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

Outcomes of switching from protease inhibitor-based antiretroviral therapy to bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) in virologically suppressed adults with nucleos(t)ide analogue resistance- a phase IV randomised, open-label study (PIBIK study)

BACKGROUND

There are limited data on how historical nucleoside reverse transcriptase inhibitor (NRTI) resistance-associated mutations (RAMs) other than M184V/I, affect the activity of B/F/TAF. We evaluated the outcomes of switching virologically suppressed (HIV-1 RNA < 50 copies/mL) individuals harbouring major RAMs from boosted protease inhibitor (bPI)-based therapy to B/F/TAF.

METHODS

Participants had various historical genotypic patterns including M184V/I, ≤2 thymidine analogue mutations (TAMs), and other NRTI RAMs (NAMs), and no integrase resistance. Baseline RAMs were explored by retrospective sequencing of cellular HIV-1 DNA. Participants were randomised (1:1) to switching to B/F/TAF either immediately or after 24 weeks. The primary outcome was the proportion of participants maintaining virological suppression (pure virologic response) at week-24; secondary outcomes were proportion of participants with virological suppression at week-48, pre-specified safety measures, and treatment-emergent resistance.

RESULTS

Historically, 21/72 (29.2%) participants had M184V/I, 5 (6.9%) M184V/I + 1 NAM, 31 (43.1%) 1 TAM ± M184V/I ± 1 NAM, and 15 (20.8%) 2 TAMs ± M184V/I ± 1 NAM. At week-24, proportions maintaining virological suppression were 33/33 (100%) on B/F/TAF vs. 38/39 (97.4%) on bPI (difference 2.6%; 95% CI -2.4%, 7.5%). Drug-related adverse events (AEs) were reported in 10/33 (30.3%) vs. 1/39 (2.6%), respectively. The immediate switch arm had improved lipid parameters but increased HbA1c and weight. Virological suppression was maintained at week-48. There were six discontinuations; four on B/F/TAF were drug-related and the two on bPI were not drug-related.

CONCLUSIONS

Historical NRTI resistance did not compromise the effectiveness of B/F/TAF in virologically suppressed adults. 12% experienced treatment-limiting AEs after switching.

REGISTRATION

EudraCT no: 2018-004732-30.

Current drugs for HIV-1: from challenges to potential in HIV/AIDS

The human immunodeficiency virus (HIV) persists in latently infected CD4+T cells and integrates with the host genome until cell death. Acquired immunodeficiency syndrome (AIDS) is associated with HIV-1. Possibly, treating HIV/AIDS is an essential but challenging clinical goal. This review provides a detailed account of the types and mechanisms of monotherapy and combination therapy against HIV-1 and describes nanoparticle and hydrogel delivery systems. In particular, the recently developed capsid inhibitor (Lenacapavir) and the Ainuovirine/tenofovir disoproxil fumarate/lamivudine combination (ACC008) are described. It is interestingly to note that the lack of the multipass transmembrane proteins serine incorporator 3 (SERINC3) and the multipass transmembrane proteins serine incorporator 5 (SERINC5) may be one of the reasons for the enhanced infectivity of HIV-1. This discovery of SERINC3 and SERINC5 provides new ideas for HIV-1 medication development. Therefore, we believe that in treating AIDS, antiviral medications should be rationally selected for pre-exposure and post-exposure prophylaxis to avoid the emergence of drug resistance. Attention should be paid to the research and development of new drugs to predict HIV mutations as accurately as possible and to develop immune antibodies to provide multiple guarantees for the cure of AIDS.

Safety and efficacy of switching to elvitegravir, cobicistat, emtricitabine, tenofovir disoproxil fumarate in treatment-experienced people with HIV: a multicenter cohort study

OBJECTIVES

We assessed the virologic efficacy of switching to co-formulated elvitegravir, cobicistat, emtricitabine, tenofovir disoproxil fumarate (E/C/F/TDF) in patients with controlled HIV infection.

METHODS

We conducted a retrospective multicenter observational cohort study including adult patients with controlled HIV-1 infection on any stable antiretroviral (ART) regimen, who switched to E/C/F/TDF. Success was measured by the proportion of patients with plasma viral load < 50 copies/ml at W48 using the FDA snapshot algorithm. We also assessed risk factors associated with virological failure (VF).

