Emerging HIV-1 drug resistance after roll-out of antiretroviral therapy in sub-Saharan Africa:

Antiretroviral adherence interventions in Southern Africa: implications for using HIV treatments for prevention

There is concern that the expansion of ART (antiretroviral treatment) programmes to incorporate the use of treatment as prevention (TasP) may be associated with low levels of adherence and retention in care, resulting in the increased spread of drug-resistant HIV. We review research published over the past year that reports on interventions to improve adherence and retention in care in Southern Africa, and discuss these in terms of their potential to support the expansion of ART programmes for TasP. We found eight articles published since January 2012, seven of which were from South Africa. The papers describe innovative models for ART care and adherence support, some of which have the potential to facilitate the ongoing scale- up of treatment programmes for increased coverage and TasP. The extent to which interventions from South Africa can be effectively implemented in other, lower-resource Southern African countries is unclear.

Provision of antiretroviral therapy in South Africa: the nuts and bolts

Public sector antiretroviral provision had a slow start in South Africa despite a raging epidemic and a World AIDS conference that shed significant public light on the disparities of therapy access globally. This was largely due to political prevarication in the midst of AIDS denialism. There has been an unprecedented expansion in the HIV treatment programme since 2008. As a result, South Africa now has the largest number of patients on antiretroviral drugs in the world, and South African life expectancy has increased by more than a decade. However, this has led to a number of fiscal, logistic and operational challenges that the country must face as the treatment programme continues to expand. Challenges include increasing detection within communities, linkage and retention in care, while strengthening operational support functions such as consistent drug supply, health staffing and infrastructure, diagnostic services, programme monitoring and sustainable financing. As a middle-income country, albeit with marked income inequality, and the heaviest HIV burden in the world, South Africa is a test case of whether a large-scale public health programme can boast of success in the face of numerous other health-system challenges.

Short communication: east meets west: a description of HIV-1 drug resistance mutation patterns of patients failing first line therapy in PEPFAR clinics from Uganda and Nigeria

HIV-1 viral load (VL) monitoring is recommended but seldom performed in resource-constrained countries. An evaluation of patients receiving first-line antiretroviral therapy in a multicountry PEPFAR program (RV288) was performed to determine the rates and predictors of virologic suppression. Resistance data from treatment failures are available from Uganda and Nigeria. Each country enrolled 325 subjects into this cross-sectional study. Subjects on first-line therapy were randomly selected for HIV RNA testing (viral load). Regimens included efavirenz or nevirapine with zidovudine/lamivudine or tenofovir/lamivudine. VL was determined from plasma using the Roche COBAS TaqMan HIV-1 Test, High Pure System v1.0 (47 copies/ml). Genotypic resistance testing was performed on samples with VL>1,000 copies/ml. From Uganda, 85% of subjects were undetectable while 7% (23/325) had VL>1,000 copies/ml. The HIV-1 subtype distribution was as follows: A=47.6%, C=14.3%, and D=38.1%. No resistance mutations were found in 14% of subjects. All subjects with resistance had the M184V mutation. Of subjects failing a zidovudine regimen less than 1 year, 88% (7/8) had no thymidine analogue mutations (TAMs), compared to 50% (4/8) failing greater than 1 year. Four subjects (25%) had more than two mutations from the TAM-1 pathway (41L, 210W, 215Y). In Nigeria, 82% were undetectable while 14% (45/325) had VL>1,000 copies/ml. HIV-1 subtype distribution was as follows: 62.8%=CRF02_AG, 34%=pure G, and 2.8%=A. Of the 35 genotyped subjects, 14% (5/35) had no resistance mutations. Of the remainder, 10% (3/30) had no nucleoside analogue mutations while 33% (10/30) had only M184V along with nonnucleoside reverse transcriptase inhibitor (NNRTI) mutations. Forty percent (10/25) of subjects on zidovudine failed without TAMs. Another 25% (5/25) of subjects failing on zidovudine had more than two TAM-1 mutations. Individuals failing first-line antiretroviral therapy (ART) may retain sensitivity to one or more nucleoside analogues from the regimen. Knowledge of drug resistance patterns allow for selection of drugs that can be recycled in future regimens. Accumulation of resistance mutations may compromise future treatment options.

