Development of enhanced HIV-1 non-nucleoside reverse transcriptase inhibitors with improved resistance and pharmacokinetic profiles

HIV-1 infection is a manageable chronic condition, with non-nucleoside HIV-1 reverse transcriptase inhibitors (NNRTIs) remaining a cornerstone of antiretroviral therapy. Nevertheless, drug resistance to existing therapeutics is a serious and immediate concern. Using structure-based and scaffold-hopping approaches, we designed evolved diarylpyrimidine analogs targeting reverse transcriptase (RT), exploiting chemical space surrounding the NNRTI-binding pocket. We identified compounds 5i3 and 5e2, with robust antiviral efficacy against wild-type HIV-1 and rilpivirine-resistant strains. Encouragingly, in vitro selection of mutant strains with 5i3 took 39 passages to select resistance, with no phenotypic cross-resistance observed with known RT drugs. Co-crystal structures of wild-type and mutant RT with 5i3 and 5e2 revealed their resilience toward resistance mutations due to enhanced conformational flexibility and positional adaptability. 5i3 exhibited good pharmacokinetic properties and favorable safety profiles, without substantial cytochrome P450 inhibition, and excellent oral bioavailability. These derivatives represent a promising scaffold for the development of anti-HIV drugs.

Efficacy, safety, and anti-inflammatory properties of the switch to a doravirine-based regimen among antiretroviral-experienced elderly people living with HIV-1: the DORAGE cohort

Doravirine (DOR) is a novel antiretroviral agent with a favorable resistance profile and high tolerability. However, evidence is limited on DOR among elderly people living with HIV (PLWH) and whether it might modulate chronic inflammation. We aimed to investigate the efficacy, safety, and tolerability of DOR as a switching strategy among elderly PLWH and its impact on chronic inflammation in a real-life setting. We recruited a cohort of ART-experienced PLWH undergoing a therapeutic switch to a DOR-based regimen under virologic control (defined as HIV-RNA <200 copies/mL), regardless of the previous ART regimen. The primary objective was the evaluation of the rate of virologic control at 48 weeks post-switch. Secondary objectives included analyzing immune and metabolic outcomes. Plasmatic hs-CRP, IL-6, and D-dimer levels were measured as chronic inflammation markers. Overall, 150 PLWH were screened, and 147 were enrolled into the study. A total of 134 PLWH completed the follow-up. The rate of virological control was 96.1% (122/134; CIs: 91.0%-98.7%) in the per-protocol analysis. After 48 weeks from the switch, we recorded significant reductions in serum fasting glycemia (P 0.019), triglycerides (P 0.024), and total cholesterol/HDL ratio (P 0.017); no clinically significant differences were detected in the body weight and BMI, as long as in immune, hepatic, and renal profiles. A significant reduction in IL-6 (P 0.019) and hs-CRP (P 0.019) was observed. DOR is an effective and safe treatment choice for elderly PLWH. The intriguing modulatory effect of DOR-based regimens on chronic systemic inflammation deserves further investigation.

Long-term effectiveness, safety, and tolerability of doravirine in antiretroviral-experienced people with HIV in real life

Real-life data on doravirine (DOR) in different drug combinations are limited. We evaluated the effectiveness of DOR plus two nucleos(t)ide reverse transcriptase inhibitors (NRTI), mainly abacavir/lamivudine, and dual therapies in people with HIV (PWH), mostly virologically suppressed. Ambispective observational study that enrolled adults PWH who initiated a DOR-based regimen from September 2020 to February 2022 at a referral center in Spain. Participants were grouped as follows: A, received DOR plus two NRTI; B, dual therapy (DT) with DOR plus dolutegravir (DTG) or darunavir/cobicistat (DRVc); C, DOR plus ≥two antiretroviral drugs. The primary endpoints were treatment effectiveness at week 48 by intention-to-treat (ITT) and per-protocol analysis (OT). A cohort of 187 participants, 91% virologically suppressed, were analyzed after a median follow-up of 112 weeks (80-136). Group A received DOR plus abacavir/lamivudine (ABV/3TC) (n = 109) or tenofovir/emtricitabine (TFV/3TC) (n = 45). At week 48, the effectiveness of DOR plus ABV/3TC by ITT was 90.8% (CI95, 88.0-93.6), better than with TFV/FTC [73.3% (66.7-79.9); P = 0.003]. Only one virologic failure was observed. Mild adverse effects were the cause of treatment discontinuation in 7.8%, followed by switching to a single-tablet regimen. In group B, the effectiveness by ITT was 92.9% (CI95, 88.0-97.8) at week 48. No adverse effects or virologic failure were registered in this group. DOR plus two NRTI or DT have long-term effectiveness and safety as a switching option for PWH, mostly virologically suppressed. The DOR plus ABV/3TC combination has shown even better effectiveness than TFV/FTC.IMPORTANCEDOR-based regimens have shown long-term effectiveness and safety in PWH, mostly virologically suppressed. The combination of DOR plus ABV/3TC has shown even better safety and effectiveness than TFV/FTC. DOR plus two NRTI offers cost benefits compared to other regimens.

