Plasma nevirapine concentrations predict virological and adherence failure in Kenyan HIV-1 infected patients with extensive antiretroviral treatment exposure

Nevirapine plasma concentration is associated with virologic failure and the emergence of drug-resistant mutations among HIV patients in Kenya: A cross sectional study

This study aimed to determine the association between the plasma concentration of nevirapine (NVP) and clinical outcomes. In this cross-sectional study, sociodemographic and clinical data were collected from 233 HIV patients receiving NVP-based first-line antiretroviral therapy (ART) regimens in Nairobi, Kenya. The mean age was 41.2 (SD ± 11.9) years. Fifty-four (23.2%) patients had virological failure (>1000 copies/mL), whereas 23 (9.9%) were infected with drug-resistant HIV strains. Eleven patients had nucleoside reverse transcriptase inhibitor resistance mutations, including M184V and T215Y, whereas 22 had non-nucleoside reverse transcriptase inhibitor resistance mutations, including G190A, K103N, V106A, Y181C, A98G, and Y188L. The median NVP plasma concentration was 6180 ng/mL (IQR 4444-8843 ng/mL), with 38 (16.3%) patients having suboptimal NVP plasma levels of <3400 ng/mL. The majority 23 of the 38 (60.5%) patients with NVP Cmin < 3400 ng/mL were significantly infected with drug-resistant HIV virus (P = .001). In the multivariate analysis, the time taken to arrive at the ART clinic (β -11.1, 95% CI -21.2 to -1.1; P = .031), higher HIV viral load (β -2008, 95% CI -3370.7 to -645.3; P = .004), and the presence of HIV drug resistance mutation (β 3559, 95% CI 2580.8-4537.2; P = .0001) were associated with NVP plasma concentration. A significant proportion of patients receiving the NVP-based regimen had supra- and sub-therapeutic plasma concentrations. Higher HIV viral load and the presence of HIV drug-resistant mutations are important factors associated with NVP plasma concentrations.

A mAb for the detection of the antiretroviral drug emtricitabine

Antibody-based testing for emtricitabine (FTC), a critical component of pre-exposure prophylaxis and antiretroviral therapy, would provide low-cost detection for clinical monitoring to improve adherence. We developed a mAb (5D2) to FTC and demonstrated its high specificity and physiologically relevant linear range of detection in a competitive enzyme immunoassay. Thus, this mAb is a key reagent that will enable simple and low-cost lateral flow assays and enzyme immunoassays for adherence monitoring.

Measuring patient engagement with HIV care in sub-Saharan Africa: a scoping study

INTRODUCTION

Engagement with HIV care is a multi-dimensional, dynamic process, critical to maintaining successful treatment outcomes. However, measures of engagement are not standardized nor comprehensive. This undermines our understanding of the scope of challenges with engagement and whether interventions have an impact, complicating patient and programme-level decision-making. This study identified and characterized measures of engagement to support more consistent and comprehensive evaluation.

METHODS

We conducted a scoping study to systematically categorize measures the health system could use to evaluate engagement with HIV care for those on antiretroviral treatment. Key terms were used to search literature databases (Embase, PsychINFO, Ovid Global-Health, PubMed, Scopus, CINAHL, Cochrane and the World Health Organization Index Medicus), Google Scholar and stakeholder-identified manuscripts, ultimately including English evidence published from sub-Saharan Africa from 2014 to 2021. Measures were extracted, organized, then reviewed with key stakeholders.

RESULTS AND DISCUSSION

We screened 14,885 titles/abstracts, included 118 full-texts and identified 110 measures of engagement, categorized into three engagement dimensions ("retention," "adherence" and "active self-management"), a combination category ("multi-dimensional engagement") and "treatment outcomes" category (e.g. viral load as an end-result reflecting that engagement occurred). Retention reflected status in care, continuity of attendance and visit timing. Adherence was assessed by a variety of measures categorized into primary (prescription not filled) and secondary measures (medication not taken as directed). Active self-management reflected involvement in care and self-management. Three overarching use cases were identified: research to make recommendations, routine monitoring for quality improvement and strategic decision-making and assessment of individual patients.