RESULTS

382 patients with HIV RNA < 50 copies/mL who switched to E/C/F/TDF were included in the study. Most patients (69.9%) were male, with median age 44 years (IQR 38-51), who had been on ART for a median of 7 years (IQR 4-13). Median CD4 count was 614/mm³ and 24.6% of the patients had a history of previous virological failure. The reasons for switching were simplification (67.0%) and tolerance issues (22.0%). At week 48, 314 (82.0% [95% CI 78.4-86.0]) patients had HIV RNA < 50 copies/mL, 13 (3.5% [95% CI 3.64-8.41]) experienced virological failure. Genotype at failure was available in 6/13 patients with detection of resistance-associated mutations to integrase inhibitors and NRTIs in 5/6 (83.3%) patients. We found no predictive factor associated with virological failure except for a borderline significance with the duration of viral suppression before the switch. Tolerability of E/C/F/TDF was good with 23/382 (6.0%) patients experiencing mild adverse reactions.

CONCLUSION

In our cohort, switching well-suppressed patients to E/C/F/TDF resulted in few virologic failures and was well tolerated. However, resistance to integrase inhibitors emerged in patients with virological failure.

Genotypic Resistance Testing of HIV-1 DNA in Peripheral Blood Mononuclear Cells

HIV-1 DNA exists in nonintegrated linear and circular episomal forms and as integrated proviruses. In patients with plasma viremia, most peripheral blood mononuclear cell (PBMC) HIV-1 DNA consists of recently produced nonintegrated virus DNA while in patients with prolonged virological suppression (VS) on antiretroviral therapy (ART), most PBMC HIV-1 DNA consists of proviral DNA produced months to years earlier. Drug-resistance mutations (DRMs) in PBMCs are more likely to coexist with ancestral wild-type virus populations than they are in plasma, explaining why next-generation sequencing is particularly useful for the detection of PBMC-associated DRMs. In patients with ongoing high levels of active virus replication, the DRMs detected in PBMCs and in plasma are usually highly concordant. However, in patients with lower levels of virus replication, it may take several months for plasma virus DRMs to reach detectable levels in PBMCs. This time lag explains why, in patients with VS, PBMC genotypic resistance testing (GRT) is less sensitive than historical plasma virus GRT, if previous episodes of virological failure and emergent DRMs were either not prolonged or not associated with high levels of plasma viremia. Despite the increasing use of PBMC GRT in patients with VS, few studies have examined the predictive value of DRMs on the response to a simplified ART regimen. In this review, we summarize what is known about PBMC HIV-1 DNA dynamics, particularly in patients with suppressed plasma viremia, the methods used for PBMC HIV-1 GRT, and the scenarios in which PBMC GRT has been used clinically.

Detection of archived lamivudine-associated resistance mutations in virologically suppressed, lamivudine-experienced HIV-infected adults by different genotyping techniques (GEN-PRO study)

BACKGROUND

Previously selected lamivudine resistance-associated mutations (RAMs) may remain archived within the proviral HIV-DNA.

OBJECTIVES

To evaluate the ability of proviral DNA genotyping to detect lamivudine RAMs in HIV-1 virologically suppressed participants; the correlation between Sanger and next generation sequencing (NGS); and predictive factors for detection of lamivudine RAMs in proviral DNA.

METHODS

Cross-sectional study of participants on stable antiretroviral therapy and suppressed for ≥1 year. Analysis of proviral DNA was performed by Sanger sequencing in whole blood and by NGS in PBMCs.

RESULTS

We analysed samples from 102 subjects (52 with and 50 without lamivudine RAMs in historical plasma RNA-genotypes). Among participants with previous lamivudine resistance, Sanger sequencing detected RAMs in 26.9%. Detection rates significantly increased using NGS: 47.9%, 64.6%, 75% and 87.5% with the 20%, 10%, 5% and 1% thresholds, respectively. As for participants without historical lamivudine resistance, Sanger detected the RAMs in 1/49 (2%), and NGS (5% threshold) in 8/45 (17.8%). Multivariate models fitted to the whole population revealed that having a history of lamivudine resistance was a risk factor for detection of lamivudine RAMs by NGS. Among participants with historical lamivudine resistance, multivariate analysis showed that a longer time since HIV diagnosis was associated with persistence of archived mutations by NGS at thresholds of >10% [OR 1.10 (95% CI: 1.00-1.24)] and >5% [OR 1.16 (95% CI: 1.02-1.32)].

CONCLUSIONS

Proviral DNA Sanger sequencing does not detect the majority of historical lamivudine RAMs. NGS increases the sensitivity of detection at lower thresholds, although the relevance of these minority populations with lamivudine RAMs needs further evaluation.