Scaling up antiretroviral therapy in resource-limited settings: adapting guidance to meet the challenges

How to properly define immunological nonresponse to antiretroviral therapy in people living with HIV? an integrative review

In recent decades, significant progress has been made in understanding the mechanisms underlying human immunodeficiency virus (HIV) infection and its treatment. Antiretroviral therapy (ART) has notable improved the life expectancy and quality of life for people living with HIV (PLHIV) by suppressing viral replication and promoting CD4+ T-cell recovery. However, despite its efficacy, approximately 10-40% of ART-treated PLHIV with virological suppression (<50 RNA copies/mL) do not achieve adequate immunological reconstitution. These PLHIV, classified as immunological non-responders (INR), experience higher morbidity and mortality rates compared to those with satisfactory immune reconstitution, known as immunological responders (IR). Various studies have explored the mechanisms contributing to immunological nonresponse, yet a major challenge remains: the lack of a standardized definition of immunological response and nonresponse across studies. Currently, definitions are inconsistent, limiting comparability between studies. This review proposes a clear and adequate classification for IR and INR PLHIV to support future advancements in understanding immunological recovery and improving the quality of life for ART-treated PLHIV.

Trough plasma nevirapine levels, immunologic and virologic responses in composite CYP2B6*6/*18 HIV-infected adult Nigerian patients

The influence of composite CYP2B6*6/*18 genotype on trough plasma nevirapine levels, HIV RNA levels (virologic response) and CD4+ T lymphocyte and absolute lymphocyte counts (immunologic response) of HIV-infected patients were evaluated. Patients with records of trough plasma nevirapine levels, CD4+ T lymphocyte, absolute lymphocyte and viral load counts at baseline and months 6 and 12 after initiation of nevirapine-based antiretroviral therapy combinations were retrospectively analysed. Participants were from a cohort of 150 patients previously genotyped and with measured plasma nevirapine levels. Relationship between genotype and nevirapine levels, absolute lymphocyte and CD4+ T lymphocyte counts and viral load were explored. Composite CYP2B6*6/*18 genotype was significantly associated with trough plasma nevirapine levels (geometric mean [standard deviation]: 4482 ng/ml [1349] of normal metabolizers vs. 4632 ng/ml [1793] of intermediate metabolizers vs. 6229 ng/ml [2549] of poor metabolizers; P < 0.001), but not the plasma HIV RNA levels, absolute lymphocyte and CD4+ T lymphocyte counts. Overall, immunologic response showed improvement with approximately 61.3% and 70.4% of patients with CD4+ T lymphocyte count >350 cells/mm³ at months 6 and 12 therapy duration respectively compared to 23.1% at baseline. Composite CYP2B6*6/*18 genotype correlated with plasma nevirapine levels but not immunologic and virologic responses.

Magnitude of optimal adherence and predictors for a low level of adherence among HIV/AIDS-infected adults in South Gondar zone, Northwest Ethiopia: a multifacility cross-sectional study

OBJECTIVES

This study aims to identify levels of adherence to antiretroviral therapy (ART) drugs and factors associated with them in Northwest Ethiopia. We hypothesise that in the era of COVID-19, there would be suboptimal adherence to ART drugs.

DESIGN

An observational cross-sectional study was conducted. Factors associated with the level of adherence were selected for multiple logistic regressions at a p value of less than 0.2 in the analysis. Statistically significant associated factors were identified at a p value less than 0.05 and adjusted OR with a 95% CI.

SETTING

The study was conducted in one specialised hospital and three district hospitals found in the South Gondar zone, Northwest Ethiopia.

PARTICIPANTS

About 432 people living with HIV/AIDS receiving highly active ART in South Gondar zone public hospitals and who have been on treatment for more than a 3-month period participated in the study.

PRIMARY AND SECONDARY OUTCOME MEASURES

Levels of adherence to ART drugs and their associated factors.

RESULTS

Among 432 study participants, 81.5% (95% CI: 78% to 85.2%) of participants were optimally adherent to ART drugs. Determinants of a low level of adherence: stigma or discrimination (OR=0.4, p=0.016), missed scheduled clinical visit (OR=0.45, p=0.034), being on tuberculosis treatment (OR=0.45, p=0.01), recent CD4 cell count less than 500 cells/mm³ (OR=0.3, p=0.023) and patients who had been on WHO clinical stage III at the time of ART initiation (OR=0.24, p=0.027) were factors significantly associated with adherence to ART drugs.

CONCLUSIONS

Level of adherence was relatively low compared with some local studies. The intervention targeted to reduce discrimination, counselling before initiation of treatment and awareness regarding compliance is advised to improve adherence to antiretroviral regimens.

Managing Advanced HIV Disease in a Public Health Approach

In 2017, the World Health Organization (WHO) published guidelines for the management of advanced human immunodeficiency virus (HIV) disease within a public health approach. Recent data suggest that more than a third of people starting antiretroviral therapy (ART) do so with advanced HIV disease, and an increasing number of patients re-present to care at an advanced stage of HIV disease following a period of disengagement from care. These guidelines recommend a standardized package of care for adults, adolescents, and children, based on the leading causes of morbidity and mortality: tuberculosis, severe bacterial infections, cryptococcal meningitis, toxoplasmosis, and Pneumocystis jirovecii pneumonia. A package of targeted interventions to reduce mortality and morbidity was recommended, based on results of 2 recent randomized trials that both showed a mortality reduction associated with delivery of a simplified intervention package. Taking these results and existing recommendations into consideration, WHO recommends that a package of care be offered to those presenting with advanced HIV disease; depending on age and CD4 cell count, the package may include opportunistic infection screening and prophylaxis, including fluconazole preemptive therapy for those who are cryptococcal antigen positive and without evidence of meningitis. Rapid ART initiation and intensified adherence interventions should also be proposed to everyone presenting with advanced HIV disease.