Doravirine/Lamivudine/Tenofovir Disoproxil Fumarate for Nonoccupational HIV-1 Postexposure Prophylaxis: A Prospective Open-Label Trial (DORAVIPEP)

Background

New regimens may provide better tolerability, convenience, and safety for nonoccupational human immunodeficiency virus (HIV) postexposure prophylaxis (PEP). For this reason, we evaluated the single-tablet regimen of doravirine/lamivudine/tenofovir disoproxil fumarate (DOR/3TC/TDF) for 28 days.

Methods

This was a prospective, open-label, single-arm trial including individuals with potential HIV-1 exposure within 72 hours. The primary endpoint was noncompletion of PEP at day 28. Secondary endpoints were adverse effects, adherence, and rate of seroconversion. We performed follow-up at day 7, week 4, and week 12.

Results

Between September 2019 and March 2022, the study enrolled 399 individuals. Median age was 30 (interquartile range [IQR], 27-36) years, and 91% (n = 364) were male. The mode of exposure was sex between men in 84% (n = 331) of cases; risk assessment for HIV-1 transmission was considered as "high" in 97% (n = 385) of the participants. Median time from exposure to consultation was 24 (IQR, 13-40) hours. Noncompletion of PEP was 29% (n = 114) (95% confidence interval [CI], 24%-33%) and 20% (n = 72) (95% CI, 16%-25%) per modified intention-to-treat. Main reasons for noncompletion were loss to follow-up (n = 104 [91%]) and intolerance (n = 8 [7%]). Older age was associated with a lower risk of premature discontinuation (OR, 0.94; P < .001). One hundred twenty-three (31%) participants reported adverse events, mostly mild and self-limited (82%); discontinuation occurred in 8 cases (2%). Adherence to PEP in the assessed users was 96%. There were no HIV seroconversions.

Conclusions

DOR/3TC/TDF is a well-tolerated option for nonoccupational PEP. Clinical Trials Registration. NCT04233372.

Doravirine responses to HIV-1 viruses bearing mutations to NRTIs and NNRTIs under in vitro selective drug pressure

OBJECTIVES

The NNRTI doravirine has been recently approved for the first-line treatment of HIV-infected patients, eliciting favourable responses against viruses bearing the K103N, Y181C and G190A mutations. This study used in vitro drug selections to elaborate the breadth of doravirine responses against viruses bearing NNRTI and NRTI resistance-associated mutations (RAMs).

METHODS

WT clinical isolates (n = 6) and viruses harbouring common NRTI and NNRTI RAMs (n = 6) were serially passaged in escalating concentrations of doravirine, doravirine/islatravir, doravirine/lamivudine and rilpivirine over 24 weeks. Genotypic analysis ascertained the appearance and accumulation of NNRTI RAMs. Phenotypic drug susceptibility assays assessed resistance conferred by acquired NNRTI RAMs.

RESULTS

For WT viruses, doravirine pressure led to the appearance of V108I or V106A/I/M RAMs after 8 weeks, conferring low-level (∼2-fold) resistance. After 24 weeks, the accumulation of three to six secondary RAMs, including F227L, M230L, L234I and/or Y318, resulted in high-level (>100-fold) resistance to doravirine. Notably, viruses with these doravirine RAMs remained susceptible to rilpivirine and efavirenz. This contrasted with rilpivirine where acquisition of E138K, L100I and/or K101E resulted in >50-fold cross-resistance to all NNRTIs. Doravirine selection of viruses bearing common NRTI and NNRTI RAMs showed delayed acquisition of RAMs compared with WT virus. Pairing doravirine with islatravir or lamivudine attenuated the development of NNRTI RAMs.