CONCLUSIONS

Heterogeneity in conceptualizing engagement with HIV care is reflected by the broad range of measures identified and the lack of consensus on "gold-standard" indicators. This review organized metrics into five categories based on the dimensions of engagement; further work could identify a standardized, minimum set of measures useful for comprehensive evaluation of engagement for different use cases. In the interim, measurement of engagement could be advanced through the assessment of multiple categories for a more thorough evaluation, conducting sensitivity analyses with commonly used measures for more comparable outputs and using longitudinal measures to evaluate engagement patterns. This could improve research, programme evaluation and nuanced assessment of individual patient engagement in HIV care.

Measuring patient engagement with HIV care in sub-Saharan Africa: a scoping study

INTRODUCTION

Engagement with HIV care is a multi-dimensional, dynamic process, critical to maintaining successful treatment outcomes. However, measures of engagement are not standardized nor comprehensive. This undermines our understanding of the scope of challenges with engagement and whether interventions have an impact, complicating patient and programme-level decision-making. This study identified and characterized measures of engagement to support more consistent and comprehensive evaluation.

METHODS

We conducted a scoping study to systematically categorize measures the health system could use to evaluate engagement with HIV care for those on antiretroviral treatment. Key terms were used to search literature databases (Embase, PsychINFO, Ovid Global-Health, PubMed, Scopus, CINAHL, Cochrane and the World Health Organization Index Medicus), Google Scholar and stakeholder-identified manuscripts, ultimately including English evidence published from sub-Saharan Africa from 2014 to 2021. Measures were extracted, organized, then reviewed with key stakeholders.

RESULTS AND DISCUSSION

We screened 14,885 titles/abstracts, included 118 full-texts and identified 110 measures of engagement, categorized into three engagement dimensions ("retention," "adherence" and "active self-management"), a combination category ("multi-dimensional engagement") and "treatment outcomes" category (e.g. viral load as an end-result reflecting that engagement occurred). Retention reflected status in care, continuity of attendance and visit timing. Adherence was assessed by a variety of measures categorized into primary (prescription not filled) and secondary measures (medication not taken as directed). Active self-management reflected involvement in care and self-management. Three overarching use cases were identified: research to make recommendations, routine monitoring for quality improvement and strategic decision-making and assessment of individual patients.

CONCLUSIONS

Heterogeneity in conceptualizing engagement with HIV care is reflected by the broad range of measures identified and the lack of consensus on "gold-standard" indicators. This review organized metrics into five categories based on the dimensions of engagement; further work could identify a standardized, minimum set of measures useful for comprehensive evaluation of engagement for different use cases. In the interim, measurement of engagement could be advanced through the assessment of multiple categories for a more thorough evaluation, conducting sensitivity analyses with commonly used measures for more comparable outputs and using longitudinal measures to evaluate engagement patterns. This could improve research, programme evaluation and nuanced assessment of individual patient engagement in HIV care.

Permeation Challenges of Drugs for Treatment of Neurological Tuberculosis and HIV and the Application of Magneto-Electric Nanoparticle Drug Delivery Systems

The anatomical structure of the brain at the blood-brain barrier (BBB) creates a limitation for the movement of drugs into the central nervous system (CNS). Drug delivery facilitated by magneto-electric nanoparticles (MENs) is a relatively new non-invasive approach for the delivery of drugs into the CNS. These nanoparticles (NPs) can create localized transient changes in the permeability of the cells of the BBB by inducing electroporation. MENs can be applied to deliver antiretrovirals and antibiotics towards the treatment of human immunodeficiency virus (HIV) and tuberculosis (TB) infections in the CNS. This review focuses on the drug permeation challenges and reviews the application of MENs for drug delivery for these diseases. We conclude that MENs are promising systems for effective CNS drug delivery and treatment for these diseases, however, further pre-clinical and clinical studies are required to achieve translation of this approach to the clinic.