Assisted HIV partner notification services in resource-limited settings: experiences and achievements from Cameroon

INTRODUCTION

In 2007, the Cameroon Baptist Convention Health Services (CBCHS) initiated an assisted partner notification services (aPNS) public health programme to increase HIV case identification and reduce HIV incidence in the most affected regions of Cameroon. We describe large-scale implementation of aPNS and overall programmatic achievements in a resource-limited setting through 2015.

METHODS

CBCHS trained health advisors (HAs) from 16 CBCHS facilities and 22 non-CBCHS facilities to integrate aPNS into their existing jobs in five of the ten Cameroon regions. HAs recorded basic demographic, clinical and risk factor information from consenting index persons (IPs) and similar information about their sexual partners'/contact persons (CPs) on interview records and aPNS registers. These data were entered into an Epi-Info database. HAs provided pre-test counselling to CPs and offered them HIV testing in their home or other location. HAs educated IPs and CPs on HIV prevention and risk reduction, and referred IPs and HIV positive CPs to HIV care and treatment centres. Starting in 2014, HAs re-interviewed IPs 30 days after their initial aPNS interview to ascertain instances of social harms following partner notification. Continuous predictor and outcome variables were summarized using median and interquartile range, while categorical variables were summarized using percentages from 2007 to 2015.

RESULTS

A total of 18,730 IPs (71% women) received aPNS over nine years. IPs identified 21,057 CPs (67% men) (mean CP/IP 1.12), of whom 12,867 (61.1%) were notified of their exposure to HIV. A total of 9202 (71.5% of notified CPs) tested for HIV, 4764 (51.8%) of whom tested HIV positive (number of IPs needed to interview = 3.9); 3112 (65.3%) HIV-positive partners were referred to HIV care and treatment centres. Of the 976 IPs receiving aPNS in 2014 to 2015, for whom follow-up data were available, 11 (1.1%) reported physical intimate partner violence from CPs. Thus, 44.3% of 1224 CPs were notified through provider referral. Of the 784 CPs who tested for HIV, 157 were newly diagnosed and the overall HIV prevalence was 41.6% (326/784).

CONCLUSIONS

aPNS is feasible, can be brought to scale, yields a high level of case identification, and is infrequently associated with social harms and intimate partner violence.

Effect of cladribine tablets on lymphocyte reduction and repopulation dynamics in patients with relapsing multiple sclerosis

BACKGROUND

Immune reconstitution therapies (IRT) for patients with multiple sclerosis are used for short, intermittent treatment periods to induce immune resetting and allow subsequent treatment-free periods. Cladribine tablets are postulated to be an IRT that causes selective and transient reductions in CD19⁺ B cells and T cells, followed by reconstitution of adaptive immune function.

OBJECTIVE

To characterize long-term lymphocyte count changes in pooled data from the 2-year CLARITY and subsequent 2-year CLARITY Extension studies, and the PREMIERE registry (Long-term CLARITY cohort).

METHODS

Data from patients randomized to placebo (n = 435) or cladribine tablets 10 mg (MAVENCLAD^®; 3.5 mg/kg cumulative dose over 2 years, referred to as cladribine tablets 3.5 mg/kg; n = 685) in CLARITY or CLARITY Extension, including time spent in the PREMIERE registry were pooled to provide long-term follow-up data. The study investigated absolute lymphocyte counts (ALC) up to 312 weeks and B and T cell subsets up to 240 weeks after the first dose, in patients receiving placebo or cladribine tablets 3.5 mg/kg administered as two short (4 or 5 days) weekly treatments at the start of months 1 and 2 in each treatment year, followed by no further active treatment.

RESULTS

Treatment with cladribine tablets 3.5 mg/kg resulted in selective reductions in B and T lymphocytes. Lymphocyte recovery began soon after treatment in each of years 1 and 2. Median ALC recovered to the normal range and CD19⁺ B cells recovered to threshold values by week 84, approximately 30 weeks after the last dose of cladribine tablets in year 2. Median CD4⁺ T cell counts recovered to threshold values by week 96 (approximately 43 weeks after the last dose of cladribine tablets in year 2). Median CD8⁺ cell counts never dropped below the threshold value.

CONCLUSION

These results show the dynamics of lymphocyte count changes following treatment with cladribine tablets 3.5 mg/kg. The immune cell repopulation results provide further evidence that cladribine tablets may represent a form of IRT.

Predictors of non-adherence to antiretroviral therapy among HIV infected patients in northern Tanzania

BACKGROUND

Antiretroviral therapy (ART) has been shown to reduce HIV-related morbidity and mortality amongst those living with HIV and reduce transmission of the virus to those who are yet to be infected. However, these outcomes depend on maximum ART adherence, and HIV programs around the world make efforts to ensure optimal adherence. Predictors of ART non-adherence vary considerably across populations and settings with respect to demographic, psychological, behavioral and economic factors. The objective of this study is to investigate risk factors that predict non-adherence to antiretroviral treatment among HIV-infected individuals in northern Tanzania.

