Short Communication: Dolutegravir-Based Regimens Are Active in Integrase Strand Transfer Inhibitor-Naive Patients with Nucleoside Reverse Transcriptase Inhibitor Resistance

HIV-1 Low-Frequency Variants Identified in Antiretroviral-Naïve Subjects with Virologic Failure after 12 Months of Follow-Up in Panama

Low-frequency mutations associated with drug resistance have been related to virologic failure in subjects with no history of pre-treatment and recent HIV diagnosis. In total, 78 antiretroviral treatment (ART)-naïve subjects with a recent HIV diagnosis were selected and followed by CD4+ T lymphocytes and viral load tests to detect virologic failure. We sequenced the basal samples retrospectively using next-generation sequencing (NGS), looking for low-frequency mutations that had not been detected before using the Sanger sequencing method (SSM) and describing the response to ART. Twenty-two subjects developed virologic failure (VF), and thirteen of them had at least one drug-resistance mutation associated with Reverse Transcriptase Inhibitors (RTI) and Protease Inhibitors (PIs) at frequency levels ≤ 1%, not detected previously in their basal genotyping test. No resistance mutations were observed to Integrase Strand Transfer Inhibitors (INSTIs). We identified a possible cause of VF in ART-naïve subjects with low-frequency mutations detected. To our knowledge, this is the first evaluation of pre-existing drug resistance for HIV-1 minority variants carried out on ART-naïve people living with HIV/AIDS (PLWHA) by analyzing the HIV-1 pol gene using NGS in the country.

Rate of virological failure and HIV-1 drug resistance among HIV-infected adolescents in routine follow-up on health facilities in Cameroon

The objective of this study was to determine the rates of virological failure (VF) and HIV drug resistance (HIVDR) amongst adolescents on antiretroviral Therapy (ART). A retrospectively designed study was conducted in 10 healthcare centers for adolescents living with HIV (ALHIV) in the two main cities of Cameroon (Yaoundé and Douala), from November 2018 to May 2019. Sociodemographic, clinical, therapeutic and laboratory parameters were collected from medical records. All enrolled ALHIV had viral load (VL) measurements following the national guidelines. All patients with a VL ≥ 1000 copies/ml were called to perform genotyping tests. The chi-square test was used to determine the factors associated with VF. Out of the 1316 medical records of ALHIV, we included 1083 ALHIV having a VL result. Among them, 276 (25.5%) were experiencing VF, and VF was significantly higher in ALHIV with suboptimal adherence (p<0.001), older adolescents (p<0.05), those who lived outside the city where they were receiving ART (p<0.006), severely immunocompromised (p<0.01) and started ART at infancy (p<0.02). Among the 45/276 (16.3%) participants with an available genotyping resistance testing (GRT) result, the overall rate of HIVDR was 93.3% (42/45). The most common mutations were K103N (n = 21/42, 52.3%) resulting in high-level resistance to Efavirenz and Nevirapine, followed by M184V (n = 20/42, 47.6%) and thymidine analog mutations (n = 15/42, 35.7%) associated with high-level resistance to Lamivudine and Zidovudine respectively. The high rate of VF and HIVDR among ALHIV regularly followed in health facilities in Cameroon highlights the need to develop interventions adapted to an adolescent-centered approach to preserve future ART options.

Switching to Bictegravir, Emtricitabine, and Tenofovir Alafenamide in Virologically Suppressed Adults With Human Immunodeficiency Virus

Background

Bictegravir (B)/emtricitabine (F)/tenofovir alafenamide (TAF) is guideline-recommended treatment for human immunodeficiency virus type 1 (HIV-1). We evaluated whether people receiving dolutegravir (DTG) plus F/TAF or F/TDF (tenofovir disoproxil fumarate) with viral suppression can switch to B/F/TAF without compromising safety or efficacy, regardless of preexisting nucleoside reverse transcriptase inhibitor (NRTI) resistance.

Methods

In this multicenter, randomized, double-blinded, active-controlled, noninferiority trial, we enrolled adults who were virologically suppressed for ≥6 months before screening (with documented/suspected NRTI resistance) or ≥3 months before screening (with no documented/suspected NRTI resistance) on DTG plus either F/TDF or F/TAF. We randomly assigned (1:1) participants to switch to B/F/TAF or DTG + F/TAF once daily for 48 weeks, each with matching placebo. The primary endpoint was proportion of participants with plasma HIV-1 RNA ≥50 copies/mL at week 48 (snapshot algorithm); the prespecified noninferiority margin was 4%.

