Preferred antiretroviral drugs for the next decade of scale up

A conceptualisation of scale-up and sustainability of social innovations in global health: a narrative review and integrative framework for action

BACKGROUND

The scale-up and sustainability of social innovations for health have received increased interest in global health research in recent years; however, these ambiguous concepts are poorly defined and insufficiently theorised and studied. Researchers, policymakers, and practitioners lack conceptual clarity and integrated frameworks for the scale-up and sustainability of global health innovations. Often, the frameworks developed are conceived in a linear and deterministic or consequentialist vision of the diffusion of innovations. This approach limits the consideration of complexity in scaling up and sustaining innovations.

OBJECTIVE

By using a systems theory lens and conducting a narrative review, this manuscript aims to produce an evidence-based integrative conceptual framework for the scale-up and sustainability of global health innovations.

METHOD

We conducted a hermeneutic narrative review to synthetise different definitions of scale-up and sustainability to model an integrative definition of these concepts for global health. We have summarised the literature on the determinants that influence the conditions for innovation success or failure while noting the interconnections between internal and external innovation environments.

RESULTS

The internal innovation environment includes innovation characteristics (effectiveness and testability, monitoring and evaluation systems, simplification processes, resource requirements) and organisational characteristics (leadership and governance, organisational change, and organisational viability). The external innovation environment refers to receptive and transformative environments; the values, cultures, norms, and practices of individuals, communities, organisations, and systems; and other contextual characteristics relevant to innovation development.

CONCLUSION

From these syntheses, we proposed an interconnected framework for action to better guide innovation researchers, practitioners, and policymakers in incorporating complexity and systemic interactions between internal and external innovation environments in global health.

Antiretroviral therapy uptake and predictors of virological failure in patients with HIV receiving first-line and second-line regimens in Johannesburg, South Africa: a retrospective cohort data analysis

OBJECTIVE

This study described the demographics, treatment information and identified characteristics associated with virological failure and being lost to follow-up (LTFU) for patients with HIV on first-line and second-line antiretroviral therapy (ART) regimens in a large South African cohort.

DESIGN

A quantitative retrospective cohort study using secondary data analysis.

SETTING

Seven Johannesburg inner city facilities.

PARTICIPANTS

Unique records of 123 002 people with HIV receiving ART at any point in the period 1 April 2004 to 29 February 2020 were included.

MEASURES

Demographic characteristics, ART status, CD4 count information and retention status were collected and analysed as covariates of outcomes (viral load (VL) and LTFU).

RESULTS

Of the total study patients, 95% (n=1 17 260) were on a first-line regimen and 5% (n=5742) were on a second-line regimen. Almost two-thirds were female (64%, n=79 226). Most patients (60%, n=72 430) were initiated on an efavirenz-based, tenofovir disoproxil fumarate-based and emtricitabine-based regimen (fixed-dose combination). 91% (n=76 737) achieved viral suppression at least once since initiating on ART and 60% (n=57 981) remained in care as at the end of February 2020. Patients from the community health centre and primary healthcare clinics were not only more likely to be virally suppressed but also more likely to be LTFU. Patients on second-line regimens were less likely to reach viral suppression (adjusted OR (aOR)=0.26, CI=0.23 to 0.28) and more likely to be LTFU (aOR=1.21, CI=1.09 to 1.35). Being older (≥25 years) and having a recent CD4 cell count≥100 cells/µL were predictors of viral suppression and retention in patients on ART.

CONCLUSION

Patients on first-line regimens had higher VL suppression rates and were more likely to remain in care than those on a second-line regimen. Being younger and having low CD4 cell counts were associated with poor outcomes, suggesting priority groups for ART adherence support.

QT prolongation in HIV-positive patients: Review article

Introduction

Antiretrovirals have immensely increased the average life expectancy of HIV-positive patients. However, the incidence of QT interval prolongation and other arrhythmias has also increased.

Methods

Pubmed and Google Scholar were searched for relevant literature published between 1990 and 2019.

Results and discussion

HIV-positive patients with high viral load, low CD4 count, chronic inflammation, and autonomic neuropathy can develop QT interval prolongation. Another factor prolonging QT interval includes exposure to the HIV transactivator protein, which inhibits hERG K (+) channels controlling IKr K (+) currents in cardiomyocytes. Protease inhibitors inhibiting the CYP3A4 enzyme can also lead to QT interval prolongation. QT interval prolongation can potentially be exacerbated by opioids, antipsychotics, antibiotics, and antifungals, the adjunct medications often used in HIV-positive patients. Hepatic insufficiency in seropositive patients on antiretrovirals may also increase the risk of QT interval prolongation.

Conclusion

Baseline and follow-up EKG in the susceptible population is suggested.

Prevalence and predictors of long corrected QT interval in HIV-positive patients: a multicenter study

AIMS

HIV and highly active antiretroviral therapy (HAART) may affect cardiac conduction, and a higher incidence of sudden death has been recognized in HIV-positive patients. Nevertheless, predictors of prolonged corrected QT interval (cQT) have been poorly described. The aim of the study was to investigate the prevalence and predictors of long cQT in a cohort of HIV-positive patients.