METHODS

At Kilimanjaro Christian Medical Centre (KCMC), a tertiary and referral hospital in northern Tanzania, we used an existing ART database to randomly select HIV-infected patients above 18 years of age who have been on triple ART for at least two years. We used interviewer administered structured questionnaires to cross-sectionally determine predictors of ART non-adherence. We determined non-adherence through retrospective review of pharmacy drug refill (PDR) records of the interviewed participants using a pharmacy database.

RESULTS

Non-adherence was defined as collecting less than 95% of expected monthly refills in the previous 2 years. Multivariable logistic regression model was used to determine the predictors of non-adherence. Of the 256 patients enrolled mean age was 44 years (SD ± 11) and median CD4 count was 499 cells per microliter (IQR 332-690). Median PDR adherence was 71% (IQR 58%-75%). Non-adherence was associated with younger age and unemployment.

CONCLUSION

In this setting, adherence strategies could be adapted to address issues facing young adults, and those with household challenges such as unemployment. Further research is required to better understand the potential roles of these factors in suboptimal adherence.

The WHO public health approach to HIV treatment and care: looking back and looking ahead

In 2006, WHO set forth its vision for a public health approach to delivering antiretroviral therapy. This approach has been broadly adopted in resource-poor settings and has provided the foundation for scaling up treatment to over 19·5 million people. There is a global commitment to end the AIDS epidemic as a public health threat by 2030 and, to support this goal, there are opportunities to adapt the public health approach to meet the ensuing challenges. These challenges include the need to improve identification of people with HIV infection through expanded approaches to testing; further simplify and improve treatment and laboratory monitoring; adapt the public health approach to concentrated epidemics; and link HIV testing, treatment, and care to HIV prevention. Implementation of these key public health principles will bring countries closer to the goals of controlling the HIV epidemic and providing universal health coverage.

The evolving role of CD4 cell counts in HIV care

PURPOSE OF REVIEW

The role of the CD4 cell count in the management of people living with HIV is once again changing, most notably with a shift away from using CD4 assays to decide when to start antiretroviral therapy (ART). This article reflects on the past, current and future role of CD4 cell count testing in HIV programmes, and the implications for clinicians, programme managers and diagnostics manufacturers.

RECENT FINDINGS

Following the results of recent randomized trials demonstrating the clinical and public health benefits of starting ART as soon as possible after HIV diagnosis is confirmed, CD4 cell count is no longer recommended as a way to decide when to initiate ART. For patients stable on ART, CD4 cell counts are no longer needed to monitor the response to treatment where HIV viral load testing is available. Nevertheless CD4 remains the best measurement of a patient's immune and clinical status, the risk of opportunistic infections, and supports diagnostic decision-making, particularly for patients with advanced HIV disease.

SUMMARY

As countries revise guidelines to provide ART to all people living with HIV and continue to scale up access to viral load, strategic choices will need to be made regarding future investments in CD4 cell count and the appropriate use for clinical disease management.

Results from implementing updated 2012 World Health Organization Guidance on early-warning indicators of HIV drug resistance in Zimbabwe

Objective

This study evaluated the performance of sentinel sites in preventing the emergence of HIVDR using Early Warning Indicators (HIVDR EWI) survey.

Methods

Adult and paediatric patient data on: On time pill pick up, Retention in care, Pharmacy stock-outs, and Dispensing practices was collected. Information from pharmacy registers was verified using facility-held cards. This was a cross-sectional analysis of retrospectively collected data from 72 sites providing both adult and paediatric ART as well as two providing adult ART only. All data were entered into and analysed using a WHO EWI data abstraction electronic tool.

Results

Twenty-one percent of sites providing adult and 4.2% of sites providing paediatric ART managed to meet the target for on time pill pick up. Retention in care indicator was met by 48.7% (95% CI: 36.9-60.6) of sites. ARV stock-outs occurred in 81.1% (95% CI: 70-89.3) adult sites and 63.9% (95% CI: 50-78.6) paediatric sites. ARVs were appropriately dispensed by 86.5% (95% CI: 75.6-93.3) of adult sites and 84.7% (95% CI: 74.3-92.1) of paediatric sites.

Conclusions

Most sites had low performance in many indicators in this survey and failed to meet the recommended targets. Some policies such as the current buffer stock and storage outside Harare should be revised in order to improve site access to ARVs. The country should prioritize the provision of viral load testing services in all provinces. The electronic patient management system should be rolled out to all ART sites to improve patient tracking and monitoring by sites.

Can HIV reverse transcriptase activity assay be a low-cost alternative for viral load monitoring in resource-limited settings?

OBJECTIVE

To evaluate the performance and cost of an HIV reverse transcriptase-enzyme activity (HIV-RT) assay in comparison to an HIV-1 RNA assay for routine viral load monitoring in resource limited settings.

DESIGN

A cohort-based longitudinal study.

SETTING

Two antiretroviral therapy (ART) centres in Karnataka state, South India, providing treatment under the Indian AIDS control programme.

PARTICIPANTS

A cohort of 327 HIV-1-infected Indian adult patients initiating first-line ART.

OUTCOME MEASURES

Performance and cost of an HIV-RT assay (ExaVir Load V3) in comparison to a gold standard HIV-1 RNA assay (Abbott m2000rt) in a cohort of 327 Indian patients before (WK00) and 4 weeks (WK04) after initiation of first-line therapy.

