Implementation and ethical dimensions of scaling up HIV ‘Treatment as Prevention’: Examining the experiences of people who inject drugs

In 2010, BC launched the Seek and Treat for Optimal Prevention of HIV/AIDS (STOP HIV) program, which implements antiretroviral Treatment as Prevention (TasP) through enhanced HIV testing and universal treatment for HIV-positive individuals. The success of TasP at the population level will be challenging. The needs for enhanced case-finding efforts, early treatment following HIV diagnoses, and consistent adherence to treatment regimes are among the top concerns, particularly with regard to a key target population for TasP: people who inject drugs (PWID).

This project will examine key implementation challenges and opportunities regarding PWID’s experiences with the testing, treatment and prevention imperatives of TasP policy and program delivery practices. The objectives are to:

  1. Collect and analyze interview accounts from PWID regarding their experiences with TasP
  2. Collect and analyze interview accounts of decision makers in order to characterize how various ethical and implementation considerations related to PWID are taken up or rejected
  3. Use the new information gathered to develop recommendations for tailoring TasP policies and program delivery practices to advance the effective and ethical scale-up of TasP among PWID

Supporting women’s sexual and reproductive health and rights through Treatment as Prevention: Investigating the impact of structural and interpersonal violence on HIV and reproductive health inequities among women living with HIV in British Columbia

BC's ambitious "90-90-90" target for 2020 aims to ensure that: 1) 90 percent of people living with HIV/AIDS are aware of their status; 2) 90 percent of those diagnosed receive sustained treatment; and 3) 90 percent of those being treated achieve viral suppression. Access and uptake from all affected groups in BC would be needed to achieve this. This work aims to identify and study barriers to HIV testing and treatment and reproductive health services (e.g. cervical screening, mammograms, fertility and pregnancy services) among marginalized women living with HIV/AIDS (WLWHA) in BC.

Specific areas of study will include:

  • Investigating the impact on disclosure of HIV status to health care providers and intimate partners of social factors such as:
    • criminalization of drug use and sex work
    • gender-based violence
  • Investigating the spatial distribution and accessibility of sexual and reproductive health services and their impact on reproductive health outcomes (e.g. contraceptive usage, cervical screening, unintended pregnancy)
  • Exploring challenges faced by WLWHA with families, including how caregiving demands and gender-based violence affect treatment access and compliance.

The intended outcome of the work is to recommend improved service delivery methods for HIV testing, treatment and reproductive health care with an ultimate goal of informing policies and programming.

Exploring the gendered dimensions of place, risk, and violence among street-involved youth who do sex work in Vancouver, Canada: A longitudinal ethnographic investigation

A growing body of evidence has shown that violence and other health-related risks are highly gendered, with a disproportionate burden experienced by young women and youth who do sex work in many settings. In Vancouver, escalating gentrification, the recent creation of supportive housing for “at-risk” youth, and legislative shifts in criminal policies around sex work and drug use have the potential to transform the landscape of violence, risk, and safety that youth who do sex work must navigate.

The proposed ethnographic study will explore how these processes of urban transformation are altering youth’s experiences and health outcomes over time. Key focuses will be youth’s social-spatial transitions in sex work (e.g. the transition from more isolated outdoor spaces to potentially safer indoor venues), and how these transitions exacerbate or mediate the production of violence and risk.

This research will be particularly concerned with how gender relations and inequities intersect with the production of violence and risk in particular sites. Moreover, it will focus on the continuum of violence experienced by youth in the city and how structural violence can produce interpersonal violence and risk in particular places.

This study will help produce a more nuanced understanding of young people’s lived experiences in the city over time, and the gendered production of risk and violence in urban space. This understanding is critical to developing and advocating for policy and “safer environment interventions” that are relevant to youth’s needs and capable of addressing the complex social processes that shape health outcomes for this youth population.