METHODS

Consecutive HIV-positive patients followed in a primary prevention clinic at two Italian institutions were retrospectively enrolled. A 12-lead ECG was recorded in all patients; main clinical features were collected. Prevalence of long cQT (defined as cQT >470 ms in women and >450 ms in men) was the primary end-point. Secondary end-points were the identification of predictors of cQT prolongation, and the association between HAART and HIV-related features with long cQT.

RESULTS

Three hundred and fifty-one HIV-positive patients were included, 26 (7.4%) with long cQT. Mean age was higher among those with long cQT (51.6 vs. 57.6 years; P = 0.007). A higher prevalence of long cQT was reported for patients with a CD4+ cell count below 200 cells/μl at the moment of ECG (60 vs. 24.2%; P = 0.002) and with a nadir of CD4+ cell count below 200 cells/μl (91.3 vs. 58.6%; P = 0.001). At multivariate analysis, only the nadir of CD4+ cell count below 200 cells/μl consistently related to the presence of long cQT (odds ratio 5.8, 95% confidence interval 1.3-26.4).

CONCLUSION

A low CD4+ cell count is associated with long cQT independently from HAART in HIV-positive patients and may be useful to correctly stratify arrhythmic risk in these patients.

Heart failure in patients with human immunodeficiency virus: a review of the literature

Coronary artery disease represents the leading cause of death for HIV patients treated with highly active antiretroviral treatment. Besides this, an extensive amount of data related to the risk of overt heart failure and consequently of atrial fibrillation and sudden cardiac death (SCD) in this population has been reported. It seems that persistent deregulation of immunity in HIV-infected patients is a common pathway related to both of these adverse clinical outcomes. Despite the fact that atrial fibrillation and heart failure are relatively common in HIV, few data are reported about screening, diagnosis, and potential treatment of these conditions.

Whole-body immunoPET reveals active SIV dynamics in viremic and antiretroviral therapy-treated macaques

The detection of viral dynamics and localization in the context of controlled HIV infection remains a challenge and is limited to blood and biopsies. We developed a method to capture total-body simian immunodeficiency virus (SIV) replication using immunoPET (antibody-targeted positron emission tomography). The administration of a poly(ethylene glycol)-modified, (64)Cu-labeled SIV Gp120-specific antibody led to readily detectable signals in the gastrointestinal and respiratory tract, lymphoid tissues and reproductive organs of viremic monkeys. Viral signals were reduced in aviremic antiretroviral-treated monkeys but detectable in colon, select lymph nodes, small bowel, nasal turbinates, the genital tract and lung. In elite controllers, virus was detected primarily in foci in the small bowel, select lymphoid areas and the male reproductive tract, as confirmed by quantitative reverse-transcription PCR (qRT-PCR) and immunohistochemistry. This real-time, in vivo viral imaging method has broad applications to the study of immunodeficiency virus pathogenesis, drug and vaccine development, and the potential for clinical translation.

Simplification of antiretroviral therapy: a necessary step in the public health response to HIV/AIDS in resource-limited settings

The global scale-up of antiretroviral therapy (ART) over the past decade represents one of the great public health and human rights achievements of recent times. Moving from an individualized treatment approach to a simplified and standardized public health approach has been critical to ART scale-up, simplifying both prescribing practices and supply chain management. In terms of the latter, the risk of stock-outs can be reduced and simplified prescribing practices support task shifting of care to nursing and other non-physician clinicians; this strategy is critical to increase access to ART care in settings where physicians are limited in number. In order to support such simplification, successive World Health Organization guidelines for ART in resource-limited settings have aimed to reduce the number of recommended options for first-line ART in such settings. Future drug and regimen choices for resource-limited settings will likely be guided by the same principles that have led to the recommendation of a single preferred regimen and will favour drugs that have the following characteristics: minimal risk of failure, efficacy and tolerability, robustness and forgiveness, no overlapping resistance in treatment sequencing, convenience, affordability, and compatibility with anti-TB and anti-hepatitis treatments.

Blocking interaction of viral gp120 and CD4-expressing T cells by single-stranded DNA aptamers

To investigate the potential clinical application of aptamers to prevention of HIV infection, single-stranded DNA (ssDNA) aptamers specific for CD4 were developed using the systematic evolution of ligands by exponential enrichment approach and next generation sequencing. In contrast to RNA-based aptamers, the developed ssDNA aptamers were stable in human serum up to 12h. Cell binding assays revealed that the aptamers specifically targeted CD4-expressing cells with high binding affinity (Kd=1.59nM), a concentration within the range required for therapeutic application. Importantly, the aptamers selectively bound CD4 on human cells and disrupted the interaction of viral gp120 to CD4 receptors, which is a prerequisite step of HIV-1 infection. Functional studies showed that the aptamer polymers significantly blocked binding of viral gp120 to CD4-expressing cells by up to 70% inhibition. These findings provide a new approach to prevent HIV-1 transmission using oligonucleotide aptamers.