CONCLUSIONS

Doravirine showed favourable resistance profiles against viruses harbouring NRTI and NNRTI RAMs. The high barrier to resistance to doravirine coupled with the long intracellular half-life of islatravir may provide the opportunity for long-acting treatment options.

Residual phenotypic susceptibility to doravirine in multidrug-resistant HIV-1 from subjects enrolled in the PRESTIGIO Registry

OBJECTIVES

Doravirine shows a rather distinct resistance profile within the nonnucleoside reverse transcriptase inhibitor (NNRTI) class. This study aimed to evaluate the phenotypic susceptibility to doravirine, rilpivirine and etravirine in a panel of multidrug-resistant (MDR) HIV-1 isolates collected from people living with HIV (PLWH) enrolled in the PRESTIGIO Registry.

METHODS

Recombinant viruses expressing PLWH-derived protease, reverse transcriptase coding regions were generated from plasma samples at virological failure with documented resistance to protease inhibitors, nucleoside reverse transcriptase inhibitors, NNRTIs and integrase strand transfer inhibitors. In vitro susceptibility was assessed through a phenotypic assay measuring fold-change values with respect to the reference NL4-3 virus. Genotypic susceptibility was computed by the Stanford HIVdb algorithm 8.9-1.

RESULTS

Plasma samples were collected from 22 PLWH: 20 (91%) were male, median age 55 years (IQR 50-58), time since HIV-1 diagnosis 27 years (23-31) and time on antiretroviral treatment 23 years (22-26). Median doravirine, etravirine and rilpivirine fold-change values were 9.8 (2.9-40.4), 42.9 (3.1-100.0) and 100.0 (17.9-100.0), respectively. According to the fold-change cut-offs, full susceptibility was observed in five (23%), four (18%) and one (5%) cases with doravirine, etravirine and rilpivirine, respectively. Irrespective of the presence of specific doravirine mutations, higher numbers of NNRTI mutations correlated with higher fold-change values for doravirine. By comparing the distribution of fold-change values with the Stanford HIVdb predicted susceptibility, a significant correlation was detected for doravirine and rilpivirine but not etravirine.

CONCLUSION

Despite extensive cross-resistance among NNRTIs, doravirine can be a valid option in a proportion of PLWH with MDR HIV-1. Doravirine activity appeared to be inferred with fair accuracy by the HIVdb algorithm.

Long-term follow-up of HIV-1 multi-drug-resistant treatment-experienced participants treated with etravirine, raltegravir and boosted darunavir: towards drug-reduced regimen? ANRS CO3 Aquitaine Cohort 2007-2018

OBJECTIVE

To assess the efficacy of raltegravir, etravirine and darunavir/ritonavir (TRIO regimen) in treatment-experienced patients with human immunodeficiency virus-1 (HIV-1) infection by describing the proportion of patients who experienced virological failure (VF) at Week 24. The secondary objectives were to assess the HIV-1 plasma viral load (pVL) after Week 24, the proportion of patients who were receiving dual therapy or monotherapy at the last visit, and the number of deaths.

METHODS

Patients from the ANRS CO3 Aquitaine Cohort who were prescribed the TRIO regimen between February 2007 and September 2018 were classified into two groups based on their pVL at study inclusion: the virological failure group (VFG; pVL >50 copies/mL) and the virologically suppressed group (VSG; pVL <50 copies/mL). The impact of baseline pVL and genotypic susceptibility score (GSS) on VF was analysed.

