Impact of the M184V/I Mutation on the Efficacy of Abacavir/Lamivudine/Dolutegravir Therapy in HIV Treatment-Experienced Patients

Treatment Management Challenges in Naïve and Experienced HIV-1-Infected Individuals Carrying the M184V Mutation

M184V is a single-base mutation in the YMDD domain of reverse transcriptase (RT). The M184V resistance-associated mutation (RAM) is related to virological unresponsiveness to lamivudine (3TC) and emtricitabine (FTC) and induces high-level resistance to these two antiretroviral agents. M184V is rapidly selected in the setting of non-suppressive antiretroviral therapy (ART) and accumulates in the HIV reservoir. There were continuous efforts to evaluate the impact of the M184V mutation on the treatment outcomes in people living with HIV (PLWH). Since 3TC remains an extensively used part of recommended antiretroviral combinations, M184V is commonly detected in patients with virological failure (VF). ART guidelines do not recommend the use of drugs impacted by RAMs as they have been confirmed to comprise a risk factor for VF. However, there is evidence that 3TC/FTC can remain active even in the presence of M184V. Given the potential benefits of 3TC in ART combinations, the investigation of M184V remains of high interest to clinicians and researchers, especially in certain regions with limited resources, and especially for its unusual effects. This is a review of the literature on the challenges in treating both naïve and experienced individuals carrying the M184V mutation, including virological failure, virological suppression, and resistance to ART.

Prevalence of Emergent Dolutegravir Resistance Mutations in People Living with HIV: A Rapid Scoping Review

BACKGROUND

Dolutegravir (DTG) is a cornerstone of global antiretroviral (ARV) therapy (ART) due to its high efficacy and favorable tolerability. However, limited data exist regarding the risk of emergent integrase strand transfer inhibitor (INSTI) drug-resistance mutations (DRMs) in individuals receiving DTG-containing ART.

METHODS

We performed a PubMed search using the term "Dolutegravir", last updated 18 December 2023, to estimate the prevalence of VF with emergent INSTI DRMs in people living with HIV (PLWH) without previous VF on an INSTI who received DTG-containing ART.

RESULTS

Of 2131 retrieved records, 43 clinical trials, 39 cohorts, and 6 cross-sectional studies provided data across 6 clinical scenarios based on ART history, virological status, and co-administered ARVs: (1) ART-naïve PLWH receiving DTG plus two NRTIs; (2) ART-naïve PLWH receiving DTG plus lamivudine; (3) ART-experienced PLWH with VF on a previous regimen receiving DTG plus two NRTIs; (4) ART-experienced PLWH with virological suppression receiving DTG plus two NRTIs; (5) ART-experienced PLWH with virological suppression receiving DTG and a second ARV; and (6) ART-experienced PLWH with virological suppression receiving DTG monotherapy. The median proportion of PLWH in clinical trials with emergent INSTI DRMs was 1.5% for scenario 3 and 3.4% for scenario 6. In the remaining four trial scenarios, VF prevalence with emergent INSTI DRMs was ≤0.1%. Data from cohort studies minimally influenced prevalence estimates from clinical trials, whereas cross-sectional studies yielded prevalence data lacking denominator details.

CONCLUSIONS

In clinical trials, the prevalence of VF with emergent INSTI DRMs in PLWH receiving DTG-containing regimens has been low. Novel approaches are required to assess VF prevalence with emergent INSTI DRMs in PLWH receiving DTG in real-world settings.

Human Immunodeficiency Virus-1 Drug Resistance Mutations in Iranian Treatment-experienced Individuals

BACKGROUND

Human immunodeficiency virus-1 infection still remains a global health threat. While antiretroviral therapy is the primary treatment option, concerns about the emergence of drug-resistance mutations and treatment failure in HIV-infected patients persist.

OBJECTIVE

In this study, we investigated the development of drug resistance in HIV-1-infected individuals receiving antiretroviral therapy for 6-10 years.

METHODS

In this cross-sectional study, we evaluated 144 people living with HIV-1 who had received antiretroviral therapy for at least 6 years. Plasma specimens were collected, and the HIV-1 viral load and drug-resistance mutations were assessed using molecular techniques.

RESULTS

The demographic and epidemiological characteristics of the participants were also analyzed: Twelve [8.3%) of the studied patients showed a viral load over 1000 copies per/mL, which indicates the suboptimal response to antiretroviral therapy. Significant correlations were found between viral load and CD4 count, as well as epidemiological factors, such as vertical transmission, history of imprisonment, and needle stick injuries. Drug resistance mutations were detected in 10 (83.3%) of patients who failed on antiretroviral therapy, with the most common mutations observed against nucleoside reverse transcriptase inhibitors (5 (41.7%)) and non-nucleoside reverse transcriptase inhibitors (9 (75%)). Phylogenetic analysis revealed that 12 patients who failed treatment were infected with CRF35_AD.

CONCLUSION

Our study provides important insights into the characteristics and development of drug resistance in HIV-1-infected individuals receiving long-term antiretroviral therapy in Iran. The findings underline the need for regular viral load monitoring, individualized treatment selection, and targeted interventions to optimize treatment outcomes and prevent the further spread of drug-resistant strains.

