CROI 2015 Program and Abstracts

Abstract Listing

Oral Abstracts

In concentrated epidemics, such as amongst MSM in Europe, phylogenetics has been used to characterize transmission patterns. After reviewing key results in the area, I will focus on recent phylogenetic studies conducted in the Netherlands, where the epidemic amongst MSM has been increasing in recent years. We determined the characteristics and dynamics of different transmission clusters, and found that the epidemic was diffuse, with a large number of clusters sharing similar dynamics. We find that the epidemic is continuously replenished by the formation of new clusters amongst younger individuals. Next, by zooming in on probable transmission pairs, we quantified transmission rates throughout the stages of infection, starting from acute infection and through the different stages of the care and treatment continuum. We found that HIV prevention requires a combination of improvements in take-up of testing, speedy treatment initiation, and rapid viral suppression. I will conclude by describing next-generation sequencing data from different settings. Here, the whole viral genome is reconstructed, and a measure of diversity within samples is also obtained. Dual infection can be identified with relative ease, and is observed in all studied populations. These techniques yield large increases in phylogenetic resolution, such that sub-epidemics can be more clearly delineated. I will describe how phylogenetics is becoming part of the standard toolkit of HIV prevention studies. All work described is joint work with the HIV Monitoring Foundation in Amsterdam, the BEEHIVE collaboration, the PANGEA-HIV consortium, the HPTN 071 study team, and my research group at Imperial College. 128 Optimizing ART: Treatment as Prevention in the US: Will It Be Enough? Richard A. Elion Whitman-Walker Health, Washington, DC, US The success of treatment as prevention (TASP) for HIV has resulted in a significant reduction in rates of transmission. These declines are reflected in some municipalities as HIV incidence has diminished by upwards of 50% in some areas. These benefits have not been consistent across communities, as reflected through variable HIV suppression rates in the HIV treatment cascade in different communities. Nearly 90% viral suppression rates are seen in clinical trials, yet numerous models of HIV cascade success demonstrate viral suppression rates ranging from approximately 30% -70%. The impact of treatment as prevention is clear in cities where this approach has been widely adopted, but the declines in HIV incidence level off within 2 years and plateau. These benefits are substantial, but inadequate if our goal is to give birth to an HIV free generation. TASP can be improved, but must be complemented by aggressive prevention services. Pre Exposure Prevention is an important adjunct, as we just can’t treat our way out of the epidemic. Integration of preventive services into HIV service models is essential as we expand the model of HIV care to a community oriented primary care model. Changes in educational models that stress engagement and empowerment on a community level are essential to bring parity to emerging communities at risk for HIV and other STDs. Harm reduction strategies that treat biological consequences of behavior can offer deeper reductions in HIV through prep and sterile injections. The final mile in the delivery of optimal suppression is the hardest and involves social and health equalities. The differing models of the cascade illustrate the role of adequate insurance and social class. Both Washington DC as typified by a well functioning community health center that has nearly 100% coverage for health insurance and the Kaiser Permanente system have near universal coverage but suppression rates that vary greatly. Access can partially explain these differences, but class and poverty contribute to mental health and substance abuse, and may serve our toughest hurdle to cross. 129 Criminalizing HIV: Recent Experience in the United States and Africa to Update Laws and Policies to Promote the Public Health Jeffrey Crowley Georgetown University, Washington, DC, US Laws and policies have been used to protect people living with HIV and affected communities from stigma and discrimination. Indeed, the Americans with Disabilities Act (ADA) and the UN Convention on the Rights of Persons with Disabilities are just two legal instruments that help to create environments where people feel safe enough to come forward for HIV testing and to engage in care. Laws and policies also are used in ways that are highly stigmatizing and that hinder public health approaches to responding to HIV. In the United States, thirty-four states and territories have laws that criminalize the conduct of people living with HIV based on perceived exposure to HIV and without any evidence of intent to do harm. Far from representing a legacy of the past, people with HIV continue to be prosecuted and jailed for failure to disclose their HIV status prior to engaging in sex and for spitting and biting offenses, often in the context of arrest by law enforcement. Moreover, this is a challenge in countries across the globe. As of 2013, twenty-six African countries had overly broad and/ or vague HIV-specific criminal laws, most enacted over the past decade, with a further three countries considering new HIV-specific criminal laws. As governments, clinicians, researchers, and advocates seek to maximize population-level HIV viral suppression both to protect the health of people with HIV and also to reduce HIV transmission, these laws and policies could hinder our collective efforts. This talk will examine the current landscape of HIV criminal laws and policies in the US and selected African countries, will examine available data on the effectiveness of such laws at deterring behaviors such as failure to disclose HIV status prior to sexual encounters, and will look for common lessons from both Africa and the US to suggest a path forward for promoting effective evidence-based approaches to reducing HIV transmission. Session S-6 Symposium Room 6E 4:00 pm– 6:00 pm Tuberculosis: Magic Bullets and Moving Targets 130 Advances in Mycobacterial Diagnostics Mark P. Nicol University of Cape Town, Cape Town, South Africa The past 10 years have seen rapid advances in mycobacterial diagnostics. Specifically, nucleic acid amplification testing has been validated and widely implemented for both TB diagnosis and for identification of resistance to first and second line anti-TB drugs. The World Health Organization has recommended use of Xpert MTB/RIF (Xpert) as the initial diagnostic test for TB in high HIV or drug-resistant TB settings, including testing of children and for specific forms of extra-pulmonary TB. Xpert simultaneously detects M. tuberculosis and identifies rifampicin resistance, has excellent specificity and improved sensitivity over smear microscopy for diagnosis of TB, but lacks sufficient sensitivity for use as a rule-out test for HIV-associated TB. Studies assessing the impact of Xpert implementation have shown mixed results, particularly where empiric treatment is common; as such treatment may reduce the impact of Xpert on case detection. The role of Xpert in reducing time to treatment, outcome and transmission of drug-resistant TB is an important area for further research. Several other genotypic tests are now used for identification of resistance to first and second line anti-TB drugs. These detect the absence of wild-type (sensitive) sequence and/ or the presence of known resistance-conferring mutations. Line probe assays are commonly used, however targeted sequencing and whole genome sequencing are likely to be increasingly used as they provide improved specificity and broader mutation detection. Obstacles to the widespread implementation of sequencing include limited data on the genotype-phenotype relationship for many drugs, the lack of ‘plug and play’ pipelines for bioinformatics analysis and cost.

Oral Abstracts

162

CROI 2015