Immunological and virological consequences of patient-directed antiretroviral therapy interruption during chronic HIV-1 infection

Determinants of virological failure among patients on first line highly active antiretroviral therapy (HAART) in Southwest Ethiopia: A case-control study

Background

Virological failure remains a public health concern among patients with human immunodeficiency virus (HIV) after treatment initiation. Ethiopia is one of the countries that aims to achieve the global target of 90-90-90 that aims to achieve 90% virological suppression, but there is a paucity of evidence on the determinants of virological failure. Therefore, the study is intended to assess determinants of virological treatment failure among patients on first-line highly active antiretroviral therapy (HAART) at Mizan Tepi University Teaching Hospital (MTUTH), Southwest Ethiopia.

Method

A hospital-based unmatched case-control study was conducted from 11 November to 23 December 2020, among 146 cases and 146 controls. All cases and controls were selected randomly using computer-generated random numbers based on their medical record numbers. During the document review, data were collected using checklists, entered into Epi-data version 4.0.2, and analyzed by SPSS version 25. A multivariable logistic regression analysis was done to identify the independent determinants of virological treatment failure.

Results

In this study, being male (adjusted odds ratio (AOR) = 1.89, 95% CI: 1.04, 3.47), substance use (AOR = 2.67, 95% CI: 1.40, 4.95), baseline hemoglobin (Hgb) < 12 mg/dl (AOR = 3.22, 95% CI: 1.82, 5.99), poor drug adherence (AOR = 3.84, 95% CI: 1.77, 5.95), restart ART medication (AOR = 2.45, 95% CI: 1.69, 7.35), and opportunistic infection (OI) while on HAART (AOR = 4.73, 95% CI: 1.76, 12.11) were determinants of virological treatment failure.

Conclusion

The study revealed that the sex of the patient, history of substance use, baseline Hgb < 12 mg/dl, poor drug adherence, restart after an interruption, and having OI through the follow-up period were determinants of virological failure. Therefore, program implementation should consider gender disparity while men are more prone to virological failure. It is also imperative to implement targeted interventions to improve drug adherence and interruption problems in follow-up care. Moreover, patients with opportunistic infections and restart HAART need special care and attention.

Multifarious immunotherapeutic approaches to cure HIV-1 infection

Immunotherapy in the context of treated HIV-1 infection aims to improve immune responses to achieve better control of the virus. To date, multifaceted immunotherapeutic approaches have been shown to reduce immune activation and increase CD4 T-lymphocyte counts, further to the effects of antiretroviral therapy alone, in addition to improving HIV-1-specific T-cell responses. While sterilizing cure of HIV-1 would involve elimination of all replication-competent virus, a functional cure in which the host has long-lasting control of viral replication may be more feasible. In this commentary, we discuss novel strategies aimed at targeting the latent viral reservoir with cure of HIV-1 infection being the ultimate goal, an achievement that would have considerable impact on worldwide HIV-1 infection.

Therapeutic immunisation plus cytokine and hormone therapy improves CD4 T-cell counts, restores anti-HIV-1 responses and reduces immune activation in treated chronic HIV-1 infection

BACKGROUND

This randomised, open label, phase I, immunotherapeutic study investigated the effects of interleukin (IL)-2, granulocyte-macrophage colony-stimulating factor (GM-CSF), recombinant human growth hormone (rhGH), and therapeutic immunisation (a Clade B DNA vaccine) on combination antiretroviral therapy (cART)-treated HIV-1-infected individuals, with the objective to reverse residual T-cell dysfunction.

METHODS

Twelve HIV-1(+) patients on suppressive cART with baseline CD4 T-cell counts >400 cells/mm(3) blood were randomised into one of three groups: (1) vaccine, IL-2, GM-CSF and rhGH (n=3); (2) vaccine alone (n=4); or (3) IL-2, GM-CSF and rhGH (n=5). Samples were collected at weeks 0, 1, 2, 4, 6, 8, 12, 16, 24 and 48. Interferon (IFN)-γ, IL-2, IL-4 and perforin ELISpot assays performed at each time point quantified functional responses to Gag p17/p24, Nef, Rev, and Tat peptides; and detailed T-cell immunophenotyping was undertaken by flow cytometry. Proviral DNA was also measured.

RESULTS

Median baseline CD4 T-cell count was 757 cells/mm(3) (interquartile range [IQR] 567-886 cells/mm(3)), median age 48 years (IQR 42-51 years), and plasma HIV-1-RNA <50 copies/ml for all subjects. Patients who received vaccine plus IL-2, GM-CSF and rhGH (group 1) showed the most marked changes. Assessing mean changes from baseline to week 48 revealed significantly elevated numbers of CD4 T cells (p=0.0083) and improved CD4/CD8 T-cell ratios (p=0.0033). This was accompanied by a significant reduction in expression of CD38 on CD4 T cells (p=0.0194), significantly increased IFN-γ and IL-2 production in response to Gag (p=0.0122) and elevated IFN-γ production in response to Tat (p=0.041) at week 48 compared to baseline. Subjects in all treatment groups showed significantly reduced PD-1 expression at week 48 compared to baseline, with some reductions in proviral DNA.