Virologic Response to Dolutegravir Plus Lamivudine in People With Suppressed Human Immunodeficiency Virus Type 1 and Historical M184V/I: A Systematic Literature Review and Meta-analysis

Background

To investigate the impact of the M184V/I mutation on virologic response to dolutegravir plus lamivudine (DTG + 3TC) in suppressed-switch populations, a meta-analysis was performed using virologic outcomes from people with human immunodeficiency virus type 1 (PWH) with and without M184V/I before DTG + 3TC switch in real-world studies identified via systematic literature review. Sensitivity analyses were performed using data from PWH with M184V/I in interventional studies identified via targeted literature review.

Methods

Single-arm meta-analyses using common- and random-effects models were used to estimate proportions of PWH with virologic failure (VF) among real-world populations with and without M184V/I and interventional study participants with M184V/I at 24, 48, and 96 weeks.

Results

Literature reviews identified 5 real-world studies from 3907 publications and 51 abstracts meeting inclusion criteria and 5 interventional studies from 1789 publications and 3 abstracts. All time points had low VF incidence in PWH with M184V/I (real-world: 1.43%-3.81%; interventional: 0.00%) and without (real-world: 0.73%-2.37%). Meta-analysis-estimated proportions (95% confidence interval) with VF were low at weeks 24, 48, and 96, respectively, for PWH with M184V/I (real-world: 0.01 [.00-.04], 0.03 [.01-.06], and 0.04 [.01-.07]; interventional: 0.00 [.00-.02], 0.00 [.00-.01], and 0.00 [.00-.03]) and without (real-world: 0.00 [.00-.02], 0.02 [.01-.04], and 0.02 [.00-.05]). One real-world study (n = 712) reported treatment-emergent M184V at VF in 1 of 652 (0.15%) PWH without prior M184V/I.

Conclusions

Results suggest that prior M184V/I has minimal impact on virologic suppression after switching to DTG + 3TC and provide reassurance when considering switching regimens in virologically suppressed PWH with incomplete treatment history or limited treatment options.

Brief Report: Comparative Analysis of Pre-existing HIV Drug Resistance Mutations in Proviral DNA Using Next-Generation Sequencing and Routine HIV RNA Genotyping

BACKGROUND

We investigated whether deep sequencing of archived HIV DNA of antiretroviral-naive persons with acute/early HIV infection could identify transmitted drug resistance mutations (DRM), per the IAS drug resistance algorithm, which are not detected by routine bulk (consensus) sequencing.

METHODS

Deep sequencing of HIV DNA from peripheral blood mononuclear cells and consensus sequencing from concurrent blood plasma (BP) was performed from antiretroviral (ART)-naive adults with recent infection. We compared the prevalence of low-frequency (2%-20%) and high-frequency (>20%) nonnucleoside reverse transcriptase inhibitor (NNRTI), nucleoside reverse transcriptase inhibitor (NRTI), and protease inhibitor (PI) DRM.

RESULTS

Overall, 190 individuals were included, 72 (37.9%) with acute, 20 (10.5%) with very early, and 98 (51.6%) with recent HIV infection. Although all DRM detected in plasma appeared in archived proviral DNA, 9 high-frequency mutations were only detected in HIV DNA. These included 3 NRTI mutations, 4 NNRTI mutations, 1 PI mutation, and 1 H221Y (associated rilpivirine resistance) mutation. When considering DRM <20%, 11 NNRTI, 7 NRTI, 6 PI, and 3 F227L (associated doravirine resistance) mutations were found exclusively in HIV DNA. Interestingly, although 2 high-frequency M184V appeared in both DNA and RNA, low-frequency M184I were exclusive to HIV DNA (n = 6). No participants experienced virologic failure after initiating ART during the median 25.39 ± 3.13 months of follow-up on treatment.

CONCLUSION

Although most high-frequency DRMs were consistently detected in HIV RNA and HIV DNA, the presence of low-frequency DRM in proviral DNA may be relevant for clinicians because these mutations could become dominant under drug selection pressure.

Efficacy and Safety of Two-Drug Regimens with Dolutegravir plus Rilpivirine or Lamivudine in HIV-1 Virologically Suppressed People Living with HIV

BACKGROUND

The high effectiveness and safety of the two-drug (2DRs) strategy using dolutegravir (DTG) plus lamivudine (3TC) have led to international guidelines recommending their use for treatment-naive HIV patients. In virologically suppressed patients, de-escalating from 3DRs to DTG plus either rilpivirine (RPV) or 3TC has shown high rates of virological suppression.

OBJECTIVES

This study aimed to compare the real-life data of two multicenter Spanish cohorts of PLWHIV treated with DTG plus 3TC (SPADE-3) or RPV (DORIPEX) as a switch strategy, not only in terms of virological suppression, safety, and durability but also in terms of immune restoration. The primary endpoint was the percentage of patients with virological suppression on DTG plus 3TC and DTG plus RPV at weeks 24 and 48. The secondary outcomes included the proportion of patients who experienced the protocol-defined loss of virological control by week 48; changes in immune status in terms of CD4+ and CD8+ T lymphocyte counts and the CD4+/CD8+ ratio; the rate, incidence, and reasons for discontinuation of treatment over the 48-week study period; and safety profiles at weeks 24 and 48.

METHODS

We conducted a retrospective, observational, multicenter study of 638 and 943 virologically suppressed HIV-1-infected patients in two cohorts who switched to 2DRs with DTG plus RPV or DTG plus 3TC.