RESULTS

Plasma viral load was determined by an HIV-1 RNA assay and an HIV-RT assay in 629 samples (302 paired samples and 25 single time point samples at WK00) obtained from 327 patients. Overall, a strong correlation of r=0.96 was observed, with good correlation at WK00 (r=0.84) and at WK04 (r=0.77). Bland-Altman analysis of all samples showed a good level of agreement with a mean difference (bias) of 0.22 log10copies/mL. The performance of ExaVir Load V3 was not negatively affected by a nevirapine/efavirenz based antiretroviral regimen. The per test cost of measuring plasma viral load by the Abbott m2000rt and ExaVir Load V3 assays in a basic lab setting was $36.4 and $16.8, respectively.

CONCLUSIONS

The strong correlation between the HIV-RT and HIV-1 RNA assays suggests that the HIV-RT assay can be an affordable alternative option for monitoring patients on antiretroviral therapy in resource-limited settings.

TRIAL REGISTRATION NUMBER

ISRCTN79261738.

Antiretroviral therapy: Shifting sands

HIV/AIDS has been an extremely difficult pandemic to control. However, with the advent of antiretroviral therapy (ART), HIV has now been transformed into a chronic illness in patients who have continued treatment access and excellent long-term adherence. Existing indications for ART initiation in asymptomatic patients were based on CD4 levels; however, recent evidence has broken the shackles of CD4 levels. Early initiation of ART in HIV patients irrespective of CD4 counts can have profound positive impact on morbidity and mortality. Early initiation of ART has been found not only beneficial for patients but also to community as it reduces the risk of transmission. There have been few financial concerns about providing ART to all HIV-positive people but various studies have proven that early initiation of ART not only proves to be cost-effective but also contributes to economic and social growth of community. A novel multidisciplinary approach with early initiation and availability of ART at its heart can turn the tide in our favor in future. Effective preexposure prophylaxis and postexposure prophylaxis can also lower transmission risk of HIV in community. New understanding of HIV pathogenesis is opening new vistas to cure and prevention. Various promising candidate vaccines and drugs are undergoing aggressive clinical trials, raising optimism for an ever-elusive cure for HIV. This review describes various facets of tectonic shift in management of HIV.

Rationale and clinical utility of the darunavir-cobicistat combination in the treatment of HIV/AIDS

This article is to provide an update overview of cobicistat (COBI)-boosted darunavir in response to its recent approval by the US Food and Drug Administration, and inclusion as an alternative first-line regime in the 2015 treatment guidelines in the US. COBI is a relatively new non-antiretroviral cytochrome P450 3A inhibitor or pharmacoenhancer. The rationale behind COBI development was to provide an alternative to ritonavir (RTV) as a protease inhibitor pharmacoenhancer, due to associated adverse events with short- and long-term RTV use, such as gastrointestinal intolerability, drug–drug interactions, insulin resistance, lipodystrophy, and hyperlipidemia. Although in vitro studies suggest that COBI may result in a lower incidence of undesired drug–drug interactions and lipid-associated disorders than RTV, not all Phase III studies have well addressed these issues, and the data are limited. However, Phase III studies have demonstrated tolerability, noninferiority, and bioequivalence of COBI compared to RTV. Two main advantages of COBI over RTV-containing regimes have been noted as follows: 1) COBI has no anti-HIV activity; therefore, resistance to COBI as a booster in addition to protease inhibitor resistance is of little concern, allowing for COBI-containing regimes in future. 2) COBI’s solubility and dissolution rate allow for co-formulated/fixed-dose combination products. Nonetheless, prior to initiating COBI-containing treatment regimens, the following should be considered: 1) COBI may increase serum creatinine levels and reduce estimated glomerular filtration rate (GFR) without affecting actual GFR; 2) potential drug–drug interaction data are insufficient, warranting caution when initiating COBI in conjunction with concomitant medication or in individuals with multiple comorbidities; 3) food plays a pivotal role in boosting darunavir exposure, warranting caution and patient education on the importance of taking COBI-containing regimens with appropriate amounts of food; and 4) data on the success of COBI-containing regimens in treatment-experienced patients are limited.

Determination of HIV Status in African Adults With Discordant HIV Rapid Tests

BACKGROUND

In resource-limited settings, HIV infection is often diagnosed using 2 rapid tests. If the results are discordant, a third tie-breaker test is often used to determine HIV status. This study characterized samples with discordant rapid tests and compared different testing strategies for determining HIV status in these cases.

METHODS

Samples were previously collected from 173 African adults in a population-based survey who had discordant rapid test results. Samples were classified as HIV positive or HIV negative using a rigorous testing algorithm that included two fourth-generation tests, a discriminatory test, and 2 HIV RNA tests. Tie-breaker tests were evaluated, including rapid tests (1 performed in-country), a third-generation enzyme immunoassay, and two fourth-generation tests. Selected samples were further characterized using additional assays.

RESULTS

Twenty-nine samples (16.8%) were classified as HIV positive and 24 of those samples (82.8%) had undetectable HIV RNA. Antiretroviral drugs were detected in 1 sample. Sensitivity was 8.3%-43% for the rapid tests; 24.1% for the third-generation enzyme immunoassay; 95.8% and 96.6% for the fourth-generation tests. Specificity was lower for the fourth-generation tests than the other tests. Accuracy ranged from 79.5% to 91.3%.

