-1 protease, HIV-1 reverse transcriptase and HIV-1 integrase [IN]) of the viral replication cycle, HIV-1 IN has been of particular interest due to the absence of human cellular homolog. HIV-1 IN catalyzes the integration of viral genetic material with the host genome, a key step in the viral replication process. Several novel classes of HIV IN inhibitors have been explored by targeting different sites on the enzyme. This review strives to provide readers with updates on the recent developments of HIV-1 IN inhibitors.

AIDS is an epidemic disease that endangers the lives of millions of people across the world. The AIDS virus, also known as HIV, has developed resistance to the majority of available drugs on the market, thus requiring the need for new drugs. HIV integrase is one of the key viral enzymes required for viral cell proliferation. Since there is no similar enzyme in the human body, major emphasis is being made to develop therapeutics for this novel target. The drugs that are at various stages of development for this target are reviewed here.

Drug resistance mutations in HIV-2 patients failing raltegravir and influence on dolutegravir response

Background

A broader extent of amino acid substitutions in the integrase of HIV-2 compared with HIV-1 might enable greater cross-resistance between raltegravir and dolutegravir in HIV-2 infection. Few studies have examined the virological response to dolutegravir in HIV-2 patients that failed raltegravir.

Methods

All patients recorded in the HIV-2 Spanish cohort were examined. The integrase coding region was sequenced in viraemic patients. Changes associated with resistance to raltegravir and dolutegravir in HIV-1 were recorded.

Results

From 319 HIV-2-infected patients recorded in the HIV-2 Spanish cohort, 53 integrase sequences from 30 individuals were obtained (20 raltegravir naive and 10 raltegravir experienced). Only one secondary mutation (E138A) was found in one of the 20 raltegravir-naive HIV-2 patients. For raltegravir-experienced individuals, the resistance mutation profile in 9 of 10 viraemic patients was as follows: N155H + A153G/S (four); Y143G + A153S (two); Q148R + G140A/S (two); and Y143C + Q91R (one). Of note, all patients with Y143G and N155H developed a rare non-polymorphic mutation at codon 153. Rescue therapy with dolutegravir was given to 5 of these 10 patients. After >6 months on dolutegravir therapy, three patients with baseline N155H experienced viral rebound. In two of them N155H was replaced by Q148K/R and in another by G118R.

Conclusions

A wide repertoire of resistance mutations in the integrase gene occur in HIV-2-infected patients failing on raltegravir. Although dolutegravir may allow successful rescue in most HIV-2 raltegravir failures, we report and characterize three cases of dolutegravir resistance in HIV-2 patients, emerging variants Q148K and Q148R and a novel change G118R.

Virologic suppression and CD4+ cell count recovery after initiation of raltegravir or efavirenz-containing HIV treatment regimens

OBJECTIVE

To explore the effectiveness of raltegravir-based antiretroviral therapy (ART) on treatment response among ART-naive patients seeking routine clinical care.

DESIGN

Cohort study of adults enrolled in HIV care in the United States.

METHODS

We compared virologic suppression and CD4 cell count recovery over a 2.5 year period after initiation of an ART regimen containing raltegravir or efavirenz using observational data from a US clinical cohort, generalized to the US population of people with diagnosed HIV. We accounted for nonrandom treatment assignment, informative censoring, and nonrandom selection from the US target population using inverse probability weights.

RESULTS

Of the 2843 patients included in the study, 2476 initiated the efavirenz-containing regimen and 367 initiated the raltegravir-containing regimen. In the weighted intent-to-treat analysis, patients spent an average of 74 (95% confidence interval: 41, 106) additional days alive with a suppressed viral load on the raltegravir regimen than on the efavirenz regimen over the 2.5-year study period. CD4 cell count recovery was also superior under the raltegravir regimen.

CONCLUSION

Patients receiving raltegravir spent more time alive and suppressed than patients receiving efavirenz, but the probability of viral suppression by 2.5 years after treatment was similar between groups. Optimizing the amount of time spent in a state of viral suppression is important to improve survival among people living with HIV and to reduce onward transmission.

GRL-09510, a Unique P2-Crown-Tetrahydrofuranylurethane -Containing HIV-1 Protease Inhibitor, Maintains Its Favorable Antiviral Activity against Highly-Drug-Resistant HIV-1 Variants in vitro

We report that GRL-09510, a novel HIV-1 protease inhibitor (PI) containing a newly-generated P2-crown-tetrahydrofuranylurethane (Crwn-THF), a P2′-methoxybenzene, and a sulfonamide isostere, is highly active against laboratory and primary clinical HIV-1 isolates (EC₅₀: 0.0014–0.0028 μM) with minimal cytotoxicity (CC₅₀: 39.0 μM). Similarly, GRL-09510 efficiently blocked the replication of HIV-1_NL4-3 variants, which were capable of propagating at high-concentrations of atazanavir, lopinavir, and amprenavir (APV). GRL-09510 was also potent against multi-drug-resistant clinical HIV-1 variants and HIV-2_ROD. Under the selection condition, where HIV-1_NL4-3 rapidly acquired significant resistance to APV, an integrase inhibitor raltegravir, and a GRL-09510 congener (GRL-09610), no variants highly resistant against GRL-09510 emerged over long-term in vitro passage of the virus. Crystallographic analysis demonstrated that the Crwn-THF moiety of GRL-09510 forms strong hydrogen-bond-interactions with HIV-1 protease (PR) active-site amino acids and is bulkier with a larger contact surface, making greater van der Waals contacts with PR than the bis-THF moiety of darunavir. The present data demonstrate that GRL-09510 has favorable features for treating patients infected with wild-type and/or multi-drug-resistant HIV-1 variants, that the newly generated P2-Crwn-THF moiety confers highly desirable anti-HIV-1 potency. The use of the novel Crwn-THF moiety sheds lights in the design of novel PIs.