RESULTS

The most frequent reasons for starting DTG-based 2DRs were treatment simplification/pill burden or drug decrease. The virological suppression rates were 96.9%, 97.4%, and 99.1% at weeks 24, 48, and 96, respectively. The proportion of patients with virological failure over the 48-week study period was 0.01%. Adverse drug reactions were uncommon. Patients treated with DTG+3TC increased CD4, CD8, and CD4/CD8 parameters at 24 and 48 weeks.

CONCLUSIONS

We conclude that DTG-based 2DRs (combined with 3TC or RPV) in clinical practice were effective and safe as a switching strategy, with a low VF and high viral suppression rates. Both regimens were well tolerated, and ADR rates were low, including neurotoxicity and induced treatment discontinuations.

A novel strategy against hepatitis B virus: Glycyrrhetnic acid conjugated multi-component synergistic nano-drug delivery system for targeted therapy

It is well known that Glycyrrhetnic acid (GA) has significant liver-targeting and anti-inflammatory effects. Syringopicroside (SYR) and Hydroxytyrosol (HT), the active components of the Chinese herb Syringa oblata Lindl, have earned great reputation for their potential in preventing or treating viral hepatitis type B. Therefore, we loaded SYR and HT into GA-conjugated PEG-PLGA, so that they could target the liver in additional to exerting their own pharmacological effects in a synergistic. However, the in vivo targeting and the low bioavailability of SYR and HT pose a huge challenge. Therefore, we synthesized GA-conjugated multi-component nano-drug delivery system (SH-GPP). SH-GPP had a regular spherical shape with a uniform size distribution of 110.5 ± 3.18 nm. We further evaluated the effects of SH-GPP in vitro and in vivo. In the in vivo experiment, we evaluated the following parameters: the serum ALT and AST values; liver tissue homogenate MDA and SOD; HE staining of the pathological liver sections; and the liver coefficient. In the in vitro studies, the following parameters were evaluated: cellular uptake of SH-GPP; wound healing/scratch assay; cellular apoptosis; cell cycle; HBsAg; and HBeAg content. SH-GPP had better anti-hepatitis B effect than Syringopicroside and hydroxytyrosol (SH) and NPP alone. The targeting ability of GA enabled HT and SYR in GPP to reach the liver accurately, and played a synergistic role to maximize their therapeutic effects. This study provides a novel strategy against hepatitis B virus, and also provides a feasible scheme for improving the low bioavailability of the active components of traditional Chinese medicine.

HIV-1 resistance against dolutegravir fluctuates rapidly alongside erratic treatment adherence: a case report

OBJECTIVES

We report a case of incomplete HIV-1 suppression on a dolutegravir, lamivudine, and abacavir single-tablet regimen with the emergence of the H51Y and G118R integrase resistance mutations.

METHODS

Integrase sequencing was performed retrospectively by Sanger and next-generation sequencing. Rates of emergence and decline of resistance mutations were calculated using next-generation sequencing data. Dolutegravir plasma concentrations were measured by ultra-performance liquid chromatography-tandem mass spectrometry. The effects of H51Y and G118R on infectivity, fitness, and susceptibility to dolutegravir were quantified using cell-based assays.

RESULTS

During periods of non-adherence to treatment, mutations were retrospectively documented only by next-generation sequencing. Misdiagnosis by Sanger sequencing was caused by the rapid decline of mutant strains within the retroviral population. This observation was also true for a M184V lamivudine-resistant reverse transcriptase mutation found in association with integrase mutations on single HIV genomes. Resistance rebound upon treatment re-initiation was swift (>8000 copies per day). Next-generation sequencing indicated cumulative adherence to treatment. Compared to WT HIV-1, relative infectivity was 73%, 38%, and 43%; relative fitness was 100%, 35%, and 10% for H51Y, G118R, and H51Y+G118R viruses, respectively. H51Y did not change the susceptibility to dolutegravir, but G188R and H51Y+G118R conferred 7- and 28-fold resistance, respectively.

CONCLUSION

This case illustrates how poorly-fit drug-resistant viruses wax and wane alongside erratic treatment adherence and are easily misdiagnosed by Sanger sequencing. We recommend next-generation sequencing to improve the clinical management of incomplete virological suppression with dolutegravir.

High efficacy of switching to bictegravir/emtricitabine/tenofovir alafenamide in people with suppressed HIV and preexisting M184V/I

OBJECTIVE

We investigated the prevalence of preexisting M184V/I and associated risk factors among clinical trial participants with suppressed HIV and evaluated the impact of M184V/I on virologic response after switching to bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF).

DESIGN

Participant data were pooled from six clinical trials investigating the safety and efficacy of switching to B/F/TAF in virologically suppressed people with HIV.

METHODS

Preexisting drug resistance was assessed by historical genotypes and/or baseline proviral DNA genotyping. Virologic outcomes were determined by last available on-treatment HIV-1 RNA. Stepwise selection identified potential risk factors for M184V/I in a multivariate logistic regression model.