RESULTS

In total, 184 patients were enrolled in this study, with 123 (66.8%) in the VFG and 61 (33.2%) in the VSG. The median length of follow-up was 7.5 (interquartile range 4.1-9.6) years, and 29 (15.8%) patients died. Thirty-seven (25.5%) patients experienced VF at Week 24, including 32/145 (32.7%) in the VFG and 5/47 (10.6%) in the VSG (P<0.01). Resistance-associated mutations were detected in integrase, reverse transcriptase and protease for 7/37 (18.9%), 3/37 (8.1%) and 1/37 (2.7%) patients, respectively. High pVL and GSS at baseline were independently associated with VF. At the last visit, 76/184 (41.3%) patients were still receiving the TRIO regimen, while 55/184 (29.9%) were receiving dual therapy and 1/184 (0.5%) was receiving protease inhibitor monotherapy. Among the 56 patients receiving dual therapy or monotherapy, 51 (96.2%) had pVL <50 copies/mL.

CONCLUSION

Despite a high level of mutation resistance at baseline, long-term virological follow-up was favourable and one-third of patients were eligible for drug-reducing strategies.

Doravirine-associated resistance mutations in antiretroviral therapy naïve and experienced adults with HIV-1 subtype C infection in Botswana

OBJECTIVES

There are limited data on the prevalence of doravirine (DOR)-associated drug resistance mutations in people with HIV (PWH) in Botswana. This cross-sectional, retrospective study aimed to explore the prevalence of DOR-associated resistance mutations among ART-naïve and -experienced PWH in Botswana enrolled in the population-based Botswana Combination Prevention Project (BCPP).

METHODS

A total of 6078 HIV-1C pol sequences were analysed for DOR-associated resistance mutations using the Stanford HIV drug resistance database, and their levels were predicted according to the Stanford DRM penalty scores and resistance interpretation. Virologic failure was defined as HIV-1 RNA load (VL) >400 copies/mL.

RESULTS

Among 6078 PWH, 5999 (99%) had known ART status, and 4529/5999 (79%) were on ART at time of sampling. The suppression rate among ART-experienced was 4517/4729 (96%). The overall prevalence of any DOR-associated resistance mutations was 181/1473 (12.3% [95% confidence interval {CI}: 10.7-14.1]); by ART status: 42/212 (19.8% [95% CI: 14.7-25.4]) among ART-failing individuals (VL ≥400 copies/mL) and 139/1261 (11.0% [95% CI: 9.3-12.9]) among ART-naïve individuals (P < 0.01). Intermediate DOR-associated resistance mutations were observed in 106/1261 (7.8% [95% CI: 6.9-10.1]) in ART-naïve individuals and 29/212 (13.7% [95% CI: 9.4-8.5]) among ART-experienced participants (P < 0.01). High-level DOR-associated resistance mutations were observed in 33/1261 (2.6% [95% CI: 1.8-3.7]) among ART-naïve and 13/212 (6.1% [95% CI: 3.6-10.8]) among ART-failing PWH (P < 0.01). PWH failing ART with at least one EFV/NVP-associated resistance mutation had high prevalence 13/67 (19.4%) of high-level DOR-associated resistance mutations.

CONCLUSION

DOR-associated mutations were rare (11.0%) among ART-naive PWH but present in 62.7% of Botswana individuals who failed NNRTI-based ART with at least one EFV/NVP-associated resistance mutation. Testing for HIV drug resistance should underpin the use of DOR in PWH who have taken first-generation NNRTIs.

ViMRT: a text-mining tool and search engine for automated virus mutation recognition

MOTIVATION

Virus mutation is one of the most important research issues which plays a critical role in disease progression and has prompted substantial scientific publications. Mutation extraction from published literature has become an increasingly important task, benefiting many downstream applications such as vaccine design and drug usage. However, most existing approaches have low performances in extracting virus mutation due to both lack of precise virus mutation information and their development based on human gene mutations.

RESULTS

We developed ViMRT, a text-mining tool and search engine for automated virus mutation recognition using natural language processing. ViMRT mainly developed 8 optimized rules and 12 regular expressions based on a development dataset comprising 830 papers of 5 human severe disease-related viruses. It achieved higher performance than other tools in a test dataset (1662 papers, 99.17% in F1-score) and has been applied well to two other viruses, influenza virus and severe acute respiratory syndrome coronavirus-2 (212 papers, 96.99% in F1-score). These results indicate that ViMRT is a high-performance method for the extraction of virus mutation from the biomedical literature. Besides, we present a search engine for researchers to quickly find and accurately search virus mutation-related information including virus genes and related diseases.