Results

Five hundred sixty-seven adults were randomized; 565 were treated (284 B/F/TAF, 281 DTG + F/TAF). At week 48, B/F/TAF was noninferior to DTG + F/TAF, as 0.4% (1/284) vs 1.1% (3/281) had HIV-1 RNA ≥50 copies/mL (difference, −0.7% [95.001% confidence interval {CI}, −2.8% to 1.0%]). There were no significant differences in efficacy among participants with suspected or confirmed prior NRTI resistance (n = 138). No participant had treatment-emergent drug resistance. Median weight change from baseline at week 48 was +1.3 kg (B/F/TAF) vs +1.1 kg (DTG + F/TAF) (P = .46). Weight change differed by baseline NRTIs (+2.2 kg [F/TDF] and +0.6 kg [F/TAF], P < .001), with no differences between B/F/TAF and DTG + F/TAF.

Conclusions

The single-tablet regimen B/F/TAF is a safe, effective option for people virologically suppressed on DTG plus either F/TDF or F/TAF, including in individuals with preexisting resistance to NRTIs.

Clinical Trials Registration

NCT03110380.

A patient-centred approach to deprescribing antiretroviral therapy in people living with HIV

Only a few studies have explored the benefit of deprescribing in people living with HIV (PLWH), focusing on the discontinuation of non-antiretrovirals (non-ARVs) used for HIV-associated comorbidities (co-medications), or the management of drug-drug interactions (DDIs) between ARVs or between ARVs and co-medications. The availability of modern single-tablet regimens, two-drug regimens and long-acting therapy opens a discussion regarding ARV deprescribing strategies. The objective of this article is to discuss ARV deprescribing strategies in the context of medication-related burden and patients' lived experience with medicine (PLEM) and to suggest indications for whom, when, how and why to consider these ARV options in PLWH. A PLEM construct helps to better interpret these strategies and provides a patient-centred precision-medicine approach. There are several safe and virologically effective ARV deprescribing strategies, but the ultimate benefits of these interventions still need to be further explored in terms of the overall health and quality of life of patients.

Dolutegravir Plus Lamivudine Two-Drug Regimen: Safety, Efficacy and Diagnostic Considerations for Its Use in Real-Life Clinical Practice-A Refined Approach in the COVID-19 Era

The diagnostic and therapeutic management of the Coronavirus Disease 2019 (COVID-19) pandemic in the HIV population brought some known criticalities (and opportunities) to the forefront, for both those who are facing their first therapeutic line today, and for those already well viro-suppressed. The clinical, socioeconomic, and psychological impact of the COVID-19 pandemic should not affect the long-term care of people living with HIV, which creates an urgent need to optimize the diagnostic and treatment approach to the first-line or switch regimens. The use of dolutegravir plus a lamivudine two-drug regimen is one of the most promising solutions to ease the management of HIV treatment in this difficult period. In this review, we report the most salient features related to the use of this regimen from real-life cohorts, meta-analyses, randomized clinical trials, and studies presented at international conferences up to March 2021. We focused on the diagnostic and clinical-management implications of its use in real life, and how these comply with the contingent historical situation. The issue of the timing and type of diagnostic procedures and the relevance of classical diagnostic tests (such as genotype for resistance detection) is also discussed. According to the currently available results, dolutegravir plus a lamivudine two-drug regimen represents an outstanding tool, whose expected advantages fulfill the current requirements for optimal daily care of our HIV patients.

Impact of NRTI resistance mutations on virological effectiveness of antiretroviral regimens containing elvitegravir: a multi-cohort study

BACKGROUND

Antiretroviral drug resistance mutations remain a major cause of treatment failure.

OBJECTIVES

To evaluate the impact of NRTI resistance mutations on virological effectiveness of elvitegravir-containing regimens.

MATERIALS AND METHODS

We selected treatment-experienced HIV-1-infected patients starting elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide (E/C/F/TAF) or elvitegravir/cobicistat/emtricitabine/tenofovir disoproxil fumarate (E/C/F/TDF), with at least one protease/reverse transcriptase genotype available before switching and at least one HIV-1 RNA viral load (VL) measurement during follow-up. The primary endpoint was virological failure (VF), defined as one VL value of ≥1000 copies/mL or two consecutive VL values of >50 copies/mL.