RESULTS

Altogether, 2034 participants switched treatment regimens to B/F/TAF and had follow-up HIV-1 RNA data, and 1825 of these participants had baseline genotypic data available. Preexisting M184V/I was identified in 182 (10%), mostly by baseline proviral DNA genotype ( n  = 167). Most substitutions were M184V ( n  = 161) or M184V/I mixtures ( n  = 10). Other resistance substitutions were often detected in addition to M184V/I ( n  = 147). At last on-treatment visit, 98% (179/182) with preexisting M184V/I and 99% (2012/2034) of all B/F/TAF-treated participants had HIV-1 RNA less than 50 copies/ml, with no treatment-emergent resistance to B/F/TAF. Among adult participants, factors associated with preexisting M184V/I included other resistance, black race, Hispanic/Latinx ethnicity, lower baseline CD4 + cell count, advanced HIV disease, longer duration of antiretroviral therapy, and greater number of prior third agents.

CONCLUSION

M184V/I was detected in 10% of virologically suppressed clinical trial participants at study baseline. Switching to B/F/TAF demonstrated durable efficacy in maintaining viral suppression, including in those with preexisting M184V/I.

Impact of pre-existent drug resistance on virological efficacy of single tablet regimens in people living with HIV

Despite the broad use of single tablet regimens (STRs), few real-life data are available regarding the impact of pre-existent drug resistance on virological failure (VF). Through this study we aimed to fill this gap, by analyzing a large cohort of individuals selected from the ARCA database. The impact on VF of pre-existent resistance associated mutations (RAMs) and cumulative genotypic susceptibility score (cGSS) before STR start was evaluated through survival analysis. Potential emergence of resistance at VF was also evaluated. Overall, 3916 individuals were included: 678 treatment-naïve (G1), 2309 treatment-experienced aviremic (G2), and 929 viremic (G3); 65.2% of them was treated with an STR based on efavirenz (35.2%) or rilpivirine (30%). At two years after starting STR, the overall probability of VF was 5.9% in G1, 8.7% in G2, and 20.8% in G3. No impact of pre-existent resistance on VF was found in G1. The probability of VF was higher in patients with cGSS<3 (reduced susceptibility to at least one drug) than in those with cGSS=3 (full susceptibility to STR drugs) in both G2 and G3. A higher probability of VF was also found in presence of pre-existent M184V (alone or in combination with pre-existent thymidine analogue mutations). Among patients who failed STR, a significant emergence of RAMs was found only in those exposed to EFV/FTC/TDF in G3 (specifically K103N and M184V). Our results confirm a high efficacy of STRs in clinical settings. Pre-existent resistance seems to influence virological efficacy of STR in treatment-experienced individuals (both aviremic and viremic).

Low-level viremia and virologic failure among people living with HIV who received maintenance therapy with co-formulated bictegravir, emtricitabine and tenofovir alafenamide versus dolutegravir-based regimens

BACKGROUND

Real-world experience with low-level viremia (LLV) and its impact remain less reported among people living with HIV (PLWH) who receive antiretroviral therapy (ART) containing second-generation integrase strand transferase inhibitors (INSTIs), including dolutegravir and bictegravir.

METHODS

Virally suppressed PLWH who had achieved plasma HIV RNA load (PVL) <50 copies/mL for ≥6 months and were switched to either dolutegravir- or bictegravir-based ART were included in this retrospective cohort study. The incidence rates of developing LLV events (PVL, 50-199 copies/mL) and virologic failure (VF) (PVL ≥1000 copies/mL) were compared between the dolutegravir and bictegravir cohorts.

RESULTS

A total of 623 and 862 PLWH switched to dolutegravir-based and bictegravir-based ART, respectively, were included. The incidence rates of developing LLV were 6.2 per 100 person-years of follow-up (PYFU) in the bictegravir cohort and 3.8 per 100 PYFU in the dolutegravir cohort (incidence rate ratio [IRR], 1.63; 95% confidence interval [CI], 0.90-2.95, p=0.08), while the rates of VF were 0.69 per 100 PYFU and 0.95 per 100 PYFU, respectively, in the bictegravir and dolutegravir cohort (IRR, 0.72; 95% CI, 0.12-3.39, p=0.34). Presence of LLV events was not associated with subsequent VF in multivariate analysis. Secondary analysis also demonstrated that resistance-associated mutations (RAMs) to nucleoside reverse-transcriptase inhibitors before switch were not associated with adverse virologic outcomes in either cohort.

CONCLUSIONS

Among virally suppressed PLWH, the incidences of developing LLV or VF were similar after switch to dolutegravir- or bictegravir-based ART. Preexisting RAMs to nucleoside reverse-transcriptase inhibitors or the LLV events were not associated with subsequent VF.

Emergence of the G118R Pan-Integrase Resistance Mutation as a Result of Low Compliance to a Dolutegravir-Based cART

HIV-1 resistance towards integrase inhibitors is a potential threat of the success of HIV-1 combination treatment. G118R is a rare drug resistance mutation conferring pan-integrase resistance. Here, we describe the occurrence of G118R in a HIV-1 subtype-B-positive individual with major compliance problems, detected while the patient was on dolutegravir-based cART. We speculate the pre-selection of M184I/V aided the occurrence of G118R in this case, and discuss the robustness of dolutegravir-based therapies.

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.

Kinetics of archived M184V mutation in treatment-experienced virally suppressed HIV-infected patients

BACKGROUND

We aimed to assess the kinetics of drug-resistant viral variants (DRVs) harboring the M184V mutation in the proviral DNA of long-term virally suppressed patients, and factors associated with DRV persistence.