Cost-efficient HIV-1 drug resistance surveillance using multiplexed high-throughput amplicon sequencing: implications for use in low- and middle-income countries

OBJECTIVES

Increased trends of primary drug resistance mutations (DRMs) among treatment-naive HIV-1-infected patients in low- and middle-income countries (LMICs) and the non-availability of pre-antiretroviral therapy (ART) genotypic resistance testing (GRT) may severely affect future therapeutic outcomes. The main objective of this study was therefore to develop a simplified, cost- and labour-efficient but high-throughput GRT protocol to be applied in the large-scale surveillance of DRMs in LMICs.

PATIENTS AND METHODS

Ninety-six therapy-naive HIV-1-infected patients belonging to three cohorts were included: Indian patients followed at St John's Medical College Hospital, Bangalore, India (n = 49); East Africans (n = 21), who had migrated to Sweden; and Caucasians (n = 26) living in Sweden. GRT by population sequencing (GRT-PS) on individual plasma samples and GRT by next-generation sequencing (GRT-NGS) on equimolar multiplexed samples (n = 24) using Illumina MiSeq were performed.

RESULTS

The multiplexing procedure was shown to be technically feasible and gave high-quality reads independent of whether HIV-1 subtype C or B was analysed. GRT-NGS detected all the DRMs found by GRT-PS. Additional clinically important low-abundance (<20% of the viral population) major DRMs (e.g. K101E, K103N, Y181C and M184V) were detected by GRT-NGS but not by GRT-PS. The frequency of low-abundance DRMs was higher among East African compared with Indian and Caucasian individuals.

CONCLUSIONS

Our high-throughput next-generation sequencing with a multiplexed amplicon is a cost-efficient and promising approach for the large-scale surveillance of primary DRMs in LMICs where routine pre-ART GRT is not the standard of care. This strategy may be useful in optimizing future therapeutic regimens in those settings.

Field study of dried blood spot specimens for HIV-1 drug resistance genotyping

Dried blood spots (DBS) are an alternative specimen type for HIV drug resistance genotyping in resource-limited settings. Data relating to the impact of DBS storage and shipment conditions on genotyping efficiency under field conditions are limited. We compared the genotyping efficiencies and resistance profiles of DBS stored and shipped at different temperatures to those of plasma specimens collected in parallel from patients receiving antiretroviral therapy in Uganda. Plasma and four DBS cards from anti-coagulated venous blood and a fifth card from finger-prick blood were prepared from 103 HIV patients with a median viral load (VL) of 57,062 copies/ml (range, 1,081 to 2,964,191). DBS were stored at ambient temperature for 2 or 4 weeks or frozen at -80 °C and shipped from Uganda to the United States at ambient temperature or frozen on dry ice for genotyping using a broadly sensitive in-house method. Plasma (97.1%) and DBS (98.1%) stored and shipped frozen had similar genotyping efficiencies. DBS stored frozen (97.1%) or at ambient temperature for 2 weeks (93.2%) and shipped at ambient temperature also had similar genotyping efficiencies. Genotyping efficiency was reduced for DBS stored at ambient temperature for 4 weeks (89.3%, P = 0.03) or prepared from finger-prick blood and stored at ambient temperature for 2 weeks (77.7%, P < 0.001) compared to DBS prepared from venous blood and handled similarly. Resistance profiles were similar between plasma and DBS specimens. This report delineates the optimal DBS collection, storage, and shipping conditions and opens a new avenue for cost-saving ambient-temperature DBS specimen shipments for HIV drug resistance (HIVDR) surveillances in resource-limited settings.

Update on antiretroviral treatment during primary HIV infection

Primary HIV-1 infection covers a period of around 12 weeks in which the virus disseminates from the initial site of infection into different tissues and organs. In this phase, viremia is very high and transmission of HIV is an important issue. Most guidelines recommend antiretroviral treatment in patients who are symptomatic, although the indication for treatment remains inconclusive in asymptomatic patients. In this article the authors review the main virological and immunological events during this early phase of infection, and discuss the arguments for and against antiretroviral treatment. Recommendations of different guidelines, the issue of the HIV transmission and transmission of resistance to antiretroviral drugs, as well as recently available information opening perspectives for functional cure in patients treated in very early steps of HIV infection are also discussed.