RESULTS

We included 264 ART regimens: 75.6% male, median (IQR) age 47 years (39-53), 7 years (3-16) of HIV infection, nadir CD4+ 247 cells/mm3 (105-361), 81.5% with VL ≤50 copies/mL and 11.7% with at least one NRTI mutation at baseline. Eleven (5.2%) VFs occurred in virologically suppressed patients versus eight (15.1%) in viraemic patients. The estimated probability of VF at 48 weeks with versus without any NRTI mutation was 7.4% (95% CI 2.3-12.5) versus 3.8% (2.1-5.5) in virologically suppressed patients and 66.7% (39.5-93.9) versus 11.2% (6.5-15.9) (P<0.001) in viraemic patients. The only predictor of VF was time on therapy (per 1 year more, adjusted HR 1.14, 95% CI 1.02-1.27, P=0.024) in viraemic patients.

CONCLUSIONS

A switch to E/C/F/TDF or E/C/F/TAF is safe for virologically suppressed patients without documented NRTI resistance, but not recommended in viraemic patients with a history of NRTI resistance. Although we did not detect a detrimental effect of past NRTI resistance in virologically suppressed patients, a fully active regimen remains preferred in this setting due to possible rebound of drug-resistant virus in the long term.

HIV Drug Resistance in Children and Adolescents: Always a Challenge?

Purpose of Review

With the expanded roll-out of antiretrovirals for treatment and prevention of HIV during the last decade, the emergence of HIV drug resistance (HIVDR) has become a growing challenge. This review provides an overview of the epidemiology and trajectory of HIVDR globally with an emphasis on pediatric and adolescent populations.

Recent Findings

HIVDR is associated with suboptimal virologic suppression and treatment failure, leading to an increased risk of HIV transmission to uninfected people and increased morbidity and mortality among people living with HIV. High rates of HIVDR to non-nucleoside reverse transcriptase inhibitors globally are expected to decline with the introduction of the integrase strand transfer inhibitors and long-acting combination regimens, while challenge remains for HIVDR to other classes of antiretroviral drugs.

Summary

We highlight several solutions including increased HIV viral load monitoring, expanded HIVDR surveillance, and adopting antiretroviral regimens with a high-resistance barrier to decrease HIVDR. Implementation studies and programmatic changes are needed to determine the best approach to prevent and combat the development of HIVDR.

Treatment Experience and Repeat Pregnancy Impact the Effectiveness of Non-Nucleoside Reverse Transcription Inhibitor-Highly Active Antiretroviral Therapy for the Prevention of Mother to Child Transmission of Human Immunodeficiency Virus

Non-nucleoside reverse transcription inhibitor (NNRTI)-containing antiretroviral therapy (ART) for the prevention of mother to child transmission (PMTCT) of human immunodeficiency virus (HIV) has led to dramatic reductions in perinatal HIV infection in resource-constrained settings. Nonetheless, PMTCT programs are complicated by repeat pregnancies, in which long-term or repeat exposures to PMTCT regimens over time may lead to the acquisition of HIV drug resistance mutations, and consequent treatment failure. In this study, we retrospectively assessed the effectiveness of the NNRTI-based PMTCT protocol from 2008 to 2010 in The Bahamas National HIV/AIDS Program. We show that women who had been in repeat pregnancies and those who were already prescribed ART at conception were at increased risk of virologic failure, relative to treatment-inexperienced women and primigravida, respectively (AOR 3.1, 95% CI: 1.3-7.1, p = .008 and AOR 5.0, 95% CI: 1.8-14.1, p = .002). In addition, women undergoing treatment at conception were more likely to possess HIVDR mutations relative to treatment-naive women (AOR 447.1, 95% CI: 17.9-11,173.5, p = .001). Therefore, individual treatment history is a key metric determining the effectiveness of current and future PMTCT interventions. The implications of this to PMTCT programmatic success in light of the most recent WHO guidelines are discussed.

Viro-immunological efficacy and tolerability of dolutegravir-based regimens compared to regimens based on other integrase strand inhibitors, protease inhibitors or non-nucleoside reverse transcriptase inhibitors in patients with acute HIV-1 infection: A multicenter retrospective cohort study

OBJECTIVES

The aim of this study was to compare the tolerability and viro-immunological efficacy of dolutegravir-based regimens (DTG group) with regimens based on EVG, RAL, PI or NNRTI (NODTG group) in patients with acute HIV-1 infections (AHI).