Nevirapine and tuberculosis predict first-line treatment failure in HIV patients in Indonesia: Case-control study

Introduction

Indonesia antiretroviral therapy guideline suggests the use of Non-Nucleoside Reverse Transcriptase Inhibitor (NNRTI)-based regiments as first line of HIV treatment and Protease Inhibitor to replace NNRTI when treatment failure occurred. This case-control study was aimed to study factors predicting first-line ART treatment failure among HIV positive patients aged >15 years, non-pregnant, and registered in our institution, Indonesia.

Methods

Diagnosis of HIV treatment failure was made according to the standard WHO criteria. Demographic and outcome variables were recorded. The association between variables were analyzed by Chi-square test with odds ratios (OR) and 95% confidence intervals (95% CI), followed by multivariate analysis using logistic regression test.

Results

Twenty-six index cases and 26 age- and sex-matched control cases were included in the study with a mean age of 32.27 ± 8.7 years and 32.88 ± 8.15 years, respectively. Median time for switching to second-line (Lopinavir/ritonavir, LPV/r) was 46.32 ± 30.21 months. Patients presented with tuberculosis and treated by nevirapine as the first-line treatment were 26.6-folds (95% CI: 2.41-293.81, p = 0.007) and 6.7-folds (95% CI: 1.56-28.45, p = 0.011) higher risk for treatment failure, respectively.

Conclusions

The presence of tuberculosis and the use of nevirapine in first-line treatment were strong predictors for first-line ARV treatment failure, suggesting for closer clinical monitoring for patients with those conditions. A further and larger prospective cohort study is needed to confirm the findings in this study.

Adherence to antiretroviral therapy among HIV infected pregnant women in public health sectors: a pilot of Chilenje level one Hospital Lusaka, Zambia

Introduction

regular use of Antiretroviral Therapy (ART) in pregnancy and breastfeeding reduces the odds of Mother-to-Child HIV Transmission (MTCT). However, adherence to ART is critical for MTCT to be successful. The present study investigated factors that influence adherence to ART among HIV infected pregnant women in Zambia.

Methods

a cross-sectional study design was conducted involving 71 HIV infected pregnant women who were advised to join the Prevention of Mother-to-Child HIV Transmission (PMTCT) program during their routine Antenatal clinic (ANC) visit and were on ART for more than six months. We used the Medication Possession Ratio (MPR) to quantify adherence levels. We used logistic regression to establish factors that influence adherence to ART.

Results

a total of 71 HIV infected pregnant women with a median age of 27years (IQR, 25-30) were enrolled in the study. There was evidence of a difference in adherence levels between pregnant women above 30 years and ones between 15 years and 30 years (P<0.001). Median adherence levels in this group were found to be at 96%(IQR 89-97). The main predictor of adherence in this population was marital status (being on separation) and age. The women who were on separation were 0.14 times less likely to adhere to option B+ compared to married women.

Conclusion

adherence to option B+ among pregnant women is low. Adherence was significantly influenced by marital status (being on separation) and age. Efforts to improve adherence should be directed towards women on separation and young adults (< 30 years of age).

Development and validation of the first point-of-care assay to objectively monitor adherence to HIV treatment and prevention in real-time in routine settings

OBJECTIVE

HIV prevention and treatment studies demonstrate that pharmacologic adherence metrics are more accurate than self-report. Currently available metrics use liquid-chromatography/tandem-mass-spectrometry (LC-MS/MS), which is expensive and laboratory-based. We developed a specific and sensitive antibody against tenofovir, the backbone of treatment and prevention, but conversion to a lateral flow assay (LFA) - analogous to a urine pregnancy test - is required for point-of-care testing. We describe the development of the first LFA to measure antiretroviral adherence in real-time.

METHODS

Previous work in a directly observed therapy study of providing tenofovir disoproxil fumarate (TDF) to HIV-noninfected volunteers at various simulated adherence patterns defined the appropriate cut-off for the LFA (1500 ng tenofovir/ml urine). We developed the LFA using a sample pad for urine; a conjugate pad coated with TFV-specific antibodies conjugated to colloidal gold nanoparticles; a nitrocellulose membrane striped with tenofovir-antigen (test line) and a control line; with an absorbent pad to draw urine across the reaction membrane.

