CROI 2016 Abstract eBook

Abstract Listing

Poster Abstracts

1044 Using Treatment As Prevention Could Eliminate the HIV Epidemic in MSM in Copenhagen Justin Okano 1 ; Danielle Robbins 1 ; Laurence Palk 1 ; Jan Gerstoft 2 ; Niels Obel 2 ; Sally Blower 1 1 Univ of California Los Angeles, Los Angeles, CA, USA; 2 Copenhagen Univ Hosp, Rigshospitalet, Copenhagen, Denmark

Background: The WHO has proposed using “treatment as prevention” (TasP) to eliminate HIV, and UNAIDS has proposed treatment targets to be met by 2021. However, the effectiveness of TasP in the “real-world” remains unknown. We determine the impact that TasP has had on the HIV epidemic in the MSM community in Copenhagen over the past ~20 years. UNAIDS has identified Copenhagen as a priority city, and the MSM community as a priority risk group, for HIV elimination. The WHO HIV elimination threshold is one new infection per 1,000 individuals per year. Methods: We use a Bayesian CD4-staged back-calculation approach to analyze historical treatment and diagnosis data from the Danish HIV Cohort Study (DHCS): we begin in 1996 when effective therapies were introduced. We then use a predictive model that simulates transmission dynamics from 2013 to 2025. The model is parameterized to reflect the epidemiological conditions in the MSM community in Copenhagen. The back-calculation model and DHCS treatment data provide initial conditions for the predictive model. Results: Our results show, between 1996 and 2013, the number of MSM in Copenhagen capable of transmitting HIV decreased by ~63%: from 2,218 (median, 95% Bayesian credible interval, BCI: 1,955-2,381) to only 819 (median, 95% BCI: 463-1,065). In addition, the annual number of new infections decreased by ~36%: from 117 (median, 95% BCI: 94-140) to 75 (median, 95% BCI: 20-117), see Figure. We estimate by 2013 treatment coverage had reached 73% (median, 95% BCI: 67-83%). We found coverage increased as incidence decreased. Using our transmission model we predict the WHO elimination threshold will be reached by 2021. We predict the annual incidence in 2021 will be 0.9 (median, BCI: 0.6-1.1) new HIV infections per 1,000 MSM. This will result in 51 (median, BCI: 39-64) new infections. Conclusions: Our study provides a proof-of-concept that TasP could be effective in eliminating HIV in resource-rich settings. Importantly, our results show that the HIV epidemic in the MSM community in Copenhagen is very close to the WHO elimination threshold. Notably, the conditions in Copenhagen have been optimal for TasP to have had a significant impact: high treatment coverage, high viral suppression rates, and high retention. Even under these optimal conditions, it has taken several decades for TasP to have a population- level effect. This implies that it will be essential to use other interventions, such as pre-exposure prophylaxis, in combination with TasP. Fig. 3A:

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1045 Estimated HIV Transmissions to Female Partners of HIV-Infected Men CyprianWejnert 1 ; Eli Rosenberg 2 ; Heather Bradley 1 ; Gabriela Paz-Bailey 1 ; H. Irene Hall 1 ; Jacek Skarbinski 1 ; Jonathan Mermin 1 ; Jeremy Grey 2 1 CDC, Atlanta, GA, USA; 2 Emory Univ, Atlanta, GA, USA Background: The majority of HIV-positive females acquired HIV through heterosexual contact. To better understand the dynamics of male-to-female HIV transmission, we used data on behaviors and viral suppression among HIV-positive males to model HIV transmissions to their female partners. Methods: Using weighted respondent-level data on risk behaviors and viral load of HIV-positive persons in the United States from CDC’s National HIV Behavioral Surveillance and Medical Monitoring Project, and population-size estimates from the National HIV Surveillance System, we developed a static, deterministic model to estimate the number of HIV

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CROI 2016