CONCLUSIONS

In this population-based survey, most HIV-infected adults with discordant rapid tests were virally suppressed without antiretroviral drugs. Use of individual assays as tie-breaker tests was not a reliable method for determining HIV status in these individuals. More extensive testing algorithms that use a fourth-generation screening test with a discriminatory test and HIV RNA test are preferable for determining HIV status in these cases.

Quantitative Assessment of Intra-Patient Variation in CD4+ T Cell Counts in Stable, Virologically-Suppressed, HIV-Infected Subjects

Objectives

Counts of absolute CD4+ T lymphocytes (CD4+ T cells) are known to be highly variable in untreated HIV-infected individuals, but there are no data in virologically-suppressed individuals. We investigated CD4+ T cell variability in stable, virologically-suppressed, HIV-1 infected adults on combination antiretroviral therapy (cART).

Methods

From a large hospital database we selected patients with stable virological suppression on cART for >3 years with >10 CD4+ T cell measurements performed over a further >2 years; and a control group of 95 patients not on cART.

Results

We identified 161 HIV-infected patients on cART without active HCV or HBV infection, with stable virological suppression for a median of 6.4 years. Over the study period 88 patients had reached a plateau in their absolute CD4+ T cell counts, while 65 patients had increasing and 8 patients had decreasing absolute CD4+ T cell counts. In patients with plateaued CD4+ T cell counts, variability in absolute CD4+ T cell counts was greater than in percent CD4+ T cells (median coefficient of variation (CV) 16.6% [IQR 13.8-20.1%] and CV 9.6% [IQR 7.4-13.0%], respectively). Patients with increasing CD4+ T cell counts had greater variability in absolute CD4+ T cell counts than those with plateaued CD4 T cell counts (CV 19.5% [IQR 16.1-23.8%], p<0.001) while there was no difference in percent CD4+ T cell variability between the two groups. As previously reported, untreated patients had CVs significantly higher than patients on cART (CVs of 21.1% [IQR 17.2-32.0%], p<0.001 and 15.2% (IQR 10.7-20.0%), p<0.001, respectively). Age or sex did not affect the degree of CD4+ variation.

Conclusions

Adults with stable, virologically-suppressed HIV infection continue to have significant variations in individual absolute CD4+ T cell and percent CD4+ T cell counts; this variation can be of clinical relevance especially around CD4+ thresholds. However, the variation seen in individuals on cART is substantially less than in untreated subjects.

Discordant Impact of HLA on Viral Replicative Capacity and Disease Progression in Pediatric and Adult HIV Infection

HLA class I polymorphism has a major influence on adult HIV disease progression. An important mechanism mediating this effect is the impact on viral replicative capacity (VRC) of the escape mutations selected in response to HLA-restricted CD8+ T-cell responses. Factors that contribute to slow progression in pediatric HIV infection are less well understood. We here investigate the relationship between VRC and disease progression in pediatric infection, and the effect of HLA on VRC and on disease outcome in adult and pediatric infection. Studying a South African cohort of >350 ART-naïve, HIV-infected children and their mothers, we first observed that pediatric disease progression is significantly correlated with VRC. As expected, VRCs in mother-child pairs were strongly correlated (p = 0.004). The impact of the protective HLA alleles, HLA-B*57, HLA-B*58:01 and HLA-B*81:01, resulted in significantly lower VRCs in adults (p<0.0001), but not in children. Similarly, in adults, but not in children, VRCs were significantly higher in subjects expressing the disease-susceptible alleles HLA-B*18:01/45:01/58:02 (p = 0.007). Irrespective of the subject, VRCs were strongly correlated with the number of Gag CD8+ T-cell escape mutants driven by HLA-B*57/58:01/81:01 present in each virus (p = 0.0002). In contrast to the impact of VRC common to progression in adults and children, the HLA effects on disease outcome, that are substantial in adults, are small and statistically insignificant in infected children. These data further highlight the important role that VRC plays both in adult and pediatric progression, and demonstrate that HLA-independent factors, yet to be fully defined, are predominantly responsible for pediatric non-progression.

Ten priorities for expanding access to HCV treatment for people who inject drugs in low- and middle-income countries

Of the estimated 130-150 million people who are chronically infected with hepatitis C virus, around 90% reside in low- and middle-income countries. People who inject drugs are disproportionately affected by HCV, with a global estimated prevalence (based on serological reports of HCV antibodies) of 67%; world-wide over 10 million people who inject drugs are infected with HCV. Treatment for HCV has improved dramatically in recent years with the arrival of new direct acting antivirals (DAAs) and this is stimulating considerable efforts to scale up access to treatment. However, treatment coverage among the general population is less than 10% in most countries, and coverage for people who inject drugs is generally much lower. It is estimated that globally around 2 million people who inject drugs need treatment for HCV. The DAAs offer significant potential to rapidly expand access to treatment for HCV. While the ideal combination therapy remains to be established, key characteristics include high efficacy, tolerability, pan-genotypic activity, short treatment duration, oral therapy, affordability, limited drug-drug interactions, and availability as fixed-dose combinations and once daily treatments. This paper outlines 10 key priorities for improving access to HCV treatment for people who inject drugs: (1) affordable access to direct acting antivirals; (2) increased awareness and testing; (3) standardization of treatment; (4) simplification of service delivery; (5) integration of services; (6) peer support; (7) treatment within a framework of comprehensive prevention; (8) tracking progress; (9) dedicated funding; and (10) enabling policies.