METHODS

HIV-DNA from blood cells stored in 2019 and 2016 was sequenced using both Sanger and ultradeep sequencing (SS and UDS, with a detection threshold of 1%) in ART-treated patients with HIV-RNA <50 copies/mL for at least 5 years, with past M184V mutation documented in HIV-RNA.

RESULTS

Among the 79 tested patients, by combining SS and UDS, the M184V was found to be absent in 26/79 (33%) patients (M184V- patients), and persisted in 53/79 (67%) (M184V+ patients). The M184V+ patients had a longer history of ART, a lower CD4 nadir and higher pretherapeutic HIV-RNA. Among the 37 patients with viral sequences assessed by UDS, the proportion of M184V+ DRVs significantly decreased between 2016 and 2019 (40% versus 14%, p=0.005). The persistence of M184V was associated with the duration and level of HIV-RNA replication under 3TC/FTC (p=0.0009 and p=0.009, respectively).

CONCLUSION

While it decreased over time in HIV-DNA, the M184V mutation was more frequently persistent in the HIV-DNA of more experienced patients with longer past replication under 3TC/FTC.

Deep sequencing analysis of M184V/I mutation at the switch and at the time of virological failure of boosted protease inhibitor plus lamivudine or boosted protease inhibitor maintenance strategy (substudy of the ANRS-MOBIDIP trial)

BACKGROUND

The ANRS12286/MOBIDIP trial showed that boosted protease inhibitor (bPI) plus lamivudine dual therapy was superior to bPI monotherapy as maintenance treatment in subjects with a history of M184V mutation.

OBJECTIVES

We aimed to deep analyse the detection of M184V/I variants at time of switch and at the time of virological failure (VF).

METHODS

Ultra-deep sequencing (UDS) was performed on proviral HIV-DNA at inclusion among 265 patients enrolled in the ANRS 12026/MOBIDIP trial, and on plasma from 31 patients experiencing VF. The proportion of M184V/I variants was described and the association between the M184V/I mutation at 1% of threshold and VF was explored with logistic regression models.

RESULTS

M184V and I mutations were detected in HIV-DNA for 173/252 (69%) and 31/252 (12%) of participants, respectively. Longer duration of first-line treatment, higher plasma viral load at first-line treatment failure and higher baseline HIV-DNA load were associated with the archived M184V. M184I mutation was always associated with a STOP codon, suggesting defective virus. The 48 week estimated probability of remaining free from VF was comparable with or without the M184V/I mutation for dual therapy. At failure, M184V and major PI mutations were detected in 1/17 and 5/15 patients in the bPI arm and in 2/2 and 0/3 in the bPI+lamivudine arm, respectively.

CONCLUSIONS

Using UDS evidenced that archiving of M184V in HIV-DNA is heterogeneous despite past historical M184V in 96% of cases. The antiviral efficacy of lamivudine-based dual therapy regimens is mainly due to the residual lamivudine activity.

Impact of archived M184V/I mutation on the effectiveness of switch to co-formulated elvitegravir, cobicistat, emtricitabine and tenofovir alafenamide among virally suppressed people living with HIV

OBJECTIVES

Real-world experience regarding the effectiveness of co-formulated elvitegravir, cobicistat, emtricitabine and tenofovir alafenamide (EVG/C/FTC/TAF) as a switch regimen is sparse among people living with HIV (PLWH) harbouring the M184V/I mutation with or without thymidine analogue-associated mutations (TAMs).

METHODS

In this retrospective multicentre study, PLWH who were switched to EVG/C/FTC/TAF after having achieved viral suppression (plasma HIV RNA <200 copies/mL) for 6 months or longer were included. Patients with archived M184V/I mutation (case patients) were matched to controls without M184V/I mutation at a 1:4 ratio. Patients with a history of virological failure or resistance to elvitegravir were excluded. The primary endpoint was virological non-success (plasma HIV RNA ≥50 copies/mL) at Week 48 of switch using a modified FDA snapshot analysis.

RESULTS

Overall, 100 case patients with the M184V/I mutation were identified, including 6 (6.0%) with K65R and 13 (13.0%) with at least one TAM, and were matched to 400 controls in terms of gender, age (mean = 40.3 versus 39.7 years) and cumulative exposure duration to tenofovir disoproxil fumarate (median = 146 versus 143 weeks). At Week 48, the rate of virological non-success for the case patients and controls was 5.0% (5/100) and 3.3% (13/400), respectively (difference = 1.7%; 95% CI = -2.9%-6.3%), while the rate of virological success was 88.0% and 89.5% for the case patients and controls, respectively. The presence of the K65R mutation or TAMs was not associated with virological non-response.

CONCLUSIONS

Among virally suppressed PLWH, EVG/C/FTC/TAF is effective in maintaining viral suppression at Week 48 despite archived M184V/I mutation with or without TAMs.

M184V/I does not impact the efficacy of abacavir/lamivudine/dolutegravir use as switch therapy in virologically suppressed patients

BACKGROUND

M184V/I NRTI resistance mutations can be selected by either lamivudine/emtricitabine or abacavir. There are controversies about the use of abacavir/lamivudine/dolutegravir combinations in HIV-1-infected treatment-experienced patients with a fully suppressed HIV viral load (VL) and harbouring M184V/I.

