CROI 2019 Abstract eBook

Abstract eBook

Poster Abstracts

participants, long-term residents and non-users of illicit drugs, all previously associated with lower HIV risk. Conclusion: HIV incidence was generally higher in these observational cohorts before and concurrent to SiVET than in the SiVET participants. This difference was greatest among FF. Researchers designing HIV efficacy trials using observational cohort data need to consider the potential for lower than expected HIV incidence following screening and enrollment. 1089 THE PROJECTED AGE DISTRIBUTION OF WHITE, BLACK, AND HISPANIC MSM ON ART, 2009-2030 Parastu Kasaie 1 , Elizabeth Humes 2 , Stephen J. Gange 1 , Amy C. Justice 3 , Kelly Gebo 4 , Cynthia Boyd 2 , Emily P. Hyle 5 , Carolyn Williams 6 , Jinbing Zhang 1 , Raquel Cruz-Stratton 1 , Robert S. Hogg 7 , Mari Kitahata 8 , Richard D. Moore 4 , Keri N. Althoff 1 , for the North American AIDS Cohort Collaboration on Research and Design (NA-ACCORD) of IeDEA 1 Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA, 2 Johns Hopkins University, Baltimore, MD, USA, 3 VA Connecticut Healthcare System, West Haven, CT, USA, 4 Johns Hopkins University School of Medicine, Baltimore, MD, USA, 5 Massachusetts General Hospital, Boston, MA, USA, 6 National Institute of Allergy and Infectious Diseases, Bethesda, MD, USA, 7 Simon Fraser University, Burnaby, BC, Canada, 8 University of Washington, Seattle, WA, USA Background: There are unique age distributions for US Black, White, and Hispanic men who have sex with men (MSM) being treated for HIV infection. Underlying risk, prevention, testing and treatment factors may have created these differences in age distributions by race/ethnicity among MSM. This study aims to project the age distribution of these groups to the year 2030 to inform policy and planning. Methods: The NA-ACCORD was the source for mapping age distributions of those receiving ART in 2009, estimating the annual trend in age distribution of those initiating ART from 2009 to 2015, and modeling mortality rates as a function of time, CD4 count, and age at ART initiation among White, Black, and Hispanic MSM. Annual number of new HIV diagnoses and proportion of ART initiators among the race/ethnicity subgroups of MSMwere from the US Centers for Disease Control and Prevention. Assuming observed (2009-15) trends would be projected to 2030, these estimates informed an agent-based simulation modeling the dynamics of ART initiation, aging, and mortality among White, Black, and Hispanic MSM in the US. 100 independent runs allowed a precision level of <1% around the model’s estimates. Results: Observed age distributions for MSM subgroups in the NA-ACCORD from 2009-15 were a mixture of two distinct normally distributed age curves; this bimodal distribution was most distinct among Black MSM. Increased numbers of younger Black and Hispanic MSM on ART in the early Treat All era (2009-2015) impacted the projected age distribution to the year 2030, with younger age distributions among Black and Hispanic MSM and an older distribution among White MSM (Figure). As the number of White MSMs in the US is substantially greater than other racial groups, the overall age distribution of MSM with treated HIV shifted toward older ages through the year 2030. Conclusion: The differences in age distribution by race/ethnicity indicate substantive differences continue in risk, testing, and treatment. The increase in younger Black and Hispanic MSM on ART is an encouraging indicator of effective test and treat interventions. This modeling indicates that a substantial proportion of MSM on ART will continue to be in high transmission risk age groups, particularly Hispanics, even in 2030. Among White MSM, the observed increases in the proportion of older men alive on ART indicates access to, and success of, treatment. We can expect increasing numbers of older treated MSM into 2030 and a corresponding increase in multimorbidity.

Poster Abstracts

1090 YOUTH-FOCUSED HIV TREATMENT-AS-PREVENTION YIELDS LARGE BENEFITS: A SIMULATION MODEL John E. Mittler , James Murphy, Sarah E. Stansfield, Kathryn Peebles, Geoffrey S. Gottlieb, Neil Abernethy, Steven M. Goodreau, Joshua T. Herbeck University of Washington, Seattle, WA, USA Background: Despite increasing availability of Antiretroviral therapy (ART), heterosexual HIV-1 epidemics like those in sub-Saharan Africa continue to have high incidence in young people. ART for youth has the potential to protect their partners who also tend to be younger and at high risk. We hypothesized that focusing HIV interventions on youth could enhance the efficiency of treatment as prevention (TasP) campaigns in resource limited settings. Methods: We used an agent-based network model that includes behavioral and clinical data frommultiple sources to examine the effect of targeting different risk groups for linkage to HIV-related treatment services in a heterosexual population. The model accounts for age-based risk factors including the tendency for younger women to partner with older men. We used the model to identify strategies that reduce incidence to negligible levels 20-25 years after initiation of a targeted TasP campaign. Results: Under random allocation or CD4-based targeting, our model predicts a TasP campaign would need to suppress viral replication in 70-80% of infected people to halt the epidemic. Under age-based strategies, by contrast, this percentage drops to 40% to 60% (for strategies targeting those <30 and <25 years old, respectively) (Figure 1). Age-based targeting also minimized both total and time-discounted AIDS deaths after 25 years. Age-based targeting did not need to be highly exclusive to yield benefits; e.g. in a model in which 50% of infected people were treated, the majority of those people receiving therapy during a campaign targeting those <30 fell outside the target group. Sensitivity analyses varying background incidence yielded qualitatively similar benefits. Age-based TasP is beneficial due to age-related risk factors (e.g. shorter

CROI 2019 429