RESULTS

We tested 300 urine samples collected from the directly observed therapy study by this LFA and the gold-standard method of LC-MS/MS. The LFA demonstrated 97% specificity (95% CI 93-99%) and 99% sensitivity (94-100%) compared with LC-MS/MS. The LFA accurately classified 98% of patients who took a dose within 24 h as adherent.

CONCLUSION

We describe the development and validation of the first point-of-care assay to measure short-term adherence to HIV prevention and treatment in routine settings. The assay is low-cost, easy-to-perform and measures the breakdown product (tenofovir) of both TDF and tenofovir alafenamide (TAF). This assay has the potential to improve HIV and PrEP outcomes worldwide by triggering differentiated service delivery with further study merited.

Antiretroviral concentration measurements as an additional tool to manage virologic failure in resource limited settings: a case control study

Background

Several studies demonstrate a correlation between sub-therapeutic concentrations of antiretroviral drugs and virologic failure. We examined the sensitivity, specificity and predictive values of sub-therapeutic drug levels in predicting viralogic failure.

Methods

This was a case control study with cases being samples of participants with virologic failure, and controls samples of participants with virologic suppression. We analyzed samples obtained from participants that had been on antiretroviral treatment (ART) for at least 6 months. Virologic failure was defined as HIV-RNA viral load ≥ 1000 copies/ml. Sub-therapeutic drug levels were defined according to published reference cutoffs. The diagnostic validity of drug levels for virologic failure was assessed using plasma viral loads as a gold standard.

Results

Sub-therapeutic ART concentrations explained only 38.2% of virologic failure with a probability of experiencing virologic failure of 0.66 in a patient with low drug levels versus 0.25 for participants with measurements within or above the normal range. Approximately 90% of participants with ART concentrations above the lower clinical cut off did not have virologic failure.

Conclusions

These results support prior indication for therapeutic drug monitoring in cases of suspected virologic failure.

Measuring Adherence to Antiretroviral Therapy via Hair Concentrations in India

BACKGROUND

Objective adherence measures are of increasing interest in antiretroviral treatment (ART) monitoring. Hair ART levels predict virologic suppression, and hair is easy to collect and store. No previous study has examined hair levels in an India-based cohort or laboratory.

METHODS

Small hair samples were collected from HIV-positive participants on either efavirenz (EFV)-based or nevirapine (NVP)-based ART in a South India-based study. Hair samples were split and analyzed for EFV or NVP in the University of California, San Francisco -based Hair Analytical Laboratory and the analytic laboratory of the Division of Nutrition at St. John's Research Institute, Bangalore, India, using liquid chromatography/tandem mass spectrometry. Agreement (using Bland-Altman methods) and rank correlation between the 2 laboratories' hair levels were calculated. Rank correlation between self-reported adherence (SRA) over the previous month using a visual analog scale and hair ART levels was calculated.

RESULTS

Among 75 participants (38 on NVP; 37 on EFV), the correlation between NVP levels generated by the 2 laboratories was 0.66 (P < 0.0001) and between EFV levels was 0.87 (P < 0.0001). Measurements from St. John's Research Institute were usually within 20% of those from the University of California, San Francisco Hair Analytical Laboratory. SRA was essentially uncorrelated with hair antiretroviral levels for either drug (all correlations < 0.04). Hair levels showed variability in adherence although SRA was >85% in all participants.

CONCLUSIONS

Hair ART levels measured by both an India-based laboratory and the standard U.S.-based laboratory showed generally high agreement and correlation, demonstrating local capacity. As in many other cohorts, hair ART levels and SRA were not well-correlated, likely indicating limitations in self-report and the need for objective adherence monitoring in resource-limited settings.