CD4 enumeration technologies: a systematic review of test performance for determining eligibility for antiretroviral therapy

Background

Measurement of CD4⁺ T-lymphocytes (CD4) is a crucial parameter in the management of HIV patients, particularly in determining eligibility to initiate antiretroviral treatment (ART). A number of technologies exist for CD4 enumeration, with considerable variation in cost, complexity, and operational requirements. We conducted a systematic review of the performance of technologies for CD4 enumeration.

Methods and Findings

Studies were identified by searching electronic databases MEDLINE and EMBASE using a pre-defined search strategy. Data on test accuracy and precision included bias and limits of agreement with a reference standard, and misclassification probabilities around CD4 thresholds of 200 and 350 cells/μl over a clinically relevant range. The secondary outcome measure was test imprecision, expressed as % coefficient of variation. Thirty-two studies evaluating 15 CD4 technologies were included, of which less than half presented data on bias and misclassification compared to the same reference technology. At CD4 counts <350 cells/μl, bias ranged from -35.2 to +13.1 cells/μl while at counts >350 cells/μl, bias ranged from -70.7 to +47 cells/μl, compared to the BD FACSCount as a reference technology. Misclassification around the threshold of 350 cells/μl ranged from 1-29% for upward classification, resulting in under-treatment, and 7-68% for downward classification resulting in overtreatment. Less than half of these studies reported within laboratory precision or reproducibility of the CD4 values obtained.

Conclusions

A wide range of bias and percent misclassification around treatment thresholds were reported on the CD4 enumeration technologies included in this review, with few studies reporting assay precision. The lack of standardised methodology on test evaluation, including the use of different reference standards, is a barrier to assessing relative assay performance and could hinder the introduction of new point-of-care assays in countries where they are most needed.

Treatment to Prevent HIV Transmission in Serodiscordant Couples in Henan, China, 2006 to 2012

BACKGROUND

Antiretroviral therapy (ART) administered in clinical trial settings virtually eliminates the sexual transmission of human immunodeficiency virus (HIV) in serodiscordant couples, but effectiveness of treatment as prevention in the community is debated. Conflicting results from previous analyses in a Chinese cohort underscore the importance of determining effectiveness of ART delivered in resource limited settings.

METHODS

All available years of data (2006-2012) from local disease control records of HIV patients and their seronegative spouses in Henan Province, China, were analyzed using marginal structural Cox models to estimate the effect of ART in the initially infected partner his or her partner's HIV seroconversion risk.

RESULTS

We observed 157 seroconversion events in 4916 serosdiscordant couples, for an incidence rate of 0.59 cases per 100 person-years (PY) (95% confidence interval [CI], .51-.70). Of these, 84 occurred after the index partner had initiated ART (0.43/100PY; 95% CI, .35-.53) and 73, whereas index partners were untreated (5.87/100 PY; 95% CI, 4.65-7.42). In a marginal structural Cox model weighted for confounding and censoring, the hazard ratio (HR) for HIV transmission was 0.52 (95% CI, .34-.82). ART efficacy varied significantly by time period; least effective in the early phase from 2006 to 2008 (HR, 0.68; 95% CI, .34-1.36) but far more protective from 2009 onward (HR, 0.33; 95% CI, .20-.55).

CONCLUSIONS

ART can provide HIV-infected persons in resource-limited setting substantial protection against sexual transmission. Effectiveness in the Henan cohort appears to have increased over time, suggesting that quality of care and service infrastructure may be integral to successful use of treatment for prevention.

Synergistic vulnerabilities: antiretroviral treatment among women in Uganda

Despite being an early success story in the reduction of HIV infection rates, Uganda faces myriad challenges in the recent era of accelerated antiretroviral treatment (ARV) scale-up. For those able to access treatment, ongoing vulnerabilities of poverty and violence compound treatment-related costs and concerns. This paper explores experiences of one particularly vulnerable population - women on ARVs who have also experienced intimate partner violence (IPV). Data were collected over 12 months in Uganda. They include ethnographic interviews (n = 40) drawn from a larger sample of women on ARV and semi-structured interviews with policy-makers and service providers (n = 42), examining the intersection of experiences and responses to treatment from multiple perspectives. Women's narratives show that due to treatment, immediate health concerns take on secondary importance, while other forms of vulnerability, including IPV and poverty, can continue to shape treatment experiences and the decision to stay in violent relationships. Providers likewise face difficulties in overburdened clinics, though they recognise women's concerns and the importance of considering other forms of vulnerability in treatment. This analysis makes the case for integrating treatment with other types of social services and demonstrates the importance of understanding the ways in which synergistic and compounding vulnerabilities confound treatment scale-up efforts.

The future role of CD4 cell count for monitoring antiretroviral therapy

For more than two decades, CD4 cell count measurements have been central to understanding HIV disease progression, making important clinical decisions, and monitoring the response to antiretroviral therapy (ART). In well resourced settings, the monitoring of patients on ART has been supported by routine virological monitoring. Viral load monitoring was recommended by WHO in 2013 guidelines as the preferred way to monitor people on ART, and efforts are underway to scale up access in resource-limited settings. Recent studies suggest that in situations where viral load is available and patients are virologically suppressed, long-term CD4 monitoring adds little value and stopping CD4 monitoring will have major cost savings. CD4 cell counts will continue to play an important part in initial decisions around ART initiation and clinical management, particularly for patients presenting late to care, and for treatment monitoring where viral load monitoring is restricted. However, in settings where both CD4 cell counts and viral load testing are routinely available, countries should consider reducing the frequency of CD4 cell counts or not doing routine CD4 monitoring for patients who are stable on ART.