AVAILABILITY AND IMPLEMENTATION

ViMRT software is freely available at http://bmtongji.cn:1225/mutation/index.

High Prevalence of Doravirine Resistance in HIV-1-Infected Patients with Virological Failure to an NNRTI-Based Single-Tablet Regimen

Purpose

This study aimed to investigate the prevalence of resistance to a non-nucleoside reverse transcriptase inhibitor (NNRTI)-based single-tablet regimen (STR) in Taiwanese patients and clarify the clinical implications of using doravirine in patients who fail NNRTI treatment.

Patients and Methods

Taiwanese patients infected with HIV-1 who failed NNRTI-based STR treatment were enrolled in this retrospective cohort study from 2015 to 2020. Mutations associated with drug resistance were identified using the 2019 International Antiviral Society-USA list of drug-resistant mutations in HIV, and drug susceptibility was assessed according to the Stanford HIV Drug Resistance Database version 9. Median values of continuous variables were compared between two groups using the Mann-Whitney U-test, and categorical variables were compared using the chi-square test or Fisher's exact test.

Results

A total of 107 patients were included, of whom 29 were treatment failure to the initial STRs, and 78 failed treatment after switching to an STR. Seventy-four patients failed treatment with TDF/FTC/EFV (Atripla), 30 with TDF/FTC/RPV (Complera) and 3 with TAF/FTC/RPV (Odefsey). The prevalence rates of resistance to nucleoside reverse transcriptase inhibitors (NRTIs), NNRTIs, protease inhibitors (PIs) and integrase strand transfer inhibitors (INSTIs) were 76%, 86%, 3% and 2%, respectively. Among the 29 patients failure to the initial STRs, 62% developed doravirine resistance, compared to 64% of the 78 the patients who failed treatment after switching to an STR. There were no significant differences in the prevalence of specific NNRTI or doravirine resistance-associated mutations between these two groups. The patients with K65R mutations were more likely to have NNRTI resistance (p = 0.037) and doravirine resistance (p < 0.001).

Conclusion

Our findings showed a high rate of doravirine cross-resistance in patients with NNRTI-based STR treatment failure. Doravirine should be used cautiously as a salvage regimen in patients who fail NNRTI treatment.

Single Oral Doses of MK-8507, a Novel Non-Nucleoside Reverse Transcriptase Inhibitor, Suppress HIV-1 RNA for a Week

BACKGROUND

MK-8507 is a novel HIV-1 non-nucleoside reverse transcriptase inhibitor being developed for treatment of HIV-1 infection. MK-8507 has high antiviral potency in vitro and pharmacokinetic (PK) properties that support once-weekly dosing.

SETTING

A phase 1, open-label, proof-of-concept study was conducted in treatment-naive adults with HIV-1 infection to assess monotherapy antiviral activity.

METHODS

In 3 sequential panels, participants aged 18-60 years with baseline plasma HIV-1 RNA ≥10,000 copies/mL and CD4+ T-cell count >200/mm3 received a single oral dose of 40, 80, or 600 mg MK-8507 in the fasted state. Participants were assessed for HIV-1 RNA for at least 7 days, PKs for 14 days, and safety and tolerability for 21 days postdose.

RESULTS

A total of 18 participants were enrolled (6 per panel). The mean 7-day postdose HIV-1 RNA reduction ranged from ∼1.2 to ∼1.5 log10 copies/mL across the doses assessed. One patient had a viral rebound associated with emergence of an F227C reverse transcriptase variant (per chain-termination method sequencing) 14 days postdose; this variant was found in a second participant by ultra-deep sequencing as an emerging minority variant. MK-8507 PKs were generally dose-proportional and similar to observations in participants without HIV-1 infection in prior studies; mean MK-8507 half life was 56-69 hours in this study. MK-8507 was generally well tolerated at all doses.

CONCLUSIONS

The robust antiviral activity, PK, and tolerability of MK-8507 support its continued development as part of a complete once weekly oral regimen for HIV-1 treatment; combination therapy could mitigate the emergence of resistance-associated variants.