A Modified P1 Moiety Enhances In Vitro Antiviral Activity against Various Multidrug-Resistant HIV-1 Variants and In Vitro Central Nervous System Penetration Properties of a Novel Nonpeptidic Protease Inhibitor, GRL-10413

We report here that GRL-10413, a novel nonpeptidic HIV-1 protease inhibitor (PI) containing a modified P1 moiety and a hydroxyethylamine sulfonamide isostere, is highly active against laboratory HIV-1 strains and primary clinical isolates (50% effective concentration [EC₅₀] of 0.00035 to 0.0018 μM), with minimal cytotoxicity (50% cytotoxic concentration [CC₅₀] = 35.7 μM). GRL-10413 blocked the infectivity and replication of HIV-1_NL4-3 variants selected by use of atazanavir, lopinavir, or amprenavir (APV) at concentrations of up to 5 μM (EC₅₀ = 0.0021 to 0.0023 μM). GRL-10413 also maintained its strong antiviral activity against multidrug-resistant clinical HIV-1 variants isolated from patients who no longer responded to various antiviral regimens after long-term antiretroviral therapy. The development of resistance against GRL-10413 was significantly delayed compared to that against APV. In addition, GRL-10413 showed favorable central nervous system (CNS) penetration properties as assessed with an in vitro blood-brain barrier (BBB) reconstruction system. Analysis of the crystal structure of HIV-1 protease in complex with GRL-10413 demonstrated that the modified P1 moiety of GRL-10413 has a greater hydrophobic surface area and makes greater van der Waals contacts with active site amino acids of protease than in the case of darunavir. Moreover, the chlorine substituent in the P1 moiety interacts with protease in two distinct configurations. The present data demonstrate that GRL-10413 has desirable features for treating patients infected with wild-type and/or multidrug-resistant HIV-1 variants, with favorable CNS penetration capability, and that the newly modified P1 moiety may confer desirable features in designing novel anti-HIV-1 PIs.

Two case reports of severe myocarditis associated with the initiation of dolutegravir treatment in HIV patients

RATIONALE

The integrase inhibitor dolutegravir is now recommended as first-line treatment for HIV. A single case of myocarditis after treatment with dolutegravir was reported in the FLAMINGO trial. We present here 2 cases of severe myocarditis that occurred shortly after the initiation of dolutegravir treatment.

PATIENTS CONCERNS

The first case is a 45-year-old female who developed severe congestive heart failure and died, weeks after the initiation of dolutegravir treatment (for simplification of her antiretroviral regimen). The second case was a 51-year-old male who presented with effort dyspnea 3 weeks after the initiation of dolutegravir treatment and was later diagnosed as severe congestive heart failure. The treatment was changed and the patient survived, but he still suffers from severe heart failure with functional impairment.

DIAGNOSIS AND OUTCOME

Patient 1 died, patient 2 suffers from severe heart failure.

LESSONS

We discuss here the possible relationship between the initiation of dolutegravir treatment and the development of lymphocytic myocarditis in our patients, and we suggest a possible mechanism.

Role of phenotypic investigation in the era of routine genotypic HIV-1 drug resistance testing

The emergence of drug resistance can seriously compromise HIV type-1 therapy and decrease therapeutic options. Resistance testing is highly recommended to guide treatment decisions and drug activity can be accurately predicted in the clinical setting through genotypic assays. While phenotypic systems are not suitable for monitoring drug resistance in routine laboratory practice, genotyping can misclassify unusual or complex mutational patterns, particularly with recently approved antivirals. In addition, phenotypic assays remain fundamental for characterizing candidate antiretroviral compounds. This review aims to discuss how phenotypic assays contributed to and still play a role in understanding the mechanisms of resistance of both licensed and investigational HIV type-1 inhibitors.

Successful Treatment of Mitochondrial Toxicity in an HIV-Positive Patient After Liver Transplantation

Liver transplantation in patients infected with the human immunodeficiency virus (HIV) has been increasingly performed with reasonable outcomes; however, medical management of both immunosuppression and antiretroviral therapy can be challenging owing to drug toxicities and interactions. Nucleoside reverse transcriptase inhibitors (NRTIs), a common backbone of highly active antiretroviral therapy (HAART), were the first class of effective antiretroviral drugs developed. NRTIs are commonly used for posttransplant HAART therapy and have a rare but fatal complication of mitochondrial toxicity, manifesting as severe lactic acidosis, hepatic steatosis, and lipoatrophy. Herein, we have reported on the first known successful treatment of severe mitochondrial toxicity secondary to NRTIs in an HIV-infected transplant recipient.