Brief Report: Validation of a Urine Tenofovir Immunoassay for Adherence Monitoring to PrEP and ART and Establishing the Cutoff for a Point-of-Care Test

BACKGROUND

Current pharmacologic adherence monitoring for antiretrovirals involves expensive, labor-intensive liquid chromatography/tandem mass spectrometry (LC-MS/MS)-based methods. Antibody-based assays can monitor and support adherence in real time. We developed a tenofovir (TFV)-based immunoassay and further validated it in a directly observed therapy (DOT) study.

DESIGN

Pharmacologic DOT study of TFV disoproxil fumarate (TDF)/emtricitabine (FTC) administered to HIV-noninfected volunteers.

METHODS

The TARGET study provided directly observed TDF 300 mg/FTC 200 mg 7 (high adherence), 4 (moderate), and 2 doses/week (low) to 30 volunteers (10/group) in Thailand, collecting a total of 637 urine samples over 6 weeks of administration and during washout. ELISA measured urine TFV levels by the immunoassay and LC-MS/MS-based concentrations served as the gold standard. A mixed-effects regression model evaluated cutoffs for a point-of-care assay. Performance characteristics of the immunoassay were compared with LC-MS/MS at a chosen cutoff.

RESULTS

Median TFV levels were 12,000 ng/mL by the immunoassay 1 day after dosing; 5000 ng/mL 2 days after dosing; 1500 ng/mL 3 days after dosing; and below the lower limit of quantification thereafter (≥4 days). An immunoassay cutoff of 1500 ng/mL accurately classified 98% of patients who took a dose 24 hours ago as adherent. The specificity and sensitivity of the immunoassay compared with LC-MS/MS at the 1500 ng/mL cutoff were 99% and 94%; the correlation between TFV levels by the 2 assays was high (0.92, P < 0.00001).

CONCLUSIONS

We have developed a novel TFV immunoassay that is highly specific, sensitive, and correlates strongly with LC-MS/MS measurements in a large DOT study. Adherence benchmarks from this DOT study will guide the development of a low-cost rapid point-of-care test for pre-exposure prophylaxis and antiretroviral treatment adherence monitoring and interventions.

Alcohol-related intentional nonadherence to antiretroviral therapy among people living with HIV, Cape Town, South Africa

Alcohol use may have significant negative impacts on individuals' ability to remain adherent to antiretroviral therapy (ART), and may also yield other negative psychosocial, health-related, and behavioral outcomes. In addition, false beliefs about the consequences of mixing alcohol with ART use may cause individuals to avoid taking ART when drinking (alcohol-related ART avoidance). Although research conducted in the U.S. and Europe has reported on alcohol-ART avoidance, the current study presents among the first quantitative evidence of alcohol-related intentional ART nonadherence in South Africa. Patients receiving ART from a community clinic in Cape Town (N = 441) completed anonymous surveys of alcohol use, ART adherence, and alcohol-ART avoidance. Results showed that 292 (66%) participants reported current alcohol use; 25% who use alcohol believed that people who drink should stop taking ART when they are drinking and 24% stop their own ART when drinking. Alcohol-ART avoidance mediated the association between alcohol use and ART adherence. Results were robust when controlling for participant age, gender, current care status, and first- versus second-line ART. We found alcohol-ART avoidance may threaten successful ART in South Africa. Corrective messages that take a harm reduction approach to maximize ART adherence when drinking should be implemented in existing clinical services.

Monotypic low-level HIV viremias during antiretroviral therapy are associated with disproportionate production of X4 virions and systemic immune activation

OBJECTIVE

During effective antiretroviral therapy (ART), low-level plasma viremias (LLV) (HIV RNA >30-1000 copies/ml) can be detected intermittently. We hypothesized that systemic inflammation is associated with LLV either as the cause or result of the production of virions from clonally expanded cells.

METHODS

Prospective cohort study of HIV-infected ART-naive Peruvians enrolled prior to ART and followed for 2 years. Plasma HIV RNA and peripheral blood mononuclear cell (PBMC) HIV DNA concentrations were quantified pre-ART from individuals whose plasma HIV RNA was ART-suppressed. Inflammatory biomarker concentrations were measured pre and during ART. Single-genome amplification (SGA) derived HIV env and pol genotypes from pre-ART and LLV specimens. Antiretroviral levels during ART assessed adherence. Statistical associations and phylogenetic relationships were examined.