CONCLUSIONS

Multifarious immunotherapeutic approaches in the context of fully suppressive cART further reduce immune activation, and improve both CD4 T-lymphocyte counts and HIV-1-specific T-cell responses (NCT01130376).

Doctor-patient concordance during HIV treatment switching decision-making

OBJECTIVES

The aim of the study was to explore levels of doctor-patient concordance during the making of decisions regarding HIV treatment switching and stopping in relation to patient health-related outcomes.

METHODS

Adult patients attending five HIV clinics in the United Kingdom were requested to complete the study questionnaire, which included a Concordance Scale, and measures of symptoms [Memorial Symptom Assessment Short Form (MSAS) index], quality of life (EuroQol), satisfaction, adherence and sexual risk behaviour. Clinical health measures (HIV viral load and CD4 cell count) were also obtained. A total of 779 patients completed the questionnaire, giving a response rate of 86%; of these 779 patients, 430 had switched or stopped their HIV treatment and were thus eligible for inclusion. Of these patients, 217 (50.5%) fully completed the Concordance Scale.

RESULTS

Concordance levels were high (88% scored between 30 and 40 on the scale; score range 10-40). Higher concordance was related to several patient outcomes, including: better quality of life (P=0.003), less severe and burdensome symptom experience (lower MSAS-physical score, P=0.001; lower MSAS-psychological score, P=0.008; lower MSAS-global distress index score, P=0.011; fewer symptoms reported, P=0.007), higher CD4 cell count (at baseline, P=0.019, and 6-12 months later, P=0.043) and greater adherence (P=0.029).

CONCLUSIONS

High levels of doctor-patient concordance in HIV treatment decision-making are associated with greater adherence and better physical and psychological functioning. More research is needed to establish a causal relationship between concordance and these outcomes.

Unstructured treatment interruption of antiretroviral therapy in clinical practice: a systematic review

OBJECTIVE

To characterize the frequency, reasons, risk factors, and consequences of unstructured anti-retroviral treatment interruptions.

METHOD

Systematic review.

RESULTS

Seventy studies were included. The median proportion of patients interrupting treatment was 23% for a median duration of 150 days. The most frequently reported reasons for interruptions were drug toxicity, adverse events, and side-effects; studies from developing countries additionally cited treatment costs and pharmacy stock-outs as concerns. Younger age and injecting drug use was a frequently reported risk factor. Other risk factors included CD4 count, socioeconomic variables, and pharmacy stock outs. Treatment interruptions increased the risk of death, opportunistic infections, virologic failure, resistance development, and poor immunological recovery. Proposed interventions to minimize interruptions included counseling, mental health services, services for women, men, and ethnic minorities. One intervention study found that the use of short message service reminders decrease the prevalence of treatment interruption from 19% to 10%. Finally, several studies from Africa stressed the importance of reliable and free access to medication.

CONCLUSION

Treatment interruptions are common and contribute to worsening patient outcomes. HIV/AIDS programmes should consider assessing their causes and frequency as part of routine monitoring. Future research should focus on evaluating interventions to address the most frequently reported reasons for interruptions.

T-cell dysfunction in HIV-1 infection: targeting the inhibitors

Since AIDS emerged almost three decades ago, there have been considerable advances in the field of antiretroviral chemotherapy for those chronically infected with HIV-1. However, this therapy is noncurative and as our understanding of HIV-1 immunopathogenesis increases, it is becoming apparent that further therapeutic interventions are required to reverse the devastating effects of HIV-1 infection worldwide. While viral clearance remains the principle goal of HIV-1 treatment, this article describes immunotherapeutic options that target the immunological effects of the virus, to reduce its presence in the body and counteract viral-induced T-cell dysfunction and inhibition. Such approaches may augment existing antiretroviral therapy to overturn virus-induced T-cell anergy in the infected host, improving levels of immune control that reduce viremia and decrease the rate of transmission.

Virological rebound and its consequences during treatment interruption

PURPOSE OF REVIEW

This paper provides an overview of the current knowledge on virological rebound during treatment interruption and its consequences in patients with chronic HIV-1 infection.

RECENT FINDINGS

After interruption of antiretroviral therapy, plasma viremia inevitably returns to individual pretherapy set point levels in almost all patients with chronic HIV infection. This virological rebound leads to a state of massive immune activation and consequently an increased turnover of CD4+ and CD8+ T cells resulting in a biphasic decay of T-helper cell numbers. Rebound has been shown to be associated with an increased risk of clinical events by some (albeit not all) randomized trials published during the last few months. Secondary consequences of immunologic deterioration include worsening of comorbidity (e.g. hepatitis and renal impairment) and an increased risk of cardiovascular disease as well as an elevated HIV transmission risk during treatment interruption. The individual course after treatment interruption cannot be predicted by any of the known surrogate markers.