Absolute lymphocyte count is not a suitable alternative to CD4 count for determining initiation of antiretroviral therapy in fiji

Introduction. An absolute lymphocyte count is commonly used as an alternative to a CD4 count to determine initiation of antiretroviral therapy for HIV-infected individuals in Fiji when a CD4 count is unavailable. Methods. We conducted a retrospective analysis of laboratory results of HIV-infected individuals registered at all HIV clinics in Fiji. Results. Paired absolute lymphocyte and CD4 counts were available for 101 HIV-infected individuals, and 96% had a CD4 count of ≤500 cells/mm(3). Correlation between the counts in individuals was poor (Spearman rank correlation r = 0.5). No absolute lymphocyte count could be determined in this population as a suitable surrogate for a CD4 count of either 350 cells/mm(3) or 500 cells/mm(3). The currently used absolute lymphocyte count of ≤2300 cells/μL had a positive predictive value of 87% but a negative predictive value of only 17% for a CD4 of ≤350 cells/mm(3) and if used as a surrogate for a CD4 of ≤500 cells/mm(3) it would result in all HIV-infected individuals receiving ART including those not yet eligible. Weight, CD4 count, and absolute lymphocyte count increased significantly at 3 months following ART initiation. Conclusions. Our findings do not support the use of absolute lymphocyte count to determine antiretroviral therapy initiation in Fiji.

Emerging technologies for point-of-care management of HIV infection

The global HIV/AIDS pandemic has resulted in 39 million deaths to date, and there are currently more than 35 million people living with HIV worldwide. Prevention, screening, and treatment strategies have led to major progress in addressing this disease globally. Diagnostics is critical for HIV prevention, screening and disease staging, and monitoring antiretroviral therapy (ART). Currently available diagnostic assays, which include polymerase chain reaction (PCR), enzyme-linked immunosorbent assay (ELISA), and western blot (WB), are complex, expensive, and time consuming. These diagnostic technologies are ill suited for use in low- and middle-income countries, where the challenge of the HIV/AIDS pandemic is most severe. Therefore, innovative, inexpensive, disposable, and rapid diagnostic platform technologies are urgently needed. In this review, we discuss challenges associated with HIV management in resource-constrained settings and review the state-of-the-art HIV diagnostic technologies for CD4(+) T lymphocyte count, viral load measurement, and drug resistance testing.

Simplification of antiviral hepatitis C virus therapy to support expanded access in resource-limited settings

Currently, access to treatment for HCV is limited, with treatment rates lowest in the more resource-limited countries, including those countries with the highest prevalence. The use of oral DAAs has the potential to provide treatment at scale by offering opportunities to simplify drug regimens, laboratory requirements, and service delivery models. Key desirable characteristics of future HCV treatment regimens include high efficacy, tolerability, pan-genotype activity, short treatment duration, oral therapy, affordability, and availability as fixed-dose combination. Using such a regimen, HCV treatment delivery could be greatly simplified. Treatment could be initiated following confirmation of the presence of viraemia, with an initial assessment of the stage of liver disease. A combination DAA therapy that is safe and effective across genotypes could remove the need for genotyping and intermediary viral load assessments for response-guided therapy and reduce the need for adverse event monitoring. Simpler, safer, shorter therapy will also facilitate simplified service delivery, including task shifting, decentralization, and integration of treatment and care. The opportunity to scale up HCV treatment using such delivery approaches will depend on efforts needed to guarantee that the new DAAs are affordable in low-income settings. This will require the engagement of all stakeholders, ranging from the companies developing these new treatments, WHO and other international organizations, including procurement and funding mechanisms, governments and civil society.

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.

Cost-effectiveness of antiretroviral therapy expansion strategies in Vietnam

This study determines an optimal strategy for scaling up ART in Vietnam by examining three initiation thresholds [350 cells/mm(3), 500 cells/mm(3), and treat all people living with HIV (PLHIV) regardless of CD4 cell counts] and treatment commencement rates among treatment-eligible PLHIV ranging from 5% to 100% within 12 months of diagnosis. Incremental cost-effectiveness ratios (ICERs) were calculated using a Markov model, based on data from a cohort of 3449 patients who initiated ART between January 1, 2005 and December 31, 2009 in 13 outpatient clinics across six provinces in Vietnam. Our analyses indicated that raising treatment eligibility criteria, in line with WHO guidelines (CD4 ≤500 cells/mm(3)) or removing CD4-based criteria would both be cost-effective in Vietnam. However, the cost-effective strategy from an economic viewpoint is first to increase coverage substantially among those with lowest CD4 levels, and only when coverage increases towards saturation should initiation criteria be lifted. Universal coverage under current guidelines would cost an additional $85 million and $96 million per year if the treatment threshold was 500 cells/mm(3). These scenarios would avert 15,000 and 22,000 HIV-related deaths in 2010-2019, with ICERs of $500-$660 per QALY gained. It is imperative to increase treatment coverage for newly diagnosed PLHIV in Vietnam according to the current guidelines prior to increasing the CD4 threshold for ART initiation.

The 2013 WHO guidelines for antiretroviral therapy: evidence-based recommendations to face new epidemic realities

PURPOSE OF REVIEW

The review summarizes the key new recommendations of the WHO 2013 guidelines for antiretroviral therapy and describes the potential impact of these recommendations on the HIV epidemic.