RESULTS

Among 82 participants with median plasma HIV RNA less than 30 copies/ml, LLV were detected in 33 of 82 (40%), with a LLV median HIV RNA of 73 copies/ml. Participants with vs. without LLV had significantly higher pre-ART plasma HIV RNA (P < 0.001) and PBMC HIV DNA (P < 0.007); but, during ART, their antiretroviral drug levels were similar. LLV env sequences were monotypic in 17 of 28 (61%) and diverse in 11 of 28 (39%) participants. Those with the monotypic vs. diverse LLV pattern had elevated hsCRP and sCD163 (P = 0.004) and LLV with more X4 variants (P = 0.02).

CONCLUSION

In individuals with monotypic LLV sequences, higher levels of pre-ART HIV DNA and RNA, systemic inflammation and X4 viruses suggest an interaction between inflammation and the production of virions from proliferating infected cells, and that naïve T cells may be a source of LLV.

Technological methods to measure adherence to antiretroviral therapy and preexposure prophylaxis

PURPOSE OF REVIEW

The WHO's Consolidated Guidelines (2016) call for research on improved methods to proactively monitor adherence and identify those individuals who have the greatest needs for adherence support. This review aims to elucidate the latest technologies available to measure adherence to HIV antiretroviral therapy and preexposure prophylaxis against HIV infection and present their utility in various settings and populations.

RECENT FINDINGS

Within the last few years, advances have been made in the features of existing technology to measure adherence (real-time electronic adherence measurements), additional approaches have been developed (digital medicine systems) and improved (short message service surveys), and point of care testing for pharmacokinetic measures are under development.

SUMMARY

Technology advances in adherence measurement are promising for improved accuracy and, in some cases, the ability to intervene with adherence challenges in real time. This progress will greatly further our understanding of adherence behavior, as well as the ability to effectively link interventions with individuals who need them, thus maximizing the clinical and public health benefits of both antiretroviral therapy and preexposure prophylaxis.

K. HK, Ramachandran G, Shet A. Sub-therapeutic nevirapine concentration during antiretroviral treatment initiation among children living with HIV: Implications for therapeutic drug monitoring

Nevirapine, a component of antiretroviral therapy (ART) in resource-limited settings, known for auto-induction of metabolism, is initiated at half therapeutic dose until day 14 (‘lead-in period’), and subsequently escalated to full dose. However, studies have shown that this dosing strategy based on adult studies may not be appropriate in children, given that younger children have higher drug clearance rates. In this prospective cohort study, we studied trough plasma nevirapine levels by high performance liquid chromatography (HPLC) at days 7, 14 (lead-in period) and 28 (full dose period) after ART initiation amongst HIV-1 infected children initiating nevirapine-based ART in southern India. Among the 20 children (50% male, median age 9 years) included in the study, sub-therapeutic trough plasma nevirapine concentration (<4μg/ml) was seen in 65% (13/20) of children during the lead-in period within two weeks of ART initiation and among 10% of children at 4 weeks during full-dose nevirapine. Adherence was documented as ≥95% in all children by both caregiver self-report and pill count. Median nevirapine concentrations achieved at week 1 was 4.8 μg/ml, significantly lower than 8 μg/ml, the concentration achieved at week 4 (p = 0.034). Virological failure at one year of ART was observed in six children, and was not associated with median nevirapine concentration achieved during week 1, 2 or 4. We conclude that the dose escalation strategy currently practiced among young children living with HIV-1 resulted in significant subtherapeutic nevirapine concentration (≤4μg/ml) during the lead-in period. We call for a closer look at pediatric-focused dosing strategies for nevirapine initiation in young children. Further studies to establish age-appropriate threshold nevirapine concentration are warranted in young children to corroborate the role of therapeutic drug monitoring in predicting virological outcome.