Responding to the health crisis among street-involved youth in Vancouver: Evidence to inform interventions and policy responses

Street-involved youth are extremely vulnerable to health-related harms resulting from high rates of illegal drug use and sexually-risky behaviour, poverty, and neglect, as well as precarious living conditions, either on the street or in risky relationships. There is an estimated 150,000 street youth in Canada, with approximately 40 percent reporting injection drug use. This puts street youth at a very high risk for sexually transmitted infections (STI) and hepatitis C (HCV) infection.

Dr. DeBeck’s research seeks to address gaps that exist in our understanding of how street youth are initiated in illegal drug use and the dynamic of how STI and HCV are transmitted.

Her work will examine individual (e.g. stimulant use), social (e.g. childhood trauma), structural (e.g. access and coverage of addiction treatment), and environmental (e.g. homelessness) factors and how they intersect to promote a “risk environment” that elevates sexual risk and drug-related harms.

The outcome of her analysis will be a body of evidence that can support the development and evaluation of behavioural and structural interventions to prevent sexual and drug-related harms among street-involved youth. Her work will also support clinical trials to address critical issues in the diagnosis and treatment of hepatitis C among street-involved youth.

Ultimately, the results of her work will help prevent high-risk drug use, infectious diseases and other health harms among street-involved youth. It will also provide critical guidance for the effective management and treatment of infectious diseases among street involved youth.


End of Award Update – April 2024

 

Results

Having dedicated research time through a Michael Smith/Providence Health Care Research Institute-St. Paul’s Hospital Scholar Award allowed Dr. DeBeck to build research networks and engage in inclusive collaborations through the At-Risk Youth Study (ARYS) cohort platform. As a Michael Smith Scholar she published more than 160 peer reviewed publications, 55 of which research trainees were the first author and she was the senior author. Dr. DeBeck has also been able to publish with nine different co-authors with lived or living experiences of substance use, the majority of whom identify as Indigenous. Her Scholar Award gave her time to network and collaborate with organizations like the Western Aboriginal Harm Reduction Society, the First Nations Health Authority, Vancouver Coastal Health and the BC Ministry of Mental Health and Addictions. She was also able to facilitate the creation of a program of ARYS Peer Research Associates (PRA) and more recently an Indigenous Peer Collaborators Circle to lead research involving Indigenous people who use drugs.

 

Impact

Collectively, Dr. DeBeck’s activities as a Michael Smith Scholar have contributed to a scientific evidence-based model that demonstrates that prevailing models of drug law enforcement are ineffective and carry serious unintended harms for structurally marginalized populations. Her work has documented that the criminalization of drug use hinders HIV prevention; incarceration is linked to a decreased likelihood of quitting drug injection and an increased likelihood of relapse into substance use; and incarceration has been discriminatory, disproportionately affecting young Indigenous people in Vancouver. Cumulatively, this body of work provides evidence that despite continuing to receive significant government funding, drug law enforcement has not been demonstrated to be effective and has serious unintended negative harms. This paves the way for evidence-based policy reforms that are not punitive in nature.

Other research contributions include characterizing the early stages of problematic substance use which underscores the role of social determinants of health (e.g., adverse childhood events, child welfare exposure, and intergenerational trauma) as drivers of substance. Documenting the role of social determinants of substance use draws attention to the necessity of policy reforms that attend to social and structural drivers of risk and counters popular narratives of individual moral failings and individual responsibility for substance use.

Contributions during her Scholar Award also include work on addiction treatment engagement that inform responses to the drug toxicity poisoning crisis. The policy implications of this body of work are that addiction treatment, despite demonstrated clinical effectiveness for some people who use drugs, has limited overall reach and impact. Based on these studies, expansion of addiction treatment cannot be expected to adequately respond to the toxic drug crisis. Additional interventions that span prevention and harm reduction, including addressing the toxic drug supply, are needed. Monitoring and evaluating innovative models that make regulated drugs or “safer supply” available is a critical next step for drug policy development and one that the ARYS cohort is ideally positioned to contribute to.