OBJECTIVES

We assessed the efficacy of abacavir/lamivudine/dolutegravir when used in HIV-infected pretreated patients with an undetectable VL who previously harboured M184V/I as a unique NRTI resistance mutation in a genotypic resistance test and had no resistance to integrase inhibitors.

PATIENTS AND METHODS

A total of 154 patients with a fully suppressed HIV-1 plasma VL (<50 copies/mL) treated with tenofovir disoproxil fumarate/emtricitabine/boosted PI or abacavir/lamivudine/boosted PI who switched to an abacavir/lamivudine/dolutegravir regimen and had M184V/I as a unique NRTI resistance mutation in their therapeutic history were retrospectively analysed up to 12 months after the switch to abacavir/lamivudine/dolutegravir. Assessment of residual viraemia was performed at Months 1, 3, 6 and 12. Plasma VL with undetectable HIV-1 RNA corresponded to an absence of residual viraemia.

RESULTS

During the 12 months of follow-up, three patients had a blip of VL (53, 62 and 106 copies/mL) at Month 3 followed by a subsequent VL <50 copies/mL. No patient harboured a virological failure during the follow-up. Moreover, there was no change in residual viraemia during the follow-up.

CONCLUSIONS

M184V/I as a unique NRTI resistance mutation, regardless of possible selection by regimens containing lamivudine/emtricitabine or abacavir, does not affect the virological response of well-controlled patients who switched to abacavir/lamivudine/dolutegravir for at least 12 months.

Switching to Elvitegravir/Cobicistat/Emtricitabine/Tenofovir Alafenamide in Adults With HIV and M184V/I Mutation

BACKGROUND

The ability of elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide (E/C/F/TAF) to maintain virologic suppression in participants with M184V and/or M184I resistance mutations from historical genotypic reports when switching from a tenofovir disoproxil fumarate-based or abacavir (ABC)-based regimen was investigated.

SETTING

Phase IIIb, 48-week, open-label, single-arm, multicenter, clinical trial (NCT02616029).

METHODS

Virologically suppressed adults with HIV and documented M184V/I on historical genotypic records switched to E/C/F/TAF from a tenofovir disoproxil fumarate-based or ABC-based regimen. The primary end point was HIV-1 RNA of <50 copies per milliliter at week 12 using pure virologic response (PVR). Secondary end points included HIV-1 RNA of <50 copies per milliliter at weeks 24/48 (PVR) and at weeks 12, 24, and 48 (Food and Drug Administration snapshot algorithm), and change in CD4+ count at weeks 12, 24, and 48.

RESULTS

M184V alone was reported in 82.8% of 64 participants; 9.4% and 7.8% had M184I and M184V/I, respectively, and 43.8% had archived M184V/I (baseline DNA). All (62/62 with available data, 100%, 95% confidence interval 94.2% to 100%) participants maintained PVR at weeks 12, 24, and 48. By Food and Drug Administration snapshot algorithm, one participant had HIV-1 RNA of ≥50 copies per milliliter (week 12); confirmatory HIV-1 RNA was <50 copies per milliliter. No significant changes were observed in CD4+ cell count. Drug-related adverse events (AEs) were reported by 10 (15.6%) participants. Six (9.4%) and 5 (7.8%) participants had grade 3-4 AEs or serious AEs, respectively (none drug related).

CONCLUSIONS

The presence of the resistance mutations M184V/I did not jeopardize the efficacy of switching to E/C/F/TAF in virologically suppressed adults. High rates of virologic suppression were maintained throughout 48 weeks of therapy and treatment was well tolerated.

Simulating HIV Breakthrough and Resistance Development During Variable Adherence to Antiretroviral Treatment

BACKGROUND

Barriers to lifelong HIV-1 suppression by antiretrovirals include poor adherence and drug resistance; regimens with higher tolerance to missed doses (forgiveness) would be beneficial to patients. To model short-term nonadherence, in vitro experiments monitoring viral breakthrough (VB) and resistance development were conducted.

METHODS

HIV breakthrough experiments simulated drug exposures at full adherence or suboptimal adherence to bictegravir+emtricitabine+tenofovir alafenamide (BIC+FTC+TAF) or dolutegravir + lamivudine (DTG+3TC). MT-2 cells were infected with wild-type or low frequency M184V HIV-1, exposed to drug combinations, monitored for VB, and rebound virus was deep sequenced. Drug concentrations were determined using human plasma-free adjusted clinical trough concentrations (Cmin), at simulated Cmin after missing 1 to 3 consecutive doses (Cmin - 1 or Cmin - 2, and Cmin - 3) based on drug or active metabolite half-lives.

RESULTS

Cultures infected with wild-type or low frequency M184V HIV-1 showed no VB with BIC+FTC+TAF at drug concentrations corresponding to Cmin, Cmin - 1, or Cmin - 2 but breakthrough did occur in 26 of 36 cultures at Cmin - 3, where the M184V variant emerged in one culture. Experiments using DTG + 3TC prevented most breakthrough at Cmin concentrations (9/60 had breakthrough) but showed more breakthroughs as drug concentrations decreased (up to 36/36) and variants associated with resistance to both drugs emerged in some cases.

CONCLUSIONS

These in vitro VB results suggest that the high potency, long half-lives, and antiviral synergy provided by the BIC/FTC/TAF triple therapy regimen may protect from viral rebound and resistance development after short-term lapses in drug adherence.