METHODS

All patients diagnosed with AHI and on antiretroviral therapy (ART) between January 2015 and December 2017 from five centers in Italy were included and followed-up to 30^th April 2018. AHI was defined by the presence of the positive p24 antigen with negative or indeterminate western blot.

RESULTS

Forty-three patients were enrolled: 20 in the DTG group, 23 in the NODTG group. Nine patients (20.9%; four in the DTG group, five in the NODTG group) were prescribed a four-drug regimen. In the cohort, 81.4% were Italian and 83.7% were male, with a median age of 41 years (interquartile range [IQR] 31-48). Median time between HIV diagnosis and ART initiation was 12 days (IQR 5-28). Seven patients harbored a virus with transmitted mutations at baseline (16.2%), all were in the DTG group (P=0.005). All patients had undetectable HIV-RNA at the end of follow-up except two patients, one of whom had 57 copies and one who was lost to follow-up. In Kaplan-Meier analysis, time to virological suppression was similar in the two groups (log rank: P= 0.7155). After achieving virological suppression, four patients stopped ART because of toxicity: two on DTG, two on EVG for neurological and gastrointestinal toxicity, respectively.

CONCLUSION

In our setting, ART in AHI is started very early. DTG showed good viro-immunological efficacy even in the presence of NRTI-transmitted mutations. DTG interruptions were rare.

Absence of Integrase Strand Transfer Inhibitor Associated Resistance in Antiretroviral Therapy Naïve and Experienced Individuals from Western India

The Indian national AIDS control program heavily relies on low cost nucleoside reverse transcriptase inhibitor (NRTI) and non-nucleoside reverse transcriptase inhibitor (NNRTI). With global increase in resistance to these, alternative antiretroviral combinations need to be explored. Owing to higher potency, better efficacy and tolerability, recently WHO recommended integrase strand transfer inhibitor (INSTI) based first-line antiretroviral therapy (ART). There is lack of INSTI resistance surveillance data from India. Thus, there is a need to analyze integrase (IN) gene from primarily HIV-1 subtype C infected Indian population, before widespread introduction of INSTI in first-line ART. Plasma samples were collected from INSTI naïve individuals reporting to ART centre of Pune, India. RNA was extracted and IN gene was amplified by nested polymerase chain reaction (PCR) using prior published primers. PCR product of 867 bp was bi-directionally sequenced and resistance associated mutation were analyzed using Stanford University HIV drug resistance algorithm. A total of 58 HIV-1 sequences from 62 INSTI naïve individuals were successfully genotyped. Of these 58, 40 were ART naïve, newly diagnosed and remaining individuals were on NRTI, NNRTI, or protease inhibitors based failing regimen. The commonest subtype identified in the study was C (93%) followed by A1 (3.5%). A total of 191 (66.31%) fully conserved amino acid (aa) positions were observed in IN gene. Overall there was absence of major INSTI resistance mutation, however, E157Q (13.79%) emerged as common polymorphic mutation. Other accessory mutations were L74IM (34.48%), Q95K (1.72%), and T97A (1.72%). To conclude, this first Indian study on primarily HIV-1 subtype C sequences characterized aa variations in IN gene and indicated absence of major INSTI resistance associated mutations.

Predicted antiviral activity of tenofovir versus abacavir in combination with a cytosine analogue and the integrase inhibitor dolutegravir in HIV-1-infected South African patients initiating or failing first-line ART

Objectives

The WHO recently recommended the use of a new first-line ART containing dolutegravir. We investigated the efficacy of NRTI backbones (tenofovir or abacavir with a cytosine analogue) in low- and middle-income countries where there is significant prior exposure to antiretrovirals and drug resistance to NRTIs.

Methods

Within the treatment-as-prevention study in South Africa, we selected participants with available next-generation sequencing (NGS) data for the HIV-1 pol gene at trial entry; they were either ART initiators (n = 1193) or already established on ART (n = 94). NGS of the HIV-1 pol gene was carried out using MiSeq technology; reverse transcriptase drug resistance mutations (DRMs) were detected at 5% (DRM5%) and 20% (DRM20%) for all 1287 participants. Genotypic susceptibility was assessed using the Stanford HIVDB resistance interpretation algorithm.