Another impact of Dr. DeBeck’s Scholar Award was the opportunity to leverage drug consumption data from the ARYS cohort and be part of the working group that drafted the City of Vancouver’s 2021 application to Health Canada for the decriminalization of drug possession. The introduction of drug decriminalizing has been symbolically monumental as it reflects the growing understanding that drug criminalization has been ineffective and harmful and different approaches to substance use are needed.

 

Potential Influence

Holding a Scholar Award allowed the ARYS cohort research platform to thrive under the leadership of Dr. DeBeck. It also gave her the opportunity to build critical research networks and collaborations that positioned her to transition to a CIHR Applied Public Health Chair and Dorothy Killam Fellowship in 2024. With this foundation in place, she is well positioned to continue to generate responsive, high-quality data to inform substance use interventions and drug policy. Current priorities are to engage in community-based collaboration with people who use drugs and government partners, to evaluate interventions and inform policy responses to prevent toxic drug poisonings, increase service engagement, and promote health and wellness among street-involved young people who use drugs in Vancouver and beyond.

 

Next Steps

With a CIHR APHC and Dorothy Killam Fellowship Dr. DeBeck can continue a research-intensive trajectory. Collaboration with ARYS PRAs and a newly formed Indigenous Peer Collaborator Circle are ongoing. Data sharing with government and community partners is also continuing with multiple research products under development.

 

Useful Links

Translation of next-generation sequencing to HIV treatment and prevention in British Columbia

Next-generation sequencing (NGS) is the automation of high-throughput DNA sequencing on a massive scale that is rapidly transforming biology and medicine. It can enable laboratories to detect small, but clinically significant, numbers of drug-resistant viruses in blood samples from infected individuals.

The lack of computational tools to process and interpret NGS data collected from rapidly-evolving populations such as HIV remains a major obstacle in the application of NGS to HIV treatment and prevention. Dr. Poon’s research will bridge this divide by developing computational methods for NGS analysis designed to address key issues in HIV prevention and treatment. He will share his software as a free resource to the basic and clinical research communities.

He will take advantage of resources available to him through the BC Centre for Excellence in HIV/AIDS (BC-CfE): an extensive archive of HIV plasma specimens; one of the world’s few NGS cores dedicated to HIV research; and his own expertise in molecular evolution and bioinformatic sequence analysis.

As part of his research, he is developing and validating a new method to reconstruct the time of HIV infection from NGS data. Using specimens from the BC-CfE, he will estimate times of HIV infection and reconstruct the historical trend of HIV incidence (the rate of new HIV infections) in BC. This will help assess the long-term impact of expanding access to HIV therapy in BC and identify other correlates of HIV incidence.

He will also use “phylogenetic” methods, which can infer the ancestral tree that relates observed genetic sequences, to reconstruct the history of HIV transmissions in BC. This will allow him to evaluate the impact of expanding access to HIV therapy in BC on the rate of transmitting drug-resistant HIV, and to characterize the variation in rates of HIV transmission over the course of the epidemic.

Finally, he will develop a new class of methods for analyzing NGS data to characterize the adaptation of HIV to the host-specific immune response, and to reconstruct the genetic sequence of the transmitted HIV strain. The results from these methods can provide key information for the development of HIV vaccine candidates – a core aim of HIV prevention research.

HIV risk environments among illicit drug users: A longitudinal ethno-spatial approach

Dr. Will Small’s research program will examine the influence of social, structural and physical environments upon illicit drug users’ HIV risk behaviour and HIV treatment-related outcomes. The study is nested within a larger program that includes three epidemiological cohort studies of adult drug users and street-involved youth. This approach integrates ethnographic observational fieldwork, in-depth interviews, and geo-spatial mapping techniques with quantitative laboratory and survey data to identify how the social, structural and physical features of drug-use scenes impact HIV outcomes.