RECENT FINDINGS

The 2013 WHO guidelines recommend earlier initiation of antiretroviral therapy (ART) at CD4 500 cells/μl or less for all adults and children above 5 years. Further recommendations include initiation of ART irrespective of CD4 cell count or clinical stage for people co-infected with active tuberculosis disease or hepatitis B virus with severe liver disease, pregnant women, people in serodiscordant partnerships, and children under 5 years of age. The ART regimen comprising a once daily fixed-dose combination of tenofovir + lamivudine (or emtricitabine) + efavirenz is recommended as the preferred first-line therapy. Several approaches are also recommended to reach more people and increase health service capacity, including community and self-testing, and task shifting, decentralization, and integration of ART care.

SUMMARY

If fully implemented, the 2013 WHO ART guidelines could avert at least an additional 3 million deaths and prevent close to an additional 3.5 million new infections between 2012 and 2025 in low- and middle-income countries, compared with previous treatment guidelines.

Adoption of national recommendations related to use of antiretroviral therapy before and shortly following the launch of the 2013 WHO consolidated guidelines

OBJECTIVE

To determine the status of key national policies on the use of antiretroviral therapy (ART) at the time of the launch of the 2013 WHO consolidated guidelines as well as to track early progress towards adoption of these recommendations following dissemination.

DESIGN

Descriptive analysis of global data on baseline ART policies as of June 2013 and early intentions to adopt the 2013 WHO for use of antiretroviral drugs guidelines as of November 2013.

METHODS

Compilation of existing global reports on key HIV policies, review of national guidelines, data collection through annual drug procurement surveys and through guidelines dissemination meetings in each of the six WHO regions.

RESULTS

Data were available from 124 low- and middle-income countries, including 97% of the 57 high-priority countries that have been identified by WHO and the Joint United Nations Program on HIV/AIDS (UNAIDS). At baseline, only one country reported recommending antiretroviral therapy (ART) at a CD4 T-cell count 250 cells/μl or less for adults and adolescents in 2013, whereas nine countries already recommended using CD4 T-cell count 500 cells/μl or less. Recommendations for ART initiation regardless of CD4 T-cell count for HIV-infected patients with tuberculosis (86%), hepatitis B (75%), all HIV-infected women who were pregnant or breastfeeding (option B+: 40%) or HIV-infected persons in a serodiscordant relationship (26%) had been nationally adopted as of June 2013. Eight of 67 countries (12%) already recommended treating all children less than 5 years of age. The triple antiretroviral combination of tenofovir + lamivudine (or emtricitabine) + efavirenz was recommended as the preferred first-line option for adults and adolescents more frequently (51%) than for pregnant women (38%), or for both adults/adolescents and pregnant women (28%; P < 0.05). Fewer than half (37%) of all countries reported recommending lopinavir/ritonavir for all HIV-infected children less than 3 years of age; 54% of countries reported recommending routine viral load monitoring, whereas only 41% recommended nurse-initiated ART.

CONCLUSIONS

A number of key WHO policy recommendations on antiretroviral drug use were adopted rapidly by countries in advance of or shortly following the launch of the 2013 guidelines. Efforts are needed to support and track ongoing policy adoption and ensure that it is accompanied by the scale-up of evidence-based interventions.

Integrated care as a means to improve primary care delivery for adults and adolescents in the developing world: a critical analysis of Integrated Management of Adolescent and Adult Illness (IMAI)

BACKGROUND

More than three decades after the 1978 Declaration of Alma-Ata enshrined the goal of 'health for all', high-quality primary care services remain undelivered to the great majority of the world's poor. This failure to effectively reach the most vulnerable populations has been, in part, a failure to develop and implement appropriate and effective primary care delivery models. This paper examines a root cause of these failures, namely that the inability to achieve clear and practical consensus around the scope and aims of primary care may be contributing to ongoing operational inertia. The present work also examines integrated models of care as a strategy to move beyond conceptual dissonance in primary care and toward implementation. Finally, this paper examines the strengths and weaknesses of a particular model, the World Health Organization's Integrated Management of Adolescent and Adult Illness (IMAI), and its potential as a guidepost toward improving the quality of primary care delivery in poor settings.

DISCUSSION

Integration and integrated care may be an important approach in establishing a new paradigm of primary care delivery, though overall, current evidence is mixed. However, a number of successful specific examples illustrate the potential for clinical and service integration to positively impact patient care in primary care settings. One example deserving of further examination is the IMAI, developed by the World Health Organization as an operational model that integrates discrete vertical interventions into a comprehensive delivery system encompassing triage and screening, basic acute and chronic disease care, basic prevention and treatment services, and follow-up and referral guidelines. IMAI is an integrated model delivered at a single point-of-care using a standard approach to each patient based on the universal patient history and physical examination. The evidence base on IMAI is currently weak, but whether or not IMAI itself ultimately proves useful in advancing primary care delivery, it is these principles that should serve as the basis for developing a standard of integrated primary care delivery for adults and adolescents that can serve as the foundation for ongoing quality improvement.

SUMMARY

As integrated primary care is the standard of care in the developed world, so too must we move toward implementing integrated models of primary care delivery in poorer settings. Models such as IMAI are an important first step in this evolution. A robust and sustained commitment to innovation, research and quality improvement will be required if integrated primary care delivery is to become a reality in developing world.