Doravirine: its role in HIV treatment

PURPOSE OF REVIEW

We reviewed evidence concerning the novel nonnucleoside reverse transcriptase inhibitor doravirine, aiming to identify situations where it may be selected in preference to integrase inhibitors.

RECENT FINDINGS

Doravirine is licenced for the treatment of HIV-1 in North America and Europe. In two multicentre randomized controlled trials, noninferiority with comparator drugs efavirenz and darunavir/ritonavir was observed at 96 weeks. Doravirine is associated with a lower incidence of neuropsychiatric side effects relative to efavirenz, and favourable lipid changes relative to darunavir over 96 weeks. A lower incidence of weight gain, relative to indirect comparisons with integrase inhibitors, was observed. Doravirine has a high genetic barrier to resistance with retained activity in the presence of single NNRTI mutations K103N, Y181C and G190A. Primary drug resistance is infrequent and may be higher in South Africa relative to European populations. Doravirine may be used in renal or hepatic impairment and has a low potential for drug-drug interactions.

SUMMARY

Doravirine is a well tolerated and effective agent in ART-naive patients. Direct comparison with integrase inhibitors, and evidence on the outcomes of treatment with doravirine in the presence of prior NNRTI experience are required to better elucidate which patients will benefit most from doravirine therapy.

Impact of HIV-1 Resistance-Associated Mutations on Susceptibility to Doravirine: Analysis of Real-World Clinical Isolates

Clinical management of human immunodeficiency virus type-1 (HIV-1) infection may be negatively impacted by either acquired or transmitted drug resistance. Here, we aim to extend our understanding of the impact of resistance-associated mutations (RAMs) on the susceptibility of clinical isolates to the nonnucleoside reverse transcriptase inhibitor (NNRTI) doravirine. Clinical isolates from people living with HIV-1 undergoing routine testing for susceptibility to doravirine and other approved NNRTIs (etravirine, rilpivirine, efavirenz, and nevirapine) were collected from August 2018 to August 2019. Susceptibility in the presence/absence of NNRTI and nucleos(t)ide reverse transcriptase inhibitor (NRTI) mutations was determined using cutoffs for relative fold change in inhibition (ratio of the 50% inhibitory concentration [IC₅₀] of patient virus compared with the IC₅₀ of a wild-type reference strain). Biological cutoffs of 3- to 15-fold change were investigated for doravirine, with preestablished cutoffs used for the other NNRTIs. Of 4,070 clinical isolates, 42.9% had ≥1 NNRTI RAM. More isolates were susceptible to doravirine (92.5-96.7%) than to etravirine (91.5%), rilpivirine (89.5%), efavirenz (81.5%), or nevirapine (77.5%). Based on a 3-fold cutoff, doravirine susceptibility was retained in 44.7-65.8% of isolates resistant to another NNRTI and 28.5% of isolates resistant to all other tested NNRTIs. The presence of NRTI RAMs, including thymidine analog mutations, was associated with doravirine hypersusceptibility in some isolates, particularly in the absence of NNRTI RAMs. These results support the favorable resistance profile of doravirine and are of particular importance given the challenge posed by both acquired and transmitted resistance.

Low prevalence of doravirine-associated resistance mutations among polish human immunodeficiency-1 (HIV-1)–infected patients

Introduction

Doravirine (DOR) is a novel non-nucleoside reverse transcriptase inhibitor (NNRTI) that retains activity against common NNRTI resistance mutations. In this study, we aimed to investigate the prevalence of DOR resistance mutations compared with that of resistance mutations for other NNRTIs among HIV-1-infected treatment‐experienced and -naïve patients from Poland.

Methods

Resistance to DOR and other NNRTIs was assessed in two datasets: 1760 antiretroviral treatment-naïve HIV-1 patients and 200 treatment‐experienced patients. All 1960 sequences were derived from the patients using bulk sequencing. For resistance analyses, Stanford HIV drug resistance database scores were used.

Results

Overall, DOR resistance was present in 32 patients (1.62%), of whom 13 (0.74%) were naïve and 19 (9.50%) were treatment-experienced. The most common DOR resistance mutations observed among the naïve patients were A98G and K101E (0.2% each), and those among cART-experienced patients were L100I (2.0%), K101E, V108I, H221Y, and P225H (1.5% each). Furthermore, among the naïve patients, less common resistance to DOR (0.7%) compared with that to nevirapine (NVP) (2.1%; p = 0.0013) and rilpivirine (5.40%; p < 0.0001) was observed. For sequences obtained from treatment-experienced patients, the frequency of resistance to DOR (9.5%) was lower than that for efavirenz (25.5%; p < 0.0001) and NVP (26.0%; p < 0.0001).