Informed by ecological perspectives on health, and the HIV risk environment framework, this study will develop and pilot a novel ethno-spatial approach to identify the complex pathways and dynamics between contextual factors shaping the risk environments of drug use and HIV prevention and treatment for drug users. Building on 10 years of experience studying illicit drug use and HIV/AIDS in the local context, this program of ethno-spatial epidemiology seeks to address the following specific aims:

  1. Examine the influence of evolving social and physical features of “drug scenes” on HIV risk behaviours and HIV incidence among drug users.
  2. Assess the influence of evolving structural and physical factors on critical initiation and transitional events (e.g. initiation into drug use or sex work; transitions in drug use patterns) among drug users and inform epidemiological models of HIV risk.
  3. Examine the impact of evolving structural and physical factors on initiation and adherence to antiretroviral therapy and suppression of HIV-1 RNA among HIV-positive drug users.
  4. Create a platform for the ongoing ethno-spatial evaluation of future public health and public policy interventions targeting drug users.

Operations research applied to assess different strategies to reduce the public health and economic burdens of HIV/AIDS in British Columbia

Although traditional HIV prevention strategies — behaviour modification, condoms, needle exchange – have been very successful, their effect has reached a plateau since they are not always available, practical, or fully adhered to. In the past five years, research has shown that using antiretroviral therapy (ART) to treat those infected with HIV not only decreases mortality and morbidity but also decreases HIV transmission. Unfortunately, many individuals are still unaware that they are HIV-positive or that they should be on ART, since they have not been linked to our health-care system. These individuals will unnecessarily suffer from their disease and they will incur avoidable hospitalizations, physician visits, and costs.

Dr. Viviane Lima aims to identify different strategies to decrease the public health and economic burdens of HIV in British Columbia (BC). Since individuals living with HIV should follow the same continuum of care from infection until the time of first ART, diminishing the individual and economic burdens of HIV will require a combined effort of different players in our health-care system and the development of a comprehensive strategy to tackle each component in the continuum of care pathway. Lima’s research will employ innovative statistical and mathematical models to analyze these data and compare the potential effects of different complex strategies. This project will create great opportunities for trainees to be supported across a variety of disciplines, further enhancing BC’s competitive advantage in population-health and HIV research. The proposed methodology can also be applied to other diseases, conditions, and settings dealing with similar issues.

Health economic evaluation to inform strategies for HIV treatment and prevention

HIV treatment has advanced remarkably since 1996, with the advent of highly active antiretroviral therapy (HAART). HAART stops HIV replication and, as a result, the virus is reduced to undetectable levels. This allows immune reconstitution to take place, leading to long-term disease remission and prolonged survival.

The BC Centre for Excellence in HIV/AIDS (BC-CfE) has demonstrated that HAART renders HIV undetectable in sexual fluids and can dramatically reduce HIV transmission. As a result, the BC-CfE is engaged in a number of HIV “treatment as prevention” initiatives aimed at expanding HIV testing and treatment within BC and internationally to decrease HIV-related morbidity and mortality, as well as HIV transmission.

Dr. Bohdan Nosyk’s research is focused on cost-effectiveness analysis of treatment as prevention strategies to inform the most effective allocation of scarce health resources. The initial objective of this proposal is to construct a mathematical cohort simulation model to determine the cost-effectiveness of HAART scale-up in terms of the total costs accumulated, quality adjusted life years, and HIV incidence in BC from 1996 to 2010. A series of statistical and econometric analyses are required to estimate the relevant clinical and economic parameters needed to populate the simulation model. These analyses will be facilitated by the availability of linked administrative datasets and prospectively collected longitudinal data of HAART utilization, duration, and health outcomes at the population level in BC. The analyses will be stratified by HIV acquisition risk factor. This model will be used to predict the potential impact and cost-effectiveness of future policy changes in BC and internationally.