The complexity of HIV persistence and pathogenesis in the lung under antiretroviral therapy: challenges beyond AIDS

Antiretroviral therapy (ART) represents a significant milestone in the battle against AIDS. However, we continue learning about HIV and confronting challenges 30 years after its discovery. HIV has cleverly tricked both the host immune system and ART. First, the many HIV subtypes and recombinant forms have different susceptibilities to antiretroviral drugs, which may represent an issue in countries where ART is just being introduced. Second, even under the suppressive pressures of ART, HIV still increases inflammatory mediators, deregulates apoptosis and proliferation, and induces oxidative stress in the host. Third, the preference of HIV for CXCR4 as a co-receptor may also have noxious outcomes, including potential malignancies. Furthermore, HIV still replicates cryptically in anatomical reservoirs, including the lung. HIV impairs bronchoalveolar T-lymphocyte and macrophage immune responses, rendering the lung susceptible to comorbidities. In addition, HIV-infected individuals are significantly more susceptible to long-term HIV-associated complications. This review focuses on chronic obstructive pulmonary disease (COPD), pulmonary arterial hypertension, and lung cancer. Almost two decades after the advent of highly active ART, we now know that HIV-infected individuals on ART live as long as the uninfected population. Fortunately, its availability is rapidly increasing in low- and middle-income countries. Nevertheless, ART is not risk-free: the developed world is facing issues with antiretroviral drug toxicity, resistance, and drug-drug interactions, while developing countries are confronting issues with immune reconstitution inflammatory syndrome. Several aspects of the complexity of HIV persistence and challenges with ART are discussed, as well as suggestions for new avenues of research.

Antiretroviral therapy for the prevention of HIV transmission: what will it take?

The evidence in support of use of antiretroviral therapy (ART) for prevention of human immunodeficiency virus (HIV) transmission is encouraging and has stimulated optimism for achieving a dramatic change in the trajectory of the HIV epidemic. Yet, there are substantial challenges that, if not addressed, could be the Achilles' heel for this concept. These challenges require strengthening every step of the HIV care continuum, including expansion of HIV testing to reach all those with HIV infection, effective linkage to and retention in care, timely initiation of ART, and high levels of treatment adherence with viral load suppression. Also important is the identification of individuals with acute HIV infection whose contribution to HIV transmission may be substantial. Implementation research is needed to identify strategies that address these challenges and to determine the efficacy of ART for prevention in key populations as well as to evaluate the effectiveness of combination strategies for HIV prevention at the population level.

Prediction of HIV drug resistance based on virologic, immunologic, clinical, and/or adherence criteria in the Stratall ANRS 12110/ESTHER trial in Cameroon

Our study in Cameroonian rural district hospitals showed that the immunologic and clinical failure criteria had poor performance to identify human immunodeficiency virus drug resistance in a timely manner. Switching to second-line antiretroviral therapy after 2 consecutive viral loads ≥5000 copies/mL, as recommended by the World Health Organization, appeared to be the most appropriate strategy.

Reasons for poor adherence to antiretroviral therapy postnatally in HIV-1 infected women treated for their own health: experiences from the Mitra Plus study in Tanzania

Background

In a study of prevention of mother-to-child transmission of HIV (PMTCT) by triple antiretroviral therapy (ART) in Dar es Salaam, Tanzania (the Mitra Plus study), retrospective viral load testing revealed a high and increasing frequency of detectable viral load during follow-up for two years postnatally in women given continuous ART for their own health suggesting poor adherence. This study explored women’s own perceived barriers to adherence to ART post-delivery so as to identify ways to facilitate better drug adherence among women in need of ART for their own health.

Methods

Semi-structured interviews were conducted with 23 of the 48 women who had detectable viral load at 24 months postnatally. Content analysis was used to analyze the data.

Results

Most women in the study did not acknowledge poor adherence until confronted with the viral load figures. Then, however, they revealed multiple reasons for failing to adhere. They said that their motivation to take ART decreased once they had protected their children from becoming infected and successfully weaned them. Feeling well for some, and a feeling of hopelessness for others, also decreased motivation to continue ART. The overwhelming demands of everyday life, poverty and lack of empowerment also posed significant barriers to long-term adherence. The need to keep their HIV status a secret and not let anyone see them taking the drugs was another steep barrier.

Conclusion

Reasons for postnatal failure to adhere by mothers put on ART for life during pregnancy included lack of motivation to continue ART after weaning the child, poverty and stigma. Projects that simultaneously address stigma, poverty and women’s lack of empowerment may be necessary for PMTCT and ART to reach their full potential. Our results indicate that the new WHO proposal to start all HIV-infected pregnant women on lifelong ART regardless of CD4 cell count needs to address the challenging realities of women in resource-poor contexts if it is to be successful.