Conclusions

The frequency of transmitted drug resistance to DOR is low, allowing for effective treatment of antiretroviral treatment-naïve patients and rapid treatment initiation. In cART-experienced patients, this agent remains an attractive NNRTI option with a higher genetic barrier to resistance.

Cell culture selections reveal favourable drug resistance profiles for doravirine and islatravir

BACKGROUND

The newer generation NNRTIs, including doravirine and rilpivirine, were designed to show high potency and overcome K103N, Y181C and G190A resistance.

OBJECTIVES

To assess emergent resistance to doravirine and rilpivirine, alone and paired with lamivudine or islatravir through in vitro drug selections.

METHODS

Subtype B (n = 3), non-B subtype (n = 3), and pNL4.3 viral isolates were passaged in cord blood mononuclear cells with progressively increasing concentrations of drug(s). Genotypic analysis compared the acquisition and accumulation of drug resistance mutations at weeks 8 and 24 following drug pressure. Cell-based phenotypic assays assessed cross-resistance patterns to NNRTIs by acquired resistance mutations.

RESULTS

Doravirine pressure resulted in the acquisition of V108I (6/7) and V106A/I/M (5/7) mutations at weeks 8, followed by F227L (4/7), Y318F (4/7), M230L (2/7) or L234I (2/7) by weeks 24. In contrast, rilpivirine resulted in E138K (5/7) followed by L100I (3/7), K101E (1/7), or M230L (1/7). Doravirine resistance pathways retained susceptibility to rilpivirine, whereas rilpivirine resistance conferred intermediate resistance (12-152-fold) to doravirine. Dual selections with islatravir or lamivudine delayed and diminished emergent resistance to doravirine, resulting in V108I (9/15) with fewer or no other changes at weeks 24. There was a lesser delay in emergent resistance to rilpivirine when combined with islatravir or lamivudine. The M184V mutation did not arise in dual selections with islatravir or lamivudine.

CONCLUSIONS

Doravirine showed a more robust resistance profile compared with other NNRTIs. The long intracellular half-life of islatravir and delayed acquisition of resistance in dual selections provide an opportunity for long-acting treatment options.

In vitro cross-resistance to doravirine in a panel of HIV-1 clones harbouring multiple NNRTI resistance mutations

OBJECTIVES

Doravirine is a recently licensed HIV-1 NNRTI with improved efficacy, pharmacokinetics and safety profile compared with efavirenz and limited cross-resistance with rilpivirine and etravirine. In this in vitro study, cross-resistance to doravirine was analysed in a representative panel of NNRTI-resistant clones.

METHODS

In vitro phenotypic susceptibility to doravirine was assessed in 10 clinically derived infectious clones with intermediate- to high-level resistance to rilpivirine, etravirine, efavirenz and nevirapine, and in NL4-3 site-directed mutants harbouring K103N, Y181C, M230L or K103N/Y181C NNRTI mutations.

RESULTS

Although none of the infectious clones harboured any of the major doravirine resistance-associated mutations (RAMs) included in the IAS-USA reference list, doravirine fold change (FC) values were comparable to or higher than those calculated for other NNRTIs, particularly etravirine and rilpivirine. As expected, single NNRTI mutations K103N and Y181C did not impair doravirine susceptibility (FC 1.4 and 1.8, respectively), while reduced activity was observed with the single M230L or double K103N/Y181C mutations (FC 7.6 and 4.9, respectively). Median FC values increased significantly with increasing numbers of NNRTI RAMs (P = 0.005) and were >10 in 4/4 and 1/4 clones harbouring four and three NNRTI RAMs, respectively. FC values correlated well with predicted susceptibility as inferred by Stanford HIV Drug Resistance Database (HIVdb) and ANRS algorithms (both P < 0.001).