Results

NRTI DRM20% and DRM5% were detected among 5/1193 (0.4%) and 9/1193 (0.8%) of ART initiators, respectively. There was tenofovir exposure in 73/94 (77.7%) of those established on ART, with full susceptibility to abacavir in 57/94 (60.6%) and 56/94 (59.6%) for DRM20% and DRM5%, respectively, while 67/94 (71.3%) and 64/94 (68.1%) were fully susceptible to tenofovir, respectively. The differences between tenofovir and abacavir were not statistically significant at the 20% or 5% variant level (P = 0.16 and 0.29, respectively). NGS detection of variants at the 5% level increased detection of K65R in both naive and treated groups. One of 607 integrase sequences carried a DRM20% (Q148R).

Conclusions

Dolutegravir with a cytosine analogue plus tenofovir or abacavir appears to have similar efficacy in South Africans naive to ART. NGS should be considered in HIV drug resistance surveillance.

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.

Clinical Outcomes Associated With Once-Daily Ritonavir-Boosted Darunavir Plus Tenofovir/Emtricitabine in HIV-Infected Patients Harboring at Minimum a M184V/I Resistance Mutation

BACKGROUND

Limited data exist on the use of a boosted protease inhibitor plus <2 active nucleoside/nucleotide reverse transcriptase inhibitors without use of additional classes of antiretroviral (ARV) therapy in treatment-experienced patients with background resistance.

OBJECTIVE

To evaluate clinical outcomes in HIV-infected patients harboring single- or multiclass resistant virus and receiving once-daily tenofovir/emtricitabine (TDF/FTC) plus darunavir/ritonavir (DRV/r) administered for >24 weeks.

METHODS

This was a single-center chart review of HIV-infected patients receiving daily TDF/FTC plus DRV/r and identified with resistant virus (including, but not limited to, an M184V/I). The primary outcome was HIV viral load (VL) <200 copies/mL (cp/mL) at last measurement. Additional end points included virological rebound (VR), resuppression, or failure (VF); VL <40 cp/mL at last measurement; and development of additional mutations.

RESULTS

Of 171 eligible patients, 32 were included in the study and received DRV 800 mg/r 100 mg daily with fixed-combination TDF/FTC. All patients had a baseline M184V/I mutation, with 10 (31%) having resistance to TDF; 27 (84%) achieved a VL <200 cp/mL, and 25(78%) had a VL <200 cp/mL at the last reading; 22 (69%) achieved a VL <40 cp/mL. VF occurred in 6/32 (19%) patients and VR in 1/32 (3%) patients. Conclusion and Relevance: Although providing a regimen containing ≤2 active drugs, the use of once-daily DRV/r plus TDF/FTC in treatment-experienced patients with single-/multiclass resistant virus resulted in virological suppression in more than three-fourths of patients. These retrospective data suggest that despite the presence of an M184V/I, this combination may be an option in patients seeking a once-daily ARV therapy to improve adherence.

Dolutegravir for first-line antiretroviral therapy in low-income and middle-income countries: uncertainties and opportunities for implementation and research

A new first-line antiretroviral therapy (ART) regimen containing dolutegravir is being rolled out in low-income and middle-income countries (LMICs). In studies from predominantly high-income settings, dolutegravir-based regimens had superior efficacy, tolerability, and durability compared with existing first-line regimens. However, several questions remain about the roll out of dolutegravir in LMICs, where most people with HIV are women of reproductive age, tuberculosis prevalence can be high, and access to viral load and HIV drug resistance testing is limited. Findings from cohort studies suggest that dolutegravir is safe when initiated in pregnancy, but more data are needed to determine the risk of adverse birth outcomes when dolutegravir-based regimens are initiated before conception. Increasing access to viral load testing to monitor the effectiveness of dolutegravir remains crucial, but the best strategy to manage patients with viraemia is unclear. Furthermore, evidence to support the effectiveness of dolutegravir when given with tuberculosis treatment is scarce, particularly in programmatic settings in LMICs. Lastly, whether nucleoside reverse transcriptase inhibitor resistance will affect the long-term efficacy of dolutegravir-based regimens in first-line, and potentially second-line, ART is unknown. Clinical trials, cohorts, and surveillance of HIV drug resistance will be necessary to answer these questions and to maximise the benefits of this new regimen.