Effectiveness and safety of dolutegravir two-drug regimens in virologically suppressed people living with HIV: a systematic literature review and meta-analysis of real-world evidence

Objectives

Dolutegravir (DTG) is widely recommended within three‐drug regimens. However, similar efficacy and tolerability have also been achieved with DTG within two‐drug regimens in clinical trials. This study evaluated the real‐world effectiveness and discontinuations in people living with HIV‐1 (PLHIV) switching to DTG with lamivudine (3TC) or rilpivirine (RPV).

Methods

This was a one‐arm meta‐analysis utilizing data from a systematic literature review. Data from real‐world evidence studies of DTG + RPV and DTG + 3TC were extracted, pooled and analysed. The primary outcome was the proportion of patients with viral failure (VF; ≥ 50 copies/mL in two consecutive measurements and/or ≥ 1000 copies/mL in a single measurement) at week 48 (W48) and week 96 (W96). Other outcomes included virological suppression (VS; < 50 copies/mL) and discontinuations (W48 and W96). Estimates were calculated for VF, VS as per snapshot (VSS) and on treatment analysis (VSOT), and discontinuations.

Results

Pooled mean estimates of VF for DTG + 3TC and DTG + RPV were 0.8% [95% confidence interval (CI): 0.4–1.3] and 0.6% (95% CI: 0.0–1.6), respectively, at W48. VSS rate at W48 was 85.0% (95% CI: 82.3–87.5) for DTG + 3TC regimen and 92.4% (95% CI: 85.0–97.7) in the DTG + RPV regimen. The DTG + 3TC and DTG + RPV regimens led to discontinuations in 13.6% (95% CI: 11.1–16.2) and 7.2% (95% CI: 2.1–14.4) of patients, respectively, at W48. Similar results were observed at W96.

Conclusions

Treatment with DTG + 3TC or DTG + RPV in clinical practice provides a low rate of VF and a high rate of VS when initiated in virologically suppressed PLHIV with diverse backgrounds.

Impact of previous HIV resistance and virologic failures on virologic outcome following a switch to dolutegravir with 2 NRTIs among people living with HIV

There is uncertainty regarding the potential virologic outcome associated with a change in antiretroviral therapy (ARV) among PLHIV who had previous documented virologic failure or who have been exposure to mono/dual nucleoside reverse transcriptase inhibitors (NRTI) therapy. The objective was to measure the potential impact of exposure to previous virologic failure or mono/dual NRTI regimen on virologic outcome of PLHIV following a switch to dolutegravir with 2 NRTIs from a viremia suppressive ARV therapy.Data from the Quebec HIV Cohort including 10219 PLHIV were collected through routine clinical care at 4 clinical sites in Montreal, Canada. This study includes patients whose ARV therapy was switched to dolutegravir with 2 NRTIs since 2013 with undetectable viral load for ≥6 months before switch. The association between exposure and post-switch virologic outcome was measured by marginal hazard ratio estimated using the Inverse probability weighting Cox model.Among the 1199 eligible PLHIV, 478 (39.9%) previously experienced at least one virologic failure or were exposed to mono/dual therapy before dolutegravir switch. Post-switch virologic failure after 30 months occurred in 4.1% (95% CI 2.1-7.9) of exposed compared to 4.1% (95% CI 2.3-7.4) in unexposed participants. The adjusted hazard ratio for the association between exposure and post-switch virologic failure was 0.84 (95% CI 0.35-2.01).Our findings suggest that switch to dolutegravir with 2 NRTIs from a suppressive therapy is a safe option for PLHIV with documented virologic failure and/or previous exposure to mono/dual NRTI therapy.

Emergence of Resistance to Integrase Strand Transfer Inhibitors during Dolutegravir Containing Triple-Therapy in a Treatment-Experienced Patient with Pre-Existing M184V/I Mutation

With the current widespread use of dolutegravir in low-income countries, the understanding of the impact of nucleoside reverse transcriptase inhibitor (NRTI-) associated mutations on the efficacy of dolutegravir-containing antiretroviral therapy (ART) is of utmost importance. We describe a rare case of a patient with pre-existing M184V/I mutation and virological failure on a dolutegravir/lamivudine/abacavir regimen with the emergence of integrase strand transfer inhibitor resistance mutations. Additional risk factors, which may have triggered the virological failure, included suboptimal adherence and low nadir CD4+ cell count. This case illustrates that dolutegravir-containing triple-therapy should be prescribed with caution to patients with pre-existing M184V/I mutation and poor efficacy of the reverse transcriptase inhibitor backbone. In addition, this case highlights the need for viral load monitoring in patients on dolutegravir-containing regimens in settings with a high prevalence of the M184V/I mutation such as in low-income countries.

Antiretroviral Drugs for Treatment and Prevention of HIV Infection in Adults: 2020 Recommendations of the International Antiviral Society-USA Panel

Importance

Data on the use of antiretroviral drugs, including new drugs and formulations, for the treatment and prevention of HIV infection continue to guide optimal practices.

Objective

To evaluate new data and incorporate them into current recommendations for initiating HIV therapy, monitoring individuals starting on therapy, changing regimens, preventing HIV infection for those at risk, and special considerations for older people with HIV.

Evidence Review

New evidence was collected since the previous International Antiviral (formerly AIDS) Society-USA recommendations in 2018, including data published or presented at peer-reviewed scientific conferences through August 22, 2020. A volunteer panel of 15 experts in HIV research and patient care considered these data and updated previous recommendations.