CONCLUSIONS

Substantial cross-resistance to doravirine was detected in NNRTI-resistant viruses harbouring complex mutational patterns, even in the absence of major IAS-USA doravirine RAMs. Therefore, based on the simple IAS-USA reference list, doravirine resistance may be underestimated in viruses harbouring multiple NNRTI mutations.

Transmitted HIV drug resistance and subtype patterns among blood donors in Poland

Surveillance on the HIV molecular variability, risk of drug resistance transmission and evolution of novel viral variants among blood donors remains an understudied aspect of hemovigilance. This nationwide study analyses patterns of HIV diversity and transmitted resistance mutations. Study included 185 samples from the first time and repeat blood donors with HIV infection identified by molecular assay. HIV protease, reverse transcriptase and integrase were sequenced using population methods. Drug resistance mutation (DRM) patterns were analyzed based on the Stanford Interpretation Algorithm and standardized lists of transmitted mutations. Phylogeny was used to investigate subtyping, clustering and recombination patterns. HIV-1 subtype B (89.2%) followed by subtype A6 (7.6%) were predominant, while in three (1.6%) cases, novel recombinant B/A6 variants were identified. Non-B variants were more common among repeat donors (14.5%) compared to the first time ones (1.8%), p = 0.011, with higher frequency (9.9%) of A6 variant in the repeat donor group, p = 0.04. Major NRTI DRMs were observed in 3.8%, NNRTI and PI in 0.6% and INSTI 1.1% of cases. Additionally, E157Q polymorphism was observed in 9.8% and L74I in 11.5% of integrase sequences. Transmission of drug resistance among blood donors remains infrequent. Subtype patters increase in complexity with emergence of novel intersubtype A6B recombinants.

Is there a role for doravirine in African HIV treatment programmes? A large observational resistance study in South Africa

INTRODUCTION

Dolutegravir has replaced efavirenz in most low- and middle-income countries, due to better tolerability and formidable resistance profile, but dolutegravir side effects suggest alternatives are needed. We evaluated doravirine resistance in South Africa as a first step to assess whether doravirine may replace dolutegravir.

METHODS

A retrospective dataset was analysed for predicted doravirine susceptibility, including sequences obtained from three patient groups. First, data from 277 patients initiating antiretroviral treatment (ART) were collected between February 2013 and October 2014 as part of a national survey. Second, data from 788 patients experiencing NNRTI-based ART failure were obtained between February 2013 and October 2014 as part of a national survey. Third, data derived from 584 patients who had genotypic drug resistance testing requested after NNRT-based failure as part of individual patient management between January 2016 and December 2019. Pol sequences were generated using validated population-based in-house genotyping and submitted to Stanford HIVdb v8.9.

RESULTS AND DISCUSSION

Less than 5% of patients initiating ART presented with genotypic doravirine resistance, whereas most patients experiencing NNRTI-based ART failure presented with predicted intermediate (41.0%) or high-level resistance (43.8%) to doravirine. High-level resistance to doravirine was commonly predicted by the presence of at least three DRMs (79.7%). The predicted resistance profile to doravirine in ART-naïve patients is promising, but less so in those experiencing failure to first-generation NNRTIs. Accumulation of NNRTI DRMs seems to be an important factor in the poor resistance prediction for doravirine.

CONCLUSIONS

Although doravirine is approved as initial therapy in patients who are ART-naïve, it is currently recommended to obtain a genotype prior to the initiation of ART. Clinical studies are needed to ascertain whether predicted resistance profiles in ART naïve and NNRTI-treated patients translate into poor clinical outcomes, especially in settings where genotypic resistance testing is not available.

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.

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.

Doravirine and Its Potential in the Treatment of HIV: An Evidence-Based Review of the Emerging Data

The utility of doravirine in the management of HIV-1 infection is approved for use in patients who are antiretroviral-naïve as well as patients who have achieved stable virologic suppression and are interested in replacing their current antiretroviral therapy. The role of doravirine continues to evolve as data emerges on the potential for new combination therapy with the investigational agent, islatravir, as well as a potential strategy to minimize post-marketing safety concerns with recommended first-line agents, such as integrase inhibitors. The goal of this review is to assess recent and emerging data on the non-nucleoside reverse transcriptase inhibitor, doravirine.