SUMMARY

Treatment interruptions cannot be recommended in HIV-infected patients outside clinical trials, especially when profound immune deficiency is found to be preexisting.

Full-length characterization of A1/D intersubtype recombinant genomes from a therapy-induced HIV type 1 controller during acute infection and his noncontrolling partner

To increase the understanding of mechanisms of HIV control we have genetically and immunologically characterized a full-length HIV-1 isolated from an acute infection in a rare case of undetectable viremia. The subject, a 43-year-old Danish white male (DK1), was diagnosed with acute HIV-1 infection after 1 year in Uganda. Following transient antiretroviral therapy DK1 maintained undetectable viral load for more than 10 years. His Ugandan wife (UG1) developed high viral load. HIV-1 sequences from both individuals were compared by bootscanning for recombination break points. Diversity plots and phylogenic trees were constructed and diversity and evolutionary distances were calculated. Intracellular IFN-gamma in CD8(+)CD3(+) T-lymphocyte reactions was investigated by intracellular flow cytometry (IC-FACS). Virus isolates from both patients were A1D intersubtype recombinants showing 98% sequence homology in shared regions. Four of seven crossover points were identical; however, the env gene from UG1 was subtype D, but A1 in DK1. Both viruses encoded proteins of the expected length and replicated equally well in vitro. DK1 and UG1 shared the HLA-A02 tissue type. HLA-A02-restricted CD8(+) T cell IFN-gamma IC-FACS response in DK1 was detected against only one (Pol(476)) of 23 conserved epitopes. Neutralizing antibodies were induced only to the homologous isolate. These results indicate an A1D intersubtype recombination or transmission of a minor variant. Transient early antiretroviral therapy may have induced full HIV-1 control in this individual mediated by a narrow specific cytotoxic T lymphocyte and neutralizing antibody response and/or other factors yet to be characterized.

Combined use of cytokines, hormones and therapeutic vaccines during effective antiretroviral therapy

Immune-based therapies using vaccines, cytokines and hormones are being considered in the context of effective antiretroviral therapy to induce immunologically defined long-term nonprogressor status in chronically infected HIV-1 patients. Such immunotherapy must allow induction or regeneration of anti-HIV-1 immune responses with the potential to control viremia, activate and eradicate viral reservoirs, and alleviate the immunosuppression caused by HIV-1, eventually possibly reaching the status of a virologically defined ‘elite controller’ with an absence of detectable viremia and no progression to disease over a long period of time. This article summarizes pilot studies utilizing therapeutic vaccines, cytokines and/or hormones in treated HIV-1 infection, and focuses on novel agents and immunotherapeutic options that may have the potential to augment or replace existing antiretroviral therapy with the aim of inducing nonprogressor status in the infected host.

Three-Year Immune Reconstitution in PI-Sparing and PI-Containing Antiretroviral Regimens in Advanced HIV-1 Disease

Background

The long-term immunological benefit of protease inhibitor (PI)-sparing antiretroviral therapy (ART) using non-nucleoside reverse transcriptase inhibitors (NNRTIs) remains poorly investigated.

Methods

A total of 120 ART-naive, HIV-1-infected participants were included in the immunology substudy of INITIO, an international randomized trial comparing two NRTIs (didanosine + stavudine) combined with either: one NNRTI (efavirenz; EFV), one non-boosted PI (nelfinavir; NFV), or one NNRTI + one PI (EFV/NFV). CD4+ T-cell counts, HIV-1 plasma RNA load (VL), T-cell pheno-type, T-cell proliferation and IFN-γ production against opportunistic/recall and HIV-1 antigens/peptides were compared at baseline and at week (W) 96 and W156.

Results

Participants (37 EFV, 44 NFV, 39 EFV/NFV) had similar baseline VL; median CD4+ T-cell counts/mm3 were: 144 (64–303) EFV, 212 (42–313) NFV and 257 (86–331) EFV/NFV. At W156, the proportion of patients with VL ≤50 copies/ml was not different between the arms ( P=0.3). From baseline to W156 there was a significant increase in CD4+ T-cell counts ( P<0.001) and in naive CD4+ T cells ( P<0.001), with no difference between arms and percentages of total and activated CD8+ T cells decreased significantly ( P<0.001) in all arms. The decrease in activated memory CD4+T-cells was significantly greater in the EFV arm at W96 ( P=0.03) and W156 ( P=0.01), but did not persist after adjusting for baseline CD4+ T-cell counts. During follow-up, responses to opportunistic pathogens increased in all patients while specific T-cell responses to HIV-1-p24 and gp160 recombinant proteins or to Gag and Nef peptides were not restored.

Conclusion

Regimens using/sparing PIs provide similar levels of long-term immune reconstitution even in patients with low CD4+ T-cell counts.