Findings

From 5316 citations about antiretroviral drugs identified, 549 were included to form the evidence basis for these recommendations. Antiretroviral therapy is recommended as soon as possible for all individuals with HIV who have detectable viremia. Most patients can start with a 3-drug regimen or now a 2-drug regimen, which includes an integrase strand transfer inhibitor. Effective options are available for patients who may be pregnant, those who have specific clinical conditions, such as kidney, liver, or cardiovascular disease, those who have opportunistic diseases, or those who have health care access issues. Recommended for the first time, a long-acting antiretroviral regimen injected once every 4 weeks for treatment or every 8 weeks pending approval by regulatory bodies and availability. For individuals at risk for HIV, preexposure prophylaxis with an oral regimen is recommended or, pending approval by regulatory bodies and availability, with a long-acting injection given every 8 weeks. Monitoring before and during therapy for effectiveness and safety is recommended. Switching therapy for virological failure is relatively rare at this time, and the recommendations for switching therapies for convenience and for other reasons are included. With the survival benefits provided by therapy, recommendations are made for older individuals with HIV. The current coronavirus disease 2019 pandemic poses particular challenges for HIV research, care, and efforts to end the HIV epidemic.

Conclusion and Relevance

Advances in HIV prevention and management with antiretroviral drugs continue to improve clinical care and outcomes among individuals at risk for and with HIV.

Virologic suppression in patients with a documented M184V/I mutation based on the number of active agents in the antiretroviral regimen

Objectives:

The optimal antiretroviral therapy for patients with the M184V/I mutation is not known. The primary objective of this study was to determine the efficacy of various antiretroviral therapies in patients with HIV and the M184V/I mutation based on the number of active antiretroviral agents.

Methods:

A retrospective chart review was conducted of 100 treatment-experienced patients harboring the M184V/I mutation seen at an urban HIV clinic. Efficacy was classified as percentage of patients with viral suppression defined as HIV RNA viral load <200 copies/mL at last measurement on current antiretroviral therapy, stratified by the number of active antiretroviral agents.

Results:

The primary outcome of viral suppression occurred in 70.6% (12/17) of patients on <2 active agents, 77.2% (44/57) on 2–2.5 active agents, and 69.2% (18/26) on 3 active agents. No significant difference was found between viral suppression and patients on <2 and 2–2.5 antiretroviral agents (odds ratio = 0.71, 95% confidence interval = (0.21, 2.39), p = 0.8) or between patients on 3 and 2–2.5 active agents (odds ratio = 0.66, 95% confidence interval = (0.23, 1.88), p = 0.7). The most commonly prescribed regimen consisted of a boosted protease inhibitor with an integrase strand transfer inhibitor and two nucleoside reverse transcriptase inhibitors, one of which being lamivudine or emtricitabine.

Conclusion:

Similar rates of viral suppression were observed in patients regardless of the number of active antiretroviral agents prescribed. Regimens containing less than 3 active agents may maintain virologic suppression in patients with the M184V/I mutation. Further studies are needed to determine optimal antiretroviral therapy for patients with the M184V/I mutation.

Molecular genotypes of gag sequences in HIV-1 infected children treated with antiretroviral therapy in Vietnam

Background:

Gag protein of human immunodeficiency virus (HIV) has been reported to play a crucial role in establishing infection, viral replication, and disease progression; thus, gag might be related to treatment response. The objective of this study was to investigate molecular genotypes of the gag gene, particularly the important functional binding domains in relation to treatment outcomes.

Methods:

HIV-infected children enrolled and treated at Vietnam National Children’s Hospital were recruited in the study. A total of 25 gag sequences were generated and used to construct phylogenetic trees and aligned with a reference sequence comparing 17 functional domains.

Results:

We found that all patients in a treatment failure (TF) group belonged to one cluster of the phylogenetic tree. In addition, the rate of mutations was significantly higher in TF compared with a treatment success (TS) group, specifically the PIP2 recognition motif, and the nucleocapsid basic and zinc motif 2 domains [median and (interquartile range (IQR): 12.5 (6.25–12.5) versus 50 (25–50), p < 0.01; 0 (0–0) versus 0 (0–21.43), p = 0.03 and 0 (0–7.14) versus 7.14 (7.14–7.14), p = 0.04, respectively]. When analyzing gag sequences at different time points in seven patients, we did not observe a consistent mutation pattern related to treatment response.

Conclusion:

Gag mutations in certain domains might be associated with increased viral load; therefore, studying the molecular genotype of the gag gene might be beneficial in monitoring treatment response in HIV-infected children.

Antivirals Against Coronaviruses: Candidate Drugs for SARS-CoV-2 Treatment?

Coronaviruses (CoVs) are a group of viruses from the family Coronaviridae that can infect humans and animals, causing mild to severe diseases. The ongoing pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) represents a global threat, urging the development of new therapeutic strategies. Here we present a selection of relevant compounds that have been described from 2005 until now as having in vitro and/or in vivo antiviral activities against human and/or animal CoVs. We also present compounds that have reached clinical trials as well as further discussing the potentiality of other molecules for application in (re)emergent CoVs outbreaks. Finally, through rationalization of the data presented herein, we wish to encourage further research encompassing these compounds as potential SARS-CoV-2 drug candidates.